From York to Malawi and back: The first UK based sero-prevalence study of Human T lymphotropic virus 1/2 in paired mothers and children living in Malawi

Overview

Human T lymphotropic virus type 1 (HTLV-1) chronically infects human immune cells and can lead to debilitating disease or blood disorders. HTLV-1 is commonly found in the West Indies and Southern Japan. Sub-Saharan Africa is thought to be a high endemic area, but it is not mapped sufficiently to allow the promotion of effective HTLV prevention programmes, such as ante-natal and blood transfusion screening. This collaboration between the University's Centre for Immunology and Infection (CII) and the Epidemiology and Cancer Statistics Group (ECSG) in the Department of Health Sciences set out to test 1,000 paired Malawian mother-child blood samples to gather data on incidence, transmission rate and co-infections and malignancies. 

The prevalence of HTLV and HCV was tested in paired plasma samples from a study cohort of 418 mothers and children collected between 2006 and 2010 at Queen Elizabeth Hospital in Blantyre, Malawi, South-East Africa using an ELISA assay. The results showed that two mothers and one child were HCV positive and that twenty-seven mothers were HTLV-1/2 positive. Of these, three (11%) mothers had HTLV-1 and eight (30 %) were HTLV-2 positive. The form of HTLV in the remaining sixteen (59%) mothers could not be determined. Of the corresponding children, one had an undetermined form of HTLV, one was HTLV-2 positive and one tested positive for both forms.

The detected low prevalence of HCV amongst healthy mothers confirms published data. The high rates of HTLV-2 and the number of indefinite results for the form of HTLV were unexpected and signal a different distribution of HTLV-2 in Southern Africa than that previously reported. It is possible that the indeterminate tests indicate the presence of HTLV-3 or 4. A polymerase chain reaction DNA sequencing of ELISA positive samples is needed to allow a more sensitive detection of HTLV positive samples. With the help of collaborators DNA from these mother-children pairs has been secured and is ready for testing. An article on the prevalence of HTLV and HCV in healthy women and their children in Malawi is being written which will also include a map of HCV and HTLV distribution in Africa as known to date.

Outputs

Publications

• Fox, J.M., Newton, R., Bedaj, M., Keding, A., Molyneux, E., Carpenter, L.M., Martin, F., & Mutalima, N. (2015) Prevalence of hepatitis C virus in mothers and their children in Malawi. Tropical Medicine & International Health, 20 (5), DOI: 10.1111/tmi.12465