Government advisers in Germany are reviewing the programme there after leading scientists said the jab was failing to live up to expectations on the number of cervical cancer cases it might prevent. Now critics say Scottish health advisers, who gave the go-ahead for a 64 million immunisation programme involving thousands of schoolgirls, should review the evidence as well.
The HPV vaccine protects against two strains of the human papilloma virus, which are responsible for most cases of cervical cancer. About 100 Scottish women die of the sexually transmitted disease every year.
Germany's Robert Koch Institute, which makes recommendations on the public funding of vaccines, is reviewing its programme after 13 experts called for a reassessment of its HPV vaccination programme and an end to "misleading information" about the effectiveness of the jab.
The HPV vaccine is said to be effective in preventing the two strains of the virus that cause 70 per cent of cervical cancer cases, and scientists have assumed this means the vaccine can prevent 70 per cent of cases of cervical cancer.
But the German experts said the assumptions simply did not stand up to scrutiny, and that women remained at risk from other strains of the virus.
Studies of one vaccine brand, Gardasil, estimated it reduced the rate of pre-cancerous cells by only between 17 and 45 per cent. The scientists also warned that detailed data on Cervarix, which is the vaccine used in Scotland, was not being made available by its manufacturer.
Dr Ansgar Gerhardus, a public health expert from the University of Bielefeld in Germany, said: "The results of the studies clearly contradict many overly optimistic pronouncements. Women are entitled to be adequately informed."
A spokeswoman for the Robert Koch Institute said its vaccination committee was reviewing the situation, adding: "Because of the public discussion and some new reports and new statements from the 13 professors, the committee will publish a statement within the next few weeks."
Scottish Conservative health spokeswoman Mary Scanlon said: "Given this new research, it is now incumbent on the Scottish Government and the chief medical officer to review the vaccination programme to ensure that it lives up to the expectations of preventing cervical cancer."
A spokesman for GlaxoSmithKline, which makes Cervarix, was unable to provide figures on cases of pre-cancerous cells in women who have taken the vaccine, compared with those who have not.
He said: "The current scientific opinion is that an HPV vaccine such as Cervarix should improve the body's immune response to natural HPV infection, which is important as women remain vulnerable to HPV infection … throughout their sexually active life."
The Scottish Government said: "We believe Scotland's HPV immunisation programme is a major step forward in saving lives. The programme is based on advice from the Joint Committee on Vaccination and Immunisation.
"Should the JCVI's recommendation change, this would obviously be considered very carefully by ministers."