Dr. Barthlomew Ondigo is a Fellow at the African Academy of Sciences with growing expertise in the immunology of infectious parasitic diseases and global health. Outside of his current position as a researcher he teaches at Egerton University in the Department of Biochemistry and Molecular Biology in Nakuru, Kenya.
- What is placental malaria and how is it acquired?
This is malarial infection in the placenta. It is characterized by sequestration of Plasmodium falciparum-infected erythrocytes and infiltration of immune cells within the inter-villous spaces of the placenta. It is acquired when malaria parasites expressing a particular type of variant surface antigen (VAR2CSA) is exported to red blood cell membrane, which facilitates binding of infected erythrocytes to an adhesion receptor, chondroitin sulfate A, (CSA) on the placental tissue.
- What are the factors that predisposes a person to acquire placental malaria?
Some of these factors include:
- Pregnant women are at greater risk of malaria infection and of symptomatic malaria disease than non-pregnant adults.
- Placental malaria is most frequent in the first pregnancy (primigravid women).
- Maternal age may be an independent risk factor; as younger pregnant women have been found to be more susceptible to malaria in some settings.
- HIV infection increases susceptibility to malaria.
- Utilization of insecticide-treated bed nets
- What is the prevalence rate of placental malaria in Africa?
World Health Organization (WHO) reported in 2018 alone that 11 million pregnancies in sub-Saharan Africa were at risk of malaria.
- How big of a problem is placental malaria in the continent?
Placental malaria is a serious public health problem in sub-Saharan Africa and about 10,000 women and 200,000 babies die annually because of malaria in pregnancy. Most of these deaths are caused by Plasmodium falciparum, which is found in tropical and subtropical regions. Approximately 25 million pregnant women in sub-Saharan Africa live at risk of P. falciparum malaria infection.
- How does somebody acquire immunity to placental malaria?
Women who have malaria during pregnancy develop Plasmodium falciparum-specific antibodies. These maternal antibodies against VAR2CSA protect them from placental malaria in subsequent pregnancies. Hence, placental malaria is mainly a problem during the first few pregnancies.
- What is your project about?
I am comparing cells ( fetal macrophages) in the placenta of malaria infected versus uninfected women.
- What impact do you hope your project will achieve on placental malaria?
These studies will provide a strong foundation for exploring cell responses, their immunological mechanisms, and gain novel insights into how the cells cause placental malaria. This study will also provide a basis for exploring cell responses and their immunological mechanisms in placental malaria.