Emerging outbreaks associated with equine coronavirus in adult horses

Abstract

The purpose of this study was to describe clinical, hematological and fecal PCR results from 161 horses involved in outbreaks associated with ECoV. The outbreaks happened at four separate boarding facilities between November 2011 and April 2012 in the States of CA, TX, WI and MA. Following the molecular detection of ECoV in the feces from the initial index cases, the remaining herdmates were closely observed for the development of clinical signs. Fecal samples were collected from sick and healthy horses for the PCR detection of ECoV. All four outbreaks involved primarily adult horses. Fifty-nine horses developed clinical signs with 12-16 sick horses per outbreak. The main clinical signs reported were anorexia, lethargy and fever. Four horses from 3 different outbreaks were euthanized or died due to rapid progression of clinical signs. The cause of death could not be determined with necropsy evaluation in 2 horses, while septicemia secondary to gastrointestinal translocation was suspected in 2 horses. Blood work was available from 10 horses with clinical disease and common hematological abnormalities were leucopenia due to neutropenia and/or lymphopenia. Feces were available for ECoV testing by real-time PCR from 44 and 96 sick and healthy horses, respectively. 38/44 (86%) horses with abnormal clinical signs tested PCR positive for ECoV, while 89/96 (93%) healthy horses tested PCR negative for ECoV. The overall agreement between clinical status and PCR detection of ECoV was 91%. The study results suggest that ECoV is associated with self-limiting clinical and hematological abnormalities in adult horses.

Application of Transmission Electron Microscopy Techniques in the Veterinary Diagnosis of Viral Gastroenteritis in Livestock Animals

“…Respiratory problems, profuse aqueous diarrhea greenish to yellowish of putrid odor and discrete algia abdominal can also been observed [136,141,[144][145][146][147]. It is transmitted by the fecal-oral route, and signs tend to resolve in 1-4 days, although animals can continue shedding for several weeks [147].…”

“…It is transmitted by the fecal-oral route, and signs tend to resolve in 1-4 days, although animals can continue shedding for several weeks [147]. It is suggested that ECoV may spread among horses when they are stabled together or during transport [148,149].…”

“…The virus has been diagnosed more frequently in adult animals over 2 years of age [146,147,150]. However, outbreaks have been reported in foals from 5 days to 4 months of age [139,144,145,151] and in both adults and young animals [141].…”

“…Morbidity ranges from about 20-57%, and mortality is typically rare [147]; however, a high mortality rate has been described in foals [152].…”

Evolving views on enteric viral infections of equines: an appraisal of key pathogens

“…Molecular techniques like nested PCR and quantitative PCR have been actively used in the diagnosis of ECoV (Guy et al, 2000;Slovis et al, 2010). During early stages of infection highly sensitive technique like real-time RT-PCR has been used (Pusterla et al, 2013;Miszczak et al, 2014). In 2015, a RT-LAMP was also developed for the isothermal detection of ECoV which can be economical in comparison to other diagnostic tests (Nemoto et al, 2015a).…”