Survey of domestic cattle for anti-Leishmania antibodies and Leishmania DNA in a visceral leishmaniasis endemic area of Bangladesh

Abstract

BackgroundVisceral leishmaniasis (VL), caused by an intracellular parasite Leishmania donovani in the Indian subcontinent, is considered to be anthroponotic. The role of domestic animals in its transmission is still unclear. Although cattle are the preferred blood host for Phlebotomus argentipes, the sandfly vector of VL in the Indian subcontinent, very little information is available for their role in the disease transmission. In this study, we examined domestic cattle for serological and molecular evidence of Leishmania infection in a VL-endemic area in Bangladesh. Blood samples from 138 domestic cattle were collected from houses with active or recently-treated VL and post-kala-azar dermal leishmaniasis patients. The presence of anti-leishmanial antibodies in serum was investigated using enzyme-linked immunosorbent assay (ELISA) and then with direct agglutination tests (DAT). Nested PCR (Ln PCR) was performed to amplify the ssu-rRNA gene using the DNA extracted from Buffy coat. Recently-developed molecular assay loop-mediated isothermal amplification (LAMP) was also performed for further sensitive detection of parasite DNA.ResultsIn this study, 9.4% (n = 13) of the cattle were found to be positive by ELISA. Of the 13 ELISA-positive cattle, only four (30.8%) were positive in DAT. Parasite DNA was not detected in either of the molecular assays (Ln PCR and LAMP).ConclusionsThe study confirmed the presence of antibodies against Leishmania parasite in cattle. However, the absence of Leishmania DNA in the cattle indicates clearly that the cattle do not play a role as reservoir host. Similar study needs to be undertaken in the Indian subcontinent to determine the role of other domestic animals on which sandflies feed.

PCR-Based Detection of <i>Leishmania donovani</i> DNA in a Stray Dog from a Visceral Leishmaniasis Endemic Focus in Bangladesh

“…The presence of L. donovani DNA in the blood sample from a stray dog in our study supports the findings of a previous study in Sri Lanka [16], Sudan [11], and India [19]. In a more recent study in Nepal, Leishmania DNA was found in several domestic animals such as goats, cows and buffaloes from an endemic area several months after the active transmission season [4], but there was no evidence of Leishmania DNA in domestic cattle in Bangladesh, although the cattle were seropositive for leishmaniasis [1]. However, other domestic animals, such as goats, buffaloes and wild animal (foxes) remain to be investigated.…”

“…These findings strengthen the idea of an animal reservoir for L. donovani in Bangladesh. A recent study [1] detected antibodies against the Leishmania parasite in cattle from an endemic area of Bangladesh, but no parasitic DNA was found by PCR. This result suggests that cattle do not play a role as a reservoir host, but further studies on other domestic animals need to be conducted.…”

Molecular and Serological Evidence of Leishmania Infection in Stray Dogs from Visceral Leishmaniasis–Endemic Areas of Bangladesh

“…26 Our observations of anti-Leishmania antibodies and Leishmania DNA in blood samples obtained from stray dogs corroborate the findings of previous studies in Sri Lanka, 10 Sudan, 2 and India. 12 In Bangladesh, cattle that are seropositive for leishmaniasis have been found, but there is no evidence of Leishmania DNA, 13 suggesting that cattle do not play a role as reservoir hosts. In a recent study, Leishmania DNA was detected in a single (1.2%) dog among 85 stray dogs using DNA extracted from whole blood spotted on filter paper.…”

“…Recently, antibodies against the Leishmania parasite were detected in cattle from an endemic area of Bangladesh, but no parasitic DNA was detected by polymerase chain reaction (PCR). 13 In our recent study, Leishmania DNA was detected in one stray dog from VL-endemic areas of Bangladesh.…”

Leishmaniasis: A Review on Parasite, Vector and Reservoir Host

“…Many of the leishmania species infecting human are zoonotic, having a complex variation in domestic and wild mammal reservoir hosts; while, other species of the parasite are anthroponotic, having human-to-human transmission in the presence of the vector [9]. Leishmania donovani is usually considered to be an anthroponotic parasite though studies reported the presence of parasite or circulating antibodies against the parasite antigens in domestic and wild animals of India and East [8,14]. The global distribution of each of Leishmania species determines the type of disease that occurs in an area.…”