Cross-reaction of antigen preparations from adult and larval stages of the parasite Setaria equina with sera from infected humans with Wuchereria bancrofti

Crude antigenic preparations from Setaria equina were used in ELISA and Western blotting to examine cross-reaction with human sera from areas endemic for bancroftian filariasis. Sera from normal subjects from non-endemic areas were included as negative controls. Cross-reaction was found between 5. equina antigens and antibodies in the sera of Wuchereria bancrofti-infected patients, with the highest levels observed between sera of chronic infected patients and Setaria spp. crude female worm surface antigen [CFSWA]. In the absence of active transmission of Setaria spp. infection, CFWSA is useful to detect chronic W. bancrofti infection before patients become symptomatic, particularly when chronic patients are known to be amicrofilaraemic. In the presence of active 5. equina infection, antigens from the adult and microfilaraemic stages showed the highest degree of cross-reaction with human sera

longitudinal study of Schistosome intermediate host snail populations and their trematode infection in certain areas of Egypt

The seasonal variation of Biomphalaria alexandrina and Bulinus truncatus populations and their infection rates with schistosome and other trematode cercariae were studied longitudinally in four water courses located in Giza and Fayoum governorates. The abundance of both species varied from year to year and according to the type of habitat. The mean prevalence of Schistosoma mansoni in Biomphalaria was 0.29% and that of S. Haematobium in Bulinus was 1.36%. The seasonal variations of age structure of the two vector snails were monitored throughout the survey period. Infection rates with schistosome and other trematodes among Bulinus and Biomphalaria increased with the increase in snail size. Data suggested the occurrence of an antagonistic interaction between schistosome and non- human cercariae, especially echinostome in infected snails

Antibodies against rickettsia in humans and potential vector ticks from dhofar, Oman

Objective - To determine the extent of rickettsial infections prevalence of potential vector ticks in the rural population of Dhofar, Oman. Method - Human sera [n = 347] were obtained from six rural localities [school children, farmers, outpatients] in Dhofar, Sultanate of Oman. Sera were tested by immunofluorescence for the presence of antibodies reacting with Rickettsia conorii antigen. Results - More than half the samples [59%] gave positive reactions [titres of at least 1:64]. Ticks [n=707] were collected from cattle, camels and goats [n=102] and included Amblyomma variegatum, Hyalomma a. anatolicum, H. dromedarii, H. rufipes and Rhipicephalus spp., all of which can potentially transmit rickettsiae to humans. Conclusion - The results suggest that rickettsial infections are common among the rural population of Dhofar