Background: In April 2008, the first case of pertussis since 1998 was diagnosed in the Free State province. The outbreak that occurred over a 12-month period is described in this article.

Method: This is a case series of 18 children diagnosed with pertussis in Bloemfontein, Free State province, between April 2008 and March 2009. The clinical diagnosis was confirmed by means of a Bordetella polymerase chain reaction test done on a nasal swab. Data were collected from every child with a confirmed diagnosis of pertussis.

Results: Eighteen cases of pertussis were diagnosed in the 12-month period; 15 in the public sector and three in the private sector. A peak of cases was observed in the autumn and early winter months. Twelve infants were under six months of age and were thus regarded as “pre-vaccinated”. Fourteen children required admission to hospital, of whom five required intensive care. No deaths occurred. The cost of managing these children was high.

Conclusions: Pertussis is not commonly diagnosed in South Africa. Young children are worst affected by the disease. Ongoing surveillance is needed. A vaccination plan to prevent pertussis in South Africa requires consideration.