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In 2007, the rate of intestinal helminth infection in primary school-aged children in a rural village in Southwestern Kenya was estimated to be at least 68%, based on direct stool smear. Since the 2007 survey, these same school children have been treated with 400-mg albendazole every 3 months. We repeated a cross-sectional stool survey in the same area in 2010 (i.e. 3 years later) to estimate the current parasite prevalence. While only 44.5% of children were infected in 2010, the decline was not as marked as one might expect from a well-managed quarterly deworming campaign. Due to the relative insensitivity of the technique utilized here-the direct smear examination of a single stool sample-we were only able to identify heavy infections, and the true rate of parasitism is likely much higher, suggesting heavy environmental contamination and rapid re-infection rates. Community education and sanitation improvements are needed for more definitive impact.

Relative eosinophilia (defined as an eosinophil percentage >5% but an eosinophil count <450 cells/microL) is significantly associated with helminth infection in recently arrived West African immigrants (odds ratio, 20.5; 95% confidence interval, 2.7-154). The main parasitic causes related to relative eosinophilia are geohelminthic diseases (specifically, hookworms) and schistosomiasis.

A pair of Mammomonogamus laryngeus roundworms in copula was recovered from the duodenum of a 72-year-old male Thai patient from Kanchanaburi Province. Eggs were also found in the stool of the patient. This is the first case of Mammomonogamus infection originating in Thailand, as the previous two reports from Thailand attributed the infection as originating in Malaysia. The occurrence of adult worms in the duodenum is unusual and differs from previous findings in the larynx, posterior pharynx, tracheal wall and bronchi. This adds a new dimension to the manifestation of the infection.

The present study was the first to investigate the potential of saliva in community diagnosis of the major human intestinal nematode infections, Trichuris trichiura, Ascaris lumbricoides, and the hookworms. Immunoglobulin G (IgG) antibodies specific to parasite antigens were quantified in saliva samples of 187 individuals (all ages) from a St Lucian community, and 120 school-aged children from Tanga region, Tanzania, and relationships with current infection status (determined by numbers of parasite eggs in stool) were examined. For T. trichiura infection, the age relationships of parasite-specific salivary IgG antibodies mirrored those of infection intensity at the community level. Within both areas, children with current T. trichiura infection exhibited significantly higher anti-T. trichiura salivary IgG responses than uninfected children. Similar trends were apparent for A. lumbricoides and hookworm infections, though not to a level of statistical significance. Comparison of mean T. trichiura infection levels and antibody responses in age-matched children from St Lucia and Tanzania suggested that measurement of parasite-specific salivary IgG may have potential as a marker of transmission intensity at the community level.

Two cases of children with abdominal angiostrongyliasis acquired within the United States are reported. The index patient presented with complaints consistent with appendicitis, but at surgery findings were thought to represent an atypical presentation of a Meckel's diverticulum. His sole sibling (sister) had eosinophilia, no other intestinal parasites on fecal examination, and a positive serologic test, all suggesting infection with Angiostrongylus costaricensis. Because infections with this parasite are not known to result from human-to-human transmission, his sister's infection represents a second case.

A serodiagnostic assay system to detect human anisakiasis is described. This assay uses a microenzyme-linked immunosorbent assay with monoclonal antibody An2 that recognizes the antigen specifically found in Anisakis simplex larvae. The data showed that sera from infected patients reacted strongly with the A. simplex larvae antigen that was immobilized with monoclonal antibody An2 on microplates. Patients' IgG, IgA, IgM, and IgE reacted strongly with An2-defined antigen at 4 or 5 weeks and at 1 or 7 days, respectively, after the onset of clinical symptoms of anisakiasis. However, sera from healthy persons did not react, even though they often ate raw fish. This indicates a high diagnostic specificity of this assay system for clinically manifested anisakiasis.

The diagnosis of the fourth reported case of intestinal anisakiasis in the United States was based on the morphologic characteristics of the worm in histologic sections of resected ileum. Detection of antibodies to the worm by a radioallergosorbent test (RAST), enzyme-linked immunosorbent assay (ELISA), and an immunofluorescent antibody assay (IFA) support the diagnosis. IgE antibodies in patient serum reacted specifically to larval Anisakis antigens but not to larval Ascaris antigens in the RAST. IgG and IgM antibodies to larval Anisakis antigen could be detected by ELISA up to six months after infection. IFA findings demonstrated that patient serum recognized the excretory-secretory products produced by the worm and showed their presence in vivo. These products appear to originate from the excretory pore and dorsal esophageal gland of the larval parasite.

Nematodes occupying the gastrointestinal (GI) tract of man shed an as yet undefined array of chemicals into their environment. To combat effectively the potentially debilitating disease caused by infection with these organisms we must (a) define the parasite products chemically, (b) determine their ability to induce protective immunity (or to counter a protective immune response), and (c) establish their potential for the diagnosis of infection. Whilst it has become clear that "antigens" can be derived from within the parasite and from the turnover of external cuticular components (the term "ES" must include both), further work is necessary to establish the significance of these molecules to the survival of the parasite. In this context, a number of questions will be answered in the near future. For example, how important is the hookworm protease to parasite nutrition? Can vaccination using the genetically engineered and purified enzyme generate protective immunity? Will the stichocyte secretions of Trichuris trichiura prove to be as immunogenic as those of Trichinella spiralis? (Surprisingly, little has been published with regard to the presence of enzymes in stichocyte secretions.) Are GI nematodes on the way out?

This is apparently the second report of a case of human meningoencephalitis caused by the nematode Micronema deletrix. The patient had severe granulomatous meningoencephalitis with numerous foci of hemorrhage and encephalomalacia. Numerous adult female and larval M. deletrix were in the brain. The organisms probably inhabit decaying organic material, but occasionally parasitize the kidney, nose, or central nervous system of the horse. In its parasitic form the nematode replicates parthenogenetically.

The enzyme-linked immunosorbent assay (ELISA) was employed for the sero-diagnosis of Angiostrongylus cantonensis infections in rats and man. Metabolic and 'purified' antigens of adult or juvenile A. cantonensis were evaluated by ELISA and compared against Toxocara canis antigen for sensitivity and specificity. Sera and cerebrospinal fluid (CSF) from both rats and man gave higher ELISA values against antigens of A. cantonensis than those obtained from negative control samples. The results showed that cross reaction occurred between T. canis and A. cantonensis. Of four A. cantonensis antigens tested, a Sephacryl S-300 'purified' fraction was shown to be superior in the ELISA to determine angiostrongyliasis.

The serum of patients with parasitologically confirmed and one patient with a clinically presumptive case of anisakiasis were tested by the radioallergosorbent test (RAST) and counter-electrophoresis (CEP) for IgE and IgG antibodies, respectively, using antigens prepared from larval (L3) stage Anisakis simplex and larval (L2) stage Toxocara canis. All sera were RAST-positive to the A. simplex antigen and RAST-negative to the T. canis antigen. All sera were CEP-negative to both antigens. The presence of a specific IgE antibody suggests that the RAST could serve as a useful technique for the serodiagnosis of anisakiasis in man.

Intestinal anisakiasis refers to the accidental infection of humans by a marine nematode as a result of eating raw fish which contains larval stages of the nematode sub-family Anisakinae. The symptoms mimic appendicitis or regional enteritis and most cases are diagnosed post-operatively. This patient developed acute intestinal symptoms two weeks after eating raw salmon. A degenerating 150 micron larva accompanied by acute inflammation and granulation tissue was found in an adhesive band which extended from her jejunum to her omentum. Examination of a single salmon obtained from the same market where the patient shopped resulted in the recovery of 5 viable larvae, and confirmed the impression that anisakine infection of market fish is common. A related species (Phocanema) causes infestation, but not symptomatic disease. Although common in countries where raw fish is routinely eaten (e.g., Japan), its frequency is not proportional to the size of the group at risk, suggesting that predisposing factors influence the course of exposure. Preventative measures include freezing at -17 degrees for 24 hours.

The development of serum and cellular assays to measure responses to Angiostrongylus cantonensis antigen, purified by affinity chromatography, formed the basis of this study. The specificity and sensitivity of these techniques were established in immunized rabbits and in naturally and laboratory-infected rats. The assays were then used to determine levels of immunological responsiveness to A. cantonensis in four Australian populations. There was a direct correlation between the prevalence of the parasite in rodents and the proportion of human reactors to A. cantonensis antigen in each population studied. Five patients with similar clinical histories and presenting symptoms suggesting eosinophilic meningitis were investigated; three were admitted to hospital. Haematological examination demonstrated hypereosinophilia in all five while three had, in addition, a cerebrospinal fluid eosinophilia. Serological tests and assays of cell-mediated responses to A. cantonensis antigen showed elevated immunological reactivity during the acute phase of illness with a subsequent decrease in reactivity corresponding with the progressive recovery of the patient.

Unilateral iritis, keratitis and episcleritis presented in a 45-year-old female Melanesian from New Britain, Papua New Guinea. A motile nematode was seen in the anterior vitreous but was not recovered. Inflammation resolved with topical corticosteroid and antibiotic treatment, but visual impairment persisted. She failed to return for repeat serology after discharge, and measurement of serum antibody levels to Angiostrongylus cantonensis in the single specimen obtained, using the direct and indirect immunofluorescent tests, showed a titre of 1:128. Ocular angiostrongyliasis is briefly reviewed and the differential diagnosis of intra-ocular nematode infestation is presented.

As part of an investigation of intestinal parasitic infections of rural Kenyan people, a study was undertaken to examine variations in faecal egg counts and to assess the sensitivity of the ether sedimentation technique of faecal processing in the diagnosis of helminth infections. Three faecal samples a day were collected for five consecutive days from 10 men known to harbour a total of 23 nematode infections of Ascaris lumbricoides, Trichuris trichiura and hookworm. Considerable variation in egg counts was encountered among faecal samples collected from the same stool, as well as over the five day period. Some possible causes of this variation are discussed, especially in relation to a high fibre diet. The technique was found to be about 95% effective in detecting an infection.

The authors recently encountered a patient with omental anisakiasis who presented with features of acute appendicitis and who made an uneventful recovery following resection of an inflammatory omental mass containing the larva(e). Anisakiasis refers to infestation of humans by species of marine nematode larvae belonging to the subfamily Anisakinae. Although this condition is rarely reported in the United States, it has been well described both in Holland and in the Orient. Several publications in the Japanese literature have detailed the morphology of the parasite and the clinical symptoms of infestation. The source of infestation is most often raw or uncooked fish, the latter widely enjoyed as a foodstuff in the Orient, but less popular in the United States. With the growing popularity of "sushi" bars and the increasing numbers of Americans developing a taste for raw fish, this condition may become more prevalent in the future.