Abstract
I would like to congratulate Dr Masek-Hammerman and her colleagues for the excellent article on encephalomyocarditis virus (EMCV) in a group of rhesus monkeys at the Caribbean Primate Research Center’s Sabana Seca Field Station. However, this epizootic was not limited to a group but rather distributed randomly throughout the facility that houses both conventional and specific pathogen-free (SPF) rhesus. It was not clear if EMCV affected both colonies. It might be important to determine if SPF rhesus are more or less susceptible to EMCV.
Unfortunately, the authors failed to note or discuss a suspected major outbreak of EMCV in New World monkeys housed outdoors at the same facility in the late 1970s. 1 Due to the abundant feral rat population, peracute clinical course, and gross and histologic lesions, this epizootic was attributed to EMCV. Although rhesus at the facility were not acutely affected (lack of sudden death or pulmonary edema), gross and histologic lesions of myocarditis, similar to those shown in Figs. 1 and 3 of Masek-Hammerman et al, were common findings during the 1970s and 1980s. Due to the lack of sophisticated diagnostic techniques available at the time, there was no definitive diagnosis. Recent attempts to recover sufficient DNA from histologic slides for polymerase chain reaction were not successful.
I hope that this comment helps fill a historical gap in the accounts of EMCV (or suspected EMCV) epizootics in primates reviewed in this latest, most detailed and excellent report.