Vaccine Shows Promise Against Mosquito-Borne Virus
Volunteers developed antibodies to chikungunya in first human trial, but shot for public use 5 years away, researcher says
By Steven Reinberg
THURSDAY, Aug. 14, 2014 (HealthDay News) -- An experimental vaccine to protect people from the mosquito-borne chikungunya virus has shown promise in its first human trial.
"This vaccine was safe and well-tolerated, and we believe that this vaccine makes a type of antibody that is effective against chikungunya," said trial leader Dr. Julie Ledgerwood, chief of the clinical trials program at the U.S. National Institute of Allergy and Infectious Diseases.
Currently, there are no vaccines or drugs to treat this debilitating infection, which causes fever and intensely painful, severe arthritis.
Chikungunya has spread from its origins in Africa to Asia and the Caribbean, including Puerto Rico and the U.S. Virgin Islands. Last month, the first U.S. cases were reported in Florida, according to the U.S. Centers for Disease Control and Prevention.
The new report was published online Aug. 15 in The Lancet.
Ledgerwood said the next step is to test the vaccine in more people and more age groups. The current study looked at 25 people who were between the ages of 18 and 50. The vaccine also needs to be tested in populations where the virus is endemic, to see if it really prevents people from getting the disease, she added.
Testing will take more than five years before a vaccine could be offered to the public, however, Ledgerwood said. Should the vaccine prove safe and effective, it could be given to people living in areas where chikungunya is endemic and also to travelers and military personnel going to those places, she said.
"In areas where this virus is active, people feel the need for the vaccine is great," Ledgerwood said.
Chikungunya (pronounced chick-en-gun-ye) virus causes high fevers, joint pain and swelling, headaches and a rash. For some people, the pain can last even after other symptoms disappear, and in rare cases it can be fatal, the CDC said.
Ann Powers, a CDC research microbiologist and author of an editorial in the same journal, said, "There are a number of approaches going on with chikungunya vaccine, and I am excited to see one is moving forward in clinical trials."
Powers added that in areas like India, where chikungunya is endemic, a vaccine has been needed for years. "Now that chikungunya is in the Western Hemisphere, there is no reason not to suspect it won't be endemic in Central or South America," she said.
And as more cases show up in the southern United States, it is likely that local outbreaks will increase, Powers said. "Given the ability of mosquitos to transmit the virus, we could see outbreaks in other areas of the country," she said.
There may even come a time when the vaccine will be needed in the United States, Powers added.