On 11 June 2009, an Influenza A (H1N1) pandemic was declared by the World Health Organization (WHO). The Major Medical Incident Regional Command and Control Protocol in the County Council of Östergötland, Sweden was activated. After vaccinations were competed, it was decided that the operation should be evaluated in a retrospective study. This study aims to increase knowledge regarding regional management of a pandemic flu.

All protocols from regional command meetings were studied together with central data regarding, logistics, vaccination site reports, incident reports, and all written correspondence between involved departments. Information from results of a questionnaire that was distributed to all vaccination site managers were summarized and studied. In addition, an interview was performed with the chief of medical operations.

Out of the approximately 426,000 inhabitants of the county, a total of 224,780 (53%) were vaccinated during a five and a half month period. The mean pace was 1,246 vaccinated per day (range 0–9643). Regional command had 41 recorded meetings resulting in a collected number of about 740 working hours. Three hundred sixty-six employees were involved in the vaccination, working 38,741 hours. Twenty-eight safety and 52 security incidents were reported. Uncertainty about vaccine delivery and keeping the public's interest were reported to be of concern for the management.

Even with the large scale of the operation, there were only a few security and safety issues. Although the goal of vaccinating 75–80% of the inhabitants was not reached, it could be assumed that the pandemic was dampened. Given the public's high initial interest, it could be considered that vaccination should not start until a large number of doses have been delivered.

The medical incident command structure and protocol successfully can be adapted to a mass vaccination event. Information from the Östergötland County Council operation yielded significant experience for future mass vaccinations.