This is the third piece continuation of the countdown to 50 things you did not know about Malaria in Pregnancy! as featured in our current issue of HALA Magazine (Malaria edition).
Determinants of the impact of Malaria during a pregnancy
Factors that influence the severity of a malaria infection include the transmission rates, use of chemoprophylaxis, maternal age, number of previous pregnancies, host genetics and nutrition, and concurrent infection with human immunodeficiency virus (HIV).
In areas where malaria transmission is low or only occurs in epidemics, pregnant women are at a much high risk of severe complications such as cerebral malaria, and even death.
Whereas in areas where malaria transmission is stable, the adult-acquired immunity against P. falciparum may keep symptoms from showing e.g. malaria without fever.
However, the eventual outcome for women in malaria-dense regions is due to the presence of parasites in the placenta which causes anaemia in the mother and low birth weight (LBW) in the child.
30. BUT IF?
Additionally, it has been observed that a young maternal age (< 24 yrs), poor nutrition and genetic factors are significantly associated with the adverse effects of malaria in pregnancy.
Concurrent infection of malaria and HIV in pregnancy has been associated with the presence of more parasites in the blood and those hidden within the placenta.
The higher parasite density causes increased frequency of clinical malaria, severe anaemia, and amplifies risk of adverse birth outcomes.
This occurs primarily because of the impaired ability of the white blood cells to directly fight off the parasite
HIV positive women also notably have a reduced level of specific antibodies associated with protection against malaria in pregnancy.
Malaria in Pregnancy Research… just some NERDY DETAILS
SEVERAL RESEARCHES have been done to quantify malaria parasites seen in different blood samples collected from pregnant women by comparing blood samples from the placenta and peripheral blood samples taken from the hand.
The result of one of them showed that majority of the malaria parasites were found among red blood cells that were bound to the placenta’s CSA receptor, while only a minority of such malaria infected red cells (up to 25%) were seen to be attached to the CD36 receptors within the peripheral circulation.
Another study among some pregnant Cameroun women found that “P. falciparum infection was detected in 5.6%, 25.5% and 60.5% of the cases in peripheral blood, placental blood and placental histological sections respectively. Placental histology examination test was more sensitive (97.4%) than placental blood film (41.5%) and peripheral blood (8.0%) microscopy.”
These results help make sense of the statistical fact that many pregnant women infected with malaria may not show clinical signs. It also buttresses the absolute need for compliance with at least two curative doses of Intermittent Prevention Therapy (IPTp) Anti-Malaria drugs given during routine ante-natal clinic visits.