Transmission

In the peri- and post-elimination settings, a strong Kala Azar surveillance framework will be required to measure ongoing transmission, and ensure outbreaks do not occur. Xenomonitoring involves measuring the incidence and prevalence of parasite infection in local vector populations. It is a non-invasive, ethically uncontentious method of monitoring transmission in elimination settings, and may be more cost-effective than collecting human samples.

Xenomonitoring has been used successfully to assess elimination endpoints for lymphatic filariasis (LF) in several countries, but requires technical development for Kala Azar. In this project, we will (1) optimise a real-time quantitative polymerase chain reaction assay to detect specifically the metacyclic forms of Leishmania donovani in P. argentipes, and (2) deploy it in a proof-of-concept pilot study to assess feasibility, scalability, and cost-effectiveness of xenomonitoring as a passive surveillance system.

Subramanian et al. 2017. 'Application of a household-based molecular xenomonitoring strategy to evaluate the lymphatic filariasis elimination program in Tamil Nadu, India'. PLoS NTD 11(4): e0005519.

Rao et al. 2016. ‘Programmatic use of molecular xenomonitoring at the level of evaluation units to assess persistence of lymphatic filariasis in Sri Lanka’. PLoS NTD 10(5): e0004722.

Lau et al. 2016. ‘Lymphatic filariasis elimination in American Samoa: evaluation of molecular xenomonitoring as a surveillance tool in the endgame’. PLoS NTD 10(11): e0005108.

Tiwary et al. 2012. 'Prevalence of sand flies and Leishmania donovani infection in a natural population of female Phlebotomus argentipes in Bihar State, India'. Vector Borne Zoonotic Diseases, 12(6): 467-472.

LSHTM

Prof Mary Cameron

Ms Shannon McIntyre

Dr Matthew Rogers

Ms Giorgia Dalla Libera Marchiori

RMRI

Dr Pradeep Das

Dr Vijay Kumar

London School of Hygiene and Tropical Medicine (LSHTM)

Rajendra Memorial Research Institute of Medical Sciences (RMRI)

Bill and Melinda Gates Foundation (BMGF)