The vector-borne viral infection causes fever and severe joint pain; no vaccines or antivirals targeting the chikungunya virus are currently available. According to The New York Times, more than 150,000 people have now been affected by the disease in 19 Caribbean and South American countries. The US Centers for Disease Control and Prevention reported the first locally acquired infection in Florida last month.
The new study reports the results of a National Institutes of Health-funded Phase 1 clinical trial led by National Institute of Allergy and Infectious Diseases scientist Julie Ledgerwood. The researchers tested different doses of the vaccine for safety and effectiveness in 25 healthy volunteers, who received three shots over a 44 week period. The vaccine, which uses certain structural proteins from the virus capsule, was well tolerated and no serious adverse reactions were reported. Neutralizing antibodies to the viral antigens were detected after the second dose, and a significant boost in antibody levels was seen after the third dose.
The levels of antibodies produced by the vaccine “were comparable to those seen in two patients who had recovered from a chikungunya virus infection acquired elsewhere,” Ledgerwood said in a press release. “This observation gives us additional confidence that this vaccine would provide as much protection as natural infection.”
The work “represents an important step in vaccine development to combat this rapidly emerging pathogen,” the authors wrote in their paper.