Sexually Transmitted Disease: Prevention Still Better Than Cure
Sexually Transmitted Disease: Prevention Still Better Than Cure
Sept. 20, 2000 (Toronto) -- Fledging vaccines to ward off herpes and genital warts have passed early tests on the way to the clinic. The new vaccines promise not only to prevent people from being infected but also to ward off serious complications of sexually transmitted diseases (STDs) such as cervical cancer and a brain infection caused by herpes. They could also lower the risk getting of HIV, researchers reported here at a meeting of infectious disease specialists.
Vaccines against genital herpes are among the furthest along, says Richard Whitley, MD, professor of pediatrics at the University of Alabama in Birmingham.
Earlier this week, researchers presented results of two human studies of a herpes vaccine that prevented genital herpes symptoms in some women, although not in men, nor in women who had been infected with the herpes virus that causes cold sores.
Several other herpes vaccines are in the pipeline, each of which uses different tactics to provoke the immune system to attack the virus, Whitley says. One of the vaccines was tested for safety in a small study and generated a "beautiful immune response," Whitley says. It's now being tested for safety and efficacy in a larger study involving 800 patients.
Blocking infection by the herpes virus responsible for causing genital herpes could also prevent rare, and potentially fatal, cases of encephalitis, a brain infection that usually occurs in newborns or people with weakened immune systems. The virus has this tendency to go into hiding in nerve cells and can re-emerge much later to cause dangerous brain infections.
Researchers have also developed promising vaccines against the virus that causes genital warts, says Denise Galloway, PhD, of the Fred Hutchinson Cancer Research Center in Seattle. By fighting back these infections, the vaccines could also help to prevent cervical cancer since the same virus is thought to play a role in about 95% of cervical cancer cases. It has proven safe for women in early tests with a study being planned later this year to see if it can prevent the progression of cervical cancer in women showing signs of the disease, Galloway says.
Other researchers are working to devise vaccines against gonorrhea, syphilis, and chlamydia, but although some look good in animal tests, they have been less successful in humans. Antibiotics can control both syphilis and gonorrhea, but patients tend to get reinfected.
All of these vaccines may have far-reaching implications. A person is more easily infected with HIV, the virus that causes AIDS, when they have another STD. Therefore, although scientists have had little success in developing an HIV vaccine, these other vaccines could ultimately reduce the number of patients with HIV.
Vaccines against genital herpes are among the furthest along, says Richard Whitley, MD, professor of pediatrics at the University of Alabama in Birmingham.
Earlier this week, researchers presented results of two human studies of a herpes vaccine that prevented genital herpes symptoms in some women, although not in men, nor in women who had been infected with the herpes virus that causes cold sores.
Several other herpes vaccines are in the pipeline, each of which uses different tactics to provoke the immune system to attack the virus, Whitley says. One of the vaccines was tested for safety in a small study and generated a "beautiful immune response," Whitley says. It's now being tested for safety and efficacy in a larger study involving 800 patients.
Blocking infection by the herpes virus responsible for causing genital herpes could also prevent rare, and potentially fatal, cases of encephalitis, a brain infection that usually occurs in newborns or people with weakened immune systems. The virus has this tendency to go into hiding in nerve cells and can re-emerge much later to cause dangerous brain infections.
Researchers have also developed promising vaccines against the virus that causes genital warts, says Denise Galloway, PhD, of the Fred Hutchinson Cancer Research Center in Seattle. By fighting back these infections, the vaccines could also help to prevent cervical cancer since the same virus is thought to play a role in about 95% of cervical cancer cases. It has proven safe for women in early tests with a study being planned later this year to see if it can prevent the progression of cervical cancer in women showing signs of the disease, Galloway says.
Other researchers are working to devise vaccines against gonorrhea, syphilis, and chlamydia, but although some look good in animal tests, they have been less successful in humans. Antibiotics can control both syphilis and gonorrhea, but patients tend to get reinfected.
All of these vaccines may have far-reaching implications. A person is more easily infected with HIV, the virus that causes AIDS, when they have another STD. Therefore, although scientists have had little success in developing an HIV vaccine, these other vaccines could ultimately reduce the number of patients with HIV.
