Twenty-five years ago, I went to western Kenya as a Centers for Disease Control and Prevention (CDC) Epidemic Intelligence Service (EIS) officer to study an outbreak of severe anemia. No one was sure of the cause. Was it parvovirus, or exposure to an environmental toxin, perhaps? In the hospital there were five or six sick children to a bed, and they were so anemic that their blood looked more like a pinkish fluid than the rich red to which we are accustomed. As it turned out, there was no exotic cause. I was seeing the ravages of drug-resistant malaria at a time when chloroquine, the routinely used antimalarial drug, was failing globally.
That kind of grim hospital scene is much rarer these days, thanks to the enormous investment in malaria programs in Africa over the past decade and the improvements these investments have made possible. Programs that provide proven interventions—artemisinin-based combination therapies (ACTs), insecticide-treated bed nets (ITNs), and indoor residual spraying (IRS)—have achieved a 33% reduction in malaria deaths in the African region and 1.1 million lives saved globally. We have much more to do, but this is a reason to celebrate. As we celebrate, however, we must realize that we are also in the midst of a very fragile situation for three major reasons.
Commitment. While global funding for malaria has increased eight-fold since 2000, in the last 2 to 3 years, it has plateaued / decreased. Instead of accelerating to get over the hill, we are starting to coast before we’ve crested the peak—which could result in an unwanted change of direction. A recent review of 75 malaria resurgences during the 20th century found that about 9 out of 10 were due in part to the weakening of malaria control programs, with resource constraints the most common cause. If our investment tails off, it isn’t a question of whether malaria will resurge, but rather how bad the situation will be when it does.
Surveillance. Any good program needs to know where the problem is in order to target resources. For years, malaria programs have gotten by with poor-to-nonexistent surveillance (everyone who had fever was assumed to have malaria), and because there was so much malaria in so many places, the “do everything everywhere” approach made sense. With success in preventing illnesses and deaths and reducing transmission comes the need to focus. That means diagnosing malaria with a laboratory test, tracking and reporting malaria cases, and acting on that information promptly. Rapid diagnostic tests and advances in mobile technology now give us the tools to do surveillance better and faster, but these need well-trained staff to deploy them effectively. And surveillance is not only for cases; it must also include information on how our tools are performing – where drug and insecticide resistance are looming threats. Although sometimes the concept of “health systems strengthening” seems a bit abstract, there is no more concrete example of this than training people and providing them with the tools/systems they need to carry out effective public health surveillance and response for problems like malaria. We want to go high, but we cannot get there flying blind.
Research on new or improved tools. Our current tools are grounded in decades of basic, applied, and operational research. These are highly effective, powerful tools, but they will not stand us in good stead forever. The malaria parasites and their mosquito vectors change every day to evade the weapons we use to kill them. Increasing parasite resistance to drugs and increasing mosquito resistance to insecticides are sure bets. Our tools and strategies also need to adapt and evolve. Now is the time to invest in new drugs, insecticides, and approaches for the future. While developing brand new compounds takes many years, understanding how to use better our existing tools—novel combinations of vector control tools, or creative uses of drugs for prevention, for example—can help us continue to stay ahead of our elusive foes.
Doing all of these does not guarantee continued success, but if we do not do them, we all but assure ourselves of failure. None of us wants to go back to the days when hospital beds were packed with children suffering and dying from severe malaria.