In an initial clinical trial in Australia, minor side-effects were reported by about half of the 240 people vaccinated, with these side-effects including tenderness and pain at the site of injection, headache, malaise, and muscle pain. Two people had more severe reactions, with a much longer spell of nausea, muscle pain and malaise that lasted several days. The authors stated that the frequency and severity of these side-effects were similar to those normally seen with seasonal influenza vaccines. A second trial involved 2,200 people ranging from 3 to 77 years of age. In this study no patients reported severe side-effects, with the most common reactions being pain at the injection site and fever, which occurred in 10-25% of people.