Malaria in Pregnancy Bill Brieger | 16 Jan 2010 07:47 am
Malaria in pregnancy as we move toward elimination
Over the past decade countries in stable falciparum malaria transmission areas adopted the use of intermittent preventive treatment of malaria in pregnancy (IPTp) using the drug sulfadoxine-pyrimethamine (SP). At present only two of these locations are pulling back or considering stopping IPTp.
Both Rwanda and Zanzibar in the United Republic of Tanzania may no longer need IPTp because successful malaria control interventions have brought transmission down. Rwanda specifically stopped using IPTp, while Zanzibar is still considering the implications of changing policy until more evidence is available.
Currently in areas of unstable, seasonal or epidemic malaria where it is unlikely that adults would have developed partial immunity and carry asymptomatic disease, IPTp has not generally been used. Instead prompt laboratory diagnosis (including RDTs) and appropriate treatment have been recommended for addressing malaria in pregnancy.
Just because the transmission picture changes as we successfully move toward sustained control and pre-elimination, does not mean pregnant women are not at risk of malaria. In fact as high transmission areas begin begin to resemble the unstable transmission zones, all people will be at greater risk of severe malaria.
Recent articles show that this risk to pregnant women extends to their offspring. Aribodor and colleagues in Nigeria documented again that not only does placental malaria result in significantly lower birth weight than that of children born to mothers without infection, but that low birth weight (LBW), defined as less than 2,500 g, was more common among those born to mothers with placental malaria. Low birth weight is an important risk factor in neonatal and infant mortality.
Walther et al. looked beyond the actual birth of the child and found that regardless of whether the child was born with LBW, the fact that the mother had placental malaria had a “negative impact on the infant’s subsequent weight development that is independent of LBW, suggesting that the longer term effects of PM have been underestimated, even in areas where malaria transmission is declining.”
The question arises as we move toward lower transmission and elimination, but not immediately toward lower risk – what can we do to protect pregnant women in addition to providing them bednets?
Daniel Chandramohan at the 11th meeting of RBM’s Malaria in Pregnancy Working Group suggested Intermittent Screening and Treatment (IST) as an appropriate strategy which might consist of:
- Screening for malaria (RDT or Microscopy) at first ANC visit
- Treatment with a long acting antimalarial combination (e.g. DHA+PPQ, SP+AQ, SP+AZ, SP+MQ)
- Further screening and treatment at 2nd and 3rd trimester (2 to 3 IST per pregnancy) plus passive case management
Lucy Smith and co-researchers found that pregnant women liked “both intermittent screening and treatment and intermittent preventive treatment appeared equally acceptable to pregnant women as strategies for the control of malaria in pregnancy,” valuing the addition of such services to routine Antenatal Care.
Finding appropriate ways of protecting pregnant women from malaria, as we move toward elimination, must remain a priority in all endemic countries.