”Pink Eyes”: Confirmation of Pathogens and Investigation and Analysis of Molecular Epidemiology

Tsuey-Li Lin

2008 Vol.24 NO.4

Correspondence Author： Tsuey-Li Lin

Abstract：

An outbreak of “pink eyes” occurred in Taiwan in October 2007, starting in Keelung City and Yunlin County, followed by other areas in Taiwan. A total of 16,047 cases were reported as of October 19, 2007. Ninety-one cases had clinical samples taken. Isolation and identification of pathogens were done by Taiwan CDC. The 91 cases lived in Taipei City, Keelung City, Taipei County, Yunlin County, and Chiayi County. Male to female ratio was 1.1:1. The youngest case was 2-month-old, and the eldest was 86-years-old. Multiple methods were used in the lab for identification and confirmation of the pathogen. Coxsackievirus A24 variant (CA24v) was identified as the pathogen of this “pink eyes” outbreak, which should be called as acute hemorrhagic conjunctivitis (AHC). Molecular epidemiology analyses showed that the genotype of the pathogen was cluster 6 of genotype III, similar to the AHC strain isolated in Singapore in 2005. The strain appeared in Taiwan after 1985 in different years, and this outbreak was the first one in Keelung City after 1994, which also spread toward southern part of the island. The outbreak ended within a month. Health authorities had used multiple prevention strategies, including media advertisement, education in schools, cooperation of medical centers, and efforts of disease prevention personnel. Hand washing, stop sharing towels, decrease exposure in public areas including schools and offices by people having symptoms, and strengthening personal hygiene are effective ways to block or decrease transmission of the pathogen. In addition, the outbreak occurred close to fall, when outbreaks of enteroviruses are not as strong as in summer. From 1986 to 2003, lineages of CA24v had a close relationship to the time of outbreaks. Usually viruses were in the same lineages in two consecutive years. We should strengthen reporting and monitoring of “pink eyes” and its pathogens to prevent another outbreak.
Keywords: pink eyes, coxsacikevirus A24 variant (CA24v), acute hemorrhagic conjunctivitis (AHC), genotype