Today, the World Health Organization (WHO) released its 2022 World Malaria Report, an annual report that provides a comprehensive update on global and regional malaria data and trends. The report tracks investments in malaria programs and research; provides data on malaria prevention, diagnosis, treatment, and surveillance; and addresses a multitude of threats that could derail progress towards eradication.
Here’s what you need to know:
HOLDING THE LINE
Facing continued COVID-19 disruptions and a host of other challenges, the heroic efforts of national malaria programs, health workers, and partners helped prevent further setbacks in 2021. Nevertheless, the reality remains that progress has slowed in the fight against malaria. Global malaria cases increased for the second consecutive year, albeit at a slower pace than in 2020. The good news is that malaria deaths decreased slightly from 2020, a potential sign of successful malaria case management.
- There were an estimated 619,000 deaths due to malaria in 2021 – 6,000 (1%) fewer than in 2020 but still 51,000 (9%) higher than in 2019 before the pandemic struck.
- Malaria cases continued to rise in 2021, albeit at a slower pace than in 2020. There were an estimated 247 million cases in 2021, compared to 245 million in 2020 and 232 million in 2019.
- A large portion of these additional malaria deaths and cases were caused by COVID-related disruptions, which constrained access to critical malaria interventions. During the two peak pandemic years (2020/2021), these disruptions led to an additional 63,000 malaria deaths and 13 million cases.
- Thanks to global efforts to fight malaria, an estimated 185 million cases and 997,000 deaths were averted in 2021, bringing the total to 2 billion cases and 11.7 million deaths averted since 2000. These figures compare actuals to estimated malaria burden if rates remained at 2000 levels.
Regions and populations most at-risk
- Sub-Saharan Africa (SSA) carries the heaviest malaria burden, with an estimated 234 million cases (95%) and 593,000 deaths (96%) in 2021. The top 16 most malaria-affected countries, by cases, are all in SSA.
- Nigeria alone carries 26.6% and 31.3% of all malaria cases and deaths globally.
- Malaria deaths in SSA (an estimated 593,000) declined slightly from 2020 (599,000).
- Young children, particularly African children with limited access to healthcare, are disproportionately at-risk of malaria: 76% (~470,000) of all malaria deaths in 2021 were children under the age of 5. A child dies nearly every minute from this disease.
- Pregnant women are also at heightened risk: In 2021, there were an estimated 40 million pregnancies across 38 malaria-endemic African countries, of which 13.3 million (32%) were exposed to malaria infection during pregnancy.
- Displaced populations also face a high malaria risk. In 2021, Africa had record number of refugees and internally displaced people (34 million), per Internal Displacement Monitoring Centre.
Countries close to elimination
- In 2021, the number of countries that reported fewer than 10 indigenous cases increased from 23 in 2020 to 25 in 2021.
- In 2021, El Salvador and China were certified malaria-free by the WHO; and Belize, Cabo Verde, the Islamic Republic of Iran, and Malaysia maintained zero indigenous cases for the third consecutive year.
- Three subregions – Latin America, the Caribbean, and the Greater Mekong – have made significant progress towards regional elimination this century. But regional malaria hotspots in Venezuela, Haiti, and Myanmar, caused by political instability and other factors, have jeopardized those regional elimination efforts.
DELIVERING A FULL COMPLEMENT OF MALARIA TOOLS
Thanks to strong national commitments and global partnerships, distributions of insecticide-treated bed nets, rapid diagnostic tests, anti-malarial treatments, and other core malaria interventions largely maintained similar levels to the pre-pandemic year of 2019, despite continued COVID-19 disruptions. Furthermore, 2021 saw the continued scale-up of emerging interventions – including Seasonal Malaria Chemoprevention (SMC), Intermittent Preventive Treatment in Pregnancy (IPTp), and the RTS,S malaria vaccine – that protected millions of young children and pregnant women from malaria.
- In 2021, distributions of insecticide-treated bed nets maintained similar levels to the pre-pandemic year of 2019. Of the 171 million insecticide-treated bed nets planned for distribution in 2021, 128 million (75%) were ultimately delivered, with the remainder earmarked for 2023.
- By 2021, 68% of households in sub-Saharan Africa had at least one ITN, an increase from about 5% in 2000.
- In 2021, 53 countries implemented indoor residual spraying (IRS) campaigns to prevent malaria. While IRS is widely considered to be highly effective, the relatively high cost continues to constrain its scalability: overall, only 2.4% of the global population at-risk of malaria is protected by IRS.
- The use of Intermittent Preventive Treatment in Pregnancy (IPTp) has increased dramatically over the past decade. 35 African countries have adopted national IPTp programs to reduce the burden of malaria during pregnancy.
- In these 35 countries, 35% of pregnant women in sub-Saharan Africa received a full three-dose regimen of IPTp in 2021. This is more than double the rate of 2015, but slightly less than the pre-pandemic year of 2019.
- The average number of children treated per cycle of Seasonal Malaria Chemoprevention (SMC) steadily increased from about 200,000 in 2012 to almost 45 million in 2021. In 2021, there were an additional 11.6 million children treated with SMC per cycle. Nigeria contributed to 92% of this increase.
- In 2021, approximately 364,000 children received at least 1 dose of the RTS,S malaria vaccine through pilot introductions in Ghana, Kenya and Malaria. At least 27 countries in Africa have expressed interest in adopting the malaria vaccine as part of their national malaria control strategies.
Treatment & Diagnosis
- In 2021, countries distributed 223 million rapid diagnostic tests (RDTs) and 242 million courses of Artemisinin-based Combination Therapy (ACT), the world’s most widely used anti-malarial treatment. These figures are similar to levels reported before the pandemic.
- Treatment-seeking rates in malaria-endemic countries remain too low. According to household surveys conducted in sub-Saharan Africa, only 66.5% sought treatment for their most recent fever between 2015-2021, compared to 64.8% between 2005-2011.
- However, for those who do seek care, the use of diagnostic tests and ACT’s has grown considerably: from 29.8% and 14.3% between 2005-2011 to 56.5% and 23.9% between 2015-2021.
A CONVERGENCE OF THREATS
COVID-19 disruptions, humanitarian crises, natural disasters, insecticide and drug resistance, biological threats, and other challenges are testing the resilience of malaria programs around the world and threatening long-term progress towards eradication. These challenges have been further compounded by significant funding limitations for malaria research, development, and implementation, coupled with rising costs.
- In 2021, total funding to fight malaria was estimated at $3.5 billion, a slight increase from 2020. However, investments in 2021 were well below the estimated $7.3 billion needed to stay on track towards eradication.
- Factors that are driving up costs – i.e. global inflation, supply chain challenges related to COVID-19, and the war in Ukraine – are making it even more challenging for malaria programs to fund commodities and services.
- An estimated 268 million people in 37 malaria-endemic countries needed assistance due to health and humanitarian emergencies, not including the COVID-19 pandemic.
- In each of these countries, malaria increases occurred above what could be attributed to the COVID-19 pandemic alone.
- Conflicts, famine and flooding were the major contributors to these humanitarian emergencies, sometimes compounded by disease outbreaks.
- Widespread mosquito resistance to pyrethroids, the most commonly-used insecticide for insecticide-treated bed nets (ITNs), poses a major threat to malaria control programs that still rely heavily on pyrethroid-treated ITNs.
- Globally, mosquito resistance to pyrethroids has been detected in 87% of malaria-endemic countries in which resistance monitoring is taking place.
- The spread of Anopheles stephensi, an urban-adapted mosquito species, is posing an added challenge to disease control efforts in Africa – particularly in the Horn of Africa. This species transmits both of the malaria species that pose the greatest threat to public health — P. falciparum and P. vivax — and is resistant to many of the insecticides used in public health. If uncontrolled, its spread may increase the risk of malaria transmission in African cities.
Anti-malarial drug resistance
- Emerging resistance to artemisinin-based combination therapy (ACT), the mainstay for malaria treatment in most malaria-endemic settings, has been detected in Eritrea, Rwanda, Uganda, and in parts of the Greater Mekong subregion.
- Given the heavy reliance on ACTs in sub-Saharan Africa, even modest increases in ACT resistance can have serious, far-reaching consequences.
A PROMISING PIPELINE OF NEW MALARIA TOOLS AND STRATEGIES
Investments in the malaria research-and-development (R&D) pipeline have played a vital role in the dramatic reductions in malaria cases and deaths the last two decades. The development and massive roll-out of insecticide-treated bed nets (ITNs), anti-malarial drugs, and rapid diagnostic tests (RDTs) have saved millions of lives; but continued innovation is needed as new threats emerge in the fight against this disease. Despite insufficient funding, research institutions and private-sector partners are developing dozens of new prevention, diagnostic, treatment, and surveillance tools that combat these emerging threats and will help accelerate progress towards eradication.
New malaria prevention and vector control tools
- The use of pyrethroid and piperonyl butoxide (PBO) nets, which are more effective against pyrethroid-resistant mosquitoes than traditional ITN’s, doubled in 2021: 44% of the 220 million ITNs delivered were PBO nets (more than double the deliveries in 2020) – with plans for further scale-up.
- In addition, 2021 saw the continued scale-up (albeit at a smaller scale) of new dual-active ingredient ITNs and indoor residual sprays, which are optimally effective against pyrethroid-resistant mosquitoes but are currently more costly than existing options.
- Researchers are developing and scaling up 28 new vector control interventions, including spatial repellents, targeted baits that attract mosquitoes, lethal house lures (eaves tubes), and genetic engineering of mosquitoes.
- Following the first-ever WHO approval of a malaria vaccine – RTS,S – there are numerous malaria vaccines in development. The most advanced of these candidates is R21, which was 80% effective at preventing malaria in its Phase 3 clinical trials.
New malaria diagnostic and treatment tools
- The malaria diagnostic test market is dominated by RDTs that detect the HRP2 antigen expressed by the P. falciparum malaria parasite. However, the spread of malaria parasites with HRP2 gene deletions presents a major threat to reliable diagnosis. Thus, among the numerous RDTs in development are tests that better detect non-HRP2 malaria parasites.
- A wide range of next-generation anti-malarial treatments are being developed, including improvements to existing ACT drugs, drugs that combat ACT resistance, and drugs with lower-dosing regimens.
HOW YOU CAN HELP
Here are a few ways you can take action to help get the world back on track towards ending malaria in our lifetimes.
WHO World Malaria Report 2022
Global messaging from the World Malaria Report
WHO World Malaria Report 2022 press release
RBM Partnership to End Malaria’s World Malaria Report toolkit
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