As we gear up to celebrate World Malaria Day tomorrow, it is important to remember the impact of malaria in pregnancy. Each year across the globe, there are 125 million pregnant women who live in malaria endemic areas. Why is this important? Pregnant women have up to a 50% greater risk of malaria infection than women who are not pregnant. Each year in Africa alone, malaria in pregnancy kills 10,000 women, 75,000-200,000 infants and 100,000 newborns – making up 11% of all neonatal deaths.
This week I spoke with Dr. Clara Menéndez—a true pioneer in eliminating malaria in pregnancy—to reflect on where we’ve been and where we must go as a global maternal health community to protect women and their children from the unnecessary burden caused by malaria.
Malaria in pregnancy is such an important integration of two global health fields. How did you get started in this work?
CM: I started working on [malaria in pregnancy] many years ago as a young clinical epidemiologist. I spent many years in The Gambia in West Africa and basically I did what my boss told me to do, which was observing what the main problems in terms of health were for pregnant women in the area. One of the problems that struck me a lot was precisely malaria, which I knew at that time little to close to nothing [about]. I was going to maternal health meetings and learning how malaria prevention was a maternal health problem and an infant health problem so I started working in seeing why pregnant women were more susceptible to malaria, and so the question is the why but also how to reduce the burden.
What I’ve been working on a lot in the last 20 years is doing clinical research to see which intervention works better compared to another, how we can improve the antimalarials we’re using and what are the problems in getting those antimalarials to women. Then you move to questions of operational research. Once you know you have the tools, but women have no access to those tools, it’s not only a question of improving the tools, but improving the access. So at the end of the day I do a little bit of everything.
What an opportune time to be in The Gambia! You mentioned that one of the questions you asked as a young researcher was why pregnant women were more susceptible to malaria. Can you answer that question for us now?
CM: This is a very important question for which we don’t have a definite answer. The main one is that when the woman is pregnant, the immunological changes [her body goes through] to maintain the pregnancy have a large impact on many diseases, like infections, which make the woman more vulnerable. Also, the placenta offers a very good environment for the parasites to sequester and develop. These parasites really have a preference for being in the placenta. It’s also hypothesized that hormonal changes in pregnancy may also make the woman more susceptible.
Wow, it’s so interesting how the biology of pregnancy can make a woman more susceptible to malaria. What are the risks she faces if she does contract malaria? For her baby?
CM: For the mother it depends on the level of immunity that she has. If a woman is exposed to malaria for the first time in pregnancy, compared to if she had been exposed [to malaria] as a girl, then the manifestation with the disease is worse for both her and the fetus, potentially resulting in cerebral malaria, miscarriage, stillbirth or maternal death. There is a lot of range in consequences. In general, and especially for women who live in Africa, most of them are infected resulting in anemia, fever, malaise, flu-like symptoms and the woman is mostly fine. But if the woman is co-infected with HIV, which is very common in Africa, then things can get much worse and she can have severe disease. For the baby in general, if the woman has good immunity, the most frequent effect on her fetus is low birth weight for baby, and also sometimes prematurity, which is a bad thing for infant mortality. So for the baby, there are many indirect consequences. Congenital infection occurs, but it’s less common.
It sounds like malaria can have a tremendous effect on the health and life of both the mother and her fetus. On this World Malaria Day, what can you share about advancements in malaria prevention, diagnosis or treatment?
CM: For malaria in general, we have more drugs than ever before, more diagnostic tests and tools for prevention. But, for malaria in pregnancy the news is not great and that is one thing that was mentioned last Friday in New York when the Roll Back Malaria Partnership launched the Global Call to Action to Increase National Coverage of Intermittent Preventive Treatment of Malaria in Pregnancy at UNICEF, which the Maternal Health Task Force helped with. Intermittent preventive treatment of malaria in pregnancy, or IPTp, is a very cost-effective drug regimen of three or more doses of sulfadoxine-pyrimethamine (SP), an antimalarial, given during antenatal care visits to prevent infection. The bad news is the coverage of this strategy is very low and we haven’t made significant advances in [coverage in] many years.
In terms of diagnosis, we are not doing very well because [current] diagnostic tests are not very sensitive for detecting infection in the placenta and the new tests that are coming out are not tackling this issue very well.
In relation to treatment, we can say we have gained from the drugs that have been developed for everyone. So there are better drugs in terms of efficacy, and therefore they can be used in pregnant women with clinical malaria who are especially sick. However, the drugs are not necessarily safer than the ones we had before and there are concerns over these drugs because of possible teratogenic effects. So overall we are not doing great.
What will it take to address the ubiquitous problem of malaria in pregnancy and what are the biggest remaining challenges in this effort?
CM: The first thing we need to do is recognize that it is a priority health problem for maternal health and infant health. That should immediately have a reaction resulting in more funds targeted to reduce malaria in pregnancy. More funding would help us design better strategies to improve access for women to these interventions. But the first thing is to really accept that it is a priority health problem for maternal health. If we could control or prevent this infection in the endemic areas, we would improve the health of the women and the babies.
The challenges are many, but the main one now is understanding the reasons why women don’t get access to antimalarials. Sure, maybe we could improve efficacy of the drugs, but the main challenge is getting them to pregnant women. Also, another challenge is convincing the pharma industry to develop drugs that are safe for pregnancy so that a woman can take them without risking her pregnancy.
We have a lot of work left to do! Is there any good news you can share with us?
CM: One of the latest positive things are the updated IPTp recommendations. They are a clear example of progress and so I think we are going in a good direction. Now the challenge is to make it happen, that the women actually take the recommended three or more doses, instead of two doses. But the updated guidelines are a clear sign that policy makers are interested and are making a little progress.
The recognition of P. vivax—a less-studied strain of malaria—is another sign of progress in the field. In fact, there are more people in the world exposed to P. vivax than P. falciparum—the most commonly studied strain—but not all are infected who are exposed, and that’s why P. falciparum gets more attention. The transmission of P. vivax is low, but it’s important that we have recognized that P. vivax is there and that if we want to eliminate malaria as a health problem, especially for pregnant women, you have to tackle both P. vivax and P. falciparum.
What is your greatest hope for advancement in the field over the next several years?
CM: My greatest hope is that all women who are exposed to malaria have access to the full spectrum of the strategies that are available: that there is no single woman who does not have access to insecticide-treated bed nets, IPTp and other strategies for prevention. There is no reason why they should not have this access. So I think the advancement in the field is not a basic one, it’s a purely operational one. If we understand why [access] is not happening, we need to understand soon why and react quickly to resolve it. We need to be more alert, but also more effective, in taking things to the people who are vulnerable, and the most vulnerable people are pregnant women. Right now the average IPTp coverage in Africa is less than 25%, but my greatest hope for the next several years is that the coverage is 85% or 100%, because there is no reason why it should not be like that.
Additional resources:
- Global Call to Action to Increase National Coverage of Intermittent Preventive Treatment of Malaria in Pregnancy
- WHO policy brief for the implementation of intermittent preventive treatment of malaria in pregnancy using sulfadoxine-pyrimethamine (IPTp-SP)
- Roll Back Malaria Progress & Impact Series: The contribution of malaria control to maternal and newborn health
- Interview with Dr. Matthew Chico of the London School of Tropical Medicine and Hygiene, for the programme ‘Africa Digest’. The focus of this interview was on the importance of preventive measures for malaria in pregnancy.
- Video from UNICEF event on scaling up interventions against malaria during pregnancy
- UNICEF’s Malaria in pregnancy infographic