ÎÛÎÛ²ÝÝ®ÊÓƵ-CHUM study: 56 per cent of young adults in a new sexual relationship infected with HPV
A groundbreaking study of couples led by Professor Eduardo
Franco, Director of ÎÛÎÛ²ÝÝ®ÊÓƵ University's Cancer Epidemiology Unit,
in collaboration with a team of colleagues from ÎÛÎÛ²ÝÝ®ÊÓƵ and
Université de Montréal/Centre Hospitalier de l'Université de
Montréal (CHUM), found more than half (56 per cent) of young adults
in a new sexual relationship were infected with human
papillomavirus (HPV). Of those, nearly half (44 per cent) were
infected with an HPV type that causes cancer.
Dr. Ann Burchell, the Project Coordinator and a former PhD student
and post-doctoral fellow with Dr. Franco at the Cancer Epidemiology
Unit, conducted the HITCH Cohort Study (HPV Infection and
Transmission in Couples through Heterosexual activity) to determine
the prevalence of HPV infections among recently formed couples.
This is the first large-scale study of HPV infection among couples
early in their sexual relationships when transmission is most
likely.
The results, published in the January 2010 issues of Epidemiology
and Sexually Transmitted Diseases, also indicate there is a high
probability of HPV transmission between partners. When one partner
had HPV, the researchers observed that in 42 per cent of couples,
the other partner also had the infection. Moreover, the researchers
found that the presence of HPV in one partner was the strongest
predictor of finding the same HPV type in the other partner. If one
partner was infected with HPV, the other partner's chance of also
being infected with the same HPV type increased over 50
times.
"These results build on our knowledge that HPV infection is very
common among young adults, and underline the importance of
prevention programs for HPV-associated diseases such as cervical
cancer screening and HPV vaccination," said Dr. Ann Burchell. "Our
results also suggest that HPV is an easy virus to get and to
transmit. Our estimates of the HPV transmission probability will be
of use to other researchers who use modeling to project the public
health and economic impact of HPV vaccination strategies."
HITCH Cohort Study participants are young women attending
university or college/CEGEP in Montreal, Quebec, and their male
partners. New couples are defined as those who have been together
for six months or less. Participants fill out questionnaires in
which they answer questions about their sexual history and they
also provide genital specimens for laboratory testing for the
presence of HPV infection. Recruitment for the study is
continuing.
"Our study is the first to investigate HPV transmission in a large
number of new couples among young adults," says Dr. François
Coutlée, a professor at the Université de Montréal Department of
Microbiology and Immunology and researcher at the Centre
Hospitalier de l'Université de Montréal where the HPV tests were
analyzed. "The results suggest that many HPV transmissions occur at
the start of new relationships, which reinforces the need for
prevention."
HPV is sexually transmitted and causes cervical cancer as well as
other cancers, including those of the vulva, vagina, anus, and
penis. Although HPV viruses are very common - more than 70 per cent
of women and men will have this type of infection at some point -
the vast majority of infections are asymptomatic and last no more
than one or two years. Fewer than 1 per cent of women who have HPV
will get cervical cancer.
The Canadian Institutes for Health Research provided support for
this study and for Dr. Franco's research program on HPV and
cervical cancer, with supplementary and unconditional funding
support by Merck-Frosst Canada Ltd. and Merck & Co. Ltd. Dr.
Burchell was supported by a research studentship from the Canadian
Cancer Society Research Institute and by a Richard H. Tomlinson
doctoral fellowship to ÎÛÎÛ²ÝÝ®ÊÓƵ University.
On the Web:
For more information, please visit: www.mcgill.ca/hitchcohort