Vaccine against Haemophilus ducreyi which causes chancroid has been shown to prevent the transmission of HIV as well. Experiments conducted in pigs with this vaccine have shown to prevent or reduce the painful open sores of chancroid on the genitals and thereby reduce the transmission of HIV,
Chancroid is a highly contagious STD that is common in Africa and today becoming more common in the United States as well. Antibiotics can be used to effectively treat chancroid. If left untreated, chancroid can lead to the transmission of HIV.
Lead researcher Dr. Christopher Elkins at the University of North Carolina in Chapel Hill, and his associates purified a part of the bacteria, Haemophilus ducreyi and vaccinated pigs on days 1, 21, and 42. The researchers tested the pigs three weeks later with Haemophilus ducreyi.
In addition it was found that lesions of the vaccinated pigs were sterile while biopsies of all the 17 placebo-vaccinated pigs showed the presence of viable Haemophilus ducreyi. The blood of the vaccinated pigs also had high levels of antibodies against the chancroid bug.
Elkins explained that the prevention of chancroid lesions could help to reduce transmission of HIV because 'high concentrations' of HIV-susceptible cells are often present in chancroid ulcers.