Experimental vaccine works against Chikungunya

* Mosquito-borne virus is very painful but rarely fatal

* Trade, travel, climate change boosting mosquito species

* Next step is human testing, researchers say

By Maggie Fox, Health and Science Editor

WASHINGTON, Jan 28 (BestGrowthStock) – An experimental vaccine
works against the newly spreading Chikungunya virus, at least
in monkeys, and the approach may also work against other exotic
viruses, U.S. government researchers reported on Thursday.

They used virus-like particles, which are mock versions of
the virus that resemble an empty shell, to vaccinate monkeys
against the rarely fatal but painful mosquito-borne infection.

“At a time when there are no commercially available
vaccines … a virus-like particle vaccine has the potential to
have a considerable impact on the spread of this disease,” Dr.
Gary Nabel of the National Institute of Allergy and Infectious
Diseases and colleagues wrote in the journal Nature Medicine

They said the same approach may be useful similar
mosquito-borne viruses, known as alphaviruses.

Chikungunya, first seen in the 1950s, came back in 2004 and
2005 and has since spread to nearly 20 countries to infect
millions. The U.S. Centers for Disease Control and Prevention
has a map at http://www.cdc.gov/ncidod/dvbid/chikungunya/
CH_GlobalMap.html.

It is rarely fatal but it causes debilitating pain and
exhaustion and can have long-term or even permanent effects.

“Changes in trade, travel and global climate have aided the
spread of mosquito species worldwide, which may potentially
cause other alphavirus outbreaks,” they wrote.

“Our approach may prove useful for vaccine development
against other pathogenic alphaviruses, including Western,
Eastern and Venezuelan equine encephalitis viruses,
O’nyong-nyong virus and Ross River virus.”

O’nyong-nyong virus is similar to Chikungunya and is found
in Uganda, while Ross River virus affects Australia, Papua New
Guinea and other Pacific islands.

People have tried to make a Chikungunya vaccine but one
attempt caused similar symptoms to infection and others did not
do well in testing.

Nabel’s team tried making virus-like particles, an approach
that Merck and Co (MRK.N: ) uses in a vaccine against the human
papillomavirus that causes cervical cancer.

These particles resemble hollowed-out viruses, which the
body can recognize and attack. They cannot cause infection on
their own.

Vaccinated monkeys fought off infection and the antibodies
their bodies made against Chikungunya also protected mice,
Nabel’s team reported.

“Because virus-like-protein-based vaccines are currently
safely used in people for protection against hepatitis B and
human papillomavirus infections, they may prove to be a
practical candidate for Chikungunya vaccine efforts,” the
researchers wrote.

Nabel said the next step is human testing.

Maryland-based vaccine maker Novavax (NVAX.O: ) has been
using virus-like particles to make vaccines against influenza
and has teamed up with Cadila Pharmaceuticals (CADI.BO: ) in
India to make vaccines they hope will work against influenza
and perhaps dengue fever and Chikungunya.

Stock Market Research
(Editing by Eric Walsh)

Experimental vaccine works against Chikungunya