Better yellow fever vaccine possible

LEIDEN, Netherlands, Jun 17, 2005 (United Press International via COMTEX) -- Dutch researchers have found the crucial bit of virus that people's immune systems need to spot and quash yellow fever.

Howard Hughes Medical Institute international research scholar Jan ter Meulen, of Leiden University Medical Center, in the Netherlands, said the findings may help scientists improve the existing vaccine, which has rare but severe side effects.

To protect people from the disease, yellow fever vaccines must contain this essential fragment of instruction to the immune system, according to ter Meulen.

The World Health Organization estimates yellow fever, spread by mosquitoes, strikes more than 200,000 people a year, mostly in Africa, killing about 30,000, the Howard Hughes Medical Institute reports.

The findings are published in the journal Virology.