EM, electron microscopy; M, membrane; pan-CoV RT-PCR, pan-coronavirus reverse transcription PCR; PEDV, porcine epidemic diarrhea virus; PRCV, porcine respiratory coronavirus; RdRp, RNA-dependent RNA polymerase; S1, spike; TGEV, transmissible gastroenteritis
virus; +, positive; -, negative; NA, not tested or sequenced.
Site-specific alteration of transmissible gastroenteritis
virus spike protein results in markedly reduced pathogenicity.
None of the samples tested were positive for transmissible gastroenteritis
For the pig-passaged PC21A strain, RT-PCR/PCR results were negative for transmissible gastroenteritis
virus/porcine respiratory coronavirus (7), rotavirus groups A-C (8), caliciviruses (13,14), astroviruses (15), circoviruses, enterovirus, kobuvirus, and bocavirus.
These piglets were shown by serologic analysis to be negative for antibodies against PEDV, porcine reproductive and respiratory syndrome virus, porcine transmissible gastroenteritis
virus, and pseudorabies virus.
In the China outbreak, PEDV caused severe diarrheal disease in piglets; heavy economic losses in many provinces resulted, despite use of commercial vaccines (inactivated transmissible gastroenteritis
[TGEV H] and porcine epidemic diarrhea [CV777]).
porcine transmissible gastroenteritis
virus [TGEV] and its derivative porcine respiratory coronavirus [PRCoV], feline coronaviruses [FCoVs], and canine coronaviruses [CCoVs]) (2).
Similarly, key amino acid changes in the porcine coronavirus spike gene lead to increased virulence in the coronavirus transmissible gastroenteritis
virus, a fatal disease causing high rates of illness and death in young pigs (20-22).
Including chapters on transmissible gastroenteritis
virus and porcine respiratory coronavirus would also have been beneficial.
Most widely studied and of common occurrence are coronaviruses reported in chickens (infectious bronchitis virus), turkeys (turkey enteric coronaviruses), cats (feline infectious peritonitis virus and feline enteric coronavirus), dogs (canine enteric coronaviruses), swine (porcine hemagglutinating encephalomyelitis virus, porcine transmissible gastroenteritis
virus, and porcine respiratory coronavirus), cattle (bovine enteric and respiratory coronaviruses), mice (Murine hepatitis virus), rats (sialodacyradenitis virus), rabbits (rabbit coronavirus), and humans (respiratory and enteric coronaviruses) (9).