Malaria takes a particularly heavy toll on pregnant women and young children.
Our analysis shows that, in 2018, an estimated 11 million pregnant women in sub-Saharan Africa were infected with malaria. This resulted in nearly 900 000 children born with a low birth weight. Globally, children account for nearly 70% of malaria-related deaths.
The report provides important insight – grounded in strong evidence – into what happens to a pregnant woman and her fetus when the mother is infected with malaria. For example, malaria infection during pregnancy can lead to anaemia in the mother, which can result in complications in pregnancy, premature birth and a low-birth-weight child. Children who are born preterm or with a low birth weight are at a very high risk of dying in their first few weeks of life.
Even when a healthy child is born, malaria infection in children can lead to severe malaria and, very often in the highest burden countries, severe malaria anaemia, which also puts the child at greater risk of death.
WHO recommends at least 3 doses of intermittent preventive treatment in pregnancy (IPTp) for all pregnant women living in malaria-endemic areas of sub-Saharan Africa. In recent years, coverage of the first 2 doses of IPTp has increased steadily, though not at a rapid rate. Notably, this year’s report shows a significant jump of about 10 percentage points in coverage of the third dose of IPTp between 2017 and 2018.
The reason is two-fold. The first is that as WHO receives more data from countries, we have been able to analyse the situation more accurately. And the second is that some countries have put significant effort into scaling up this intervention over the last couple of years. Burkina Faso, Tanzania and a few other countries, for example, have reached significant levels of coverage of the third IPTp dose.
Intermittent preventive treatment in pregnancy (IPTp) is delivered through antenatal care clinics (ANC). Whenever a pregnant woman seeks ANC services, she is supposed to receive a dose of IPTp after her first trimester, as long as the doses are administered at monthly intervals.
The reasons for barriers are two-fold. First, access to ANC coverage is variable: in some countries it’s very high while in others it’s moderate or even low. Often you will see reasonably high coverage of IPTp during the first visit to an ANC clinic, but lower IPT coverage as ANC visits taper off. As such, the biggest barrier to the scale-up of IPTp is insufficient ANC coverage and/or repeat ANC access.
The second barrier is linked to health worker practices and health systems issues. Our analysis shows that about 20% of women who are eligible for IPTp do not receive the drug when they visit an ANC clinic for the first time, either because the health worker does not prescribe it or the drug is not available.
A lot of malaria research is done to provide evidence either on the way we implement malaria interventions, or to allow us to better understand the epidemiology of the disease. Some of this operational and epidemiological research can feed into programmes and have immediate impact.
However, investment in the discovery and development of new tools usually takes a long time to bear fruit. Fortunately, there are some promising tools in the pipeline. The first vaccine against malaria, RTS,S, is now being evaluated through a pilot implementation programme. New types of insecticide-treated nets to fight malaria-carrying mosquitoes are also being introduced. Continued investment in the research and development of new tools will be critical to reaching our common goal of a world free of malaria.
WHO applies 3 methods for calculating estimates of malaria cases. One method uses routine data from countries without any adjustments; in other words, we use the data “as is”, directly from the country. This approach applies to countries that have a very low number of malaria cases, high-quality surveillance systems, and are near elimination.
The second method is for countries outside of sub-Saharan Africa, excluding Botswana, Ethiopia, Namibia and Rwanda, that have a good public health surveillance system but where a large proportion of patients seek care in the private sector or do not seek treatment at all. Here, adjustments for testing rates, reporting and treatment seeking rates are applied to the reported data.
The third method applies to most countries in the WHO African Region, where surveillance systems have been historically weak. To come up with a reliable estimate, we measure the relationship between parasite prevalence and case incidence within a specific area.
It’s a good question but one without an easy answer. We know that many patients seek care in the public sector. We also know what proportion of those patients are tested for malaria.
Although the evidence suggests that most of the patients who seek care for malaria end up receiving an effective artemisinin combination therapy, the actual quality of that treatment – for example, whether patients are given the right number of doses or whether they comply with the dosage regime – is difficult to determine from the data we currently have at our disposal. But we do know that the drugs available in nearly all malaria-endemic countries remain highly efficacious.
It’s important to note that, for young children in sub-Saharan Africa showing signs of a fever, access to health care remains far too low. According to country surveys conducted in recent years, 36% of febrile children in the region were not taken for care with a trained medical provider.
The vision of our global strategy is a malaria-free world. The targets are actually very ambitious: reductions of at least 90% in malaria morbidity and mortality, and the elimination of malaria in at least 35 countries between 2015 and 2030 – that’s an average of at least two countries becoming malaria-free each year. So it’s a highly ambitious strategy.
The reason why we don’t have a time-bound goal is that with the current tools and current levels of investment, it’s unlikely we will achieve global eradication by 2030. At the present time, we don’t have an evidence base to show that malaria can be eradicated by 2050 with existing tools, even if very high coverage levels of those tools are achieved in all malaria-endemic settings.
According to the recently released executive summary of the WHO Strategic Advisory Group on Malaria Eradication, a successful approach to malaria eradication calls for focused effort in four areas. One of the highest priorities is a renewed research and development agenda. Other priorities include access to affordable, people-centred health services; a reliable, rapid and accurate surveillance and response system; and the development of national and subnational strategies tailored to local conditions.
In the World malaria report 2017, the main message was that the fight against malaria was at a crossroads. The key message for 2018 was that it’s time to get back on track in the global response to the disease.
To get back on track, WHO and the RBM Partnership to End Malaria launched the “High burden to high impact” (HBHI) approach in 2018. The new approach essentially recognises the need for stepped-up action across all malaria-endemic countries, and particularly in the 11 countries carrying the highest burden of the disease. Together, these 11 countries account for nearly 70% of the global burden of malaria mortality and morbidity.
A number of countries have initiated the HBHI response and are rethinking their strategic planning, interventions and investment based on four response elements. These include galvanising political will to reduce the toll of malaria; better use of strategic information to drive impact; better policy guidance, policies and strategies; and improved coordination of the response within the country – between the ministry of health, the national malaria control programmes and local partners.So, quite clearly, enhanced effort, a smarter way of doing business and better use of the tools at our disposal, including the data, are the best ways to get back on track to meet the goals of our global strategy.
WHO works with all the malaria-endemic countries to monitor the levels of both drug and insecticide resistance. What we know, at the moment, is that while there is emerging resistance to some antimalarial drugs, particularly in the Greater Mekong Subregion, all current first-line drugs used by all malaria-endemic countries remain highly efficacious.
On insecticide resistance, we are seeing increasing levels of resistance to pyrethroids across all malaria-endemic countries. Current evidence suggests that nets treated with pyrethroid insecticides should continue to be used by communities to protect themselves against malaria. However, evidence has also shown that in many areas where mosquitoes have developed resistance to pyrethroids, another type of net treated with a pyrethroid and a synergist (known as a pyrethroid-PBO net) provides improved impact against malaria; the scale-up of such nets is warranted in these areas.
In terms of other threats, we are closely monitoring an emerging issue whereby malaria parasites have developed the capacity to evade detection by the most commonly-used rapid diagnostic tests. This is a problem with high prevalence in Eritrea, and we are reviewing data from several other countries in Africa. The immediate threat in moderate-to-high transmission African countries is low – diagnostic tests still remain highly sensitive – but we are looking at the situation closely.
The single biggest threat in the fight against malaria, of course, remains funding. While the global community has done an excellent job in ensuring that funding is maintained – the recent replenishment of the Global Fund to Fight AIDS, Tuberculosis and Malaria was the single largest replenishment in the Fund’s history, for example – we still see that financing levels for malaria remain relatively flat. Unless we do things better and smarter, we may only be able to sustain the gains already made. In some settings, even maintaining the gains will be a challenge amid massive population growth.
Interview with Dr Abdisalan Noor, Team Leader of the WHO Global Malaria Programme's Surveillance Unit and lead author of the World malaria report 2019