Prevalence of coxsackievirus A5, A6, and A10 in patients with herpangina in Aichi Prefecture, 2005.

*Corresponding author: Mailing address: Department of Microbiology, Aichi Prefectural Institute of Public Health, 7-6, Nagare, Tsujimachi, Kita-ku, Nagoya, Aichi 462-8576, Japan. Tel: +81-52-910-5674, Fax: +81-52-913-3641, E-mail: tyamashita@ hi-ho.ne.jp Herpangina is caused primarily by coxsackievirus A (CVA) 1, 2, 3, 4, 5 (CV-A5), 6 (CV-A6), 8, 10 (CV-A10), and 22 (1) in the genus Enterovirus of the family Picornaviridae. The illness is characterized by an acute onset of fever and sore throat (2). In Aichi Prefecture, located near the center of Japan’s main island of Honshu, the number of case reports of herpangina increased from the 23rd week of 2005 and resulted in occurrence exceeding 12 cases per sentinel in the 27th week of 2005 (a diagram is available at http://www. pref.aichi.jp/eiseiken/herpan_graph.html). The number was twice as great as the average of the last 5 years. We detected CV-A5, -A6, and -A10 from these patients. Feces and/or throat swabs were collected from 64 herpangina patients who visited 9 pediatric clinics in Aichi Prefecture between April and July 2005. Their ages ranged from 4 months to 7 years. Their samples were suspended in Veal infusion broth and centrifuged at 10,000×g for 20 min. The supernatants were inoculated onto RD cells and used for RT-PCR, as previously described (3). Briefly, the supernatants were mixed with TRIzol and followed by isopropanol precipitation. The pellet was suspended in RNase-free water. RT-PCR was performed using Access Quick RT-PCR System (Promega, Madison, Wis., USA). Primers OL68-1(+) and MD91(-), designed by Olive et al. (4) and Rotbart et al. (5), were used for RT-PCR. Primers OL68-1(+) and EVP4(-), designed by Rotbart et al. (5), were used for the nested PCR. Following the PCR, amplified products were purified and introduced into a pGEM-T vector (Promega). The DNA Laboratory and Epidemiology Communications