In Malaria World last week there was an article researching the uptake of intermittent preventive treatment in pregnancy (IPTp) in six sub-Saharan countries (Xu et al, 2024). This is just one example of many research papers that examine uptake of malaria preventative treatment and try to propose how to increase it. This would seem to suggest that the target populations are not enthusiastically participating in these programmes.
My Blog post from last week reported a correlation between incidence of malaria in 0-5 year olds and their mother’s participation in IPTp programmes during pregnancy. Clearly there is no mechanism by which this could be the cause so it is one case in which correlation is not linked to causation. The purpose of IPTp is to prevent malaria during pregnancy. So what evidence is there that IPTp is effective?
The introduction of the Xu paper references the WHO World Malaria Report, 2023, and states malaria is mostly found in tropical countries and poses the greatest risk to vulnerable populations, such as pregnant women, young children, international tourists, and people living with HIV. The report claims that in 2022, 35% of pregnant women in susceptible African nations were ‘exposed to malaria infection’. However, 22% of the population as a whole in these countries were exposed. There is greater risk, but could it be explained by other factors?
The increased incidence of malaria during pregnancy was shown in 1983 by Brabin in An analysis of malaria in pregnancy in Africa. But women in all countries suffer from additional health issues while pregnant. Is it surprising that potentially malnourished pregnant women in poorer countries where ‘malaria’ is a commonly diagnosed illness might be more susceptible?
Based on this increased susceptibility, the WHO in 2012 updated recommendations that IPTp treatment with sulfadoxine-pyrimethamine (SP) should be administered as part of ante-natal care in susceptible countries at every ante-natal visit starting as early as possible in the second trimester, provided that doses are at least one month apart. The WHO claims sulfadoxine-pyrimethamine (SP) is safe and effective for pregnant women, a claim somewhat doubted by US FDA who grade it Pregnancy category C. Risk not ruled out: Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.
So why are there no well-controlled studies in humans showing a benefit? No evidence is provided in the Xu et al paper, or any other research article I have reviewed, that there are benefits to pregnant women from administration of this toxic medication. I wonder why these research results are not available?