HPV vax does not increase risk of seizures or anaphylaxis: study

A US post-licensure safety study of the quadrivalent HPV vaccine has found no evidence to support concerns of an increased risk of seizures or anaphylaxis.

A 2008 Australian study finding an increased rate of anaphylaxis in the school-based Gardasil vaccination program may have included imprecise estimates, researchers said.

Their analysis of US data on 600,558 doses of Gardasil showed no increased risk of Guillain-Barré syndrome, stroke, appendicitis or syncope.

However, it did show an elevated – although non-statistically significant – risk of VTE in younger women. All five confirmed VTE cases had other risk factors for VTE but the association “deserves additional study”, the researchers said.

Vaccine 2011; online 8 Sept