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ABSTRACT: We report an interesting case of Bancroftian filariasis diagnosed on fine needle aspiration cytology in a young female hailing from a non-endemic hilly area of India, who presented with a subcutaneous swelling on the left forearm. This is an unusual extra-lymphatic site to harbor filarial infestation and the cytology smears showed adult worms, eggs, and microfilariae of Wuchereria bancrofti. [ABSTRACT FROM AUTHOR]

Dirofilariasis, caused by the nematode Dirofilaria spp., poses significant challenges in diagnosis due to its diverse clinical manifestations and complex life cycle. This comprehensive literature review focuses on the evolution of diagnostic methodologies, spanning from traditional morphological analyses to modern emerging techniques in the context of dirofilariasis diagnosis. The review traces the historical progression of diagnostic modalities, encompassing traditional approaches such as microscopic examination, serological tests (including ELISA and IFA), radiographic imaging, ultrasonography, and necropsy, which laid the foundation for subsequent advancements. The integration of molecular diagnostics marks a significant turning point in dirofilariasis diagnosis with the adoption of polymerase chain reaction (PCR) assays and real-time PCR (qPCR) facilitating enhanced sensitivity and specificity. Furthermore, recent strides in nextgeneration sequencing (NGS) technologies, including whole-genome sequencing (WGS), targeted sequencing (TS), metagenomic sequencing (MS), and RNA sequencing (transcriptome sequencing), have revolutionized the landscape of dirofilariasis diagnostics. Emerging techniques such as loop-mediated isothermal amplification (LAMP), digital PCR (dPCR), and digital microfluidics are also explored for their potential to augment diagnostic accuracy. The review addresses challenges associated with standardizing molecular protocols, tackling false positives/negatives, and discusses the advantages and limitations of each technique. By providing a comprehensive overview of dirofilariasis diagnostic strategies, from traditional to cutting-edge methods, this review aims to enhance understanding of the disease's diagnostic landscape. The insights gained have implications for improved disease management and guide future research endeavors toward refining diagnostic protocols and advancing therapeutic interventions. [ABSTRACT FROM AUTHOR]

Filariasis is a very important public health problem endemic in tropical and subtropical countries. It is a debilitating disease with significant socioeconomic burden. In 2016, lymphatic filariasis was successfully eliminated from the Maldives, which was certified by WHO. We report a case of filariasis detected by a rapid antigen test while undergoing a screening program conducted by Health Protection Agency, Maldives in December 2023. The patient was asymptomatic and showed no peripheral blood eosinophilia. Conventional blood smears were negative. Nevertheless, buffy coat smear served as a promising test in detection of parasite, thus confirming the re-emergence of the disease in the country. Therefore, our study highlight the significance of buffy coat smears in detection of hemoparasites. We also focus on the importance of surveillance system in order to sustain the disease elimination goal that was already achieved.

Setaria equina is a common parasitic infection in horses that is transmitted by mosquitoes. The absence of previous reports regarding the presence of Setaria equina microfilariae in Nigerian horses highlights the need to confirm its existence in the region. Verifying the existence of this parasite would enhance our overall understanding of its global distribution, which could then inform the development of more effective control measures. This paper reports a case of Setaria equina microfilariae infection in an adult Argentine polo pony mare in Nigeria. The recently acquired adult Argentine polo pony mare was exhibiting depression and weight loss. Despite normal vital parameters, the horse had a poor body condition and no history of deworming. Laboratory analyses, including wet blood film examination, complete blood count, and serum biochemistry, revealed the presence of Setaria equina microfilariae and macrocytic hypochromic anaemia. Treatment involved a five-day course of intramuscular multivitamin injections and three weeks of subcutaneous ivermectin injections. Follow-up examinations demonstrated the absence of microfilaria and a return to an active and lively state. The case report details the clinical presentation, diagnostic process, and successful treatment of a recently acquired adult Argentine polo pony mare. A consistent deworming regimen is essential for horses, including those recently acquired, to prevent parasitic infections and enhance their overall well-being.

Abstract Dirofilaria immitis is a mosquito-borne parasitic nematode that causes fatal heartworm disease in canids. The microfilariae are essential for research, including drug screening and mosquito-parasite interactions. However, no reliable methods for maintaining microfilaria long-term are currently available. Therefore, we used severe combined immunodeficiency (SCID) mice to develop a reliable method for maintaining D. immitis microfilaria. SCID mice were injected intravenously with microfilariae isolated from a D. immitis-infected dog. Microfilariae were detected in blood collected from the tail vein 218 days post-inoculation (dpi) and via cardiac puncture 296 dpi. Microfilariae maintained in and extracted from SCID mice showed infectivity and matured into third-stage larvae (L3s) in the vector mosquito Aedes aegypti. L3s can develop into the fourth stage larvae in vitro. Microfilariae from SCID mice respond normally to ivermectin in vitro. The microfilariae in SCID mice displayed periodicity in the peripheral circulation. The SCID mouse model aided in the separation of microfilariae from cryopreserved specimens. The use of SCID mice enabled the isolation and sustained cultivation of microfilariae from clinical samples. These findings highlight the usefulness of the SCID mouse model for studying D. immitis microfilaremia in canine heartworm research.

Introduction: Filariasis, a parasitic infection caused by several types of nematode worms, is a matter of great concern for public health in India, The disease is caused by microfilaria, which are released into the peripheral blood circulation with periodicity during the night. However, identifying microfilaria in routine peripheral blood smears, Fine Needle Aspiration (FNAC) smears, and body fluids is challenging due to their scarce nature. Our study aimed to underscore the significance of having a heightened suspicion of filarial infection in patients with swelling, particularly those from endemic regions. Furthermore, the study emphasised the importance of using FNAC as an economical and effective diagnostic tool for detecting microfilaria. Materials and Methods: This retrospective study was conducted in the Pathology Department of ESIC Medical College and Hospital Gulbarga over a period of ten years (2013-2023). A 22-23 gauze needle made aspiration smears were stained by Papanicolaou and May-Grünwald Giemsa stain. Results: In this study, 24 cases showed the presence of microfilaria, a type of parasitic worm, despite the lack of clinical suspicion. Of these cases, eight involved breast lumps, eight involved thyroid swelling, and eight involved lymph nodes. In fifteen of these cases, fragments of adult worms were also reported, indicating a potentially more severe infection. These findings suggest the need for more diligent screening and testing to detect and treat parasitic infections before they can cause further harm. Conclusion: Filariasis is a rare disease that requires thorough screening of FNA smears, particularly in asymptomatic patients from endemic regions, to avoid missing incidental findings. Moreover, the study emphasises the cost-effectiveness and efficacy of FNAC in diagnosing microfilaria. [ABSTRACT FROM AUTHOR]

Elaeophorosis, infection by the filarial worm Elaeophora schneideri, is a parasitic disease of wild ungulates in North America; however, our understanding of the relevance of E. schneideri to moose (Alces alces) morbidity and mortality is incomplete. Between March 2020 and July 2022, necropsy and histopathology were performed on 61 Shiras moose (Alces alces shirasi) in Idaho, US. Among the 41 adults (greater than 1 yr old), 21 moose were from northern Idaho, and 20 were from southeastern Idaho. Elaeophorosis was diagnosed in 24% (10 of 41). All 10 infected moose were from southeastern Idaho; none of the 21 moose from northern Idaho were infected. No juvenile moose (nine from northern and 11 from southeastern Idaho) were infected. Microfilariae were detected histologically in 9 of 10 infected moose, most consistently in brain tissue associated with lesions indicative of ischemic injury to the neuroparenchyma attributed to occlusion of arterioles and capillaries by microfilariae or fibrin thrombi, including edema, necrosis, and glial nodules. Microfilariae found in other tissues of the head, including the eye, tongue, and pinnae of some animals, as well as in lung, heart, liver, and kidney, typically were associated with inflammation. Three of the 10 infected moose had cropped ears attributed to elaeophorosis, and four exhibited abnormal behavior, which may have been due to neuropathology associated with E. schneideri microfilariae in the brain. [ABSTRACT FROM AUTHOR]

Dirofilaria immitis is a mosquito-borne parasitic nematode that causes fatal heartworm disease in canids. The microfilariae are essential for research, including drug screening and mosquito-parasite interactions. However, no reliable methods for maintaining microfilaria long-term are currently available. Therefore, we used severe combined immunodeficiency (SCID) mice to develop a reliable method for maintaining D. immitis microfilaria. SCID mice were injected intravenously with microfilariae isolated from a D. immitis-infected dog. Microfilariae were detected in blood collected from the tail vein 218 days post-inoculation (dpi) and via cardiac puncture 296 dpi. Microfilariae maintained in and extracted from SCID mice showed infectivity and matured into third-stage larvae (L3s) in the vector mosquito Aedes aegypti. L3s can develop into the fourth stage larvae in vitro. Microfilariae from SCID mice respond normally to ivermectin in vitro. The microfilariae in SCID mice displayed periodicity in the peripheral circulation. The SCID mouse model aided in the separation of microfilariae from cryopreserved specimens. The use of SCID mice enabled the isolation and sustained cultivation of microfilariae from clinical samples. These findings highlight the usefulness of the SCID mouse model for studying D. immitis microfilaremia in canine heartworm research. [ABSTRACT FROM AUTHOR]

Background and Aim: Filarial nematode typically produces a larval stage (microfilariae) in the bloodstream of vertebrate hosts, where microfilariae reside in the blood or subcutaneous tissues. Filarial nematodes cause human diseases, such as river blindness and elephantiasis, which are widely studied. However, in avian species, they are overlooked because they are nonpathogenic. In Thailand, microfilaria can be found in wild birds and domestic chickens. Recently, an increase in the number of blood samples submitted to veterinary diagnostic laboratories may have increased the number of microfilariae. Therefore, knowledge about filarial species and reliable detection methods are important. Therefore, this study aimed to investigate the efficacy of buffy coat smear and polymerase chain reaction (PCR)-based methods for the detection of microfilaria in domestic chickens. In addition, parasites were identified using the sequence of the cytochrome c oxidase subunit 1 (COX1) gene. Materials and Methods: Giemsa-stained buffy coat smears from a previous study were reanalyzed. These available buffy coat smears were prepared from 55 domestic chickens raised as backyard free-ranging in Southern Thailand. Fifty-seven frozen genomic DNA extracted from chicken blood were used to detect the presence of the COX1 gene in Onchocercidae nematodes. The nested PCR protocol for amplification of the OnchoCOI_ R2-OnchoCOI_ R2 fragment of the COX1 gene was applied from a previous report. Sequences of COX1 were analyzed to identify Onchocercidae nematodes and if they were single or mixed infections. We constructed Bayesian phylogenetics to identify parasites and assessment of the relationship between filarial nematodes in avian species and other vertebrate hosts. Results: Buffy coat smears from 15 samples revealed microfilaria. Of these 15 samples, only eight were positive for COX1 nested-PCR amplification. The other two buffy coat-negative samples were also positive for nested-PCR. Sequencing of these 11 nested PCR-positive samples revealed that almost all of them were Onchocercidae nematodes. Bayesian phylogenetic analysis showed that chicken Onchocercidae spp. were grouped with other avian filarial nematodes. However, all chickens Onchocercidae spp. showed a double peak in the sequencing chromatogram, indicating mixed filarial infection (species or haplotypes). Therefore, no chicken Onchocercidae sequence was deposited on National Center for Biotechnology Information, GenBank. Conclusion: Giemsa-stained buffy coat smear was a reliable method for the detection of chicken microfilaria in routine veterinary diagnostic laboratories. Development of a new PCR-based method is necessary. This method may provide greater sensitivity and specificity of detection. In addition, the PCR method allowed us to access the genetic characteristics of nematodes, which helped us maximize our knowledge of nematodes. Further investigations, such as the pathogenicity of filarial nematodes in chickens and their potential vectors, are required.

Abstract Background Onchocerciasis causes chronic systemic inflammation. Several studies have used markers such as haemato-biochemical indices to predict the occurrence of systemic inflammation. This study assessed the variability and predictability of haemato-biochemical indices and blood composite ratios (BCRs) in microfilariae positive (MF+) and microfilariae negative (MF-) subgroups of onchocercomata participants. Methods One hundred and five (105) MF + and 34 MF- participants were retrospectively recruited into the study. Screening for the presence of O. volvulus microfilariae was done from skin snips taken from the left and right iliac crests of participants using established and approved protocols. Haematological and biochemical indices were measured using standard laboratory automated analyzers. Blood composite ratios (BCRs) were calculated as ratios of the absolute parameters involved. Results A significantly increased total WBC, absolute eosinophil, eosinophil percent and absolute basophil were observed in the MF + participants compared to MF- participants. Reduced gamma-glutamyl transferase (GGT) with increased estimated glomerular filtration rate (eGFR) was significantly associated with MF + participants compared to MF- participants. BCRs were significantly higher for eosinophil-to-neutrophil ratio (ENR), eosinophil-to-monocyte ratio (EMR), eosinophil-to-basophil ratio (EBR) and eosinophil-to-lymphocyte ratio (ELR) in MF + participants compared to MF- participants. After multivariate adjustment, onchocercomata participants with increased eosinophil counts (aOR = 13.86, 95% CI [2.07–92.90], p = 0.007), ENR x10 (aOR = 1.42, 95% CI [1.05–1.93], p = 0.025), EMR (aOR = 2.64, 95% CI [1.25–5.60], p = 0.011), EBR (aOR = 1.07, 95% CI [1.01–1.10], p = 0.020) and ELR x10 (aOR = 1.69, 95% CI [1.14–2.51], p = 0.009) were more likely to have microfilaridermia. Conclusions Elevated eosinophil counts with higher ENR, EMR, EBR and ELR levels are significantly associated with microfilaridermia in onchocercomata participants. Combining BCRs with eosinophil count significantly led to an improvement in the conventional model for predicting microfilaridermia.

Microfilarial parasites can obstruct the lymphatic tree giving rise to varying lymphatic and extra-lymphatic symptoms. Renal manifestations can range from asymptomatic proteinuria, chyluria, and nephrotic syndrome, to acute glomerulonephritis. The diagnosis of filariasis is usually made by the demonstration of the parasite in the peripheral blood smear, with or without eosinophilia. The renal involvement by this parasite has been sparsely reported in the literature. We hereby report five cases of filariasis detected on histopathological examination of renal biopsies, performed for other indications, along with a brief report of the additional histological findings. Three native and two graft biopsies were included. All our patients were male, with a mean age of 47 years (range 37 to 66 years). The serum creatinine ranged from 1.2 to 12.9 mg/dL. The mean 24-hour urinary protein was 3.6 gm/day. Peripheral blood eosinophilia was not recorded in any case, however, ESR was raised in all cases. Urine examination revealed varying proteinuria, with hematuria in two cases. Histological examination revealed microfilaria in all five biopsies, along with focal segmental glomerulosclerosis in two cases, combined cellular and humoral rejection, minimal change disease and acute tubular necrosis in one case each respectively. All patients were treated with diethylcarbamazine 6mg/kg/day or 12 days, in addition to the renal medications. Diagnosing the parasite is crucial as the patient is likely to benefit due to the timely treatment of the disease. Reporting this case series highlights an interesting finding in nephropathology. [ABSTRACT FROM AUTHOR]

Background and Aim: Filarial nematode typically produces a larval stage (microfilariae) in the bloodstream of vertebrate hosts, where microfilariae reside in the blood or subcutaneous tissues. Filarial nematodes cause human diseases, such as river blindness and elephantiasis, which are widely studied. However, in avian species, they are overlooked because they are nonpathogenic. In Thailand, microfilaria can be found in wild birds and domestic chickens. Recently, an increase in the number of blood samples submitted to veterinary diagnostic laboratories may have increased the number of microfilariae. Therefore, knowledge about filarial species and reliable detection methods are important. Therefore, this study aimed to investigate the efficacy of buffy coat smear and polymerase chain reaction (PCR)-based methods for the detection of microfilaria in domestic chickens. In addition, parasites were identified using the sequence of the cytochrome c oxidase subunit 1 (COX1) gene. Materials and Methods: Giemsa-stained buffy coat smears from a previous study were reanalyzed. These available buffy coat smears were prepared from 55 domestic chickens raised as backyard free-ranging in Southern Thailand. Fifty-seven frozen genomic DNA extracted from chicken blood were used to detect the presence of the COX1 gene in Onchocercidae nematodes. The nested PCR protocol for amplification of the OnchoCOI_R2-OnchoCOI_R2 fragment of the COX1 gene was applied from a previous report. Sequences of COX1 were analyzed to identify Onchocercidae nematodes and if they were single or mixed infections. We constructed Bayesian phylogenetics to identify parasites and assessment of the relationship between filarial nematodes in avian species and other vertebrate hosts. Results: Buffy coat smears from 15 samples revealed microfilaria. Of these 15 samples, only eight were positive for COX1 nested-PCR amplification. The other two buffy coat-negative samples were also positive for nested-PCR. Sequencing of these 11 nested PCR-positive samples revealed that almost all of them were Onchocercidae nematodes. Bayesian phylogenetic analysis showed that chicken Onchocercidae spp. were grouped with other avian filarial nematodes. However, all chickens Onchocercidae spp. showed a double peak in the sequencing chromatogram, indicating mixed filarial infection (species or haplotypes). Therefore, no chicken Onchocercidae sequence was deposited on National Center for Biotechnology Information, GenBank. Conclusion: Giemsa-stained buffy coat smear was a reliable method for the detection of chicken microfilaria in routine veterinary diagnostic laboratories. Development of a new PCR-based method is necessary. This method may provide greater sensitivity and specificity of detection. In addition, the PCR method allowed us to access the genetic characteristics of nematodes, which helped us maximize our knowledge of nematodes. Further investigations, such as the pathogenicity of filarial nematodes in chickens and their potential vectors, are required. [ABSTRACT FROM AUTHOR]

Dirofilaria immitis is a mosquito-borne nematode-causing canine heartworm disease, with adult worms localized in the pulmonary arteries and right heart. In rare cases, ectopic migration might occur, and adults and blood circulating microfilariae can be found in unusual organs or fluids (e.g., eyes, abdominal cavity, bone marrow, and urine). A 17-year-old mixed-breed female dog was presented in a private veterinary clinic in Italy for hematuria and dysuria. Physical examination showed cardiac mitral murmur with marked respiratory distress and cyanotic mucous membranes after handling. Abdominal ultrasounds revealed a non-specific chronic cystopathy, while the echocardiography showed enlargement of the right heart associated with tricuspid insufficiency and mitral regurgitation, with the presence of an adult filariae in the right ventricular chamber. Circulating microfilariae were observed in the blood smear and molecularly identified as D. immitis. Unusual microfilaruria was detected in the urine sediment. Data presented raise awareness about the occurrence of microfilariae in unusual locations, such as the bladder, suggesting the need of a thorough clinical and laboratory assessment where D. immitis is endemic. [ABSTRACT FROM AUTHOR]

Dirofilariasis, caused by the nematode Dirofilaria spp., poses significant challenges in diagnosis due to its diverse clinical manifestations and complex life cycle. This comprehensive literature review focuses on the evolution of diagnostic methodologies, spanning from traditional morphological analyses to modern emerging techniques in the context of dirofilariasis diagnosis. The review traces the historical progression of diagnostic modalities, encompassing traditional approaches such as microscopic examination, serological tests (including ELISA and IFA), radiographic imaging, ultrasonography, and necropsy, which laid the foundation for subsequent advancements. The integration of molecular diagnostics marks a significant turning point in dirofilariasis diagnosis with the adoption of polymerase chain reaction (PCR) assays and real-time PCR (qPCR) facilitating enhanced sensitivity and specificity. Furthermore, recent strides in next-generation sequencing (NGS) technologies, including whole–genome sequencing (WGS), targeted sequencing (TS), metagenomic sequencing (MS), and RNA sequencing (transcriptome sequencing), have revolutionized the landscape of dirofilariasis diagnostics. Emerging techniques such as loop-mediated isothermal amplification (LAMP), digital PCR (dPCR), and digital microfluidics are also explored for their potential to augment diagnostic accuracy. The review addresses challenges associated with standardizing molecular protocols, tackling false positives/negatives, and discusses the advantages and limitations of each technique. By providing a comprehensive overview of dirofilariasis diagnostic strategies, from traditional to cutting-edge methods, this review aims to enhance understanding of the disease’s diagnostic landscape. The insights gained have implications for improved disease management and guide future research endeavors toward refining diagnostic protocols and advancing therapeutic interventions.

An 11-year-old male dog presenting exophthalmia and perforation of the cornea of the left eye was seen at the veterinary hospital of the State University of Maranhão. Upon physical examination, irregularly shaped granulomas of crumbly appearance were observed on the dog’s tongue. The dog was sent for ocular enucleation surgery. The following tests were requested: complete blood count, serum biochemistry, hemoparasite investigation, chest X-Ray, echocardiogram, electrocardiogram, cytology and nodule histopathology. The blood count revealed neutrophilia, signs of anemia, increased total plasma protein and thrombocytopenia. Serum biochemistry and the imaging examinations showed normal results. The cytological examination on the tongue nodules showed microfilariae and the histopathological examination showed chronic glossitis. Polymerase chain reaction (PCR) and genetic sequencing were performed on a blood sample, which made it possible to identify the species Acanthocheilonema reconditum. This is the first record worldwide of the occurrence of microfilariae of A. reconditum on tongue nodules. This finding serves to alert dermatologists and dentists regarding the need for a differential diagnosis for types of oral cavity lesions of unknown etiological origin.

Reptiles are hosts for a wide variety of intra- or extracellular blood parasites that range from protozoan parasites to microflarid nematodes. Hemogregarines are found in many vertebrates, being the most prevalent apicomplexan parasites in reptiles. In this study, the prevalence and intensity of hemoparasites in Caucasian Agamid lizards, Paralaudakia caucasia was investigated. Blood smears were prepared, stained by gimsa, and were examined for the presence of haemoparasites. The light microscopic diagnosis detected parasites in two groups: Hepatozoon sp and Lankestrella sp were found as apicomplexan blood parasites and microflarial worms as nematods. The prevalence of infected lizards was 17.50 and 10 percent for Hepatozoon sp and Lankestrella sp. respectively. As well as 10 percent of lizards were infected by nematod worms. This report is the first survey of haemoparasites in these lizards. It revealed a high diversity of haemoparasites in lizards of the study region and highlighted the need to understand their impacts on hosts. [ABSTRACT FROM AUTHOR]

Lymphatic filariasis is a neglected tropical disease that affects the lymphatic system of humans. The major etiologic agent is a nematode called Wuchereria bancrofti, but Brugia malayi and Brugia timoriare sometimes encountered as causative agents. Mosquitoes are the vectors while humans the definitive hosts respectively. The burden of the disease is heavier in Nigeria than in other endemic countries in Africa. This occurs with increasing morbidity and mortality at different locations within the country, the World Health Organization recommended treatments for lymphatic filariasis include the use of Albendazole (400mg) twice per year in co-endemic areas with loa loa, Ivermectin (200mcg/kg) in combination with Albendazole (400mg) in areas that are coendemic with onchocerciasis, ivermectin (200mcg/kg) with diethylcarbamazine citrate (DEC) (6mg/kg) and albendazole (400mg) in areas without onchocerciasis. This paper covered a systematic review, meta-analysis, and scoping review on lymphatic filariasis in the respective geopolitical zones within the country. The literature used was obtained through online search engines including PubMed and Google Scholar with the heading "lymphatic filariasis in the name of the state", Nigeria. This review revealed an overall prevalence of 11.18% with regional spread of Northwest (1.59%), North Central and North East, (4.52%), South West (1.26%), and South-South with South East (3.81%) prevalence. The disease has been successfully eliminated in Argungu local government areas (LGAs) of Kebbi State, Plateau, and Nasarawa States respectively. Most clinical manifestations (31.12%) include hydrocele, lymphedema, elephantiasis, hernia, and dermatitis. Night blood samples are appropriate for microfilaria investigation. Sustained MDAs, the right testing methods, early treatment of infected cases, and vector control are useful for the elimination of lymphatic filariasis for morbidity management and disability prevention in the country. Regional control strategies, improved quality monitoring of surveys and intervention programs with proper records of morbidity and disability requiring intervention are important approaches for the timely elimination of the disease in Nigeria. [ABSTRACT FROM AUTHOR]

Background: Newer generation ophthalmologists practicing in the developed world are not very familiar with some tropical ocular diseases due to the absence of reports in the ophthalmic literature over the past thirty years. Because of world globalization or due to influx of immigrants from sub-Saharan Africa, exotic retinal diseases are being encountered more often in ophthalmology clinics. Methods: A multicenter case series of chorioretinitis or optic neuritis with obscure etiology that used serial multimodal imaging. Results: Four cases qualified with the diagnosis of presumed ocular onchocerciasis based on their residence near fast rivers in endemic areas, multimodal imaging, long term follow-up showing progressive disease and negative workup for other diseases. Characteristic findings include peripapillary choroiditis with optic neuritis or atrophy, subretinal tracts of the microfilaria, progressive RPE atrophy around heavily pigmented multifocal chorioretinal lesions of varying shapes, subretinal white or crystalline dots, and response to ivermectin. Typical skin findings are often absent in such patients with chorioretinitis rendering the diagnosis more challenging. Conclusions: Familiarity with the myriad ocular findings of onchocerciasis, and a high-degree of suspicion in subjects residing in endemic areas can help in the correct diagnosis and implementation of appropriate therapy. Onchocercal chorioretinitis is a slow, insidious, progressive, and prolonged polymorphous disease. [ABSTRACT FROM AUTHOR]

This article presents a case study of a 20-year-old Corolla wild horse stallion that was admitted to a veterinary teaching hospital with colic signs. The horse had previously been domesticated from a wild population and showed abnormal biochemistry findings, including mild hyperbilirubinemia and elevated liver enzymes. Blood smear evaluation revealed the presence of microfilariae, which were identified as Setaria equina through molecular analysis. The article discusses the potential causes of microfilaremia in horses and highlights the need for further research on the prevalence of S. equina in domestic and wild horse populations. [Extracted from the article]

Abstract Background In onchocerciasis-endemic areas with high ongoing Onchocerca volvulus transmission, a high prevalence of epilepsy has been reported. This study aimed to determine the prevalence and clinical characteristics of epilepsy in the Bono Region of Ghana following 27 years of implementation of ivermectin mass drug administration (MDA). Methods Between October 2020 and August 2021, cross-sectional surveys were conducted in nine communities in the Tain District and Wenchi Municipality of the Bono Region of Ghana. In the first stage, a random door-to-door approach was used to screen the population for epilepsy using a pre-tested questionnaire. Persons suspected of having epilepsy were invited for a second-stage neurological examination for case verification. Community O. volvulus microfilarial infection status and Ov16 seropositivity were also determined. Ninety-five confidence intervals (95% CI) for prevalence values were calculated using the Wilson Score Interval. Results Of the 971 participants, 500 (51.5%) were females, and the median age (interquartile range) was 26 (15‒43) years. Fourteen participants (1.4%, 95% CI: 1.0‒2.0) were diagnosed as having epilepsy with generalized seizures being the most frequent seizure type (85.7%, 12/14). The overall microfilarial prevalence of O. volvulus was 10.3% (November 2020) and 9.9% (August 2021); the Ov16 seroprevalence was 22.2% (June 2021). Only 63.2% took ivermectin in the last round of MDA distribution in March 2021. Conclusions The 1.4% prevalence of epilepsy in the Bono region is similar to the median epilepsy prevalence in sub-Saharan Africa. However, the persistent microfilarial prevalence and low ivermectin study coverage call for the Ghana Onchocerciasis Elimination Programme to step up its efforts to ensure that the gains achieved are consolidated and improved to achieve the elimination of onchocerciasis by 2030. Graphical Abstract

Key Clinical Message: Skin ulcerations are a significant cause of morbidity and can be challenging to manage. Among the various causes of chronic non‐healing ulcers, lymphedema is also considered a possible diagnosis in countries such as Nepal. Lymphatic filariasis has been a significant public health issue in endemic areas. Wuchereria bancrofti is a common nematode parasite that causes lymphatic filariasis. Excessive retention of lymphatic fluid in the interstitial compartment can cause localized tissue swelling, known as lymphedema, which is caused by impaired lymphatic drainage. Microfilariae can be detected in peripheral blood, body fluids, and needle aspirates. Microfilaria is not commonly found in ulcers on elephantiasis legs. We discuss here a case of 73‐year‐old women with elephantiasis legs with pus discharging ulcers in the thighs. Microscopic examination of pus discharge revealed microfilaria which highlights the importance of pus examination as diagnostic modality in endemic countries. [ABSTRACT FROM AUTHOR]

Background: Few hematologic profiles for free‐ranging amphibians are available. Hematologic evaluation is a useful tool for determining the health of amphibian populations and providing further knowledge for conservation actions. Objectives: Hematologic variables and the presence and effect of hemoparasites in anuran species were evaluated in Northern Sinaloa, Mexico. Methods: Blood samples were collected from wild anurans of eight species to perform blood cell counts, leukocyte differential counts, and serum protein concentrations using manual methods and refractometry. In addition, morphologic identification and quantification of the hemoparasites were performed on blood smears. Results: Differences were observed by sex, age, and season for the hematologic values of Incilius alvarius (n = 23), Incilius mazatlanensis (n = 46), Rhinella horribilis (n = 64), Leptodactylus melanonotus (n = 46), Lithobates forreri (n = 135), Lithobates catesbeianus (n = 20), Smilisca fodiens (n = 42), and Scaphiopus couchii (n = 7). Intra‐ and extra‐erythrocytic hemoparasites were found in 56.2% of amphibian hosts; the hemoparasite infection of R. horribilis and L. melanonotus was higher in the dry season, showing increases in erythroplastids and monocytes. For L. forreri, males were more infected than females, and increases in leukocytes were associated with infections of different types of hemoparasites species. Conclusions: Hematologic values, hemoparasite prevalence, and the response to hemoparasite infection vary among amphibian species, sex, and age, as well as on season and hemoparasite type. This highlights the importance of hematologic evaluations in wild amphibian populations to determine the subclinical effects of hemoparasite infections. [ABSTRACT FROM AUTHOR]

Key Clinical Message Skin ulcerations are a significant cause of morbidity and can be challenging to manage. Among the various causes of chronic non‐healing ulcers, lymphedema is also considered a possible diagnosis in countries such as Nepal. Lymphatic filariasis has been a significant public health issue in endemic areas. Wuchereria bancrofti is a common nematode parasite that causes lymphatic filariasis. Excessive retention of lymphatic fluid in the interstitial compartment can cause localized tissue swelling, known as lymphedema, which is caused by impaired lymphatic drainage. Microfilariae can be detected in peripheral blood, body fluids, and needle aspirates. Microfilaria is not commonly found in ulcers on elephantiasis legs. We discuss here a case of 73‐year‐old women with elephantiasis legs with pus discharging ulcers in the thighs. Microscopic examination of pus discharge revealed microfilaria which highlights the importance of pus examination as diagnostic modality in endemic countries.

Background: In onchocerciasis-endemic areas with high ongoing Onchocerca volvulus transmission, a high prevalence of epilepsy has been reported. This study aimed to determine the prevalence and clinical characteristics of epilepsy in the Bono Region of Ghana following 27 years of implementation of ivermectin mass drug administration (MDA). Methods: Between October 2020 and August 2021, cross-sectional surveys were conducted in nine communities in the Tain District and Wenchi Municipality of the Bono Region of Ghana. In the first stage, a random door-to-door approach was used to screen the population for epilepsy using a pre-tested questionnaire. Persons suspected of having epilepsy were invited for a second-stage neurological examination for case verification. Community O. volvulus microfilarial infection status and Ov16 seropositivity were also determined. Ninety-five confidence intervals (95% CI) for prevalence values were calculated using the Wilson Score Interval. Results: Of the 971 participants, 500 (51.5%) were females, and the median age (interquartile range) was 26 (15‒43) years. Fourteen participants (1.4%, 95% CI: 1.0‒2.0) were diagnosed as having epilepsy with generalized seizures being the most frequent seizure type (85.7%, 12/14). The overall microfilarial prevalence of O. volvulus was 10.3% (November 2020) and 9.9% (August 2021); the Ov16 seroprevalence was 22.2% (June 2021). Only 63.2% took ivermectin in the last round of MDA distribution in March 2021. Conclusions: The 1.4% prevalence of epilepsy in the Bono region is similar to the median epilepsy prevalence in sub-Saharan Africa. However, the persistent microfilarial prevalence and low ivermectin study coverage call for the Ghana Onchocerciasis Elimination Programme to step up its efforts to ensure that the gains achieved are consolidated and improved to achieve the elimination of onchocerciasis by 2030. [ABSTRACT FROM AUTHOR]

Background: Filarial infections continue to pose a great challenge in endemic countries. One of the central goals in the fight against human filarial infections is the development of strategies that will lead to the inhibition of microfilariae (mf) transmission. Keeping mf under a certain threshold within endemic populations will stop transmission and eliminate the infection. Method: A narrative review was carried out to identify the possibilities and limitations of exploring the use of eosinophil responses as an anti‐filarial vaccine, and biomarker for the detection of filarial infections. An extensive literature search was performed in online scientific databases including PubMed Central, PubMed, BioMed Central, with the use of predefined search terms. Results: A better understanding of the parasite‐host interactions will lead to the development of improved and better treatment or vaccine strategies that could eliminate filariasis as soon as possible. Highlighted in this review is the explorative use of eosinophil‐producing CLC/Galectin‐10 as a potential biomarker for filarial infections. Also discussed are some genes, and pathways involved in eosinophil recruitments that could be explored for anti‐filarial vaccine development. Conclusion: In this short communication, we discuss how eosinophil‐regulated genes, pathways, and networks could be critical in providing more information on how reliably a front‐line immune player could be exploited for anti‐filarial vaccine development and early infection biomarker. [ABSTRACT FROM AUTHOR]

Abstract Background Filarial infections continue to pose a great challenge in endemic countries. One of the central goals in the fight against human filarial infections is the development of strategies that will lead to the inhibition of microfilariae (mf) transmission. Keeping mf under a certain threshold within endemic populations will stop transmission and eliminate the infection. Method A narrative review was carried out to identify the possibilities and limitations of exploring the use of eosinophil responses as an anti‐filarial vaccine, and biomarker for the detection of filarial infections. An extensive literature search was performed in online scientific databases including PubMed Central, PubMed, BioMed Central, with the use of predefined search terms. Results A better understanding of the parasite‐host interactions will lead to the development of improved and better treatment or vaccine strategies that could eliminate filariasis as soon as possible. Highlighted in this review is the explorative use of eosinophil‐producing CLC/Galectin‐10 as a potential biomarker for filarial infections. Also discussed are some genes, and pathways involved in eosinophil recruitments that could be explored for anti‐filarial vaccine development. Conclusion In this short communication, we discuss how eosinophil‐regulated genes, pathways, and networks could be critical in providing more information on how reliably a front‐line immune player could be exploited for anti‐filarial vaccine development and early infection biomarker.

Background: Newer generation ophthalmologists practicing in the developed world are not very familiar with some tropical ocular diseases due to the absence of reports in the ophthalmic literature over the past thirty years. Because of world globalization or due to influx of immigrants from sub-Saharan Africa, exotic retinal diseases are being encountered more often in ophthalmology clinics. Methods: A multicenter case series of chorioretinitis or optic neuritis with obscure etiology that used serial multimodal imaging. Results: Four cases qualified with the diagnosis of presumed ocular onchocerciasis based on their residence near fast rivers in endemic areas, multimodal imaging, long term follow-up showing progressive disease and negative workup for other diseases. Characteristic findings include peripapillary choroiditis with optic neuritis or atrophy, subretinal tracts of the microfilaria, progressive RPE atrophy around heavily pigmented multifocal chorioretinal lesions of varying shapes, subretinal white or crystalline dots, and response to ivermectin. Typical skin findings are often absent in such patients with chorioretinitis rendering the diagnosis more challenging. Conclusions: Familiarity with the myriad ocular findings of onchocerciasis, and a high-degree of suspicion in subjects residing in endemic areas can help in the correct diagnosis and implementation of appropriate therapy. Onchocercal chorioretinitis is a slow, insidious, progressive, and prolonged polymorphous disease.

Purpose: To study clinical and pathological features of parasitic lesions in the ocular adnexa in a tertiary care ophthalmic center in south India. Methods: 43 cases of ocular parasitosis were analysed clinically and correlated with the pathological findings (gross morphology and histopathology) over a period of five years (2015–2020). Results: Among the 43 cases, the age group ranged from 9 months to 78 years (mean age of 41.6 years). Female patients were more common than male patients, with a percentage of 63% (27) and 37% (16) respectively. Cystic lesion in the lid or orbit was seen in 23 cases (53.4%); solid mass lesions were seen in 17 cases (39.5%); subconjunctival worms in three cases; and subretinal parasite in one. Gross examination and histopathologic study showed Dirofilaria in 23 cases (53.5%), followed by Cysticercus in six cases (14%) and Microfilariae in four cases (9.3%). Exact species identification was not possible in ten cases (23.25%). Correlation between the type of lesion and type of inflammatory cells with the specific parasite was done. Conclusion: Our study showed that important clinicopathological correlations can be made from the parasitic lesions in the eye and adnexa, which can aid in definitive diagnosis and prompt identification of the parasite for patient management.

The rectangular filtering microfluidic chip was invented using microfluidics device fabrication technology and can separate living microfilariae from blood samples without a syringe pump. The diagnostic results are highly effective. The device is based on the principle of separating millions of blood cells from microfilariae using a rectangular filter structure. It disperses fluid evenly into the flow-passage channel, and its rectangular filter structure is the key to success in reducing the pressure and separating blood cells from microfilariae effectively. The flow rate and blood cell concentration were optimized in our study. The chip is intended to be a point-of-care device that can reduce the use of superfluous instrumentation in the field. The technology is designed to be rapid, accurate, and easy-to-use for all users, especially those in remote areas.

Filarial parasites are tissue dwelling worms transmitted by hematophagous vectors. Understanding the mechanisms regulating microfilariae (the parasite offspring) development is a prerequisite for controlling transmission in filarial infections. Th2 immune responses are key for building efficient anti-parasite responses but have been shown to also lead to detrimental tissue damage in the presence of microfilariae. Litomosoides sigmodontis, a rodent filaria residing in the pleural cavity was therefore used to characterize pleuropulmonary pathology and associated immune responses in wild-type and Th2 deficient mice. Wild-type and Th2-deficient mice (Il-4ra-/-/Il-5-/-) were infected with L. sigmodontis and parasite outcome was analyzed during the patent phase (when microfilariae are in the general circulation). Pleuropulmonary manifestations were investigated and pleural and bronchoalveolar cells were characterized by RNA analysis, imaging and/or flow cytometry focusing on macrophages. Il-4ra-/-/Il-5-/- mice were hypermicrofilaremic and showed an enhanced filarial survival but also displayed a drastic reduction of microfilaria-driven pleural cavity pathologies. In parallel, pleural macrophages from Il-4ra-/-/Il-5-/- mice lacked expression of prototypical alternative activation markers RELMa and Chil3 and showed an altered balance of some markers of the arginine metabolic pathway. In addition, monocytes-derived F4/80intermediate macrophages from infected Il- 4ra-/-/Il-5-/- mice failed to mature into resident F4/80high large macrophages. Altogether these data emphasize that the presence of both microfilariae and IL- 4R/IL-5 signaling are critical in the development of the pathology and in the phenotype of macrophages. In Il-4ra-/-/Il-5-/- mice, the balance is in favor of parasite development while limiting the pathology associated with the host immune response. [ABSTRACT FROM AUTHOR]

Filarial parasites are tissue dwelling worms transmitted by hematophagous vectors. Understanding the mechanisms regulating microfilariae (the parasite offspring) development is a prerequisite for controlling transmission in filarial infections. Th2 immune responses are key for building efficient anti-parasite responses but have been shown to also lead to detrimental tissue damage in the presence of microfilariae. Litomosoides sigmodontis, a rodent filaria residing in the pleural cavity was therefore used to characterize pleuropulmonary pathology and associated immune responses in wild-type and Th2 deficient mice. Wild-type and Th2-deficient mice (Il-4rα-/-/Il-5-/-) were infected with L. sigmodontis and parasite outcome was analyzed during the patent phase (when microfilariae are in the general circulation). Pleuropulmonary manifestations were investigated and pleural and bronchoalveolar cells were characterized by RNA analysis, imaging and/or flow cytometry focusing on macrophages. Il-4rα-/-/Il-5-/- mice were hypermicrofilaremic and showed an enhanced filarial survival but also displayed a drastic reduction of microfilaria-driven pleural cavity pathologies. In parallel, pleural macrophages from Il-4rα-/-/Il-5-/- mice lacked expression of prototypical alternative activation markers RELMα and Chil3 and showed an altered balance of some markers of the arginine metabolic pathway. In addition, monocytes-derived F4/80intermediate macrophages from infected Il-4rα-/-/Il-5-/- mice failed to mature into resident F4/80high large macrophages. Altogether these data emphasize that the presence of both microfilariae and IL-4R/IL-5 signaling are critical in the development of the pathology and in the phenotype of macrophages. In Il-4rα-/-/Il-5-/- mice, the balance is in favor of parasite development while limiting the pathology associated with the host immune response.

Loa loa microfilariae were found on thick blood smears (TBSs) from 8 of 300 (2.7%) residents of Bioko Island, Equatorial Guinea, during a Plasmodium falciparum sporozoite malaria vaccine clinical trial. Only one subject was found to have microfilaraemia on his first exam; parasites were not discovered in the other seven until subsequent TBSs were performed, at times many weeks into the study. All infected individuals were asymptomatic, and were offered treatment with diethylcarbamazine, per national guidelines. L. loa microfilaraemia complicated the enrolment or continued participation of these eight trial subjects, and only one was able to complete all study procedures. If ruling out loiasis is deemed to be important during clinical trials, tests that are more sensitive than TBSs should be performed. [ABSTRACT FROM AUTHOR]

Filarial parasite infestation not only affects the structure and function of lymphatic vessels but is also associated with extralymphatic pathology and disease. Incidence of renal involvement in microfilaria carriers has led to increased cognizance of extralymphatic presentation. Literature set forth clinical syndromes having extralymphatic manifestation of filaria. The diagnosis of filariasis is done by visualisation of microfilaria in peripheral blood smear, lymphatic tissue. Other modalities of diagnosis are Enzyme linked immunosorbent assay (ELISA), Immunochromatographic test. Diethyl carbamazine (DEC) provocation test usually is done to detect microfilaria in night blood smear due to the nocturnal periodicity of microfilaria. The drug DEC flushes the microfilaria into the peripheral circulation leading to high probability of detection. We present a case of a 59-year-old male who was diagnosed as nephrotic syndrome and after a DEC challenge we detected microfilaria in the peripheral smear confirming microfilaria-induced Nephrotic Syndrome after all other secondary conditions were excluded. [ABSTRACT FROM AUTHOR]

Background and Aim: Filarial infections can significantly impact the health of both humans and animals. In elephants, filariasis has been associated with cutaneous dermatitis and skin nodules. However, molecular evidence for such infections is limited in Thailand. This study aimed to identify the morphological and molecular characteristics of microfilaria in captive Asian elephants in Thailand. Materials and Methods: Whole blood collected from the ear vein of 129 captive Asian elephants was hematologically analyzed, and the blood parasites were evaluated using three standard techniques: The microcapillary test, thin blood smears, and polymerase chain reaction (PCR). Results: Conventional PCR revealed that approximately 17% (22/129) of the sampled elephants were positive for microfilaria. Microscopy revealed that microfilariae are large, unsheathed, with extended nuclei, a short headspace, and a curved tail tapering at the end. Results of internal transcribed spacer region analysis show that the elephant microfilariae are closely related to Onchocerca spp. All of the elephants positive for microfilaria presented with neither skin lesion nor anemic signs. Microfilaria infection was not associated with age; however, microfilariae were more likely to be detected in male elephants due to differences in management systems. Conclusion: This is the first study to provide both morphological and molecular evidence of microfilaria in Thai elephants. There is an urgent need to investigate the long-term and large-scale effects of microfilaria on the health of elephants.

Abstract Background Various heartworm (HW) diagnostic testing modalities detect products of, or reactions to, different life cycle stages of Dirofilaria immitis. Microfilariae (Mf) can be directly visualized in blood, antigen (Ag) from immature and adult heartworms may be detected on commercial assays, and antibody (Ab) tests detect the host immune response to larval stages. Ag and Mf tests are commonly used in dogs, which frequently carry adult HW infections, but Ab tests have only been validated for use in cats. In some HW-infected dogs, Ag is blocked by immune complexing leading to false-negative results. Heat-treatment (HT) to disrupt these complexes can increase the sensitivity of HW Ag tests. The aim of this study was to compare different methods for diagnosing HW infection in dogs at high risk using individual and paired diagnostic tests, including an exploration of using Ab tests designed for cats to test canine samples. Methods One hundred stray adult (≥ 2-year-old) dogs in Florida shelters were tested using Mf, HW Ag, and HW Ab tests (feline HW Ab tests currently not commercially validated/approved for use in dogs); two versions of each test platform were used. Results Fourteen dogs tested positive using point-of-care (POC) Ag tests; an additional 2 dogs tested positive with microtiter well assay, and an additional 12 dogs tested positive using HT Ag testing. For individual tests, Ag test sensitivity/specificity compared to HT Ag was 50–57%/100%, and Ab tests were 46–64%/82–94%. Sensitivity estimates for individual tests were higher when comparing to non-HT Ag. Pairing POC Ag tests with Mf tests improved sensitivity without loss of specificity, while pairing POC Ag and Ab tests modestly increased sensitivity at the expense of specificity. Conclusions Screening dogs for HW infection using both POC Ag and Mf detection, which is recommended by the American Heartworm Society, improved diagnostic performance in this study compared to single Ag test use, but may have missed more than one in four infected dogs. The need to improve access to highly accurate, rapid, and inexpensive large-scale HW testing for dogs in animal shelters remains largely unmet by current testing availability. The development of practical and validated protocols that incorporate heat or chemical treatment to disrupt Ag-Ab complexes in POC testing or decreasing the cost and time required for such testing in reference laboratories might provide solutions to this unmet need. Similar studies performed in countries where the prevalence of parasites such as D. repens or A. vasorum is different to the USA could potentially yield very different positive predictive values for both HT and non-HT Ag tests. Graphic abstract

Abstract Background Blood parasites have been the subject of much research, with numerous reports of the presence of microfilariae in the peripheral blood (circulating microfilariae) of birds belonging to many orders. Current limitations in molecular characterization methods and species identification using morphological characters of circulating microfilariae are major obstacles to improving our understanding the biology of Filarioidea species, particularly in wildlife. The aim of this study was to partially fill these gaps, with particular emphasis on morphological features of microfilariae, which are the most readily accessible stages of these pathogens. Methods Peripheral blood samples of 206 birds belonging to genera Acrocephalus (five species) and Sylvia (five species) were examined using the buffy coat method to process the blood samples for the presence of microfilariae. Positive birds were dissected to collect adult nematodes. Microfilariae and adult nematodes were described, and sequences of their mitochondrial cytochrome c oxidase subunit I and nuclear 28S rDNA gene fragments were obtained and used for molecular characterization and Bayesian phylogenetic inferences. Results Overall prevalence of microfilariae was 2.9%. Microfilariae were found in the blood samples from six birds (2 Acrocephalus scirpaceus and 1 each of A. arundinaceus, Sylvia atricapilla, S. borin and S. curruca), which were dissected. All parasite species observed were new. Eufilaria acrocephalusi sp. n. and Eufilaria sylviae sp. n. were present in subcutaneous, peritracheal and periesophageal connective tissues in A. scirpaceus and S. borin, respectively. Splendidofilaria bartletti sp. n. was found in finger joins of S. atricapilla. Illustrations of microfilariae and adult nematodes are shown, and morphological and phylogenetic analyses identified the DNA barcode haplotypes that are associated with these species. Phylogenetic analysis places the parasites of different genera in different closely related clades. Conclusions Adult nematode morphological characters, which have been traditionally used in the taxonomy of Filarioidea species, have a phylogenetic value. Importantly, in our study parasites of different genera were readily distinguishable based on the morphology of their microfilariae. The link between molecular and morphology data requires more study in Filarioidea species research, particularly because this approach provides new knowledge on species identity using only readily accessible blood stages (microfilariae), thereby avoiding host dissection and thus minimizing harm to wildlife during research.

Purpose: To study clinical and pathological features of parasitic lesions in the ocular adnexa in a tertiary care ophthalmic center in south India.Methods: 43 cases of ocular parasitosis were analysed clinically and correlated with the pathological findings (gross morphology and histopathology) over a period of five years (2015-2020).Results: Among the 43 cases, the age group ranged from 9 months to 78 years (mean age of 41.6 years). Female patients were more common than male patients, with a percentage of 63% (27) and 37% (16) respectively. Cystic lesion in the lid or orbit was seen in 23 cases (53.4%); solid mass lesions were seen in 17 cases (39.5%); subconjunctival worms in three cases; and subretinal parasite in one. Gross examination and histopathologic study showed Dirofilaria in 23 cases (53.5%), followed by Cysticercus in six cases (14%) and Microfilariae in four cases (9.3%). Exact species identification was not possible in ten cases (23.25%). Correlation between the type of lesion and type of inflammatory cells with the specific parasite was done.Conclusion: Our study showed that important clinicopathological correlations can be made from the parasitic lesions in the eye and adnexa, which can aid in definitive diagnosis and prompt identification of the parasite for patient management. [ABSTRACT FROM AUTHOR]

The prevalence of haemoparasites among blood donors in the studied area has not been previously documented. This study determined the prevalence of syphilis and haemoparasitic infections among blood donors in Calabar, Cross River State, Nigeria. This was a hospital-based cross-sectional study involving 200 consenting blood donors. Samples were processed using the Venereal Disease Research Laboratory (VDRL) screening technique for the detection of Treponema pallidum antibodies. Screening for microfilaria was conducted using Knott's concentration technique. Thick and thin blood films stained with 3% Giemsa solution were examined to confirm the presence of malaria parasites. All the 200 blood donors harboured trophozoites of Plasmodium falciparum, with low parasite counts per millilitre of blood. One hundred and thirteen (56.5%) blood donors had microfilaria Loa. 21(10.5%) blood donors were positive for antibodies homologous to T. pallidum antigens. Mixed infections of P. falciparum + Microfilaria; P. falciparum + Microfilaria + T. pallidum and Microfilaria + T. pallidum occurred at the prevalence rates of 50%, 16.5% and 4%, respectively. The prevalence of haemoparasites was higher among male blood donors than in their female counterparts. The most prevalent infection based on the frequency of blood donation was the malaria parasite (45.5%). Among the first-time blood donors, the most prevalent infections were malaria (54.5%) and Loa loa (24.5%). This study has shown a significantly (p < 0.05) high prevalence of malaria parasite and Loa loa infection in the studied group, it also showed malaria parasite and Loa loa as the major haemoparasites found among blood donors in the health institution studied. [ABSTRACT FROM AUTHOR]

Purpose: The occurrence of Single-Nucleotide Polymorphisms (SNPs) associated with repeated ivermectin treatment and sub-optimal responses reported by previous findings is of great concern in Onchocerciasis endemic areas. This study investigated SNPs' occurrence after 15 years of ivermectin intervention in Onchocerciasis endemic communities in two Local Government Areas of Taraba State, Nigeria. Methods: Microfilariae samples were collected by skin snip from individuals treated with ivermectin for 10–15 years of annual distribution and preserved in RNAlater® in a 1.5 ml micro-centrifuge tube. Genomic DNA was extracted from microfilariae and residual skin, amplification in two regions within the β-tubulin gene, sequenced and analyzed for SNPs using Bioinformatics tools. Results: Three distinct SNP positions: 1183 (T/G), 1188 (T/C) and 1308 (C/T) on the β-tubulin gene on the targeted 1083–1568 bp fragment, associate's with the ivermectin-treated population. Furthermore, SNPs positions detected in this study are 1730 (A/G) and 1794 (T/G) in the β-tub gene in the 1557–1857 (bp) region. The 1794 (T/G) SNP position (Phe243Val) in the exon within the β-tubulin gene region were observed in this study. Conclusion: The present study indicates that SNPs are observed in Onchocerca volvulus, thus strengthening the warning that genetic changes could occur in some parasite populations in some ivermectin-treated areas. [ABSTRACT FROM AUTHOR]

Abstract Background Current measures for the prevention of dirofilariasis, caused by the dog heartworm, Dirofilaria immitis, rely on macrocyclic lactones, but evidence of drug-resistant isolates has called for alternative approaches to disease intervention. As microfilariae are known to be in a state of developmental arrest in their mammalian host and then undergo two molts once inside the arthropod, the aim of this study was to look at the developmental regulation of D. immitis microfilariae that occurs in their arthropod host using in vitro approaches and to investigate the role of the ecdysone signaling system in this development regulation. Methods Dirofilaria immitis microfilariae extracted from dog blood were incubated under various culture conditions to identify those most suitable for in vitro culture and development of the microfilariae, and to determine the effects of fetal bovine serum (FBS), mosquito cells, and ecdysteroid on the development of the microfilariae. Transcript levels of the ecdysone signaling pathway components were measured with droplet digital PCR (ddPCR). Results In vitro conditions that best promote early development of D. immitis microfilariae to the “late sausage stage” have been identified, although shedding of the cuticle was not observed. FBS had inhibitory effects on the development and motility of the microfilariae, but media conditioned with Anopheles gambiae cells were favorable to microfilarial growth. The transcript level study using ddPCR also showed that ecdysone signaling system components were upregulated in developing microfilariae and that 20-hydroxyecdysone increased the proportion of larvae developing to the sausage and late sausage stages in vitro. Conclusions The arthropod host environment provides cues required for the rapid development of D. immitis microfilariae, and the ecdysone signaling system may play an important role in filarial nematode developmental transitions. This study contributes to a better understanding of the developmental process of D. immitis microfilariae.

India has 40% of world's lymphatic filariasis (LF) cases. Thread like adult parasites reside in afferent lymphatics and may remain viable for more than two decades. Males have a substantial 13.67% greater rate of LF-related disease overall than females. Cases have been reported from 20 states and union territories (UT) of India. A 55-year-old postmenopausal female, presented with complaints of swelling over the vulval region with itching since 25 years. She had history of elephantiasis of lower limbs and inguinal swellings for which she was operated and medically treated 30 years back. On local examination, swelling was present on labia majora bilaterally affecting left more than right. The swelling was Arm in consistency, nonreducible, noncompressible, no impulse present on coughing, nonfluctuant and no nodularity was felt inside the swellings. The overlying skin was excoriated, thickened, nontender and pigmented. Provisional diagnosis of vulval fllariasis was made. Midnight peripheral smear for microfilaria (MF) was negative. Excisional biopsy of bilateral vulval swelling with primary repair was done. Postoperative period was uneventful and histopathology report of mass was consistent with vulval fllariasis. Filarial Antigen and PCR based assay for DNA are other tests for LF. High frequency ultrasound and Doppler identifies motile adult worm within dilated lymphatics known as Filarial Dance Sign. Aims of management of vulval fllariasis is reduction of vulval swelling by cosmetic surgery, prevention of secondary infections and restoration of normal genital and sexual functions. Vulval elephantiasis is very rare especially in a nonendemic district resident and it is always a clinical diagnosis of exclusion. [ABSTRACT FROM AUTHOR]

Filariasis is a vector borne disease commonly found in tropical countries like India. Causative agent for this is Wuchereria Bancrofti. This paper presents report of the microfilaria in endometrial histopathology in a 35-year-old reproductive age female presenting with incomplete abortion with vaginal bleeding. There is hardly any case report with similar presentation. Endemicity of the disease is one of the associated factors. [ABSTRACT FROM AUTHOR]

Abstract Background Pulmonary manifestations are regularly reported in both human and animal filariasis. In human filariasis, the main known lung manifestations are the tropical pulmonary eosinophilia syndrome. Its duration and severity are correlated with the presence of microfilariae. Litomosoides sigmodontis is a filarial parasite residing in the pleural cavity of rodents. This model is widely used to understand the immune mechanisms that are established during infection and for the screening of therapeutic molecules. Some pulmonary manifestations during the patent phase of infection with L. sigmodontis have been described in different rodent hosts more or less permissive to infection. Methods Here, the permissive Mongolian gerbil (Meriones unguiculatus) was infected with L. sigmodontis. Prevalence and density of microfilariae and adult parasites were evaluated. Lungs were analyzed for pathological signatures using immunohistochemistry and 3D imaging techniques (two-photon and light sheet microscopy). Results Microfilaremia in gerbils was correlated with parasite load, as amicrofilaremic individuals had fewer parasites in their pleural cavities. Fibrotic polypoid structures were observed on both pleurae of infected gerbils. Polyps were of variable size and developed from the visceral mesothelium over the entire pleura. The larger polyps were vascularized and strongly infiltrated by immune cells such as eosinophils, macrophages or lymphocytes. The formation of these structures was induced by the presence of adult filariae since small and rare polyps were observed before patency, but they were exacerbated by the presence of gravid females and microfilariae. Conclusions Altogether, these data emphasize the role of host-specific factors in the pathogenesis of filarial infections.

We present a case report of periocular Loa loa. The key feature of L. loa distinguishing it from other human filarial parasites are cuticular bosses, which are presented in images from a light microscope and a scanning electron microscope. The cuticular bosses could be divided into three subtypes not previously described.