A study of the side effects of Pandemrix influenza (H1N1) vaccine after whole-crew vaccination on board a Norwegian naval vessel

Abstract

Background: The frigate His Norwegian Majesty’s ship (HNoMS) Fridtjof Nansen was participating in operations in the Gulf of Aden in support of the EU mission tasked with protecting vessels from the threat of piracy. The crew was therefore prioritized and given the first batch of Influenza A (H1N1) vaccine (Pandemrix®). Objectives: To investigate the type, frequency, and intensity of side effects after whole-crew vaccination with Pandemrix vaccine in healthy subjects in a controlled environment. Material and methods. A hundred and thirty-three members of the crew were vaccinated, and then they participated in the study. The side effects of the vaccination were evaluated through a survey. Results: Seventy-five per cent of the vaccinated sailors reported adverse reactions to the vaccine, with 9% not being able to perform their daily duties for one day. Muscle pain, headaches, malaise, and fatigue were the most frequent symptoms reported. Conclusions: The vaccination program using Pandemrix H1N1 vaccine resulted in a high rate of side effects, which were generally mild and resolved within a few days. No serious lasting side effects of the vaccination were reported or registered. The adverse effects of the vaccination did not affect the operational capacity of the vessel.