No abstract

SummaryThe commercially available ICT Card Test for bancroftian filariasis was evaluated for its sensitivity and specificity in detecting microfilaria carriers among 189 individuals each in filariasis-endemic and nonendemic areas in South India, and compared to both conventional night blood finger prick thick blood smear examination and venous blood membrane filtration. Though the specificity of the test was 100% in comparison to both, the sensitivity was 98.5% against the finger prick thick blood smear and 71.9 compared to the membrane filtration technique. Similarly, the positive predictive value was 100% against both techniques, but the negative predictive values were 99.5% against the finger prick thick blood smear and 88.3% compared to the membrane filtration technique. The test's lower sensitivity compared to the filtration technique requires further investigation.keywords ICT card test, Wuchereria bancrofti, immunodiagnosis, filariasis correspondence Dr S.P. Pani, Vector

Outbreaks of acute encephalitis syndrome (AES) with high fatality and disability, are reported every year in the Gorakhpur region of Uttar Pradesh, India, with the etiology of >60% of the cases being attributed to scrub typhus. In the present study, the prevalence of Orientia tsutsugamushi, the etiological agent of scrub typhus, was investigated among animal hosts and their ectoparasitic trombiculid mites prevalent in AES-reported areas of Gorakhpur. A total of 154 rodents/shrews were collected using 777 Sherman traps set in 12 study villages, and the overall trap rate was 19.8%. In total, 2726 trombiculid mites belonging to 12 species were collected from 154 rodents/shrews trapped. The shrew mouse Suncus murinus was the predominant animal species (78.6%) collected. The principal vector mite Leptotrombidium deliense was the predominant species (82.7%), and its index was 14.6 per animal. Of 114 rodent/shrew sera samples screened through the Weil-Felix test, 57% were positive for antibodies against O. tsutsugamushi. Of 128 blood samples tested by polymerase chain reaction (PCR), one rodent sample was positive for the gene encoding 56 kDa protein and 25 for 60 kDa. Among 2726 mite samples tested as 315 pools through nested PCR, seven pools were positive for 56 kDa gene. Phylogenetic analysis confirmed circulation of Gilliam, Karp, and TA678 serotypes of O. tsutsugamushi in Gorakhpur. The study clearly demonstrated natural infection of O. tsutsugamushi in both small-animal hosts and vector mites in the AES-reporting villages of Gorakhpur, which confirms transmission of the scrub typhus pathogen in this region. The high infestation rate of L. deliense with O. tsutsugamushi infection indicates that the people living in the rural villages of Gorakhpur are at risk of infection with scrub typhus, which might lead to AES.