London School of Hygiene & Tropical Medicine

Tell us about your current research

My current research, funded by the U.S. National Institutes of Health (NIH), focuses on mapping the prevalence of zero-dose children, delays in measles vaccination, and the risk of measles outbreaks in The Gambia. I am also examining how geographic accessibility of immunisation clinics affect the timely uptake of measles vaccines and the occurrence of zero-dose children. Additionally, my research aims to explore the associations between under-vaccination, unvaccinated populations, herd immunity, and the risk of measles outbreaks.

How did you first become interested in vaccines?

As a paediatrician who trained and worked in West Africa for over a decade, I’ve seen first-hand the devastating impact of vaccine-preventable diseases on child health. Clinically, I had the expertise to treat infectious diseases and manage life-threatening complications, but even as a medical student, I knew I wanted to focus on preventing these diseases rather than just treating them. I quickly realised that, given the many challenges facing health systems in low- and middle-income countries, accurately measuring the burden of disease and understanding the factors behind vaccine-preventable illnesses would be go a long way. My interest in vaccine research stems from a desire to generate evidence that could help drive the effort to prevent these diseases.

What do you find particularly interesting working as a member of the Vaccine Centre?

Having served on the Management Committee of the Vaccine Centre at LSHTM, I’ve come to appreciate that, despite our diverse research areas, expertise, and cultural backgrounds, we all share the same goal: making a real-world impact through vaccine research. It’s this shared sense of purpose, combined with the centre’s diversity, that I find both exciting and inspiring.

Where do you think your research will take you?

I wouldn’t claim to predict the future, but I hope my research will help change how we think about childhood vaccination systems. While significant progress has been made in measuring vaccination uptake, coverage, and, more recently, zero-dose children, I believe we need to go beyond coverage alone—especially for vaccines like the hepatitis B birth dose and the measles vaccine. Timeliness is critical, and I aim to contribute to research that explores how untimely vaccination might influence factors like measles outbreak potential or mother-to-child transmission of hepatitis B.

What are some of the real-life implications of your work?

To effectively achieve global immunisation goals like those outlined in Immunisation 2030, we need fine-scale spatial data. Such data allows us to pinpoint disparities in vaccination coverage, timeliness, and herd protection against diseases like measles at a country level. Additionally, understanding how geographic accessibility to immunisation clinics, particularly in remote hard-to-reach areas, influences vaccine uptake is key. My research is contributing valuable data in this area, which I believe has significant real-world implications.

What do you like doing in your spare time?

I’m quite a private person, so I enjoy spending most of my free time with my wife, daughter, and son. On weekdays, I start my mornings with an hour of jogging or walking before the day’s busy schedule kicks in. I’ve also been a football fan for about three decades, so I often spend my weekends indoors watching English Premier League matches.

What would you consider an interesting fact about yourself?

An interesting fact about me is that I can name all the host countries and winners of the FIFA World Cup since 1990. I’m a massive football fan and have watched every World Cup since then.

How can people get/ stay in touch with you?

On X @drwariri and LinkedIn.