Encephalomyocarditis Virus in Non-Domesticated Species

Abstract

Encephalomyocarditis virus (EMCV) causes sporadic and epizootic outbreaks among various domesticated and non-domesticated animal species worldwide. Although outbreaks are mostly reported in domestic pigs, mortality is reported in elephants, ungulates, nonhuman primates (NHPs), and rodents. Rats of the genus Rattus serve as primary reservoirs and vectors, but alternative infection routes have been proposed. Clinical disease is characterized by acute heart failure in most taxonomic groups, often culminating in rapid death. Due to the rapid progression of the disease, diagnostic confirmation is most commonly obtained postmortem. Pathological examination reveals interstitial lymphohistiocytic myocarditis and multiorgan congestion in most cases. EMCV is often demonstrated with RT-PCR or virus isolation techniques, but other methods, e.g., serology and immunohistochemistry, are available. The rapid progression of EMCV precludes effective therapeutic intervention, though agents such as interferon, verapamil, and curcumol have shown potential efficacy. Preventative strategies are crucial, emphasizing biosecurity measures to mitigate rodent contamination of feed and water. Inactivated vaccines have demonstrated protective efficacy in experimental models involving mice, pigs, and elephants, with analogous immunogenic responses observed in various zoological species. Live attenuated vaccines have conferred protection in pigs and NHPs, albeit with variable seroconversion rates in different species.

Keywords: EMCV; biosecurity; diagnosis; myocarditis; pathology; transmission; vaccination; virus; wildlife; zoo.