Chikungunya Vaccine Showed Promise

Chikungunya vaccine produced antibodies in human trial

(RxWiki News) Facing more than 570,000 chikungunya cases in the Americas and 484 in the US as of early August, officials have been scrambling to slow the spread of the virus. One vaccine may have the potential to help.

A vaccine recently tested in humans for the first time produced a strong immune response to chikungunya.

Chikungunya is a viral sickness transferred through infected mosquitoes. Common symptoms are fever, headache and debilitating joint pain. Symptoms usually resolve within a few weeks, but joint pain can persist.

"Seek medical care if you have a fever, headache or joint pain."

Although the results of the recent National Institute of Allergy and Infectious Diseases (NIAID) test are not conclusive, they did suggest the vaccine could "provide durable protection against the disease."

The NIH press release indicated that all 25 study volunteers produced antibodies (blood proteins that fight diseases) to chikungunya after two injections of the vaccine. The third boosted the immune response even further.

These antibodies remained in the volunteers' bodies for longer than 11 months.

“The candidate vaccine prompted a robust immunological response in recipients and was very well tolerated,” said Julie E. Ledgerwood, DO, Vaccine Research Center scientist and principal investigator, in a press release. “Notably, the levels of neutralizing antibody produced in response to the experimental vaccine were comparable to those seen in two patients who had recovered from a chikungunya virus infection acquired elsewhere. This observation gives us additional confidence that this vaccine would provide as much protection as natural infection.”

The experimental vaccine differs from other vaccines. Most vaccines are made from dead or damaged viruses, but researchers made the new chikungunya vaccine with a virus-like particle (VLP). VLPs contain the outer shell of the virus — but none of the genetic material the virus would need to multiply inside the body.

VLPs don't have to be produced under high-security conditions because they do not pose a threat of the virus spreading.

NIAID Director Anthony Fauci, MD, said the research into a chikungunya vaccine was necessary.

“The two species of mosquito that spread chikungunya virus are found in parts of the continental United States, so it may just be a matter of time before this illness gains a foothold here,” he said in a press release. “Therefore, it is prudent to begin addressing this emerging public health threat with the development of vaccines, such as this one, which was designed and tested by scientists from the NIAID Vaccine Research Center.”

Review Date: 
August 15, 2014