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Dr Peter Keiyoro (University of Nairobi, Kenya) & Dr Josephine Ngunjiri (University of Embu, Ken


Dr Peter Keiyoro (University of Nairobi, Kenya)

Dr. Josephine Ngunjiri ( University of Embu, Kenya)

Interview by Marianne Comparet & Kamran Rafiq (ISNTD)

Tungiasis is a debilitating parasitic disease caused by the flea Tunga penetrans burrowing into skin, affecting poor communities in Africa and Latin America disproportionately. Secondary infections from tungiasis lesions can lead to severe bacteremia, tetanus and gangrene, with significant implications in terms of disability. Despite prevalence reaching up to 50% in certain communities, tungiasis is often overlooked as a severe public health concern, even among healthcare staff. In this interview, the ISNTD speaks to Dr. Peter Keiyoro and Dr. Josephine Ngunjiri, from the Universities of Nairobi and Embu in Kenya, who have been working tirelessly in the field to quantify the burden of this disease in Kenya, train healthcare staff to recognise and address this disease appropriately and raise awareness and advocacy globally for this extremely neglected disease.

It's a great pleasure to meet you and welcome you to the ISNTD. Could you give us a brief overview of your training, background and current research?

I am Dr. Peter Keiyoro, currently based at the University of Nairobi, Kenya. I have training in biological sciences, having specialized in zoology and science education. I have a background in teaching biological sciences and research in neglected tropical diseases, with a strong focus on the impact of tungiasis on school age children.

I entered the field of public health when I developed curricular materials for healthcare providers in Kenya pursuing the Postgraduate Diploma in the Management of Sexually Transmitted Infections (including HIV-AIDS) at The University of Nairobi. In more recent times, I have also attended a short training course on Health Metrics and Evaluation in Global Burden of Disease offered by the Institute of Health Metric and Evaluation (IHME) of Washington University, USA, under the guidance of Prof Christopher Murray. This has allowed me to be an active collaborator in data collection and analysis in the Global Burden of Disease and I have also contributed extensively in several publications (NACET) in this field as well as co-published my work in tungiasis.

My recent research focuses on the highly neglected disease: tungiasis. My personal experience as a tungiasis casualty during my childhood and studies about the impact of tungiasis on school age children in Kenya since 2009 has given me great impetus to continue engaging in research projects related to the burden of disease caused by tungiasis. Our first project focused on the health status among ageing populations affected with tungiasis and on soil factors influencing the prevalence of tungiasis in endemic areas.

The second project was geared towards comorbidities related to tungiasis among the infected children aged 5-14 years.The third project will focus on mapping the disease including investigating the burden of the disease, prevalence and incidences in specific areas in Kenya, sub-Saharan Africa and on a global level.

Dr. Josephine Ngunjiri is a co-principal researcher in the above projects. She is trained in both Science Education as well as Applied Parasitology and Tropical and Infectious Diseases from the University of Nairobi. She has also attended the short training on Health Metrics in Global Burden of Disease offered by Institute of Health Metrics and Evaluation of Washington University. Hence she is an active collaborator in data collection on the Global Burden of Disease and has also contributed extensively in several publications in this area as well as in her work in tungiasis.

What is the prevalence of tungiasis worldwide? What are the hot spots, both in terms of countries/regions, but also populations at risk?

Tungiasis mostly occurs in Latin America, the Caribbean and sub-Saharan Africa where it mainly affects the low income communities. In Kenya for example, although mapping of this disease has not been done, it is known to be prevalent in Murang’a, Nyeri, Kwale, Malindi, Kericho, Narok, Emuhaya, Meru and Kakamega counties where it is widespread among resource-poor communities. It has been estimated that 2.7 million people are at risk of being infected with tungiasis in these stable endemic foci in the affected counties in Kenya. Previous studies also indicated that tungiasis had an age-specific peak with the highest prevalence being among the school age children aged 5-15 years and the elderly.

The presence of tungiasis in Africa can be traced back to the 17th century during which T. penetrans is postulated to have been introduced to West Africa from South America. In 1872, ships carrying infested ballast sand from Brazil arrived in Angola where the disease caused severe morbidity and was described as second cause of mortality after small pox in the 19th century. The disease is also thought to have spread in Sub-Saharan Africa through trade and military routes reaching Kenya, Zanzibar and Madagascar.

In other areas in Africa, for example in Western Nigeria, the prev