NEW research presented in the United States has suggested lyme disease may be sexually transmitted.
Lyme disease is a tickborne infection caused by Borrelia burgdorferi, a type of corkscrew-shaped bacteria known as a spirochete.
The lyme spirochete resembles the agent of syphilis, long recognised as the epitome of sexually transmitted diseases.
Lead author of the study Marianne Middelveen said the findings could explain why the disease was more common than expected if only ticks were involved in transmission.
Last year the US Centers for Disease Control and Prevention announced lyme disease was more common than previously thought, with more than 300,000 new cases diagnosed each year in the United States, making lyme disease almost twice as common as breast cancer and six times more common than HIV/AIDS.
"Our findings will change the way lyme disease is viewed by doctors and patients," Ms Middelveen said.
In the study, researchers tested semen samples and vaginal secretions from three groups of patients: control subjects without evidence of lyme disease, random subjects who tested positive for lyme disease, and married heterosexual couples engaging in unprotected sex who tested positive for the disease.
As expected, all of the control subjects tested negative for Borrelia burgdorferi in semen samples or vaginal secretions.
In contrast, all women with lyme disease tested positive for Borrelia burgdorferi in vaginal secretions, while about half of the men with lyme disease tested positive for the Lyme spirochete in semen samples.
Australian dermatologist Peter Mayne, who was involved in the study, said the presence of the lyme spirochete in genital secretions and identical strains in married couples strongly suggested that sexual transmission of the disease occurred.
"We don't yet understand why women with lyme disease have consistently positive vaginal secretions, whilst semen samples are more variable. Obviously there is more work to be done here," he said.
More information regarding the study can be found at the Journal of Investigative Medicine.