Dust and Meningitis in the Sahel
Recent research carried out in Niger by Columbia University’s International Research Institute for Climate and Society (IRI) will hopefully allow scientists to be able to forecast meningitis outbreaks in sub-Saharan Africa, and thus prevent potential casualties of the disease.
The research was done by IRI in partnership with the NASA Goddard Institute for Space Studies. They found that environmental and climatic factors such as wind and dust conditions have an incredibly strong correlation with meningitis outbreaks in what is called the “meningitis belt,” stretching across the Sahel from Senegal to Ethiopia.
Bacterial meningitis occurs throughout the world but rates of meningitis in the Sahel and the rest of the belt are much higher. The African Meningococcal Carriage Consortium (MenAfriCar) reports that death rates of the disease are between five and 10 percent. However, long-term effects often ensue, including blindness, hearing loss and brain damage.
The outbreaks occur in the dry season and taper off with the first rains, and researchers have often believed that the mineral dust irritates the epithelial cells lining the nose and throat, allowing for easy passage of the bacteria into the bloodstream.
In the initial phases of the study, researchers collected a number of dust samples from Ghana, Niger and Senegal, examining the dust’s characteristics in order to see which properties might be influencing the spread of the disease.
Along with this information, the researchers also looked into environmental factors such as temperature and humidity and social factors such as reduced ventilation. A number of variables are being taken into account to understand how dust is affecting people’s vulnerability to meningitis.
The hopes of the study are that these climatic factors will help public health researchers to forecast meningitis outbreaks and develop vaccination strategies earlier in advance.
One of the lead researchers in the study, Carlos Perez Garcia-Pando, stated, “We’ve known that the disease is associated to climate and environmental issues for a long time, because it’s very seasonal. The idea was to try to use models and observations from satellites and all kinds of data on potential (climate-related) parameters that might be affecting the disease, and try to use that information to provide advance warning.”
Currently in the Sahel, a new vaccine has been distributed which has decreased the outbreak of meningitis. However, vaccination drives are still delivered in districts that are already suffering outbreaks, and they often come too late.
This study has shown that environmental factors can greatly impact the effectiveness of vaccination programs, and this has great implications for the future of meningitis control strategies across the globe.
– Mollie O’Brien
Sources: Irin News, The Guardian
Photo: National Geographic