Seroepidemiology of Saffold Cardiovirus Type 2

To the Editor: Saffold virus (SAFV) is a new human virus belonging to the genus Cardiovirus of the family Picornaviridae (1-6). The virus has also been named human Theiler's-like cardiovirus (4). To date, 8 SAFV genotypes are known, based on molecular variation in the P1 region, which codes for the viral capsid (5). SAFVs are detected in respiratory and fecal samples from infants and children <6 years of age. The virus is generally detected at low frequency (0.5%-3%) in the general population, but in Afghanistan and Pakistan higher incidences have been reported (10%-12%) (5). Detection is mainly based on molecular techniques because virus isolation is cumbersome. Other than gastroenteritis, no clear disease manifestations are known (1-8), although recently, researchers in Japan have suggested that for a select group of children, SAFV infection may cause pharyngitis and tonsillitis (7). In rodents, however, cardioviruses are serious pathogens that can cause myocarditis, meningoencephalitis, and pancreatitis.