Affiliation: *National Institute of health, Department of Medical Sciences
**Bureau of Epidemiology, Department of Deseases Control. Tiwanond Road, Nonthaburi, Thailand
Source: Bulletin of the Department of Medical Sciences 2003; 46(1): 25 – 35
Vaccine – associated paralytic poliomyelitis (VAPP) is an adverse event of residual paralysis following the administrative of Oral Polio Vaccine (OPV). In USA, VAPP risk was 1 case per 2.5 million doses of OPV distributed in 1980 to 1989. In England and Wales, the risk of VAPP in 1985 to 1991 was 1 case per 1.4 million OPV doses administered. No study of VAPP has been done in Thailand. The purpose of this study is to investigate the epidemiological and virological data of VAPP case and to assess the risk of VAPP in Thailand. The process included the national acute flaccid paralysis (AFP) case surveillance, isolation of vaccine – related poliovirus in stool samples by WHO Polio Regional Reference Laboratory, case investigation by an epidemiologist and case reviewed by the National Expert Review Committee (NERC). There were 5 AFP cases in 2001 and 3 AFP cases in 2002, which had the vaccine – related poliovirus in the stool samples and had residual paralysis 60 days after onset. Nevertheless, none of them was considered as VAPP after reviewing by NERC. The conclusion of this study was no VAPP in Thailand during 2001 to 2002 and the VAPP risk was less than 1 case per 30 million OPV doses administered.