More pregnant women and children protected from malaria, but accelerated efforts and funding needed to reinvigorate global response, WHO report shows
The World malaria report 2019 provides a comprehensive update on global and regional malaria data and trends. The report tracks investments in malaria programmes and research as well as progress across all intervention areas: prevention, diagnosis, treatment, elimination and surveillance. It also includes dedicated chapters on the consequences of malaria on maternal, infant and child health, the “High Burden to High Impact” approach as well as biological threats to the fight against malaria.
The 2019 report is based on information received from more than 80 countries and areas with ongoing malaria transmission. This information is supplemented by data from national household surveys and databases held by other organizations.
This year’s report at a glance
Regional and global trends in burden of malaria cases and deaths
- In 2018, an estimated 228 million cases of malaria occurred worldwide (95% confidence interval [CI]: 206–258 million), compared with 251 million cases in 2010 (95% CI: 231–278 million) and 231 million cases in 2017 (95% CI: 211–259 million).
- Most malaria cases in 2018 were in the World Health Organization (WHO) African Region (213 million or 93%), followed by the WHO South-East Asia Region with 3.4% of the cases and the WHO Eastern Mediterranean Region with 2.1%.
- Nineteen countries in sub-Saharan Africa and India carried almost 85% of the global malaria burden. Six countries accounted for more than half of all malaria cases worldwide: Nigeria (25%), the Democratic Republic of the Congo (12%), Uganda (5%), and Côte d’Ivoire, Mozambique and Niger (4% each).
- The incidence rate of malaria declined globally between 2010 and 2018, from 71 to 57 cases per 1000 population at risk. However, from 2014 to 2018, the rate of change slowed dramatically, reducing to 57 in 2014 and remaining at similar levels through to 2018.
- The WHO South-East Asia Region continued to see its incidence rate fall – from 17 cases of the disease per 1000 population at risk in 2010 to five cases in 2018 (a 70% decrease). In the WHO African Region, case incidence levels also declined from 294 in 2010 to 229 in 2018, representing a 22% reduction. All other WHO regions recorded either little progress or an increase in incidence rate. The WHO Region of the Americas recorded a rise, largely due to increases in malaria transmission in the Bolivarian Republic of Venezuela.
- Between 2015 and 2018, only 31 countries, where malaria is still endemic, reduced case incidence significantly and were on track to reduce incidence by 40% or more by 2020. Without accelerated change, the Global technical strategy for malaria 2016–2030 (GTS) milestones for morbidity in 2025 and 2030 will not be achieved.
- Plasmodium falciparum is the most prevalent malaria parasite in the WHO African Region, accounting for 99.7% of estimated malaria cases in 2018, as well as in the WHO South-East Asia Region (50%), the WHO Eastern Mediterranean Region (71%) and the WHO Western Pacific Region (65%).
- Globally, 53% of the P. vivax burden is in the WHO South-East Asia Region, with the majority being in India (47%). P. vivax is the predominant parasite in the WHO Region of the Americas, representing 75% of malaria cases.
- In 2018, there were an estimated 405 000 deaths from malaria globally, compared with 416 000 estimated deaths in 2017, and 585 000 in 2010.
- Children aged under 5 years are the most vulnerable group affected by malaria. In 2018, they accounted for 67% (272 000) of all malaria deaths worldwide.
- The WHO African Region accounted for 94% of all malaria deaths in 2018. Although this region was home to the highest number of malaria deaths in 2018, it also accounted for 85% of the 180 000 fewer global malaria deaths reported in 2018 compared with 2010.
- Nearly 85% of global malaria deaths in 2018 were concentrated in 20 countries in the WHO African Region and India; Nigeria accounted for almost 24% of all global malaria deaths, followed by the Democratic Republic of the Congo (11%), the United Republic of Tanzania (5%), and Angola, Mozambique and Niger (4% each).
- In 2018, only the WHO African Region and the WHO South-East Asia Region showed reductions in malaria deaths compared with 2010. The WHO African Region had the largest absolute reduction in malaria deaths, from 533 000 in 2010 to 380 000 in 2018. Despite these gains, the malaria mortality reduction rate has also slowed since 2016.
Maternal, infant and child health consequences of malaria
- In 2018, about 11 million pregnancies in moderate and high transmission sub-Saharan African countries would have been exposed to malaria infection.
- In 2018, prevalence of exposure to malaria infection in pregnancy was highest in the West African subregion and Central Africa (each with 35%), followed by East and Southern Africa (20%). About 39% of these were in the Democratic Republic of the Congo and Nigeria.
- The 11 million pregnant women exposed to malaria infections in 2019 delivered about 872 000 children with low birthweight (16% of all children with low birthweight in these countries), with West Africa having the highest prevalence of low birthweight children due to malaria in pregnancy.
- Between 2015 and 2018 in 21 moderate to high malaria burden countries in the WHO African Region, the prevalence of anaemia in children under 5 years with a positive rapid diagnostic test (RDT) was double that of children with a negative RDT. In the children who were positive for malaria, 9% had severe anaemia and 54% had moderate anaemia; in contrast, in the children without malaria, only 1% had severe anaemia and 31% had moderate anaemia.
- The countries with the highest percentage of severe anaemia among children aged under 5 years who were positive for malaria were Senegal (26%), Mali (16%), Guinea (14%) and Mozambique (12%). For most other countries, severe anaemia ranged from 5% to 10%.
- Overall, about 24 million children were estimated to be infected with P. falciparum in 2018 in sub-Saharan Africa, and an estimated 1.8 million of them were likely to have severe anaemia.
High burden to high impact approach
- There were about 155 million malaria cases in the 11 high burden to high impact (HBHI) countries in 2018, compared with 177 million in 2010. The Democratic Republic of the Congo and Nigeria accounted for 84 million (54%) of total cases.
- Of the 10 highest burden countries in Africa, Ghana and Nigeria reported the highest absolute increases in cases of malaria in 2018 compared with 2017. The burden in 2018 was similar to that of 2017 in all other countries, apart from in Uganda and India, where there were reported reductions of 1.5 and 2.6 million malaria cases, respectively, in 2018 compared with 2017.
- Malaria deaths reduced from about 400 000 in 2010 to about 260 000 in 2018, the largest reduction being in Nigeria, from almost 153 000 deaths in 2010 to about 95 000 deaths in 2018.
- By 2018, in all of the 11 HBHI countries, at least 40% of the population at risk were sleeping under long-lasting insecticidal nets (LLINs), the highest percentage being in Uganda (80%) and the lowest in Nigeria (40%).
- Only Burkina Faso and the United Republic of Tanzania were estimated as having more than half of pregnant women receiving three doses of intermittent preventive treatment in pregnancy (IPTp3) in 2018. In Cameroon, Nigeria and Uganda, the estimated coverage was about 30% or less.
- Six countries in Africa’s Sahel subregion implemented seasonal malaria chemoprevention (SMC) in 2018; a mean total of 17 million children, out of the 26 million targeted, were treated per SMC cycle.
- The percentage of children aged under 5 years with fever seeking treatment varied from 58% in Mali to 82% in Uganda. In the Democratic Republic of the Congo and Mali, more than 40% of children were not brought for care at all. Testing was also worryingly low in children who were brought for care, with 30% or less being tested in Cameroon, the Democratic Republic of the Congo and Nigeria.
- Except for India, direct domestic investment remains very low relative to international funding in the HBHI countries.
Malaria elimination and prevention of re‑establishment
- Globally, the elimination net is widening, with more countries moving towards zero indigenous cases: in 2018, 49 countries reported fewer than 10 000 such cases, up from 46 countries in 2017 and 40 countries in 2010. The number of countries with fewer than 100 indigenous cases – a strong indicator that elimination is within reach – increased from 17 countries in 2010, to 25 countries in 2017 and 27 countries in 2018.
- Paraguay and Uzbekistan were awarded WHO certification of elimination in 2018, with Algeria and Argentina achieving certification in early 2019. In 2018, China, El Salvador, Iran, Malaysia and Timor-Leste reported zero indigenous cases.
- One of the key GTS milestones for 2020 is elimination of malaria in at least 10 countries that were malaria endemic in 2015. At the current rate of progress, it is likely that this milestone will be reached.
- In 2016, WHO identified 21 countries with the potential to eliminate malaria by the year 2020. WHO is working with the governments in these countries – known as “E-2020 countries” – to support their elimination acceleration goals.
- Although 10 E-2020 countries remain on track to achieve their elimination goals, Comoros and Costa Rica reported increases in indigenous malaria cases in 2018 compared with 2017.
- In the six countries of the Greater Mekong subregion (GMS) – Cambodia, China (Yunnan Province), Lao People’s Democratic Republic, Myanmar, Thailand and Viet Nam – the reported number of malaria cases fell by 76% between 2010 and 2018, and malaria deaths fell by 95% over the same period. In 2018, Cambodia reported no malaria related deaths for the first time in the country’s history.
Investments in malaria programmes and research
- In 2018, an estimated US$ 2.7 billion was invested in malaria control and elimination efforts globally by governments of malaria endemic countries and international partners – a reduction from the US$ 3.2 billion that was invested in 2017. The amount invested in 2018 fell short of the US$ 5.0 billion estimated to be required globally to stay on track towards the GTS milestones.
- Nearly three quarters of investments in 2018 were spent in the WHO African Region, followed by the WHO Region of the Americas (7%), the WHO South-East Asia Region (6%), and the WHO Eastern Mediterranean Region and the WHO Western Pacific Region (5% each).
- In 2018, 47% of total funding for malaria was invested in low-income countries, 43% in lower- middle-income countries and 11% in upper-middle-income countries. International funding represented the major source of funding in low-income and lower-middle-income countries, at 85% and 61%, respectively. Domestic funding has remained stable since 2010.
- Of the US$ 2.7 billion invested in 2018, US$ 1.8 billion came from international funders. Governments of malaria endemic countries contributed 30% of total funding (US$ 900 million) in 2018, a figure unchanged from 2017. Two thirds of domestically sourced funds were invested in malaria control activities carried out by national malaria programmes (NMPs), with the remaining share estimated as the cost of patient care.
- As in previous years, the United States of America (USA) was the largest international source of malaria financing, providing US$ 1.0 billion (37%) in 2018. Country members of the Development Assistance Committee together accounted for US$ 300 million (11%). The United Kingdom of Great Britain and Northern Ireland contributed around US$ 200 million (7%).
- Of the US$ 2.7 billion invested in 2018, US$ 1.0 billion was channelled through the Global Fund to Fight AIDS, Tuberculosis and Malaria.
- Although funding for malaria has remained relatively stable since 2010, the level of investment in 2018 is far from what is required to reach the first two milestones of the GTS; that is, a reduction of at least 40% in malaria case incidence and mortality rates globally by 2020, compared with 2015 levels.
- US$ 663 million was invested in basic research and product development for malaria in 2018, an increase of US$ 18 million compared with 2017.
- Funding for drug research and development (R&D) increased to the highest level ever recorded, from US$ 228 million in 2017 to US$ 252 million in 2018. This increase was a result of private sector industry investment in several Phase II trials of new chemical entities with the potential for single- exposure radical cure.
Deliveries of malaria commodities
Insecticide-treated mosquito nets
- Between 2016 and 2018, a total of 578 million insecticide-treated mosquito nets (ITNs), mainly LLINs, were reported by manufacturers as having been delivered globally, with 50% going to Côte d’Ivoire, the Democratic Republic of the Congo, Ethiopia, Ghana, India, Nigeria, Uganda and the United Republic of Tanzania.
- In 2018 about 197 million ITNs were delivered by manufacturers, of which more than 87% were delivered to countries in sub-Saharan Africa.
- Globally, 80% of ITNs were distributed through mass distribution campaigns, 10% in antenatal care facilities and 6% as part of immunization programmes.
Rapid diagnostic tests
- An estimated 412 million RDTs were sold globally in 2018.
- In 2018, 259 million RDTs were distributed by NMPs. Most RDTs (64%) were tests that detected P. falciparum only and were supplied to sub-Saharan Africa.
Artemisinin-based combination therapy
- An estimated 3 billion treatment courses of artemisinin-based combination therapy (ACT) were procured by countries over the period 2010–2018. An estimated 63% of these procurements were reported to have been made for the public sector.
- In 2018, 214 million ACT treatment courses were delivered by NMPs, of which 98% were in the WHO African Region.
- Half of people at risk of malaria in sub-Saharan Africa are sleeping under an ITN; in 2018, 50% of the population were protected by this intervention, an increase from 29% in 2010. Furthermore, the percentage of the population with access to an ITN increased from 33% in 2010 to 57% in 2018. However, coverage has improved only marginally since 2015 and has been at a standstill since 2016.
- Households with at least one ITN for every two people increased to 72% in 2018, from 47% in 2010. However, this figure represents only a modest increase over the past 3 years, and remains far from the target of universal coverage.
- Fewer people at risk of malaria are being protected by indoor residual spraying (IRS), a prevention method that involves spraying the inside walls of dwellings with insecticides. Globally, IRS protection declined from a peak of 5% in 2010 to 3% in 2018, with declining trends seen across all WHO regions apart from the WHO Eastern Mediterranean Region and the WHO African Region where IRS protection increased between 2016 and 2018.
- Although IRS coverage dropped from 180 million people at risk protected globally in 2010 to 130 million in 2018, the 2018 figure was an increase of 15 million compared with 2017.
- The declines in IRS coverage may be due to the switch from pyrethroids to more expensive insecticides in response to increasing pyrethroid resistance, or changes in operational strategies (e.g. at-risk populations decreasing in countries aiming for elimination of malaria).
- To protect women in areas of moderate and high malaria transmission in Africa, WHO recommends IPTp with the antimalarial drug sulfadoxine-pyrimethamine (SP). Among 36 African countries that reported on IPTp coverage levels in 2018, an estimated 31% of eligible pregnant women received the recommended three or more doses of IPTp, compared with 22% in 2017 and 2% in 2010, indicating considerable improvements in country uptake.
- About 18% of women who use antenatal care services at least once do not receive any IPTp, representing a missed opportunity that, if harnessed, could considerably and rapidly improve IPTp coverage.
- In 2018, 31 million children in 12 countries in Africa’s Sahel subregion were protected through SMC programmes. All targeted children received treatment in Cameroon, Guinea, Guinea-Bissau, Mali and Senegal. However, about 12 million children who could have benefited from this intervention were not covered, mainly due to a lack of funding.
Diagnostic testing and treatment
- Prompt diagnosis and treatment is the most effective way to prevent a mild case of malaria from developing into severe disease and death. Based on national household surveys completed in 20 countries in sub-Saharan Africa between 2015 and 2018, a median of 42% (interquartile range [IQR]: 34–49%) of children with a fever (febrile) were taken to a trained medical provider for care in the public sector compared with 10% (IQR: 8–22%) in the formal private sector and 3% (IQR: 2–7%) in the informal private sector.
- A high proportion of febrile children did not receive any medical attention (median: 36%, IQR: 28–45%). Poor access to health care providers or lack of awareness of malaria symptoms among caregivers are among the contributing factors.
- The percentage of patients suspected of having malaria who are seen in public health facilities and tested with either an RDT or microscopy, rose from 36% in 2010 to 84% in 2018.
- In 71% of moderate to high transmission countries in sub-Saharan Africa, the percentage of suspected cases tested with any parasitological test was greater than 80% in 2018.
- According to 19 nationally representative household surveys conducted between 2015 and 2018 in sub-Saharan Africa, the median percentage of febrile children brought for care who received a finger or heel stick (suggesting that a malaria diagnostic test may have been performed) was greater in the public sector (median: 66%, IQR: 49–75%) than in the formal private sector (median: 40%, IQR: 16–46%) or the informal private sector (median: 9%, IQR: 5–22%).
- According to 61 surveys conducted in 29 sub-Saharan African countries between 2010 and 2018, the percentage of children with a fever that received a diagnostic test before antimalarial treatment in the public health sector increased from a median of 48% (IQR: 30–62%) in 2010–2013 to a median of 76% (IQR: 60–86%) in 2015–2018.
- Based on 20 household surveys conducted in sub-Saharan Africa in 2015–2018, the median percentage of febrile children who were treated with any antimalarial drug was higher in the public sector (median: 48%, IQR: 30–69%) than in the formal private sector (median: 40%, IQR: 21–51%) or the informal private sector (median: 18%, IQR: 10–29%).
- Data from 20 national surveys conducted in sub-Saharan Africa show that for the period 2015–2018, an estimated 47% (IQR: 29–69%) of febrile children brought for treatment for malaria in the public health sector received antimalarial drugs, compared with 59% (IQR: 53–84%) among those visiting a community health worker and 49% (IQR: 19–55%) in the formal medical private sector.
- Based on 19 surveys, antimalarial treatments among febrile children who received antimalarial medicine were slightly more likely to be ACTs if treatment was sought in the public sector (median: 80%, IQR: 45–94%) than in the formal private sector (median: 77%, IQR: 43–87%) or the informal private sector (median: 60%, IQR: 40–84%).
- To bridge the treatment gap among children, WHO recommends the uptake of integrated community case management (iCCM). This approach promotes integrated management of common life-threatening conditions in children – malaria, pneumonia and diarrhoea – at health facility and community levels. In 2018, 30 countries were implementing iCCM at different levels, with only a few implementing nationally.
Malaria surveillance systems
- Pillar 3 of the GTS is to transform malaria surveillance into a core intervention. To understand whether malaria surveillance systems are fit for purpose, WHO recommends the regular monitoring and evaluation of surveillance systems.
- The Global Malaria Programme (GMP), in collaboration with the University of Oslo, has developed standardized malaria modules in District Health Information Software2 (DHIS2) for aggregate and case-based collection of routine data with associated data elements, dashboards of key epidemiological and data quality indicators, reports and a curriculum for facility-level data analysis to facilitate data analysis and interpretation.
- As of October 2019, 23 countries have installed the WHO aggregate malaria module and another six installations are planned over the next year. Five countries have already developed and integrated their own malaria module into DHIS2.
- WHO has been working in coordination with national health management information systems (HMIS) departments of ministries of health, in particular the HBHI countries, to establish structured dynamic databases known as data repositories. The GMP has developed an easily adaptable repository structure in DHIS2, with guidance on relevant data elements and indicators, their definitions and computation to cover key thematic areas. So far, work to develop these databases has started in Gambia, Ghana, Mozambique, Nigeria, Uganda and the United Republic of Tanzania.
- WHO also encourages countries to implement surveillance system assessments. An example of such an assessment and its role in improving surveillance systems is illustrated through a case study of Mozambique.
Responding to biological threats to the fight against malaria
Pfhrp2/3 gene deletions
- Deletions in the pfhrp2 and pfhrp3 (pfhrp2/3) genes of the parasite renders parasites undetectable by RDTs based on histidine-rich protein 2 (HRP2). The prevalence of dual pfhrp2 and pfhrp3 among symptomatic patients reached as high as 80% in Eritrea and Peru.
- WHO has recommended that countries with reports of pfhrp2/3 deletions or neighbouring countries should conduct representative baseline surveys among suspected malaria cases to determine whether the prevalence of pfhrp2/3 deletions causing false negative RDT results has reached a threshold for RDT change (>5% pfhrp2 deletions causing false negative RDT results).
- WHO is tracking published reports of pfhrp2/3 deletions using the Malaria Threat Map mapping tool. To date, 28 countries have reported pfhrp2 deletions.
- PfKelch13 mutations have been identified as molecular markers of partial artemisinin resistance. PfKelch13 mutations associated with artemisinin resistance are widespread in the GMS, and have also been detected at a significant prevalence (over 5%) in Guyana, Papua New Guinea and Rwanda. In the case of Rwanda, the presence of PfKelch13 mutations does not affect efficacy of first-line treatment.
- In the WHO Western Pacific Region, artemisinin resistance has been confirmed in Cambodia, Lao People’s Democratic Republic and Viet Nam through several studies conducted between 2001 and 2018. Treatment efficacy for P. vivax remains high across all countries where treatment failure rates are below 10%.
- In the WHO African Region the efficacy rates of artemether-lumefantrine (AL), artesunate- amodiaquine (AS-AQ) and dihydroartemisinin-piperaquine (DHA-PPQ) for P. falciparum were more than 98%, and efficacy has remained high over time.
- Treatment efficacy with first-line treatment remains high for P. falciparum and P. vivax in the WHO Region of the Americas.
- In the WHO South-East Asia Region, the presence of molecular markers of artemisinin resistance has been reported in Bangladesh, India, Myanmar and Thailand. With the exception of Myanmar, failure rates of P. falciparum to first-line ACTs were found to be above 10% and were as high as 93% in Thailand. For P. vivax most countries continue to demonstrate high efficacy of chloroquine (CQ), except for Myanmar and Timor-Leste.
- In the WHO Eastern Mediterranean Region, high failure rates of treatment with artesunate- sulfadoxine-pyrimethamine (AS-SP) for P. falciparum in Somalia and Sudan led to a change in first-line treatment policy to AL. For P. vivax there is high treatment efficacy with AL and CQ in all countries where a therapeutic efficacy study (TES) has been conducted.
- From 2010 through 2018, some 81 countries reported data on insecticide resistance monitoring to WHO.
- Of the 81 malaria endemic countries that provided data for 2010–2018, resistance to at least one of the four insecticide classes in one malaria vector from one collection site was detected in 73 countries, an increase of five countries compared with the previous reporting period 2010–2017. In 26 countries, resistance was reported to all main insecticide classes.
- Resistance to pyrethroids – the only insecticide class currently used in ITNs – is widespread and was detected in at least one malaria vector in more than two thirds of the sites tested, and was highest in the WHO African Region and in the WHO Eastern Mediterranean Region.
- Resistance to organochlorines was detected for at least one malaria vector in almost two thirds of the sites. Resistance to carbamates and organophosphates was less prevalent and was detected in 31% and 26% of the tested sites, respectively. Prevalence was highest for carbamates in the WHO South-East Asia Region and for organophosphates in the WHO South-East Asia Region and in the WHO Western Pacific Region.
- All the standard insecticide resistance data reported to WHO are included in the WHO Global Insecticide Resistance database, and are available for exploration via the Malaria Threats Map. This online tool was extended in 2019 to cover invasive mosquito species, and currently shows the geographical extent of reports on the detection of Anopheles stephensi.
- To guide resistance management, countries should develop and implement a national plan for insecticide-resistance monitoring and management, drawing on the WHO Framework for a national plan for monitoring and management of insecticide resistance in malaria vector. In 2018, a total of 45 countries reported having completed plans for resistance monitoring and management and 36 were currently in the process of developing them.
- NMPs and their partners should consider the deployment of pyrethroid-piperonyl butoxide nets in geographical areas where the main malaria vectors meet the criteria recommended by WHO in 2017, rather than being based on whether the whole country meets the criteria.