Pain at the injection site was the most frequently reported local symptom, reported by 87.1%–93.2% of vaccinees in each group (Table 4). Grade 3 local symptoms (see Table 4 footnote for grade 3 definitions) were reported by not more than five participants in any group. One participant (dTpa-0.133 group) reported a large swelling reaction with onset 3 days after the booster dose. The swelling was confined to the injection site and resolved after 2 days.