Kamran, an individual whose unwavering dedication has left a profound mark on the global health community and the pursuit to end all…
In this post, we speak to the authors of a recent PLOS Neglected Tropical Diseases article, Cholera past and future in Nigeria: Are the Global Task Force on Cholera Control’s 2030 targets achievable?, about the story behind the research. The paper was written by Gina E. C. Charnley, Sebastian Yennan, Chinwe Ochu, Ilan Kelman, Katy A. M. Gaythorpe, and Kris A. Murray.
What led you to decide on this research question?
There is an abundance of global health goals and targets, including the Global Task Force on Cholera Control 2030 Roadmap. These goals help countries move towards a common global target; however, they can often be forgotten, or fail to bring about change and improvements on the scale to which they aspire.
Quantitative epidemiology often does not take policy or global initiatives into account, with qualitative research focusing more on this. Nevertheless, quantitative research should strive to ultimately improve public health and by incorporating quantitative analysis into global health targets and initiatives we can further understand how and if we can reach these goals, and what more needs to be done.
Could you talk us through how you designed your study? What was important for your team as you created the study team?
We had completed several quantitative modelling exercises in recent years looking at climate and social extremes and their impact on cholera outbreaks in Africa. Our aim here was to use these models and expertise to understand what these findings could teach us about future cholera conditions in Nigeria, a country which we had focussed on in detail. We wanted to use our results to understand how this could inform the achievability of one of these global initiatives, in this case the GTFCC targets in Nigeria in quantitative terms, identifying priority areas and thresholds to focus on to meet the 2030 targets.
What challenges did you encounter during your study?
A major issue in all cholera research is a lack of data and heterogeneity among datasets and reporting. There are issues in cholera data, particularly in terms of under-reporting, as a large number of people will be asymptomatic or only have mild symptoms, therefore they do not seek formal medical assistance, are not being tested and therefore not reported.
Additionally, our understanding of climate and cholera is still in its elementary phases and is an evolving field. Caution must be taken at this stage when interpreting any results of climate and cholera research, as we continually try to understand the links and if some are more important than others.
What did you find most striking about your results? How will this research be used?
I think the most striking finding was the scale in the difference found in our results between geographic regions. Changing environmental and social conditions were felt differently in terms of cholera in the north of Nigeria (generally less developed and more rural), compared to the south, with a very clear split in the behaviour of these relationships. The less developed north of Nigeria projected good improvements in cholera transmission with more optimistic future scenarios (climate change mitigation and socio-economic development). Comparatively, in worsening future conditions, the north was relatively unchanged, perhaps due to its already high cholera transmission, whereas the south saw significant increases in cholera. The results show the importance of at least maintaining the development and peace achieved in southern Nigeria and working to prioritise development and stability in northern Nigeria as a public health priority.
What further research questions need to be addressed in this area?
As discussed, we fundamentally do not have a good enough understanding of how climate impacts cholera to make robust projections about the future. However, the impact of social conditions such as armed conflict, displacement, access to WASH and poverty appear to have a much stronger and clearer influence. Continued research to understand how we can prioritise areas at risk is very important in addressing these significant global issues and challenges, while continually working to understand how the climate influences cholera.
Why did you choose PLOS Neglected Tropical Diseases as a venue for your article?
PLOS NTDs regularly publishes cholera research of high quality and impact, and its readership has a clear interest in the disease. We believe that cholera has become a more neglected disease in Africa in recent years, particularly in the face of recurrent Ebola outbreaks and the COVID-19 pandemic. However, as the 7th cholera pandemic continues, with little signs of significant regression, continued effort, resources and further understanding of the disease are needed. How and where to tackle the challenge of inequity in term of cholera transmission are vital for resource allocation, and we believe that PLOS NTDs is an ideal platform to do that, with its strong NTD and global health focus.