Aminopeptidase N Knockout Pigs Are Not Resistant to Porcine Epidemic Diarrhea Virus Infection

Dear Editor,Porcine epidemic diarrhea virus(PEDV)is the etiologic agent of porcine epidemic diarrhea(PED),which is an acute,highly contagious,and devastating enteric viral disease in pigs(Lee 2015).PEDV is a coronavirus that mainly infects and replicates in villous enterocytes of the small intestine in pigs(Li et al.2016).PEDV can infect pigs in all age groups,with symptoms of varying degrees,such as watery diarrhea,dehydration,vomiting,and growth retardation.Particularly,PEDV is most detrimental to neonatal pigs,and the mortality rates can reach 100%(Stevenson et al.2013;Lee 2015).PEDV can persist in pigs after infection and become endemic in the farm.PED outbreaks occur periodically in many countries and have resulted in great economic losses to the pig industry worldwide.Effective infection prevention and control of PEDV can only be achieved through the use of vaccines.