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Is Lyme Disease Contagious?

Very interesting research that may change how we view Lyme Disease - that the bacterium Borrelia burgdorferi — the cause of Lyme disease — may be a contagious illness, sexually transmitted between partners. From the January 27, 2014 Medical Daily:

Is Lyme Disease Contagious? Clues Hint That It May Be A Sexually Transmitted Disease

 A new study published in the Journal of Investigative Medicine suggests the bacterium Borrelia burgdorferi — the cause of Lyme disease — may be a contagious illness, sexually transmitted between partners.

The transmission from person-to-person has been an idea refuted by the CDC who believes it is solely transmitted to humans through the bite of an infected blacklegged tick. “The CDC position on sexual intra-human Borrelia burgdorferi transmission is that it does not occur,” the agency said in a 2011 statement.

The study — presented at the annual Western Regional Meeting of the American Federation for Medical Research — a collaborative effort by an international team of scientists — tested semen samples and vaginal secretions of three groups of patients to investigate whether passing Lyme disease to a partner through unprotected sex is a possibility. The study observed 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. The presence of B. burgdorferi and identical strains of the bacterium were of particular interest to the researchers in unprotected sex in spouses.

The control subjects were found to test negative for the bacterium in semen samples or vaginal secretions, as expected by the researchers. The researchers found traces of B. burgdorferi in the vaginal secretions of all women with Lyme disease. In contrast, approximately half of the men with the disease tested positive for the bacterium in semen samples. In addition, one of the heterosexual couples with Lyme disease were found to have identical strains of the bacterium in their genital secretions.

A surprising finding for the researchers was why women with Lyme disease had consistently positive vaginal secretions, compared with the semen samples that showed greater variability. Although this warrants further research, overall, the results indicate the presence of the bacterium in genital secretions and identical strains in married couples, which means the disease may be contracted through sexual transmission. “Our findings will change the way Lyme disease is viewed by doctors and patients,” said Marianne Middelveen, lead author of the study presented in Carmel, 

The possibility of Lyme disease being a sexually transmitted disease could help explain the increase in reported cases throughout the years, suggesting ticks aren’t the only way of infection. The disease is commonly undiagnosed due to the signature “bull’s eye rash” absence in nearly half of those who are infected.