<p>This was a laboratory-confirmed pertussis outbreak, which may have occurred primarily due to low DTaP-IPV-Hib-HepB (diphtheria-tetanus-acellular pertussis-injectable polio-Haemophilus influenza b-Hepatitis B vaccine) vaccination coverage. The outbreak primarily affected children aged under 3 years. We recommend vaccination activities in the sub-district and awareness in the community to limit disease transmission.</p>