感染症と治療ジャーナル

抽象的な

Prevalence of Asymptomatic Visceral Leishmaniasis among under 5 Years Contacts of Confirmed Cases in Thiqar Governorate, 2012

Haidar A. Hantosh and Faris H. Al Lami

Introduction: Visceral leishmaniasis (VL) or Kala-Azar is a life-threatening parasitic infection. There is evidence that in endemic areas of VL only about 20% of the subjects infected by Leishmania will develop symptomatic VL. The majority of the infected individuals have a sub-clinical infection that may remain completely asymptomatic. In Iraq, no data about asymptomatic VL are available although they are valuable to complete the epidemiological picture of the disease and help evaluating current control measures.
Methods: Screening of children of close family contacts and neighborhood contacts of 50 confirmed VL cases was done to determine the prevalence of asymptomatic infection among the contacts. Five children aged less than five years were selected from the same house or the immediately close neighborhood, making a total of 250 children. rk39 was used as a screening test; those with positive result were confirmed by Indirect Immunoflurecent Test (IFAT). All confirmed cases were followed for the maximum incubation period (six months); if symptoms developed during this period, the case was considered as “latent VL”, otherwise it was considered as “asymptomatic VL”.
Results: The prevalence of asymptomatic infection was 34.4%. All those tested positive for rk39 were tested positive for IFAT. The prevalence was significantly higher in household than neighborhood contacts, and in those living in mud-made houses than those living in block-made or mixed houses (p<0.05). None of seropositive contacts progressed into latent symptomatic case.
Conclusion: It was concluded that asymptomatic VL infections are frequent in Thiqar province and those living in the same case house and mud-made houses are at higher risk to contract infection.