Human papillomavirus

A lot of new data on the immunogenicity, efficacy and effectiveness of fewer than three doses of HPV vaccine have become available since the publication of the CIQ report on the 2012 knowledge update. The two-dose schedule has become a standard that is widely accepted around the world. Such schedules are currently in use in more than half (48/82) of the countries offering HPV vaccination programs. The same schedule has been approved and recommended by the World Health Organization (W HO) and the Global Alliance for Vaccines and Immunization (GAVI).

A number of clinical and ecological studies have even come up with some interesting and promising results in terms of the immunogenicity and efficacy of single-dose HPV vaccination. Immunogenicity studies have shown that sero-conversion rates after a single dose of vaccine are often in excess of 95%, although with considerably lower geometric mean titers (GMTs) than those observed after two or three doses. However, antibody titers…

In 2007, the Comité sur l’immunisation du Québec (CIQ) recommended an extended schedule exclusively for immunization against the human papilloma virus (HPV) starting in grade 4 (0, 6, 60 months); the committee also stated that the third dose should be administered “if judged necessary.” Since the introduction of the Québec HPV immunization program in 2008, similar programs (two doses administered six months apart and a possible third dose if necessary) have been introduced in Mexico and British Columbia. In 2012, the committee of immunization experts in Switzerland recommended for pre-adolescents a schedule comprising two doses administered six months apart. In recent years, a number of studies have been published on the immunogenicity of HPV vaccines administered according to alternative schedules and other studies are presently underway to document the efficacy of one, two, or three doses administered at different intervals.

The present advisory report, which is based…

The human papillomavirus (HPV) belongs to the Papillomaviridae family, which includes at least 100 genotypes affecting the skin and mucous membranes. Of these, about 40 affect the anogenital area in particular, and approximately 15 are oncogenic. Genotypes 16 and 18 are responsible for 70-76% of cervical cancer cases worldwide. Genotypes 6 and 11 are non-oncogenic but are responsible for most cases of condyloma (anogenital warts [AGW]).

HPV prevalence and incidence data are estimated on the basis of epidemiological studies and are better documented in women than men. HPV prevalence varies widely by geographic region, age, the selected subpopulation and HPV detection method. In women, the overall age-adjusted prevalence of genital infections worldwide is estimated at 11.7%. It peaks in young women aged 20-24 and declines subsequently with age. The risk of acquiring HPV infection is particularly high in the first few years after sexual activity begins. Ac…

In October 2007, the Comité sur l'immunisation du Québec (CIQ) tabled a report entitled “Prévention par la vaccination des maladies attribuables aux virus du papillome humain au Québec” [Prevention of diseases caused by human papillomaviruses through vaccination]. At the time that report was being drafted, only one vaccine – Gardasil – was authorized for sale in Canada. The report did not directly compare the Gardasil and Cervarix vaccines.

Given the likelihood that the Cervarix vaccine would be approved, the Direction générale de la santé publique (MSSS) submitted a request to the Institut national de santé publique du Québec (INSPQ) on December 19, 2007, asking the latter to produce an advice with respect to the following question: “Do the two HPV vaccines have an equivalent ability to achieve the stated goal of the immunization program, which is to reduce the incidence of and mortality associated with cervical cancer?”

This document seeks to compare the performanc…

The problem of the prevention of diseases attributable to the human papilloma virus (virus du papillome humain) (HPV) extends beyond the field of infectious diseases traditionally prevented by vaccination. This is why the CIQ has followed a different procedure for the preparation of this report by working with a large group of experts, notably from gynaecologists involved with the fight against cancer and from sexually transmitted infectious diseases areas.

The synthesis of facts was done by a writing committee made up of 4 people, following a model developed by Erickson and De Wals (Vaccine, 2005) which is currently the benchmark in this area. This synthesis encompasses all the information available up to August 15, 2007. A broader meeting of the CIQ, with more than 20 experts participating from those areas affected by diseases attributable to HPV, occurred on May 31 and June 1, 2007 in Longueuil. The recommendations outlined in this report, were developed during this meeti…

Human papillomavirus (HPV) infection is recognized as one of the most common – if not the most common – sexually transmitted infections. The association between HPV and cervical cancer has also been recognized, while more recently it has been associated with some other types of cancer, primarily those in the genital region.

Our understanding of HPV has advanced considerably in the past decade. In fact, we now speak of human papillomavirus infections since there are roughly 100 viruses of varying pathogenecity. New technologies used for detection are being developed with increasing speed, new treatments are available and research on therapeutic or preventive vaccines continues to show promise.

Nonetheless, there is no doubt that HPV infections are a major public health problem.

Recognizing the magnitude of a public health problem is the first step in prevention. However, it is important to fully understand the various components of this problem in order to ide…