Seroepidemiological Survey of Visceral Leishmaniasis by Direct Agglutination Test in Bojnoord District, North Khorasan Province in 2007

This study aimed to determine of the seroprevalence of visceral leishmaniasis to design a prevention and control program in Bojnoord district. This was a descriptive and cross sectional study with multistage random sampling method. The study was carried out on children up to 12 years old and 10% of adult’s population in 8 rural areas of Bojnoord district in 2007. In total, 1608 blood samples were collected to detect anti-Leishmania antibodies. All the samples were tested by direct agglutination test (DAT). In order to determine Leishmania species, necropsy was performed on four suspected dogs in the studied areas. The species of Leishmania was determined by RAPD-PCR and PCR-RFLP methods using to amplify the ribosomal internal transcribed spacer 1 (ITS1). Thirty and eight (2.36%) out of 1608 collected blood samples had anti-Leishmania antibodies at titer 1:800 and nine (0.56%) were just positive at 1:3200 by DAT. There was no statistically significant difference between female and male seroprevalence (p<0/05). The seoprevalence in children <=12 years old compared to individuals greater than 12 years old did not show any statistically significant (p<0/05). Amastigotes were observed in all 4 necropsied dogs. The species of Leishmania isolated from 2 dogs, was determined as L.Infantum. Their ITS1 sequences were registered with Accession numbers EU810776 and EU810777 in NCBI. These findings showed that visceral leishmaniasis has been circulated with low endemicity in Bojnoord district. Therefore an appropriate monitoring system is needed for health services in this area.