swine acute diarrhea syndrome coronavirus swine acute diarrhea syndrome coronavirus swine acute diarrhea syndrome coronavirus (sads-cov) is a coronavirus related to rhinolophus bat coronavirus hku2. it is transmitted through the feces of horseshoe bats to pigs. piglets less than 5 days old die with a probability of up to 90%. swine acute diarrhea syndrome coronavirus virus classification (unranked): virus realm: riboviria kingdom: orthornavirae phylum: pisuviricota class: pisoniviricetes order: nidovirales family: coronaviridae genus: alphacoronavirus subgenus: rhinacovirus virus: swine acute diarrhea syndrome coronavirus the first outbreak appeared in 2017, where it caused the death of more than 24,000 piglets on 4 farms. in 2018 and 2019, the virus re-emerged in china, but there were not large-scale losses. this weak re-emergence is curious, and is reminiscent of how sars emerged in 2003 and then disappeared. during in vitro testing, human and monkey cell lines exposed to sads-cov became infected, suggesting that sads-cov may pose a risk to human health. the sads-cov sampled from one of the first infected pig farms was found to be 95% genetically identical to one collected from horseshoe bats (rhinolophus), "indicating the bat origin of the pig virus".