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Background: The roundworm Ascaris suum is one of the parasites with the greatest economic impact on pig farming. In this context, lower weight gain is hypothesized to be due to decreased nutrient absorption. This study aims at characterizing the effects of A. suum infection on intestinal nutrient transport processes and potential molecular mechanisms., Methods: Three groups of six piglets each were infected orally (10,000 embryonated A. suum eggs) in a single dose ("single infection"). Another three groups were infected orally (1000 embryonated eggs) for 10 consecutive days ("trickle infection"). Animals were necropsied 21, 35 and 49 days post-infection (dpi). Three groups served as respective controls. The Ussing chamber technique was applied for the functional characterization of small intestinal tissues [short-circuit currents (I sc ) as induced by glucose, alanine and peptides; 3 H-glucose net flux rates; tissue conductance (G t )]. Transcription and expression levels of relevant cytokines and nutrient transporters were evaluated (qPCR/western blot)., Results: Peptide- and alanine-induced changes in I sc were significantly decreased in the jejunum and ileum of the trickle-infected group at 49 dpi and in the ileum of the single-infected group at 49 dpi. No significant differences regarding glucose transport were observed between the Ascaris-infected groups and the control group in Ussing chamber experiments. Transcription levels of the glucose and peptide transporters as well as of selected transcription factors (transcription of signal transducer and activator of transcription 6 [STAT6] and hypoxia-inducible factor 1-alpha [Hif-1α]) were significantly increased in response to both infection types after some periods. The transcription of interleukins 4 and 13 varied between decrease and increase regarding the respective time points, as did the protein expression of glucose transporters. The expression of the peptide transporter PepT1 was significantly decreased in the ileal single-infected group at 35 dpi. Hif-1α was significantly increased in the ileal tissue from the single-infected group at 21 dpi and in the trickle-infected group at 35 dpi. The expression levels of Na + /K + -ATPase and ASCT1 remained unaffected., Conclusions: In contrast to the current hypothesis, these results indicate that the nutrient deprivation induced by A. suum cannot be explained by transcriptional or expression changes alone and requires further studies., (© 2021. The Author(s).)

Trichuriasis and ascariasis are neglected tropical diseases caused by the gastrointestinal dwelling nematodes Trichuris trichiura (a whipworm) and Ascaris lumbricoides (a roundworm), respectively. Both parasites are staggeringly prevalent, particularly in tropical and subtropical areas, and are associated with substantial morbidity. Infection is initiated by ingestion of infective eggs, which hatch in the intestine. Thereafter, T. trichiura larvae moult within intestinal epithelial cells, with adult worms embedded in a partially intracellular niche in the large intestine, whereas A. lumbricoides larvae penetrate the gut mucosa and migrate through the liver and lungs before returning to the lumen of the small intestine, where adult worms dwell. Both species elicit type 2 anti-parasite immunity. Diagnosis is typically based on clinical presentation (gastrointestinal symptoms and inflammation) and the detection of eggs or parasite DNA in the faeces. Prevention and treatment strategies rely on periodic mass drug administration (generally with albendazole or mebendazole) to at-risk populations and improvements in water, sanitation and hygiene. The effectiveness of drug treatment is very high for A. lumbricoides infections, whereas cure rates for T. trichiura infections are low. Novel anthelminthic drugs are needed, together with vaccine development and tools for diagnosis and assessment of parasite control in the field.

Background: Ascariasis is the leading helminthic infection worldwide, with its peak prevalence noted in children aged 2-10 years. Although mainly asymptomatic, chronic and heavy infestation could lead to severe complications such as malnutrition, poor physical and cognitive development, as well as intestinal obstruction. We report the case of a 4-year-old boy with intestinal obstruction due to Ascaris lumbricoides infestation and discuss its public health significance., Case Presentation: A 4-year-old Black African boy from the Menchum Division in the Northwest Region of Cameroon, with no history of deworming since birth, presented with a 3-day history of generalized abdominal pains, vomiting and obstipation, and abdominal distention evolving over a period of 6 months. Clinical and paraclinical findings were in favor of a subacute intestinal occlusion associated with an electrolyte imbalance. An exploratory laparotomy was done after correction of the electrolyte imbalance. Perioperative findings revealed a dilated small bowel obstructed by bundles of live worms. An enterotomy of 2 cm in length was done, and the bundles of Ascaris lumbricoides worms extracted manually and by milking through the stoma. His postoperative period was unremarkable, and he was discharged on postoperative day 7. He and his entire household were dewormed with a single dose of mebendazole 500 mg administered orally. A follow-up visit 1 week after discharge revealed a healed abdominal wound and normal bowel functions., Conclusion: Despite considerable progress made on the control of soil-transmitted helminthiasis in Cameroon, the program faces a number of bottlenecks. Funding is inadequate, making data acquisition and hence remapping of high-risk zones difficult. Accessibility to enclaved zones where most high-risk children live is difficult, while community sensitization on soil-transmitted helminthiasis and proper education on the right environmental hygienic practices are lacking. All these challenges once addressed could go a long way to help achieve recently set sustainable development goals.

Ascaris lumbricoides (roundworm) is the most common helminth infection globally and a cause of lifelong morbidity that may include allergic airway disease, an asthma phenotype. We hypothesize that Ascaris larval migration through the lungs leads to persistent airway hyperresponsiveness (AHR) and type 2 inflammatory lung pathology despite resolution of infection that resembles allergic airway disease. Mice were infected with Ascaris by oral gavage. Lung AHR was measured by plethysmography and histopathology with hematoxylin and eosin (H&E) and periodic acid-Schiff (PAS) stains, and cytokine concentrations were measured by using Luminex Magpix. Ascaris -infected mice were compared to controls or mice with allergic airway disease induced by ovalbumin (OVA) sensitization and challenge (OVA/OVA). Ascaris -infected mice developed profound AHR starting at day 8 postinfection (p.i.), peaking at day 12 p.i. and persisting through day 21 p.i., despite resolution of infection, which was significantly increased compared to controls and OVA/OVA mice. Ascaris -infected mice had a robust type 2 cytokine response in both the bronchoalveolar lavage (BAL) fluid and lung tissue, similar to that of the OVA/OVA mice, including interleukin-4 (IL-4) ( P  < 0.01 and P < 0.01, respectively), IL-5 ( P  < 0.001 and P  < 0.001), and IL-13 ( P  < 0.001 and P  < 0.01), compared to controls. By histopathology, Ascaris -infected mice demonstrated early airway remodeling similar to, but more profound than, that in OVA/OVA mice. We found that Ascaris larval migration causes significant pulmonary damage, including AHR and type 2 inflammatory lung pathology that resembles an extreme form of allergic airway disease. Our findings indicate that ascariasis may be an important cause of allergic airway disease in regions of endemicity., (Copyright © 2018 American Society for Microbiology.)

Ascaris is a common cause of acute pancreatitis in developing countries. The mechanism of ascariasis induced acute pancreatitis include obstruction of papilla of Vater, invasion of common bile duct, or pancreatic duct (PD). PD ascariasis is a rare diagnosis. Endoscopic ultrasound is a highly accurate method to diagnose the aetiology of idiopathic acute pancreatitis with reference to biliary and pancreatic ascariasis. Treatment usually consist of endoscopic removal of worms with dormia basket or forceps on side viewing endoscopy. Ascaris induced pancreatitis is generally mild and worm extraction is associated with rapid relief of symptoms. We present a case of PD ascariasis diagnosed on endoscopic ultrasound., (Copyright © 2018 Pan-Arab Association of Gastroenterology. Published by Elsevier B.V. All rights reserved.)

Background: Ascaris lumbricoides is one of the most common intestinal infections in developing countries, including Kosovo. In contrast to migration to the bile duct, migration of the worm to the gallbladder, due to the narrow and tortuous nature of the cystic duct, is rare. When it does occur, it incites acalculous cholecystitis., Case Presentations: This case series describes a 16-month-old Albanian girl, a 22-month-old Albanian girl, a 4-year-old Albanian girl, and a 10-year-old Albanian boy. Here we report our experience with gallbladder ascariasis including clinical manifestations, diagnostic procedures, and treatment. Fever, diarrhea and vomiting, dehydration, pale appearance, and weakness were the manifestations of the primary disease. In all patients, a physical examination revealed reduced turgor and elasticity of the skin. Abdomen was at the level of the chest, soft, with minimal palpatory pain. The liver and spleen were not palpable. A laboratory examination was not specific except for eosinophilia. There were no pathogenic bacteria in coproculture but Ascaris was found in all patients. At an ultrasound examination in all cases we found single, long, linear echogenic structure without acoustic shadowing containing a central, longitudinal anechoic tube with characteristic movement within the gallbladder. Edema of the gallbladder wall was suggestive of associated inflammation. There were no other findings on adjacent structures and organs. All patients received mebendazole 100 mg twice a day for 3 days. They also received symptomatic therapy for gastroenteritis. Because of elevated markers of inflammation all patients were treated with antibiotics, assuming acute cholecystitis, although ultrasound was able to confirm cholecystitis in only two of our four patients. Since the length of stay was dependent on the primary pathology it was 7 to 10 days. At control ultrasounds on 14th day, third and sixth month, all patients were free of ascariasis., Conclusions: Gallbladder ascariasis should be considered in all patients presenting with abdominal pain, distension, colic, nausea, anorexia, and intermittent diarrhea associated with jaundice, nausea, vomiting, fever, and severe radiating pain. Eosinophilia, ova, and parasites on stool examination as well as an anechogenic tube with characteristic movement within the bile duct found on abdominal ultrasound are conclusive for diagnosis. Mebendazole is an effective drug for the treatment. Surgical treatment is rarely needed.

The of antihelmintic preparation albendazole using in the complex treatment of patients with chronic pancreatitis with the concomitant ascaridosis was promote regression of clinical demonstration of basic and concomitant diseases (P < 0.05). Options of coprogram and the structural state of pancreas from data of ultrasonography in marks by Marseille-Cambridge classification of chronic pancreatitis, after the conducted treatment became the better (P < 0.05), that established expedience of the use of albendazole in complex treatment of patients with a chronic pancreatitis with a concomitant ascaridosis.

Hepatobiliary ascariasis is common in developing countries where there is a low standard of public health and hygiene. We are reporting a rare case of ascariasis which induced multiple liver abscesses in a post menopausal woman who presented with fever, anorexia, nausea, vomiting and mild hepatomegaly. Ultrasonography revealed biliary ascariasis with multiple hepatic abscesses. Laparoscopic drainage of hepatic abscesses was done and microscopic examination of drainage materials showed decorticated eggs of Ascaris Lumbricoides. The post operative recovery of the patient was uneventful. Ultrasonography is a reliable modality to diagnose and follow up of such cases.

Background: It has been suggested that the proliferative capacity of cells from individuals with HIV or both HIV and helminth infections is attenuated and cytokine production is dysregulated. This study describes peripheral blood mononuclear cell proliferation capacity and cytokine profile from individuals with HIV or both HIV and helminth infections in South Africa., Methods: Forty HIV-infected and 22 HIV-uninfected participants were randomly selected and stratified into different helminth infection phenotypes by egg excretion and Ascaris lumbricoides specific -immunoglobulin-E (IgE) levels. Five day cell cultures of participants, unstimulated or stimulated with Phytohaemaglutinnin, Streptokinase, HIV-1 p24 and Ascaris lumbricoides worm antigens were stained with monoclonal antibody-fluorochrome conjugates (Ki67-FITC and CTLA-APC-4). Percentage expression of Ki67 and CTLA-4 was measured to determine cell proliferation and regulation, respectively. Culture supernatants were analysed for the expression of 13 cytokines using the Bioplex (BioRad) system. Kruskal Wallis was used to test for differences in variables between helminth infected subgroups who were either having eggs in stool and high IgE (egg+IgEhi); or eggs in stool and low IgE (egg+IgElo); or no eggs in stool and high IgE (egg-IgEhi) and those without helminth infection (egg-IgElo)., Results: Individuals excreting eggs in stool with high serum IgE (egg+IgEhi phenotype) had potent mitogen responses but consistently produced low, but statistically non-significant antigen-specific (HIV-1 p24 (p = 0.41) and Ascaris (p = 0.19) and recall antigen (Streptokinase; p = 0.31) Ki67 responses. The group also had reduced type 1 cytokines. Individuals excreting eggs in stool with low serum IgE( egg+IgElo phenotype) had a more favourable antiviral profile, characterized by higher IFNγ, IL-2, lower IL-4 and higher IL-10 production., Conclusion: The findings suggest that dual HIV/helminth infection with egg excretion and/or high Ascaris IgE phenotye may be linked with poor proliferative capacity and deleterious cytokine profile with regards to HIV control.

Background: The role of gastrointestinal infection as a factor determining vitamin B12 status in populations with low intake of animal-source foods is unclear., Objective: To determine dietary adequacy and serum concentrations of vitamin B12 in an extremely impoverished indigenous population of Panamanian children aged 12 to 60 months, and to identify predictors of both dietary and serum vitamin B12., Methods: A previous community-based survey provided the usual dietary intake and personal, household, and infection (Ascaris and diarrheal disease) information for 209 weaned children. Serum vitamin B12 was assayed using electrochemiluminescence for 65 of these children. Children with adequate or inadequate dietary vitamin B12 intake were compared, and predictors of dietary and serum vitamin B12 were identified using stepwise regression analyses of one index child per household., Results: Dietary vitamin B12 intake was inadequate in 43% of children; these children were poorer, had less frequent diarrhea, and obtained a higher percentage of their energy from carbohydrate than children with adequate intake. Energy intake positively predicted dietary vitamin B12 intake. In contrast, serum vitamin B12 concentrations were normal in all but 3% of the children. Serum vitamin B12 was positively associated with weekly servings of fruit, corn-based food, and name (a traditional starchy food), but not with animal-source foods. Finally, serum vitamin B12 was not associated with Ascaris intensity but was lowered with increasing frequency of diarrhea., Conclusions: Although inadequate dietary intake of vitamin B12 was common, most serum values were normal. Nevertheless, diarrheal disease emerged as a negative predictor of serum vitamin B12 concentration.

Scientific investigations of production losses in pigs due to roundworms are rarely conducted in commercial farms, despite the fact that this information is needed to decide whether anthelmintic treatment is cost-effective or not. Therefore, the aim of our study was to compare performance in fattening pigs treated or not treated for Ascaris suum infections. Two Danish pig farms producing fatteners and showing A. suum-induced liver white spot prevalences of 10-33% were selected for the study. In each farm, pens with fattening pigs were randomly assigned to either treatment with an anthelmintic (Flubenol, Janssen Animal Health), or a placebo. Pigs were treated by administering anthelmintic or placebo mixed in the feed for five consecutive days (5mg/kg body weight) on day 2-6 and day 36-40 after introduction to the finishing unit. Fecal egg excretion before first shipment, liver lesion scores (white spots), lean meat percentage at slaughter, average daily gain, and feed conversion were recorded weekly per pen and evaluated for the entire fattening period (30-100kg). A. suum egg excretion was detected in none of the 57 pens where pigs were treated with anthelmintic compared to 18.2% of 57 pens in the placebo group. Pen floor fecal sampling underestimated the prevalence of A. suum in the fattening units compared to individual rectal sampling; only 22% of pens where A. suum was present were diagnosed correctly by both sampling methods. The prevalence of white spots did not differ significantly between pigs treated with anthelmintic (26.7%) and pigs treated with placebo (23.7%), but considerable variation between batches and over time was observed. Liver lesion scores (none, few, moderate, many) were not significantly influenced by de-worming twice during the fattening period. There were no significant differences in average daily gain, feed conversion and lean meat percentage between pigs treated with anthelmintic or placebo. This lack of effect may be explained in part by a rather low infection intensity, as measured by fecal egg counts, but in contrast, white spot numbers were moderate to high. A possible negative influence of other disease, mainly diarrhea due to Lawsonia intracellularis, on performance could not be excluded. Treatment with flubendazole twice during fattening prevented A. suum egg excretion but did not reduce the occurrence of liver white spots. To improve performance significantly, repeated treatments over several consecutive rounds might be necessary.

Objectives: Caras-Severin County presented the highest incidence of human trichinellosis (108.5 cases per 100,000 inhabitants) throughout Romania in 1993. This study aimed at providing an overview of the epidemiological and clinical characteristics of persons from this county hospitalized with nematodal infections between 1996 and 2008., Patients and Methods: Data were collected from the medical records of 269 patients admitted to two infectious diseases hospitals and found to have nematode helminthic infections., Results: Of the study group, 250 patients (92.9%) presented with trichinellosis, 10 (3.7%) with ascariasis, 7 (2.6%) with trichuriasis, and 2 (0.8%) with ascariasis and trichuriasis coinfections. Geohelminthic infections prevailed in children (68.4%). Giardiasis, a protozoan parasitic disease, was also found in 21 patients (7.8%)., Conclusions: Although trichinellosis cases decreased in this county, public health authorities must remain aware because new outbreaks may occur at any time as it happened in the neighboring counties. Regarding geohelminthiasis, parents must be aware of the potential risk of acquiring these infections and the major complications that may follow.

Although some studies have indicated that helminthic infections and house dust mite exposure may have an alleviating effect on wheeze, an interaction effect of both risk factors has not been examined in Thailand. The objective of this study was to investigate whether exposure to helminthic infections together with house dust mite allergen was associated with wheeze in children aged 18-36 months, living in an area of southem Thailand where helminthic infections are endemic. This study was undertaken as a part of The Prospective Cohort Study of Thai Children which recruited 1,076 children born between December 2000 and November 2001. A home dust sample was collected once when the infants were 12-18 months old to measure house dust mite allergen (Der p1). Questionnaire data on wheeze and a stool specimen for soil-transmitted helminth analysis were collected at age 18-36 months. Prevalence of exposure to house dust mite allergen (Der p1) > 10 microg/g dust was 31.8%. Soil-transmitted helminths were present in 25.0%, predominately Ascaris lumbricoides. Hookworm infection was associated with a physician's diagnosis of wheeze (OR 4.20, 95% CI 1.45-12.10) and hospitalized wheeze (OR 5.40, 95% Cl 1.26-23.01). Hospitalized wheeze was significantly higher in subjects exposed to Der p1 2-10 microg/g dust. Helminthic infections were not associated with a significant interaction effect with mite allergen against a risk of wheeze. Our survey confirms that hookworm infection and mite allergen exposure are independent risk factors for childhood wheeze and there is no evidence of important interaction between the two.

Ascaris lumbricoides infestations are endemic in tropical countries. Ascaris lumbricoides can occasionally cause biliary obstruction and result in obstructive jaundice or pancreatitis. We present a 34-year-old Bangladeshi woman with biliary ascariasis, resulting in recurrent pancreatitis. Her diagnosis was made with endoscopic retrograde cholangiopancreatography performed during an acute attack of pain.

We report serial MR findings in four patients with myelitis caused by visceral larva migrans syndrome due to Toxocara canis or Ascaris suum infection. MR imaging revealed spinal cord swelling with or without gadolinium enhancement in three patients. T2-weighted images showed high signal intensities preferentially located in both lateral and posterior columns. Antihelmintic and corticosteroid treatment yielded improvement in neurologic deficits and spinal lesions. However, one patient with T. canis infection relapsed associated with reappearance of MRI abnormalities.

In this report, a case of spontaneous missed abortion caused by Ascaris lumbricoides is presented and data from the literature are reviewed, A 26-year-old pregnant woman was presented with abnormal genital bleeding, abdominal pain.

Background: The effect of helminth infestation on the nutrition, growth, and physiology of the host is still poorly understood. Anthelmintic treatment of children in developing countries has had varying success in terms of growth improvements., Objective: The objective of this study was to assess the effect of regular deworming on child growth, physiology, and biochemical status., Design: The study was a 12-mo longitudinal intervention in 123 Bangladeshi children aged 2-5 y. Treatment (mebendazole) or placebo tablets were administered every 2 mo for 8 mo and again at 12 mo. Weight, height, midupper arm circumference, intestinal permeability, plasma albumin, alpha(1)-antichymotrypsin, and total protein concentration were assessed every 2 mo., Results: Treatment with mebendazole reduced the prevalence of Ascaris lumbricoides from 78% to 8%, of Trichuris trichiura from 65% to 9%, and of hookworm from 4% to 0%. There was no significant difference in the growth of treated children compared with those given placebo tablets. No changes in intestinal permeability or plasma albumin were observed after deworming. Significant decreases in total protein (P<0.001) and alpha(1)-antichymotrypsin (P<0.001) were observed in the treatment group, indicating possible reductions in inflammation and immunoglobulin concentration after deworming. A significant increase in the prevalence of Giardia intestinalis (from 4% to 49%) in the treatment group was associated with a short-term reduction in weight (P = 0.02) and higher intestinal permeability (P <0.001) in infected subjects. No long-term effects of G. intestinalis on growth were observed., Conclusion: Low-intensity helminth infections, predominantly of A. lumbricoides and T. trichiura, do not contribute significantly to the poor growth and biochemical status of rural Bangladeshi children.

This study was conducted in a rural agricultural area in Siniloan, Republic of the Philippines. The subjects were the school children. The nutritional status of 58 children infected with helminthiasis (Ascaris lumbricoides and Trichuris trichiura) was compared with that of 19 uninfected controls. Prevalence of Ascaris and Trichuris was 40.3% and 71.4% respectively, and 36.4% of infected children had both Ascaris and Trichuris infections. Statistically significant evidence of an adverse effect of helminthiasis on serum albumin levels was found, but no child had inadequate levels of other nutrients. Although helminthic infections increase the level of immunoglobulin E (IgE) in children endemically exposed to these parasites, there was no significant difference in the serum IgE among Ascaris or Trichuris infected groups in this study.

The prevalence, symptomatology, and outcome of Ascaris-induced liver abscess was studied prospectively in Kashmir, India, which is an endemic area of ascariasis, from December 1987 to December 1997. Of 510 patients with liver abscess admitted during this period, 74 had biliary ascariasis as the cause (14.51%). Of these 74 patients, 11 had intact ascaridae (live or dead) within the abscess. Six patients had a single abscess, and five had multiple abscesses. Seven patients had associated worms in the bile ducts. Ultrasonography was the main diagnostic procedure used. Ten patients were diagnosed based on clinical and ultrasound findings, and one was diagnosed during laparotomy. Most of the patients were young (age range 3-40 years) with a mean age of 17.20 years. Seven were females, and four were males. Ten patients underwent surgery; nine recovered completely, and one died postoperatively due to septicemia. Another patient died as well: a young child who presented late, was in refractory septic shock following suppurative cholangitis and liver abscess, and could not be taken for surgery. The mortality thus was 9.9%. Liver abscess following invasion of intrahepatic biliary radicles by ascaridae through the ampulla is an unusual complication of an otherwise common disease in Kashmir Valley, affecting children and young adults. The outcome depends on early diagnosis and surgical drainage of the abscess with extraction of worms from the ducts.

Parasitic diseases of the biliary tract occur frequently in tropical and subtropical areas and cause high morbidity and mortality. In general, neither the clinical presentation nor the general laboratory findings are sufficiently unique to raise the possibility of a parasitic biliary infestation in the mind of the surgeon. Once considered, however, the presence of a parasitic biliary infestation is easily confirmed. Most commonly this is accomplished by the identification of the parasite in stools or duodenal contents. Ultrasonography, CT and MRI are not only important in the diagnosis of parasitic biliary diseases but also in the follow-up and surveillance. ERCP is an excellent diagnostic tool for demonstrating the presence of parasites in the biliary tree. Furthermore, ERCP is also used in the therapy of biliary parasitic infestations and carries less morbidity and mortality than the surgical approach. Surgery is only indicated in complicated cases. Mechanisms that may be effective against parasites include: antibodies; cytotoxic T cells; T-cell-induced activated macrophages; natural killer cells, and a variety of cells that mediate antibody-dependent cell-mediated cytotoxicity and modulators of the immune system such as cytokines. Future research has to focus on the importance of these mechanisms for the immune evasion by parasites.

Efficacy trials of antihelminthic therapies conducted in Africa have reported improvements in children's growth, but nutritional evaluations of large-scale deworming programs are lacking. We evaluated the first-year effect on growth of a school-based deworming program in Zanzibar, where growth retardation occurs in school children. Children in four primary schools were given thrice-yearly mebendazole (500 mg) and compared with children in four schools that received twice-yearly mebendazole and children in four non-program schools. Evaluation schools were randomly selected and allocated to control, twice-yearly or thrice-yearly deworming. Approximately 1000 children in each program group completed the 1-y follow-up. Children <10 y old gained 0.27 kg more weight (P < 0.05) and 0.13 cm more height (P = 0.20) in the twice-yearly group, and 0. 20 kg more weight (P = 0.07) and 0.30 cm more height (P < 0.01) in the thrice-yearly group, compared with the control group. Children <10 y old with higher heights-for-age at baseline had higher weight and height gains in response to deworming. In children >/=10 y old, overall program effects on height or weight gains were not significant. But in this age range, younger boys had significant improvements in height gain with thrice-yearly deworming, and children with higher heights-for-age had greater improvements in weight gain with deworming. We conclude that the deworming program improved the growth of school children, especially children who were younger and less stunted, but the improvements were small. More effective antihelminthic regimens or additional dietary or disease control interventions may be needed to substantially improve the growth of school children in areas such as Zanzibar.

Stool examination, height and weight measurements were undertaken on 249 early primary school children at two schools in North-eastern Peninsular Malaysia. Helminth infected children were treated and follow-up anthropometric measurements and stool examination undertaken on all (n = 100) children at one of the schools 16 months later; to observe the relationship between acquisition of infection and growth. Baseline Ascaris prevalence rates at the two schools were 16.0% (23/144) and 47.6% (50/105) respectively whilst Trichuris rates were 33.3% (48/144) and 52.4% (55/105). Hookworm infection was uncommon. There was no difference in weight or height for age between infected and uninfected children at any time. Acquisition of worm infection over the initial 16 month follow-up period was not associated with significant decreases in growth rates. However the small subsets of children with heavy Ascaris infection were consistently lighter and shorter at all evaluation times. They also gained significantly less weight and tended to have reduced linear growth rates between measurements. Further interventional studies are required to determine if this association is one of cause and effect or largely incidental.

Experiments were conducted to study the possible influence of fasting on Ascaris suum and Oesophagostomum spp. In growing pigs. Forty young crossbred pigs naturally infected with A. suum and Oesophagostomum spp. were used. In one experiment 10 pigs were fasted and offered water ad libitum for 6 days, in another experiment for 10 days. Subsequently, these pigs, together with 10 non-fasted control pigs per experiment were slaughtered, and worm numbers, worm location, sex, developmental stage and female worm fecundity were determined. Pigs fasted for 10 but not for 6 days had decreased numbers of A. suum and Oesophagostomum spp. at slaughter vs controls, and worms were found in more distal locations in the gastrointestinal tract. Fasting for both 6 and 10 days significantly lowered the fecundity of both worm species.

This study examined the relationship between intestinal helminthiases and growth in urban slum schoolchildren. Children (n = 330) who received single doses of either pyrantel, albendazole, or placebo at baseline and again at 6 months were followed and examined fully at 0, 3, 6, and 12 months for helminth infections and anthropometry. Results of treatments indicated that all groups reduced their prevalence and intensity toward the period of the study. Reductions in intensity of both infections in the treatment groups were observed large in 3 and 12 months, whereas at 6 months reached mostly the initial level of infection. There was no significant difference in growth changes between the dewormed (once and twice) and the placebo groups. However, after controlling for some potential confounding factors, there was a significant relationship between reduction of A. lumbricoides infection and height gain at 3 and 12 months (both P < 0.05). In addition, there was a significant association between reduction in T. trichiura infection and increased midarm circumference at 3 and 12 months (P < 0.002 and P < 0.08, respectively). We conclude that treatment of helminth infections in school-age children may improve growth in areas where malnutrition and helminth infections are prevalent.

Light or moderate intensity infection with Schistosoma mansoni may contribute to growth deficits. We report on the effects of treatment for S. mansoni on growth and development in Brazilian schoolchildren. Anthropometric measurements were taken from 539 S. mansoni-infected children and their age- and sex-matched egg-negative controls between the ages of 7 and 15 years. The children as a whole exhibited chronic malnutrition, with growth retardation in height evident in 21% of the population. Infected children, however, were significantly smaller in height, weight, mid upper arm circumference (UAC), tricep skinfold (TSF), and subscapular skinfold (SSF) measurements than control children (P < 0.05). These differences were due primarily to a greater disparity between infected and egg-negative girls in height (P < 0.01), weight (P = 0.01), UAC (P = 0.O2), and TSF (P < 0.01). Nevertheless, girls demonstrated a better level of development and nutrition compared with boys. While infected boys were shorter and weighed less than controls, these differences were not significant. Growth and development in girls was negatively correlated with intensity of infection. Coinfection with S. mansoni and Trichuris appeared to act synergistically in the development of malnutrition.

Two groups of 20 pigs weighing approx. 26 kg were offered either ground barley plus protein supplement (GBP) or commercial pelleted feed (CPF), two diets consisting of nearly the same amounts of carbohydrates, proteins and micronutrients. All pigs were experimentally infected with 600 infective Ascaris suum eggs and 6000 infective Oesophagostomum spp. larvae and followed coprologically for approx. 12 weeks post infection, whereafter they were slaughtered. The number of Oesophagostomum spp. and A. suum eggs was significantly higher in the GBP-fed pigs compared with the CPF-fed pigs (P < 0.0001). The mean worm burden of adult Oesophagostomum spp. was higher in the GBP-pigs than in the CPF-pigs (P < 0.05), while the mean worm burden of adult A. suum in the two groups was not significantly different. The results indicate that two diets, both fulfilling the requirements of modern pig raising, may result in different establishment rates of natural adult gastrointestinal helminths in swine.

Ascaris lumbroicoides is the most prevalent human parasite worldwide. Although usually asymptomatic, ascaris is responsible for a variety of severe complications such as intestinal obstruction, cholangitis, or hepatitis, which are caused by worm migration. This article is the second known case report of pancreatitis caused by biliary ascaris during pregnancy. We also review the pathophysiology of this disease and review the various treatment modalities available for pregnant patients. We believe that because of the growing influx of immigrants from endemic areas into the United States, the clinician needs a basic understanding of the etiology, diagnosis, and treatment of biliary ascarasis.

An 18-month study was conducted from February 1989 to August 1990 to examine the effect of regular deworming on child growth and nutritional status. A sample of 1402 children, from 2 to 6 years old, were divided into a treatment group and a control group. The 688 children in the treatment group received a 500 mg single dose of mebendazole, while the 714 children in the control group were given a placebo. Height, weight and mid-upper arm circumference (MUAC) were measured on monthly household visits. Growth was measured in terms of the change in height-for-age, weight-for-age, weight-for-height and MUAC over 18 months. The initial prevalence of infection was estimated from a random sample of 96 children (49 treated, 47 control). The initial overall prevalence of Ascaris lumbricoides, Trichuris trichiura and hookworm was 71, 44 and 10% respectively. The final prevalence of infection, estimated from a random sample of 265 children, was A. lumbricoides 6%, T. trichiura 6% and hookworm 2% in the mebendazole group compared with 64, 18 and 19% respectively in the placebo group. Despite the successful treatment of helminths, there was no significant improvement in the growth of treated children compared with their untreated counterparts in terms of the change in z-scores of height-for-age, weight-for-age, weight-for-height and MUAC. The factors which may have contributed to this outcome are discussed.

We studied physical fitness with the Harvard Step Test, growth, and appetite in primary school boys infected with hookworm (96% baseline prevalence), Trichuris trichiura (98% prevalence) and Ascaris lumbricoides (41% prevalence) who received a single 600-mg dose of albendazole or an identical placebo. Boys were examined, allocated at random within pairs by descending hookworm egg count to placebo (n = 26) or albendazole (n = 27) groups, treated, and re-examined 4 mo later. Four months after treatment, the albendazole group showed highly significant improvements in fitness score, resting heart rate, and heart rates at 1, 2, 3 and 4 min after the Harvard Step Test, whereas the placebo group had not changed significantly. The albendazole group also exhibited significantly more rapid growth judged by weight gain (1.0 kg greater than the placebo group, P < 0.0002), height increment (0.6 cm more, P < 0.003), arm circumference (0.3 cm more, P < 0.0002), and triceps and subscapular skinfolds (1.0 mm more, P < 0.0002), and showed improved appetite with objective and subjective measures. We conclude that single-dose treatment with albendazole can allow improved physical fitness, growth, and appetite in school-age children in areas where these helminths and poor growth are highly prevalent.

The present review will examine epidemiological perspectives and be confined mainly to the results of those field studies published since 1975 in order to provide concrete scientific evidence of the effect of ascariasis on childhood malnutrition, particularly on growth. The field studies were done in many developing countries from Africa, Asia and Latin America, using cross-sectional and intervention studies in which anthelmintics were employed, with different dosing frequency and follow-up periods ranging from 33 days to 2 years. In general, a better nutritional status in terms of growth, lactose tolerance, vitamins A and C, and albumin levels were observed among Ascaris-free or treated than among Ascaris-infected or untreated children even in cross-sectional or non-randomized studies. More importantly, the improvement in weight or height after chemotherapeutic treatment was found to be significant particularly in those randomized controlled studies with an initially high prevalence of ascariasis and malnutrition, a low prevalence of other intestinal parasites, repetitive and regular treatments of children with tetramisole, levamisole or pyrantel, within a period of 12 or 24 months. Reasons for failures to detect improved growth in some studies are provided. This review strongly indicates that A. lumbricoides infection definitely retards childhood growth.

Amongst 876 cases suffering from ascariasis 662 cases were managed conservatively and 214 cases were treated by surgery. Surgical complications were found to be more common in males in the age group of 6-10 years. Principal clinical features included pain abdomen (99.54%), constipation (80.25%), vomiting (67.46%), abdominal distension (47.03%), palpable worm masses in abdomen (35.50%), visible peristalsis (27.63%), worms in vomitus (24.20%) and palpable worm clumps on rectal examination (20.09%). Principal clinical diagnosis were worm colics (48.74%), sub-acute intestinal obstruction (27.74%), acute intestinal obstruction (11.42%) and acute intestinal obstruction with strangulation (5.71%); rest of the cases included worm cholecystitis (2.63%), obstructive jaundice (1.71%), bile peritonitis (0.91%), intestinal perforation (0.68%) and acute appendicitis (0.46%). Surgical procedures performed were milking of worms (34.12%), resection anastomosis of small intestine (23.36%), enterotomy with removal of worms (16.36%), cholecystectomy with T-tube drainage (12.15%), cholecystectomy (8.41%), appendectomy (1.87%), resection anastomosis with excision of Meckel's diverticulum (1.40%), repair of intestinal perforation with peritoneal toilet (1.40%) and cholecystectomy with choledochoduodenostomy (0.93%). In surgically managed patients 35 cases died of septicaemia and in conservatively managed cases 3 died of encephalitis with an overall mortality of 4.34%.

The mechanism by which small animals such as rodents resist or eliminate nematode parasites requires mucosal inflammation as the final effector of the immune response. The resulting freedom from chronic infection may be worth the price of short-term illness. Putative vaccines which attempt to enhance the natural effect will have to take into account the inflammatory cost to the host. Human helminthiases involve a more stable equilibrium between host and parasite. The medical literature on hookworm disease and clinical ascariasis describes, for the former, some chronic inflammatory effects correlated with worm burden, but for the latter a less quantified or predictable set of detrimental effects. We describe a current, systematic study of the inflammatory response to whipworm infection, in which anaemia, growth retardation and intestinal leakiness are viewed as predictable consequences related to infection intensity. There is evidence for the absence of cell-mediated immunopathology. However, a specific, IgE-mediated local anaphylaxis may, at least partly, mediate the deleterious effects. Increased numbers of mucosal macrophages may also contribute to the chronic, systemic effects through their output of cytokines. Similar attempts to show the mechanisms of pathogenesis and quantify the effects of hookworm disease should be undertaken.

Small intestinal histopathology and absorption were examined in Beagle puppies infected with either a moderate or a low burden of Toxocara canis. Infection with T. canis significantly reduced absorption of xylose, but only slightly delayed absorption of para-aminobenzoic acid. Fat assimilation was reduced and faecal proteolytic activity was increased. A significant reduction in villous height occurred and was inversely related to the extent of the infection. Villous goblet cell numbers, particularly those in the luminal third of the villus, were lowest and crypt goblet cell numbers were highest in the most heavily infected of the puppies. Villous goblet cell numbers increased rapidly after treatment of the puppies with piperazine or after the spontaneous elimination of the T. canis infection while crypt goblet cell numbers were less affected by elimination of the parasites. Intra-epithelial lymphocyte numbers were lowest in 33- to 37-day-old puppies infected with greater than 127 T. canis and highest in 44- to 46-day-old puppies losing their infection. Infection with T. canis had no apparent effect on mast cell numbers or pyroninophilic cell numbers in the lamina propria.

One hundred children aged 24-72 months who had history of passing roundworms during the preceding 12 months were compared with 100 children without such history. The two groups were matched for age, sex, economic status, and birth order. Children who had ascaris were 2.1 cm shorter in height, 0.6 cm, thinner for mid-arm circumference, and 0.38 kg lighter in weight compared to the children who did not pass ascaris. The first two of these differences were statistically significant (P less than 0.005). It is concluded that: 1. ascariasis contributes significantly to malnutrition in communities where both coexist; 2. periodic deworming should form part of community nutrition programmes in areas where ascariasis is common; 3. future studies of a similar nature should include recording of height, arm circumference, and birth order.

Growth rates, measures of ascarid burden, and the levels of anteroventral pneumonia and atrophic rhinitis at slaughter were determined for 352 hogs born between March 8 and March 28, 1987 on 15 farms located in Prince Edward Island. Regression analyses were used to determine associations between average daily gain (ADG) and independent variables controlling for sex, farm, and litters nested within farm. The regression model accounted for 75.4% of the variation in ADG. The number of intestinal ascarids at slaughter did not affect ADG. However, the "life-time burden" (a composite measure based on fecal egg counts and duration of infection) was associated with ADG (p less than 0.05) in a quadratic manner. Although heavy ascarid burdens decreased the growth rate of swine, the magnitude of the effect was minimal. The maximum improvement one could expect from reducing the ascarid burden on heavily infected farms would be less than 1%. Severe atrophic rhinitis and the presence of anteroventral pneumonia each had a detrimental effect on ADG (p less than 0.001). The corresponding reductions in mean ADG were 7.7% and 2.8% respectively. There was significant interaction between the effects of atrophic rhinitis and anteroventral pneumonia on ADG (p less than 0.05). Hogs with both anteroventral pneumonia and severe atrophic rhinitis had a 17.6% lower ADG than hogs with neither disease. There is much greater potential for improvement in ADG through control of respiratory diseases than through control of ascariasis.

We studied physical fitness with the Harvard step test (HST), in primary schoolboys infected with hookworm (91% baseline prevalence), Trichuris trichiura (94%) and Ascaris lumbricoides (39-40%) who received a single 400 mg dose of albendazole or an identical placebo. Boys were examined, allocated at random to placebo or albendazole groups, treated, and re-examined 7 weeks later. The 2 groups did not differ significantly before treatment in age, anthropometry, haemoglobin levels, prevalence or intensity of the 3 helminth infections, or in initial HST fitness scores and heart rates. Seven weeks after treatment, the albendazole group (n = 18) exhibited significant improvements in fitness scores and heart rates at 1, 2, 3, and 4 min after the HST while in the placebo group (n = 15) these quantities had not changed significantly. After treatment, the albendazole group had significant decreases in the logarithmic egg counts for hookworm (80% reduction in arithmetic means) and A. lumbricoides (100% reduction); T. trichiura egg counts did not change significantly. The placebo group showed a borderline increase in the logarithms of hookworm egg counts and no significant change in T. trichiura and A. lumbricoides egg counts. Multiple regression analysis showed that the significant linear predictors of increase in HST score after treatment were decrease in resting heart rate after treatment, and decreases in hookworm egg counts and logarithms of A. lumbricoides egg counts after treatment. We conclude that single dose treatment with albendazole, despite continual exposure to reinfection, can allow improved physical fitness in schoolboys in areas where soil-transmitted helminths and protein-energy malnutrition are highly prevalent.

The mechanisms involved in the pathophysiological disturbances associated with the presence of mature Parascaris equorum in the small intestine were investigated with radioisotopic techniques. The results suggested that, compared with worm-free controls, infected foals had a reduction in gut motility, an increase in the body solids ratio, a lowering of the body pool of albumin and a decreased ability to incorporate dietary methionine into plasma protein.

Ninety-eight crossbred growing-finishing swine were used in 2 experiments to investigate the interaction between naturally occurring Ascaris suum infections and excess copper ingestion. In both experiments, pigs were fed a 14% crude protein basal diet or the basal diet + 250 ppm copper. These 2 dietary groups were subsequently divided into 2 additional treatment groups (A. suum-infected or uninfected) based on worm recovery from the intestine or from fecal egg counts. Excess dietary copper improved pig performance slightly, but it dramatically increased liver, kidney and lung copper levels. The A. suum infection did not affect pig performance, but it tended (not significantly) to reduce tissue copper levels. Serum copper was not affected by dietary copper or by A. suum infection.