A University of Victoria researcher says she and a colleague are close to developing a vaccine for syphilis, a disease that has reached its highest rates in B.C. in 30 years.
Microbiologist Caroline Cameron and Sheila Lukehart, a professor in the University of Washington's department of global health, have received a nearly $3-million grant from the U.S. National Institute of Allergy and Infectious Diseases at the National Institutes of Health. The grant will help fund preclinical trials.
Dr. Cameron has studied the sexually-transmitted infection for two decades and runs the only lab in Canada that researches how the pathogen that causes it spreads throughout the body. Dr. Lukehart's research focuses on the initial stage of the disease: preventing the formation of a chancre that is unique to syphilis.
"If we combine in a vaccine cocktail her protein that prevents the lesion from forming and my protein, which prevents the organism from spreading in the body, then we should be able to combat what causes the disease," Dr. Cameron said.
The grant, which will cover a four-year period of research, will allow the two to test on animals the effectiveness, optimal dose and longevity of the vaccine cocktail.
"We're hoping at the end of that period to be at a point where we will have a great idea of whether this will be it, or we have to tweak it," Dr. Cameron said.
Almost 400 cases of infectious syphilis have been reported in B.C. in the first half of 2016, said Jason Wong, a physician epidemiologist with the B.C. Centre for Disease Control. This is about 25 per cent higher than the same period last year, though a projection would put the year-end total at about 4 per cent higher than last year's total of 761 cases.
Of last year's total, almost 500 cases were reported in the Vancouver Coastal Health (VCH) region – more than double the number of cases reported a decade ago – prompting the health authority to initiate a formal outbreak response early this year.
Dr. Wong said there are various possible factors as to why numbers have climbed year-over-year since about 2010, one being increased awareness and testing.
"We do know that testing volumes have gone up – more people are testing for syphilis, and testing for syphilis more regularly – so one reason for the increase may be that we're able to catch more of it," he said.
Another possibility is that great advancements to HIV treatments – which can now virtually eliminate progression of the disease to AIDS and reduce transmission of the virus by 96 per cent – have led to changing behaviours.
"I think it has changed the way that people think about HIV, and how concerning HIV is," Dr. Wong said. "We may be seeing changes in behaviours – namely, reduction of condom use – in the era of very good HIV treatment."
People infected with syphilis are also between two and five times more likely to acquire or transmit HIV, Dr. Cameron said.
Dr. Wong called the vaccine research a very promising and exciting technological advancement.
About 36 million people worldwide are currently infected with syphilis and about 11 million new infections are diagnosed per year, according to the World Health Organization. The disease is difficult to diagnose clinically, because symptoms such as painless sores and rashes are often mistaken for symptoms of another ailment.
If detected early, syphilis can be effectively treated with a penicillin shot. If detected in a tertiary stage, the intravenous antibiotics can be effective, but there may be irreversible damage to organs and tissues.
About 97 per cent of all syphilis diagnoses are male and about 90 per cent identify as gay, bisexual, or men who have sex with men, according to VCH.
The pathogen crosses placental barriers; about 1.4 million pregnancies worldwide are affected by syphilis each year, Dr. Cameron said. The majority of those pregnancies result in stillbirths.