Almost 8,000 U.S. recipients of the vaccine used to protect against cervical cancer have reported adverse reactions, ranging from pain at the injection site to serious side-effects, says the U.S. Centers for Disease Control and Prevention.

A total of 7,802 people who received Gardasil, made by Merck and Co. Inc., have reported adverse events to the CDC's Vaccine Adverse Event Reporting System (VAERS) between June 8, 2006, and April 30, 2008. The United States distributed 2.2 million doses of the vaccine in 2006 and 11.3 million in 2007.

Of the people who reported adverse reactions, the most common side-effect was pain at the injection site, according to a recent CDC report.

Seven per cent had serious side-effects — "about half" the average of vaccines overall, according to the report. There were 31 reported cases of Guillain-Barré syndrome (GBS), a neurological condition that results in temporary but often total body paralysis, with 10 cases confirmed.

Fifteen deaths were also reported, with 10 of these containing the level of information required for further analysis, according to the CDC.

"After careful review of those reports, we could not establish the causal relationship between vaccination and death," reads the VAERS report.

The report notes that when Gardasil was being tested in the U.S. before being licensed, 10 individuals who were in the group that received the vaccine died, and seven in the placebo group died. None of these deaths were considered vaccine-related.

All Canadian provinces starting HPV vaccinations

Health Canada approved Gardasil on July 18, 2006. Since then, all 10 provinces have started or said they would be starting vaccination programs. Nova Scotia led the way, announcing in June 2007 that it would begin offering vaccinations to girls in Grade 7.

As of Jan. 8, 2008, the Public Health Agency of Canada had received a total of 145 reports of adverse events following vaccination with Gardasil, none of which were of death or Guillain-Barré syndrome, according to the agency.

"These reports are mostly of minor adverse events, including injection site reactions, which are consistent with the results reported by clinical trials conducted prior to the approval of the vaccine, and can be expected with the administration of any vaccine," reads PHAC's website.

The vaccine works by boosting the immune system so that it effectively fights off four types of human papillomavirus, the most prevalent STD in modern society. In North America, HPV is said to infect half of all sexually active women between 18 and 22.

It's estimated that about 1,300 women contract the sexually transmitted virus each year in Canada. About 400 women in Canada die of cervical cancer annually — making it the second most common type of cancer for women between the age of 20 and 44.