At St. Jude Children's Research Hospital, Drs. Karen Slobod and Julia Hurwitz have been working for more than a decade on a vaccine to protect against the AIDS virus. Although medications have helped transform AIDS from a rapidly fatal to a chronic disease, there is still no vaccine or cure.
Human testing with the experimental vaccine began in the late 1990s. In a statement, Dr. Elaine Tuomanen, chairwoman of St. Jude's department of infectious disease, said a final round of safety testing is expected to begin early next year. She indicated the next step will be determined by those results along with the immune response the vaccine sparks.
On the University of Tennessee Health Science Center campus, Dr. Gerald Byrne is targeting chlamydia. Byrne is a UT Health Science Center professor and molecular sciences department chairman.
A microbiologist by training, he's been chasing chlamydia since the 1970s.
Today the bacteria is recognized as the cause of the nation's most common sexually transmitted disease (STD) and a leading cause of infertility in women. Different strains are also linked to pneumonia, blindness in the developing world and possibly even heart disease.
Although chlamydia is easily cured by antibiotics, it causes few if any symptoms in women and so often goes untreated.
Byrne's laboratory in the molecular sciences building is devoted to studying different versions of the germ.
"The easy (infectious diseases) we have vaccines for. The ones we are dealing with now (in vaccine development) are tough," Byrne said.
The challenge with chlamydia is to design a vaccine that protects against infection, but doesn't trigger the chronic inflammation responsible for infertility and other problems, he said. A human vaccine is likely at least six years away.
Federal health officials estimate that 2.8 million Americans become infected with chlamydia every year, primarily through sexual contact.