About 10 percent of those harmed by the cervical cancer vaccines Cervarix and Gardasil haven’t recovered yet, the health ministry has learned, adding that the June 2013 moratorium on promoting the drugs will stay in place.
According to a ministry survey of 1,739 patients, 186 were still experiencing side effects including headaches, fatigue and muscle weakness since being vaccinated, ministry officials said. Some of them lost their ability to walk.
In 135 of the cases, the problems are so severe they interfere with daily activities, including school and work.
Health minister Yasuhisa Shiozaki said Friday that the ministry is planning to begin research on why the side effects occur and potential treatments for them.
NHK reported that the ministry will also begin screening applications filed for medical benefits, but only in cases where a clear link exists or cannot be denied.
The drugs in question are Cervarix, made by GlaxoSmithKlein PLC, and Gardasil, a Merck Sharp & Dohme Corp. product. They inoculate against the human papillomavirus, which is believed to be the main cause of cervical cancer.
Vaccination is believed to have a 50 to 70 percent success rate against the virus. It requires three injections into the upper arm or thigh within six months.
Some 3.38 million people were vaccinated between December 2009, when the drugs were launched, and November 2014.
According to the survey, 2,584, or 0.08 percent, of the recipients suffered side effects, a rate higher than for the diphtheria, tetanus, pertussis and polio combination vaccines or Japanese encephalitis vaccines.
Of those harmed, 1,550 recovered to the extent that hospital visits were not needed, with 1,297 recovering within a week. In 114 recipients, medication or physical therapy proved effective. What happened to the other victims is unclear.
In April 2013, the ministry began recommending that girls aged 12 to 16 get vaccinated to stem a rise in cervical cancer. The surge in side effects brought those recommendations to a halt in June 2013.
In August 2013, a nationwide group representing victims of the vaccines and their parents called on the ministry to make stronger efforts to identify the cause of the side effects and to find a remedy.
In January 2014, the panel came to the conclusion that the symptoms are reactions to the pain of the vaccination itself, after examining 176 sufferers who complained of full-body pain or motor impairment.
The ministry conducted the followup survey after being criticized by patients’ groups, who called for additional research.