Summary

• Our last review of HPV vaccine safety in 2011 concluded that most adverse effects appeared to be mild and transient.
  
  
• In late 2014, we again reviewed available data on the adverse effects of the two available HPV vaccines, using the standard Prescrire methodology.
   
• The adverse effects of HPV vaccines have been carefully examined by several drug regulatory agencies. Tens of thousands of reports have been collected and analysed. Along with epidemiological studies, the results suggest that serious adverse events are unlikely to be due to the vaccines, apart from syncope and very rare anaphylactic reactions, the incidence of which similar to that observed with other vaccines.
   
• New data confirm that there are no safety signals with the HPV 6,11,16,18 vaccine. The known adverse effects of this vaccine are no reason to limit its use. In late 2014, the available data point to partial efficacy in preventing cervical dysplasia due to the targeted HPV genotypes, but the impact on invasive cervical cancer will not be known for several years.
   
• Fewer data are available for the HPV 16,18 vaccine and this, along with presence of a lipid adjuvant, warrants rigorous pharmacovigilance. It also means that the HPV 6,11,16,18 vaccine should be chosen when immunisation against papillomavirus is considered.
   
• Even if it turns out that HPV vaccines reduce the incidence of invasive cervical cancer, it should be remembered vaccination cannot replace screening, which remains the cornerstone of cervical cancer prevention.
  
  
• Girls and their parents should be informed that vaccination is only one element in the fight against cervical cancer and that screening is the most effective method for reducing the incidence of cervical cancer. This would be easier if nationwide screening programmes were implemented.

©Prescrire 1 May 2015

"Human papillomavirus vaccines: 2014 safety review" Prescrire Int 2015; 24 (160): 122-129. (Pdf, subscribers only)