Hello, I'm David Townes. Medical Epidemiologist in the Emergency Response and Recovery Branch at the Centers for Disease Control and Prevention. In this video, we will review malaria and it's role and impact in complex humanitarian emergencies. Malaria is endemic in approximately 100 countries around the world, comprising about half the world's population. Many of these countries are resource poor with high percentages of the population living in poverty. If we were to highlight countries on this map that are prone to or have sustained complex humanitarian emergencies, many of those countries would also be where malaria is endemic. According to the 2015 World Malaria Report produced by the World Health Organization. In 2015 there were approximately 214 million cases of malaria worldwide. Resulting in approximately 438,000 deaths. The vast majority of these deaths, approximately 88%, occurred in sub-Saharan Africa. The majority of these were in children younger than five years old. While there is still a long way to go, there is some good news. According to the 2015 World Malaria Report. Between 2000 and 2015 malaria incident rates fell by 37% globally and by 42% in Africa. During that same period, malaria mortality rates fell by 60% globally and by 66% in Africa. This is due to a variety of factors including malaria control programs. Many of which are partnerships between international and local organizations, and most importantly local communities. Let's talk a bit about malaria infection in humans. Malaria is a protozoan infection. There are four main species of malaria that infect humans. Plasmodium falciparum, Plasmodium vivax, Plasmodium ovale, and Plasmodium malariae. Plasmodium falciparum accounts for both the majority of infections and the majority of deaths worldwide. Followed by Plasmodium vivax. The vector for malaria is the female Anopheles mosquito. There are approximately 400 different species. But in terms of malaria transmission, about 30 are considered important. These are generally night-biting mosquitoes. Some rest indoors and some rest outdoors. We will discuss this later on in the talk, as it has implications for malaria control measures. As you can see here, malaria has a complex life cycle. Comprised of a mosquito stage, shown on the left. A human liver stage on the top right, and a human blood stage on the bottom right. For the sake of this talk, however, we can simplify that into a simple vector host relationship between humans and mosquitoes. A person may be infected with malaria when they are bitten by a mosquito carrying the malaria parasite. Similarly, when a mosquito without the malaria parasite bites a person already infected with malaria, that mosquito may acquire the malaria parasite and subsequently go on to infect another person with malaria. It is important to understand this relationship to understand the role and impact of malaria in complex humanitarian emergencies. Keeping in mind the relationship between the human population and the mosquito outlined the previous slide. In a setting of complex humanitarian emergencies, we must consider not only the relationship between the displaced population and the mosquito. But also the specific environment or context of the emergency. During a complex humanitarian emergency, there is displacement of the population. In terms of malaria transmission, it is important to understand the context or environment of the emergency. Often, displaced populations live in overcrowded conditions that may increase malaria transmission. Displaced populations often have inadequate shelter that may also result in increased malaria transmission. As water is critical for survival, displaced populations often settle near sources of water. This water source may also be a breeding site for mosquitoes. Finally, it is important to know the habits of the local mosquitoes. Do they tend to bite at a certain time? In the evening or late at night? And once they bite, are they indoor or outdoor resting? As part of understanding the environment or context of the emergency, it is important to understand the displacement of the population as it may influence malaria transmission. Where do they come from? Where are they now? And how did they get from there to here? The displaced population left their area or country of origin, traveled through areas or countries, finally settling in a new area or country. It is important to know if malaria is endemic in each of these. If, for instance, a displaced population is from an area where malaria is not endemic, and they settle in an area where malaria is endemic. The population may be at high risk for malaria. Similarly, if the displaced population travels through an area where malaria is endemic but settles in an area where malaria is not endemic, they may bring malaria with them. In fact, when we look at refugees, internally displaced persons, returnees, and other persons affected by humanitarian emergencies. Almost two-thirds live in malaria endemic regions. In addition, a study examining the burden of malaria in post-emergency refugee populations, analyzed malaria incidence and mortality from 2006 to 2009. The study utilized data from the United Nations High Commissioner for Refugees Health Information Systems database. That collected data in 60 camps in 8 African countries as well as Thailand. One important finding of this investigation, was that malaria was the cause of 16% of deaths in refugee children younger than five years old in all of the study sites. Finally, let's discuss malaria control in the context of complex humanitarian emergencies. The basic objective of a malaria control program should be to prevent morbidity and mortality from malaria and prevent further cases of malaria. This is done through prevention and case management. While each complex humanitarian emergency is different. And the appropriate prevention in treatment approaches must be specific to the contacts. The most common prevention matters include, long lasting insecticide treated bed nets or LLINs. And indoor residual spraying or IRS. Case management includes timely and accurate diagnosis and timely and effective treatment. Long lasting insecticide treated bed nets or LLINs, have been the mainstay of malaria prevention in complex humanitarian emergencies. Indoor residual spraying or IRS, has also been used. But tends to be used more in semi-permanent settlements, with structures with absorbent walls. Rather than early on in the emergency, when the population may be living under plastic sheeting that lends itself less well to IRS. As we discussed earlier, it is important to understand the behavior of the local mosquito in terms of outdoor resting or indoor resting. As it may influence if and how IRS is used as a prevention measure. Finally, case management includes both diagnosis and treatment. The two most common methods for malaria diagnosis are microscopy, visualizing the malaria parasite under a microscope, and rapid diagnostic tests or RDTs. Given the resource needs to maintain a microscopy program, RDTs tend to be used in complex humanitarian emergencies. Especially early on in the crisis. Once a case of malaria has been identified through one of the methods just discussed, patients should be treated with safe and effective anti-malarial medications. Where there is regional variation based on the species of malaria, a national malaria control guideline should be followed. The current World Health Organization guidance for the treatment of uncomplicated Plasmodium falciparum malaria infection includes artemisinin combination therapy, or ACT. Some important take home points. Populations displaced by complex humanitarian emergencies may be at high risk for malaria for a variety of reasons, some of which are specific to displaced populations. It is important to understand the relationship between the displaced population, the mosquito, and the environment. A malaria control program should include both prevention interventions such as LLINs. And case management, including accurate and timely diagnosis, and timely and effective treatment often with ACTs. Thank you.
