A maternal and child health clinic on the Thai-Burma border where Dr Freya Fowkes is looking at immunity in pregnant women.
More than three billion people remain at risk of contracting the deadly disease, with young children amongst the most vulnerable.
At Burnet, we are responding by trying to develop an effective vaccine and also new antimalarial drugs to tackle the emerging threat of drug resistance in parts of South-East Asia to the most effective frontline antimalarial drug, artemisinin.
In the Summer edition of IMPACT we explored the range of malaria research and public health programs underway at Burnet. Here is an excerpt of that feature article.
Malaria is an infectious disease caused by a parasite Plasmodium that is transmitted via the bite of infected mosquitoes. The parasites multiply in the liver and then infect red blood cells.
Malaria in pregnancy
Head of the Malaria and Epidemiology Group, Dr Freya Fowkes, with colleagues at Burnet, made a major discovery in finding out how the immune system of pregnant women responds to malaria, which may help the development of long-lasting vaccines to protect pregnant women against malaria.
The research showed immune responses to different malaria proteins in pregnancy wane relatively quickly, so they may not be effective in providing long-term protection against the disease.
“There is hope though – we also found that the immune response to one pregnancy-specific protein lasts for many years, which can help fight-off malaria infections in the placenta during pregnancy,” Dr Fowkes said.
“These findings are a major advance in the quest for a vaccine against malaria in pregnancy, they suggest that a long-lasting, pregnancy-specific vaccine could be developed to protect pregnant women and their babies against the devastating consequences of malaria.”
Low birth weight is responsible for about 800,000 infant deaths a year and is major issue for malaria-infected pregnant women and. It’s estimated about 125 million women living in malaria endemic areas become pregnant every year, further highlighting the urgent need for a vaccine.
Co-Head of Burnet’s Centre for Biomedical Research, Professor James Beeson and his team, with collaborators at the Papua New Guinea Institute of Medical Research, have also made progress in vaccine development by looking at particular malaria proteins and the role they play in the body’s immune response to malaria.
Published in the Journal of Immunology, the study systematically evaluated dozens of malaria proteins that could be important targets of human immunity.
“We started with over 90 proteins initially, then narrowed the focus to 46. We then performed detailed studies of immune responses to all of these proteins in 200 Papua New Guinean school children,” Professor Beeson explained.
“We identified several proteins that appear to be major targets of protective immunity and are strong candidates for vaccine development.
“These ‘new’ vaccine candidates were much more strongly associated with protective immunity than vaccines currently in clinical trials.”
Professor Beeson pointed out that these identified proteins may advance the development of effective vaccines and help develop tools to monitor immunity, identify populations at high risk, and track changes over time in communities with malaria.
New drugs urgently needed
Dr Paul Gilson, alongside Burnet Director and CEO, Professor Brendan Crabb, is investigating how malaria parasites infect human red blood cells, where they grow and multiply, and how the parasite-infected red blood cells avoid the immune system.
“We are specifically trying to discover how the malaria parasite reads the red blood cell surface and then makes the decision to invade it. Once inside, the malaria parasite synthesises sticky, Velcro-like proteins and sends them out to the surface of the red blood cell causing the cell to bind to the walls of blood vessels,” Dr Gilson explained.
“This keeps the infected blood cells away from the spleen, a blood-filtering organ that can destroy the infected cells.”
Over the next few years, Dr Gilson hopes to develop drugs that block the parasite’s capacity to invade red blood cells and to export the Velcro-like proteins.
Home-based diagnosis in Papua New Guinea
Burnet’s Centre for International Health is looking at ways to best implement interventions to try and manage malaria on a community level in PNG.
International health specialist Lisa Davidson trained 200 community-based volunteers for the Home-Based Malaria Management project in Kokopo, East New Britain, a province on an island east of the PNG mainland.
The project, is exploring the viability of village-based volunteers to be the first point of contact for diagnosis and treatment of malaria in pregnant women and children under five.
“Early diagnosis and treatment of malaria significantly reduces the morbidity and mortality of the disease, particularly in children and pregnant women,” Ms Davidson said.