It’s been 11 months since I embarked on my last adventure (hiking the entire Pacific Crest Trail) and now I’m in transit to the next one, this one for work. Two weeks ago I started a new job working at the University of California, San Francisco in the Malaria Elimination Initiative (MEI). The name of the department is pretty self-explanatory: MEI works with and in countries with a low burden (few cases) of malaria, with the goal of halting local transmission and ultimately eliminating the parasite. There are 34 countries in the world who are working toward malaria elimination, according to MEI (although any country can say they are working on it, without actually *doing* anything). Most of the countries are in southern Africa and Southeast Asia.
In particular, Namibia, in south western Africa, is aiming to eliminate local transmission of malaria by 2020. They have made great strides toward this goal, but now that malaria is under control and not present in most of the country, the government needs to change tactics in order to go from a few cases of malaria to zero cases. That’s where UCSF and MEI come in. Namibia’s Ministry of Health and Social Services (MoHSS), the University of Namibia (UNAM), and MEI have been working together since 2012 to improve the country’s malaria surveillance system and capacity for operational research. Namibia has now implemented reactive case detection (RACD) in much of the country, but these efforts will probably not be enough to eliminate malaria. In reactive case detection, when someone comes to a clinic or hospital and is diagnosed with malaria (via a rapid diagnostic test, RDT, or microscopy) and treated, then theoretically, an official from the MoHSS will travel to that person’s home and test everyone who lives in the same house and any house within 200 meters of it. Since the mosquitos that spread the malaria parasite don’t typically fly very far, the people spend a lot of time close to a malaria case are at the highest risk of contracting the disease. Any close contact to a case who tests positive for malaria would be treated with a standard 3 day course of Artinimisinin combination therapy (ACT). This works great when there is a lot of malaria parasite in someone’s blood because then the RDT is very sensitive and specific. However, in areas of low transmission, such as Namibia, it has been shown that some people will harbor the parasite in their blood but not show any symptoms; they don’t feel sick (or sick enough to seek treatment) and they can also test negative by the RDT, but they can still transmit the parasite to a mosquito and hence to another person. While RACD is great in some situations, it is probably not enough to eliminate malaria.
To try to interrupt transmission, UNAM, MEI, the Gates Foundation and the Novartis Foundation are now working together on a clinical trial comparing RACD to targeted parasite elimination (TPE). TPE, is a system in which the people who are at highest risk of contracting malaria, the people who live in the same house or a house within 200 meters of someone diagnosed with malaria, are presumptively treated, or given malaria drugs to take even though they have not been diagnosed as having malaria. TPE is a type of mass drug administration (MDA) which is very common in some parts of the world for several diseases and TPE has been shown to be effective in stopping malaria transmission in China. However, it has never been attempted in Africa and no one knows if it is feasible, cost effective, accepted by the local people, or is better than RACD. In the study that I will be taking part in, we will test the hypothesis that TPE is more effective than RACD at decreasing malaria incidence.
In addition to testing TPE vs. RACD, the study will also test whether indoor residual spraying (IRS) or reactive vector control (RAVC), or spraying the inside of index cases’ houses, provides an additional benefit. The MoHSS does annual spraying of houses in high risk areas but some houses are missed or not sprayed well, so we are testing whether an additional level of spraying, with a different insecticide, will make a difference.
The difficulty in doing this type of research is that there are not that many cases of malaria in Namibia. In 2001 there were over 500,000 reported cases but in 2013 there were only 4,700 in the country. That is amazing progress, but there is the risk that there won’t be enough cases in each arm of this study to statistically detect a difference in incidence over the two years that the study is going on. While we want fewer cases of malaria, we want enough cases to know that TPE with or without IRS made a difference.
And now, I’m on my way to Namibia to help collect the data for this study. For those who don’t know, Namibia is in south west Africa. It borders South Africa, Bostwana, Angola, and Zambia. Most of Namibia is desert and doesn’t have malaria, however, there is a small strip of land in the northeastern part of the country which extends out like a pot handle and is right on the Zambezi River and hence part of the Okavango delta. With the rain and river, this area is at higher risk of malaria transmission and is where I will be working (I’ll add a map later because I’m having difficulties with it now).
The region where I will be working is called the Zambezi region (named after the river) and the town I will be based in (after a weekend in the capitol, Windhoek) is called Katima Mulilo, or Katima for short. It is right on the Zambezi River and is a regional capitol. Since Namibia is a relatively rich country, people from Angola, Zambia, Zimbabwe, and other countries come to Katima to buy goods and food not available elsewhere and also come here for work. With all of the cross-border travel, there is an increased risk of someone importing malaria (and other diseases) to this region.
Because of the proximity to the river, the main economic driver in the area is agriculture. During some seasons of the year, farm workers and laborers are outside in the fields late at night, which is when the mosquitos that transmit malaria are most active. That means farm workers have an increased risk of getting malaria.
Another common activity, other than hanging out at outdoor bars (because it is so warm at night) is attending night churches. These church gatherings are also outside, so there are several different demographics of people at increased risk of malaria in this region.
I’m not sure why this sliver of land belongs to Namibia versus another country (but that is a question I will definitely figure out once I’m there), but the people who are native to the area speak a different language (SiLozi) than most other people in Namibia. Because of this and the distance to Windhoek, the Zambezi region has often been neglected by the central government and doesn’t get the resources that it really needs. There is a UNAM campus in Katima and I’m told that the town has two restaurants and a decent grocery store. Based on this alone, it already sounds better than the Northwest Province of South Africa where I was working two years ago.
Right now I’m in Johannesburg where I will spend the night before flying to Windhoek in the morning. I’ll be in Windhoek until Monday morning when my colleague, Kate, and I will fly to Katima and I’ll start going into the field to supervise data collection. It’s hard to believe that just over two weeks ago I didn’t have a job and now I am half way around the world, embarking on a new adventure. I hope you will join me and will enjoy reading about it.