title: Detection of Leishmania donovani in peripheral blood of asymptomatic individuals in contact with patients with visceral leishmaniasis.
abstract: The majority of individuals infected with Leishmania donovani complex remain asymptomatic. They may act as transmission reservoirs for visceral leishmaniasis (VL). We investigated sero-prevalence of L. donovani complex amongst those closely associated with patients with VL and whether these sero-reactive individuals had Leishmania parasites in their peripheral blood. Other risk factors were also investigated.
  
  
  
  A total of 257 individuals in contact with patients with VL were tested for anti-Leishmania antibodies by rK39 immunochromatographic test (rK39 ICT), ELISA using promastigote antigen (p-ELISA) and indirect fluorescent antibody test (IFAT). Buffy coats of rK39 ICT positive individuals were cultured; sero-reactive buffy coats were tested for Leishmania DNA by ITS1 PCR. DNA obtained from culture was sequenced to confirm Leishmania species. Risk factors were evaluated for each sero-positive sample.
  
  
  
  The results showed 29.2% (75/257) prevalence by serological tests: 14.4% (37/257) were positive by rK39 ICT, 25.3% (65/257) by p-ELISA, 18.3% (47/257) by IFAT and 10.9% (28/257) by all three serological methods. Ten percent (3/30) of cultures were positive for Leishmania promastigotes. Only 3% (2/74) sero-reactive buffy coats were positive for DNA; sequence analysis revealed L. donovani species. Significant risk factors were age, working as farmers, domestic animals in household and proximity to animal shelters.
  
  
  
  Asymptomatic family members of patients with VL can carry live L. donovani in peripheral blood and may act as potential reservoirs.
  
  
  
  BankIt1863680 Leishmania KT921417 (DNA sequences of the ribosomal ITS1 region of L. donovani).
authors.affiliation: Parasitology Department, Centre for Infectious Diseases and Microbiology Laboratory Services (CIDMLS), ICPMR, Westmead Hospital, NSW, Australia Molecular Mycology Research Laboratory, Centre for Infectious Diseases and Microbiology, Marie Bashir Institute, Westmead Institute for Medical Research, NSW, Australia Discipline of Medicine, Sydney Medical School, University of Sydney, NSW, Australia Communicable Disease Control Unit, Directorate General of Health Services, Mohakhali, Dhaka, Bangladesh. sban7118@uni.sydney.edu.au.
authors.forename: Sultana S
authors.initials: SS
authors.lastname: Banu
authors.affiliation: Molecular Mycology Research Laboratory, Centre for Infectious Diseases and Microbiology, Marie Bashir Institute, Westmead Institute for Medical Research, NSW, Australia Discipline of Medicine, Sydney Medical School, University of Sydney, NSW, Australia.
authors.forename: Wieland
authors.initials: W
authors.lastname: Meyer
authors.affiliation: Communicable Disease Control Unit, Directorate General of Health Services, Mohakhali, Dhaka, Bangladesh.
authors.forename: Be-Nazir
authors.initials: BN
authors.lastname: Ahmed
authors.affiliation: Parasitology Department, Centre for Infectious Diseases and Microbiology Laboratory Services (CIDMLS), ICPMR, Westmead Hospital, NSW, Australia.
authors.forename: Rady
authors.initials: R
authors.lastname: Kim
authors.affiliation: Parasitology Department, Centre for Infectious Diseases and Microbiology Laboratory Services (CIDMLS), ICPMR, Westmead Hospital, NSW, Australia Discipline of Medicine, Sydney Medical School, University of Sydney, NSW, Australia.
authors.forename: Rogan
authors.initials: R
authors.lastname: Lee
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D000829:Animals, Domestic; D000913:Antibodies, Protozoan / Q000097:blood*; D000953:Antigens, Protozoan / Q000276:immunology*; D001459:Bangladesh / Q000453:epidemiology; D002353:Carrier State / Q000453:epidemiology*; D002648:Child; D002675:Child, Preschool; D016054:DNA, Protozoan / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D007893:Leishmania donovani / Q000235:genetics / Q000254:growth & development; D007898:Leishmaniasis, Visceral / Q000469:parasitology* / Q000635:transmission; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D015995:Prevalence; D012307:Risk Factors; D016036:Seroepidemiologic Studies; D055815:Young Adult
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D016054:DNA, Protozoan
keywords: Asymptomatic infection; Bangladesh; Culture; Leishmania; PCR; Serology