NEW GRANT HELPS RESEARCHER TACKLE UBIQUITOUS TROPICAL DISEASE
COLUMBUS, Ohio – An Ohio State University microbiologist is working to develop a vaccine for leishmaniasis – a usually tropical disease that has infected millions of people and, strangely, thousands of hunting dogs in the northeastern United States.
According to the World Health Organization, an estimated 12 million people worldwide are infected with leishmaniasis, and at least 350 million more are at risk of becoming infected. The vast majority of these people live in warm climates, such as Latin America and the Mediterranean.
Leishmaniasis is transmitted from dogs to humans and other mammals through the bite of a sand fly, an insect indigenous to tropical climates.
Abhay Satoskar, an assistant professor of microbiology at Ohio State, is one of seven researchers – and the only scientist in the United States – to receive a grant this year from the WHO's Special Programme for Research and Training in Tropical Diseases. He'll use the money to try to create vaccines for leishmaniasis, one of 10 tropical diseases that the WHO has designated as a "neglected infectious disease that disproportionately affects poor and marginalized populations."
Satoskar will receive $15,000 – a small award by today's research-grant standards. But the WHO typically doesn't dole out large sums of money, he said; rather, it gives researchers start-up funds to help lay the groundwork for new projects.
"The goal is to develop leishmaniasis vaccines for humans and dogs and, with the WHO's help, figure out logistically how to deliver these vaccines to the areas that need them the most," Satoskar said. "That could significantly decrease the number of people who contract the disease and need treatment."
As far as scientists can tell, sand flies are the only way that leishmaniasis can be transmitted to dogs – the primary carrier of leishmaniasis – and then to other mammals.
Sand flies typically live in warm climates. So how and why so many hunting dogs in the northern United States contracted the disease baffles scientists. However, reports of human leishmaniasis cases in the United States are few and far between, although leishmaniasis has become a problem for troops in Iraq, where outbreaks of "Baghdad Boil" – a term used to describe the blisters caused by Leishmania – are common, said Satoskar.
"The only way to get the disease is by going to an endemic area," he said. "As far as we know, the infected dogs were never taken outside the United States. But it's possible some of the dogs could have been bred or taken to states that border Mexico, where the disease is widespread."
Symptoms of leishmaniasis vary widely, as there are at least 20 species and subspecies of Leishmania parasites. Symptoms range from skin wounds that slowly heal on their own, usually leaving scars in their stead, to the more insidious form of the disease that infects the liver, spleen and bone marrow. Without treatment, the most serious cases can be lethal.
"But even the most severe cases are treatable with drugs," Satoskar said. "The problem is that the disease is endemic in some of the poorest countries in the world, where those infected can't afford the necessary medicine."