by Bob Henson and David Hosansky
Benjamin Lamptey. (Photo by Carlye Calvin)
Across much of the broad belt of sub-Saharan Africa known as the Sahel, a simple headache can be a terrifying omen. It may signify the onset of meningitis, an inflammation of the thin membranes (or meninges) that surround the brain and spinal cord. While there are many causes of meningitis, it’s the type associated with bacteria that leads to large-scale epidemics. Bacterial meningitis sickened more than 250,000 Africans during a record-setting 1996 outbreak. About 25,000 people died.
For reasons that aren’t entirely clear, outbreaks of bacterial meningitis appear to favor the dry, dusty conditions common from November to April across the semiarid stretch from Senegal to Ethiopia known as the meningitis belt (see graphic below). A new project launched with a $900,000 grant from Google.org—the philanthropic arm of the Internet search company—aims to provide up to two weeks’ notice of weather conditions linked to the end of the meningitis season. That, in turn, could help officials allocate vaccines and other scarce resources when and where the risk is highest.
UCAR is coordinating the three-year study, which involves a variety of U.S. and African institutions that are each skilled in a key aspect of the problem. The study could serve as a template for future work at NCAR and elsewhere using weather and climate prediction to support public health. It’s also part of a broader Google push toward an “Earth-gauging system” that will promote early warning of crises in health, food supply, and other areas by integrating and mapping a wide array of environmental, health, and development data.
“This is an opportunity to use our traditional expertise in weather forecasting and our growing expertise in social sciences to help health care officials on the front lines,” says Raj Pandya, coordinator of the UCAR Africa Initiative (see “On the Web”).
Ministries of health in the meningitis belt, with support from the World Health Organization and other partners, wage regular campaigns to immunize as many at-risk residents as possible when epidemics break out. They’re limited by the scant number of vaccines available and the logistical difficulties of trying to reach populations in remote areas. The notion that weather and climate have a role to play in driving these epidemics, and the possibility of using weather and climate information in early warning systems, have been explored for the past decade. However, progress has been slow, says Madeleine Thomson, who heads the Africa Regional Programme at the International Research Institute for Climate and Society (IRI). “Now we can bring a new set of players to the field,” she says.
This graphic shows the parts of the world most prone to meningitis outbreaks. The meningitis belt that roughly corresponds with the semiarid Sahel runs through parts of the countries in red. (Illustration by Percherie, courtesy Wikipedia.)
Along with UCAR and IRI staff, the team includes climate-modeling specialist Fredrick Semazzi (North Carolina State University) and meteorologist Benjamin Lamptey, who got the project rolling. After two years as an NCAR postdoctoral researcher, Lamptey returned to his native Ghana in 2007 and is now hosted by the International Water Management Institute in Accra. In January, he met staff from Google.org who were visiting Ghana. They’d already been working with IRI and others on a health and climate project in East Africa, says Lamptey, “so I suggested that it would be appropriate to have a sister project in West Africa.” Lamptey connected the Google staff with Semazzi, Thomson, and Pandya, and the successful proposal soon emerged. Semazzi took advantage of a sabbatical in Boulder to work with UCAR colleagues in developing the project and building links with U.S. university researchers.
Lamptey is heartened to see meteorologists and health specialists working together in his own country. “This has not been common in Ghana in particular and most parts of Africa as a whole, but the situation is gradually changing,” he says. For example, geographer Aondover Tarhule (University of Oklahoma) is planning a study to link climate and urban health in Accra as well as Ougadougou, Burkina Faso, and Niamey, Niger. There are also plans to set up a climate change and health unit at Ghana’s Kwame Nkrumah University of Science and Technology.
Participants in the Google.org study expect the ball to move sharply forward in December when they convene in Addis Ababa, Ethiopia, for an annualmeeting of the World Health Organization–led Meningitis Environmental Risk Information Technologies consultative group. “This will allow us to reach out to the community, explore previous experiences, and incorporate what is already known into the project,” says Pandya.
Over the next year Lamptey and the Ghana Meteorological Agency will test the usefulness of an ensemble prediction approach, looking at such markers as upward shifts in relative humidity as possible clues to epidemic-ending weather. They’ll call on the vast model archives stored at UCAR as part of the THORPEX Interactive Grand Global Ensemble (see “On the Web”). Meanwhile, Semazzi will network with other university scientists and oversee a testbed for refining the ensemble approach.
By the dry season of early 2011, the team—which includes not only meteorologists but also economists, epidemiologists, public health managers, and experts in data dissemination—hopes to implement a decision support system and assess the first results. “The goal is to get information to the people who need it in time for them to use it,” says Pandya. “If we can make that happen, this system has significant potential to save lives.”
Further down the line, conjugate vaccines, which are designed specifically for bacterial agents, show great promise for controlling meningitis outbreaks. “Once the conjugate vaccine is rolled out everywhere, it is hoped that the big epidemics will be a thing of the past,” says Thomson. Even then, she adds, “It will be very valuable to have a really good understanding of the environmental, climate, population, and bacterial-strain factors for evaluating the new vaccine. The Google/UCAR project will engage the region’s weather and climate community and help us understand much better what is going on.”