The three keys to Zambia's fight against malaria's comeback

For World Malaria Day, we examine how the country is successfully using a combination of empowered community health workers, mass drug administration, and data to combat a resurgence of the deadly disease

A Zambian boy sits inside a mosquito net to prevent malarial infection.
A Zambian boy sits inside a mosquito net to prevent malarial infection.

Ten years ago, malaria was making an unwelcome comeback in Zambia. After declining from nearly 400 cases per 1,000 residents in 2000 to less than half that level in 2010, suddenly malaria rates began inching back up.

“When malaria began its resurgence in 2010, the ministry of health and its partners realized they would never be successful trying to reach everyone with every intervention,” said Kafula Silumbe, Zambia team lead of PATH’s Malaria Control and Elimination Partnership in Africa. “They decided to transition to a more data-driven strategic approach.”

That more targeted approach, piloted from 2010 to 2012 and then rolled out nationally, relied on some key partners: more than 16,000 specially trained and equipped community health workers (CHWs), known in Zambia as community health assistants, selected by members of the communities where they live.

Previously, Zambia’s CHWs focused primarily on health promotion and distributing anti-mosquito bed nets. Determined to harness their full potential to diagnose and treat cases of malaria in the community, Zambia expanded the responsibilities of the CHWs and launched a rigorous 10-day training program for them. Today, Zambia’s CHWs serve as a critical first line of defense against malaria and have had a broader set of primary health care services added to their mission. They diagnose and treat cases in their communities, deliver mass drug administration of malaria prophylaxis, and collect data. After nearly 10 years of this more flexible, targeted, and data-driven approach, malaria is once again on the retreat across Zambia. From 2010 to 2020, malaria-related deaths have decreased by 59 percent in Zambia.

Nowhere is Zambia’s success against malaria more evident than in its Southern Province, where CHWs now manage more than 60 percent of malaria cases, leaving health facility teams to tend to other, more complicated, health issues. The country is now exporting lessons and strategies from Southern Province to the rest of the country.

Zambia’s struggles and successes are worth noting for other countries.

Establishing a system for collecting up-to-date data has been a key hurdle across much of the country. Many of its CHWs are located in extremely remote areas, with populations spread across great distances. While the government established a goal of deploying one CHW for every 500 residents, they have yet to achieve that goal – leaving some communities without effective coverage. In addition, many CHWs do not have mobile phone service needed to upload data weekly. The government and its partners have had to scale back expectations from a weekly rapid reporting system to monthly reporting.

That said, the data submitted to district and national health offices helped improve the country’s efforts to control malaria almost immediately, by illuminating trends and helping inform appropriate local interventions. CHWs and health facilities report not only on the number of positive cases, but also on the number of tests performed, as well as the number of test kits and treatment courses in stock. That helps strengthen the supply chain and guides district health offices in planning interventions and activities.

Today, a national dashboard, updated monthly, not only shows malaria hotspots, it also displays district reporting levels to create pressure on districts and incentivize reporting. Bi-annual or annual data quality audits ensure that the data being collected is clean. The government and its partners have also built information systems to display the data in mapping tools and graphs to illuminate trends. The government also uses scorecards from the African Leaders Malaria Alliance.

The data collected using the health management information systems (HMIS) has helped the country leverage another powerful anti-malarial tool – mass drug administration.

Mass drug administration (MDA) is a campaign-style strategy used to administer drugs to at-risk populations in a given area, regardless of disease status. In the case of malaria MDA, antimalarial treatment is provided to every person in an area (except for pregnant women in their first trimester, and infants) at approximately the same time. The medicine works in two ways – it prevents infection and cures asymptomatic cases that act as a reservoir of the disease in the community.

MDA, which is used regularly in Southeast Asia, has not been used in Africa at scale for about 50 years. This is because it is costly, there are lingering questions about its cost effectiveness and it requires reaching everyone in a community, which has been seen as a key hurdle.

But the data Zambian officials were receiving indicated that 16 districts in the country’s Southern province were good candidates for MDA. There was a distinct rainy season that provided a good target time for treatment and existing malaria rates in these districts were relatively low – holding the promise for elimination in some districts. The CHW program also gave them a key partner in the field, in the same way other countries have used CHWs to achieve their health goals.

From 2014 to 2016, the ministry of health and its partners piloted a program to determine proof of concept. The MDA study saw an 87 percent reduction in malaria cases and a 97 percent reduction in facility-reported malaria deaths. By the end of the study, more than half of the health facility areas had zero malaria infections. Zambia has now added MDA to its arsenal of proven interventions, with CHWs and volunteers supporting two rounds of MDA in 16 districts in Southern Province every year.

The use of MDA helped Zambia achieve a key milestone in the areas where it was used: “The total number of confirmed cases is sufficiently small that the [community] health workers can proceed with a case investigation into the household and the neighborhood of an index case,” researchers wrote. Previously, levels of infection were too high to engage in such investigation and follow up. The research, published in the American Journal of Tropical Medicine and Hygiene in 2020, "showed that quality delivery of the standard package of interventions as recommended by the WHO for malaria-endemic countries in sub-Saharan Africa, along with carefully targeted and implemented population-wide drug-based strategies in lower transmission settings, may significantly add to reductions in malaria transmission and, in some areas, may allow national programs to start aiming for subnational malaria elimination.”

Zambia’s health officials are now exploring other regions of the country that might benefit from MDA.

Despite this progress, however, malaria remains one of the leading causes of death in Zambia – causing more than 1,000 deaths a year. A majority of those deaths are of children under five.