A new research has found that HIV and malaria combine to adversely affect pregnant women and their infants.
University of Toronto researchers have exposed the origin by which pregnant women guard themselves against malaria and have also discovered how the HIV virus works to counter this defence. The research could lead to superior vaccines for pregnant women in malaria-ravished regions.
Malaria is a parasitic disease spread by mosquitoes that kills more than one million people every year. While the disease by and large hits children, malaria also brutally affects pregnant women, particularly during their first pregnancy, accounting for a projected 400,000 cases of severe anaemia and 200,000 infant deaths each year.
With the recent awareness that HIV further worsens pregnancy-associated malaria (PAM) there is a pressing need to comprehend these diseases during pregnancy and turn this knowledge into effective therapies.
Until now the mechanisms by which pregnant women defend themselves against malaria and how HIV impairs this defence have been unknown, but a paper published in PLoS Medicine (Public Library of Science) pins down how the virus targets the immune response in pregnant women.
"PAM can be a deadly condition that leaves mothers and their children particularly vulnerable. We set out to understand how women acquire protection against malaria during pregnancy and how HIV infection impairs that protection. By understanding how they lost protection in the face of HIV we learned how they acquired protection against malaria in the first place," says Professor Kevin Kain, an infectious disease specialist and lead author of the study.
PAM occurs when red blood cells infected with malaria parasites congregate in the placenta resulting in harm to both mother and the budding baby. First-time mothers are predominantly prone to PAM whereas women in subsequent pregnancies become protected against PAM. But HIV virus leads to the hammering of protection and makes them as vulnerable as first-time mothers.
To discover how HIV affects PAM, Kain and his team collected samples from women in the first pregnancy as well as from women in their subsequent ones living in the Kenyan region where malaria is widespread. The researchers demonstrated that protection to PAM is arbitrated by a unique type of antibody that allows women to preferentially clear the parasites in their placentas.
The results showed that HIV-infected women lose these antibodies and again become susceptible to the negative effects of PAM.
The findings, according to Kain, may help in the development of superior PAM vaccines.
"This is only the first step in creating therapeutics to treat this devastating disease. We hope to help translate this knowledge into more effective vaccines designed to generate these types of protective antibodies," Kain said.