Keli Gerken, University of Liverpool
Project: Uncovering endemic Rift Valley fever patterns at the human-animal-environmental interface to model transmission in Kajiado County, Kenya.
Rift Valley fever virus (RVFV) is a zoonotic virus transmitted by mosquitos. As cattle, sheep, and goats increase local viral activity, humans can also be exposed by contacting infected livestock fluids.
If livestock infections are controlled, public health risks are reduced, but in all species, RVFV is hard to differentiate from other diseases without targeted sampling and testing.
Cases are increasingly detected between large outbreaks, but the extent is unknown because current testing systems are not designed to capture them. This perpetuates a biased understanding of epidemiology. With potential for severe human disease, economic impact on livestock, and no human vaccine option, current understanding of how RVFV moves through populations in hotspots does not reflect the global importance of the disease.
This study aims to uncover local outbreaks in humans and animals to understand the extent of endemic transmission and risk. We will also collect livestock movement and vector data to use in adapting a simulation model made for another livestock disease to determine what factors are important for RVFV spread. Finally, since human behaviours impact risk and control of disease, we will integrate a qualitative study that summarizes the community’s perspective of barriers and facilitators to controlling livestock diseases.
ORCID 0000-0001-9337-2409
Peter Johnston, University of Liverpool
Project: Transmission dynamics for invasive Non-Typhoidal Salmonella serovars in Africa (TiNTS).
Salmonella bacteria are usually found in food, water, people or animals. In humans they cause infection when they enter through the mouth and travel to the gut. Usually this causes diarrhoea, but certain types of salmonella can escape the gut, leading to a serious infection of the bloodstream or lining of the brain. These "invasive" salmonellae are found most often in Africa.
The most common type of invasive Salmonella bacteria is Salmonella Typhimurium ST313 ("ST313"). ST313 bacteria are defined by a shared genetic makeup. It may be that the genes ST313 expresses give it a better chance to survive inside people. Unlike other salmonellae, we do not know where ST313 comes from. I suspect that it may reside in humans and water.
I want to find out how ST313 and other salmonellae circulate within households in Africa. I will follow households in Malawi over time. I will test stool samples from each member of the household over one month. I anticipate that in some households, there will be a new Salmonella infection during follow-up. I will carry on following these households to see whether the Salmonella is passed to others in the household.
Understanding how Salmonella passes between people will allow us to identify ways to break the cycle of transmission, and ultimately tackle the diseases that salmonellae cause.
ORCID 0000-0001-9400-6339
Charlotte Snead, Liverpool School of Tropical Medicine
Project: Understanding risk factors for progressive chronic kidney disease in Malawi to inform interventions for earlier detection and prevention.
Worldwide, the number of people living with long-term health conditions, including chronic kidney disease (CKD), is increasing. CKD is usually asymptomatic in early stages but can progress to advanced disease, including kidney failure, and is associated with significant morbidity and mortality.
In low-income countries of sub-Saharan Africa, including Malawi, treatments for kidney failure are not yet widely available and are prohibitively expensive. It is therefore vital to:
a. Prevent development of CKD in the first place
b. Detect CKD earlier, so that more cost-effective treatments can be given to slow progression There is little evidence on factors that drive CKD progression in Malawi, or on interventions that may be cost-effective for improving detection and slowing disease progression in this setting.
This PhD will address these knowledge gaps, through the following aims:
- Determine the mortality associated with CKD, and the risk factors driving its development and progression in Malawian adults
- Investigate the feasibility, applicability and predicted impacts of different models for integrating CKD screening and prevention strategies into health services in Malawi
- With patients, carers, healthcare workers and policy makers, evaluate the acceptability of different models for CKD screening and prevention in Malawi, and explore potential barriers to their implementation.
ORCID 0000-0002-3603-3926
Jack Milln, University of Liverpool
Project: A cohort study to determine the prevalence of non-communicable diseases (NCDs) in pregnant women in Malawi, and develop a complex intervention to improve clinical care.
Maternal and neonatal mortality remain unacceptably high in Malawi. Whilst ‘direct’ causes of maternal mortality such as bleeding and obstructed labour are well described, little is known about the contribution of ‘indirect’ causes associated with pre-existing NCDs such as diabetes, hypertension, chronic kidney disease (CKD) and anaemia.
These conditions often deteriorate during pregnancy due to the physiological changes that occur, and they identify those women at risk of future cardiometabolic complications. These NCDs are often studied in isolation despite clustering in vulnerable populations and their synergistic action. In this study we will therefore collect data on a number of NCDs in a well-characterised cohort of pregnant women and explore their impact on important pregnancy outcomes, and follow them into the postpartum period.
NCDs are not binary entities but usually confer a graded risk of adverse pregnancy outcomes with a spectrum of disease from mild alterations in variables (such as blood pressure and blood glucose) to overt disease. It is widely established that overt disease caused by established NCDs should be managed accordingly. The clinical importance of NCDs at the milder end of the spectrum in resource-limited settings is debatable; this study will add to that growing body of evidence.
Pregnant women with NCDs rarely receive quality clinical care across the African region. Where guidelines do exist ,they are usually repurposed from high-income settings due to the paucity of local evidence in this area. They are often not implemented due to health system constraints such as organisation of services and workforce/resource availability. We will therefore explore the barriers to effective clinical care and co-design a complex intervention appropriate to the low-resource setting for use in a future trial setting.
ORCID 0000-0002-3464-6577
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