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The main human echinococcal infections are caused by Echinococcus granulosus sensu lato, which causes cystic echinococcosis (CE), and E. multilocularis, which causes alveolar echinococcosis (AE). The parasites have different life [...]

Background: Infection with the filarial nematode Loa loa, endemic in Central and Western Africa, has been associated with increased morbidity and mortality. A number of reports described the presence of spleen nodules, originating from degenerating microfilariae, in humans and animals infected with L. loa. The long-term consequences of this process on individuals chronically exposed to infection in terms of spleen function and possible link with excess mortality are unknown. The aim of this study was to evaluate the prevalence of focal spleen lesions, their evolution over time, and markers of spleen function, in individuals with L. loa infection living in highly endemic areas of Gabon. Methodology/principal findings: This was a cross-sectional study followed by a longitudinal study of the subset of individuals with spleen nodules. Two hundred sixteen participants from Ngounié and Moyen-Ogooué provinces of Gabon, reporting a history of eyeworm migration and/or Calabar swelling, were included. Participants were categorized into infected microfilaraemic with low (N = 74) and high (N = 10) microfilaraemia, and symptomatic amicrofilaraemic (N = 132), based on blood microscopy. Howell-Jolly bodies in erythrocytes, as indirect marker of spleen functional impairment, were within normal ranges. On ultrasound, no evident signs of spleen fibrosis or hypotrophy were observed. Multiple spleen hypoechoic centimetric macronodules were observed in 3/216 participants (1.4%), all with microfilaraemic L. loa infection (3.4% of microfilaraemics); macrondules disappeared at the 6-months follow-up examination in 2/3 individuals. Spleen hypoechoic micronodules, persisting at the 6-months follow-up, were detected in 3/216 participants (1.4%), who were all amicrofilaraemic. Conclusions/significance: Transitory spleen macronodules are present in a small but consistent proportion of individuals with microfilaraemic loiasis, appearing a rather benign phenomenon in terms of impact on spleen morphology and function. Their occurrence should be taken into consideration to avoid misdiagnosis and mistreatment. Prevalence and significance of spleen micronodular ultrasound patterns in the general population would be also worth evaluating. Author summary: Loa loa is a vector borne, filarial worm affecting an estimated 20 million people in Central and West Africa. Long considered a benign infection, more recently it has been associated with substantial morbidity and increased mortality in individuals with high L. loa microfilaraemia, prompted to reconsider the importance this infection and investigate the potential pathophysiological mechanisms. The spleen has a central role in the response to pathogens, including parasites; therefore, its dysfunction may lead to an increase in the risk and severity of infectious diseases, which might contribute to the observed excess mortality in hypermicrofilaremic loiasis. The presence of spleen centimetric nodules, originating from degradation of microfilariae, in humans and animals infected with L. loa, has been described, but the long-term consequences of this process on individuals chronically exposed to infection in terms of spleen function are unknown. In this study performed in individuals with L. loa infection living in highly endemic areas of Gabon, we found a prevalence of 3.4% spleen nodules in microfilaraemic participants, while no such lesions were observed in symptomatic amicrofilaraemic participants. Nodules were transitory and appeared to be a rather benign phenomenon in terms of impact on spleen morphology and function. [ABSTRACT FROM AUTHOR]

Human cystic echinococcosis (CE) is a parasitic infection caused by the larval stage of the tapeworm Echinococcus granulosus sensu lato, primarily affecting the liver and lungs. Although the heart is affected in only 0.02–2% of all CE cases, a considerable number of cases have been, and continue to be, published. However, due to the rare occurrence of cardiac CE and the resulting lack of clinical trials, knowledge about various aspects of the disease remains limited. To obtain a clearer picture of anatomical, clinical, diagnostic as well as therapeutic aspects of cardiac CE, we systematically reviewed the literature published between 1965 and 2022. The anatomical pattern of the affected cardiac structures follows the extension of the supplying capillary bed. The majority of patients (82.7%) are symptomatic and present with prolonged non-specific symptoms such as dyspnoea, chest pain and palpitations. Acute complications generally derive from cyst rupture, occur in 18.3% of cases and manifest as embolism, pericardial tamponade, or anaphylactic reaction in 83.2%, 17.8% and 10.9% of these cases, respectively. As for CE cysts localized in other organs, the diagnosis of cardiac CE is made by imaging. Serology plays a minor role due to its limited sensitivity. Unlike abdominal CE cysts, cardiac CE cysts are usually resected independent of their stage (active/inactive), because their presence impairs cardiac performance and carries the risk of long-term sequelae. More than 80% of patients are treated with a single surgical intervention. We found a disease-related case fatality rate of 11.1%. Since local recurrence was reported up to 108 months and secondary CE up to 72 months after surgery, patients should be followed up for a minimum of 10 years. Author summary: Human cystic echinococcosis (CE) is a parasitic infection caused by the larva of the dog tapeworm Echinococcus granulosus, which primarily affects the liver and lungs. Although the heart is rarely affected (≤2% of cases), a considerable number of case reports continue to be published. While the diagnostic and clinical management of cardiac CE has greatly benefited from the increasingly widespread availability of diagnostic imaging techniques as well as from advances in heart surgery, the overall picture of cardiac CE remains patchy and several aspects remain poorly understood. To overcome this, we systematically reviewed the last five decades of published literature on cardiac CE, and analyzed and summarized the existing data. [ABSTRACT FROM AUTHOR]

The World Health Organization has started a process to issue guidelines for the control of strongyloidiasis. The guidelines might recommend to implement preventive chemotherapy (PC) at community level (i.e. to all individuals above 5 years of age), over a defined prevalence threshold. We previously estimated the number of school-age children (SAC) who would need PC. Here we estimate the number of people above 15 years of age who might be included in PC for strongyloidiasis. Based on previous Strongyloides prevalence estimates and on countries' age distribution, we retrieved the number of adults in need of PC. We then subtracted the number of people already involved in ivermectin mass distribution for the elimination of onchocerciasis and lymphatic filariasis and people living in countries where Loa loa is endemic. The number of adults to be involved in PC was estimated at 905.4 (95% confidence interval (CI): 520.6–1177.2), 660.2 (95% CI: 512.7-1214.9), and 512.1 (95% CI: 276–719.4) million people, when the strongyloidiasis prevalence threshold for implementing PC was set to 10%, 15% and 20%, respectively. Estimates at country level are also provided.These estimates might help endemic countries wishing to implement PC for strongyloidiasis to allocate resources to include adults in addition to SAC in control programmes. This article is part of the Theo Murphy meeting issue 'Strongyloides: omics to worm-free populations'. [ABSTRACT FROM AUTHOR]

Loa loa is a filarial nematode transmitted by tabanid flies of the genus Chrysops, which inhabits forested areas of West and Central Africa (1). It is estimated that >10 million [...]

Echinococcoses require the involvement of specialists from nearly all disciplines; standardization of the terminology used in the field is thus crucial. To harmonize echinococcosis terminology on sound scientific and linguistic grounds, the World Association of Echinococcosis launched a Formal Consensus process. Under the coordination of a Steering and Writing Group (SWG), a Consultation and Rating Group (CRG) had the main missions of (1) providing input on the list of terms drafted by the SWG, taking into account the available literature and the participants’ experience; and (2) providing independent rating on all debated terms submitted to vote. The mission of the Reading and Review Group (RRG) was to give an opinion about the recommendation paper in terms of readability, acceptability and applicability. The main achievements of this process were: (1) an update of the current nomenclature of Echinococcus spp.; (2) an agreement on three names of diseases due to Echinococcus spp.: Cystic Echinococcosis (CE), Alveolar Echinococcosis (AE) and Neotropical Echinococcosis (NE), and the exclusion of all other names; (3) an agreement on the restricted use of the adjective “hydatid” to refer to the cyst and fluid due to E. granulosus sensu lato; and (4) an agreement on a standardized description of the surgical operations for CE, according to the “Approach, cyst Opening, Resection, and Completeness” (AORC) framework. In addition, 95 “approved” and 60 “rejected” terms were listed. The recommendations provided in this paper will be applicable to scientific publications in English and communication with professionals. They will be used for translation into other languages spoken in endemic countries.