Infant Pertussis and Household Transmission in Korea

Kwon, Hyo Jin; Yum, Sook Kyung; Choi, Ui Yoon; Lee, Soo Young; Kim, Jong Hyun; Kang, Jin Han

The epidemiological characteristics of pertussis can vary depending on the definition of case, diagnostic method of confirmed case, national reporting system, network organization for epidemiological investigation, and the local vaccination schedule. National immunization program (NIP) of Korea consists of three primary series of diphtheria-tetanus-acellular pertussis vaccine (DTaP) at 2, 4, and 6 months, followed by a first booster at 15-18 months and a second booster between 4 and 6 yr of age. Recently, a tetanus toxoid, reduced diphtheria and acellular pertussis (Tdap) booster vaccine in adolescents aged 11-12 yr is added to Korean NIP in 2012. The vaccination rate of primary DTaP continues to be approximately 94% (12, 13) , and there is a mandatory notification system in Korea. An annual average of about 11.5 cases of pertussis has been reported to the Korea Center for Disease Control and Prevention (KCDC), however, the reported cases of pertussis have increased since the 2000s. In addition, the KCDC reported that the incidence of pertussis was markedly increased (more than about 5.5 times) in 2009, compared to the previous (14) . Also, the incidence of pertussis in 2011 was more than two times compared with the incidence in 2009 (15) . We may predict the substantial outbreak in the future in our country.