Cyclic reemergence and geographical spread of Rift Valley fever

I am an infectious diseases epidemiologist and a one health expert undertaking a one health postdoctoral fellowship at the School of Public health at University of Nairobi in collaboration with the university of Liverpool under the HORN project. I am also visiting scientist at ILRI One Health Center.  

In the last fifteen years I have been involved in collaborative one health research between the government, research and academic institutions in Kenya. My focus has been on capacity building, policy development and implementation research on emerging infectious zoonotic diseases at the human-animal-environmental interphase.

These efforts have realized greater impact on design of effective surveillance and response strategies to disease outbreaks while providing evidence that is integral in national animal and health sector planning for control of zoonotic diseases in Kenya.

In the last decade I have been focused on unravelling the cyclic reemergence and geographical spread of Rift Valley fever (RVF) and other arboviral zoonoses from high risk low risks with naïve human and animal populations in Kenya.

The epidemiology of RVF is determined by intricate transmission dynamics that involve a vector-host-environment triad, hence defining the one health paradigm. The risk of human infection is enhanced by close interaction with animals, while emergence of mosquitoes is driven by flooding and habitat suitability.

RVF is a priority zoonotic diseases (PZD) in Kenya based on ability to cause epidemics, economic losses and severity of infection in humans. Since May 2018 to 2019, Kenya has experienced intermittent but multiple small RVF outbreaks in high risk counties, there has been however unexpected outbreaks in low endemic areas.  

I am establishing a small scale human-animal integrated One Health Surveillance System toenhance national decision support tools that will lead to faster detection, effective response, prevention and targeted control of RVF during the interepidemic periods.

RVF is a classic zoonotic disease where One Health approaches can be essentially employed and practiced. The study will strengthen one health research capacity and workforce by harnessing the synergy in genomic and spatial epidemiology, public health, entomology and social sciences. It shall allow the realization of one health practice that can seamlessly be integrated into decision making by human and animal policy-makers at the national and global level.   

The Soulsby fellowship and funding will greatly support the successful completion of this project which ultimately will provide me with an excellent opportunity as an emerging global leader in one health. Using the findings I will engage one health practitioners, researchers to find solutions to local problems for improved livestock health, food security and overall well-being of peoples health.

There are challenges in effective control of RVF outbreaks are due to lack of knowledge of risks and poor preventative practices among the populations. The scarcity of prevalence and genetic diversity data and lack of rapid diagnostics hampers the early detection and control.  Despite the availability of the livestock vaccine, there is no known human vaccine or therapies.

RVF is one of the most ideal example of a zoonotic disease where integrated multisectoral One Health approaches can be used to overcome challenges in development of effective and replicable control strategies that can be implemented by policy-makers.This study may provide guidelines for targeted and cost effective vaccine uptake programs  

In addition to my research on infectious diseases epidemiology, I act as a bridge between researchers, academia and the government by providing technical advice to the Zoonotic Disease Unit in Kenya. The ZDU is the government one health office that collaborates with UN FAO, OIE and WHO in development of national prevention and control strategies of zoonotic diseases and  implementation of other GHSA action packages that include antimicrobial resistance (AMR) .  

As a soulsby one health ambassador, I will disseminate information on global health by capacity building of frontline epidemiologists under the CDC FELTP and FAOs ISAVET programmes. I will also use this fellowship to bolster my efforts as the country ambassador for the RSTMH in Kenya by identifying networks, sharing challenges or successes in tropical medicine and translating one health research into policies.   

Mark Nanyingi