Table 1.
Summary of clinical signs and fecal viral RNA shedding in conventional weaned and feeder pigs, and boars and sows experimentally infected with different genogroups of porcine epidemic diarrhea virus (PEDV) strains via oral inoculation, or direct or indirect aerosol contact.
| Pig | Age (days or years) at inoculation or exposure | PEDV strain and inoculum dose | Infection or exposure route | Onset of diarrhea (PID)* | Duration of diarrhea (PID) | Onset of fecal viral RNA shedding (PID) | Duration of fecal viral RNA shedding | Peak viral RNA titers in feces or rectal swab fluids | Reference |
|---|---|---|---|---|---|---|---|---|---|
| Weaned | 21 days | US non-S INDEL, USA/Iowa/18984/2013, 1 mL of 1 × 103 PFU/mL* | Oral | PID 2 in 8/32 pigs (25 %) | PID 2−7 | PID 1 | Up to PID 24 | 4 × 104 PFU/mL at PID 4 | Madson et al., 2014 |
| Weaned | 21 days | US non-S INDEL, USA/IN19338/2013, 10 mL of 5.6, 56, or 560 TCID50/mL* | Oral | PID 2 in 1/6 pigs (16.7 %) | PID 2−7 | PID 2 | Up to PID 21 | Approximately 5−7.5 log10 RNA copies/mL at PID 5−6 | Thomas et al., 2015a |
| Weaned | 28 days | US non-S INDEL, USA/2014/Iowa, jejunal homogenate from infected pigs, 5 mL of 108 RNA copies/mL | Oral | PID 1 (2/2; 100 %) | NR¶ (but with sporadic vomiting at PID 1−31 and lethargy at PID 2) | PID 1 | Up to PID 21 | 11.5 log10 RNA copies/mL at PID 2−3 | Gallien et al., 2018a |
| Direct contact | PID 2 (6/8; 75 %) | PID 1−2 | Up to PID 42 | 11.1−11.4 log10 RNA copies/mL at PID 2−5 | |||||
| Indirect aerosol contact | PID 2 (8/10; 80 %) | NR (but with sporadic vomiting at PID 11−46) | PID 2 | Up to PID 49 | 10.5−12.2 log10 RNA copies/mL at PID 2−6 | ||||
| European S INDEL, FR/001/2014, jejunal homogenate from infected pigs, 5 mL of 108 RNA copies/mL | Oral | PID 4 | PID 4−25 (with sporadic vomiting and lethargy) | PID 2 | Up to PID 21 | 9.7−10.2 log10 RNA copies/mL at PID 4−6 | |||
| Direct contact | PID 4 | PID 4−14 | Up to PID 49 | 6.6−9.3 log10 RNA copies/mL at PID 6−21 | |||||
| Indirect aerosol contact | No clinical signs in 10 pigs (0/10) | No clinical signs | No fecal shedding | No fecal shedding | No fecal shedding | ||||
| Weaned to feeder | 28 days | US non-S INDEL, USA/KS/2013, 5 mL of 1.42 × 105 TCID50/mL | Oral | PID 3 | PID 3−8 | PID 2 | Up to PID 28 (1/12 pigs) | Titers not determined, but lowest Ct values in fecal and nasal swabs at PID 5−6 | Niederwerder et al., 2016 |
| Direct contact | PID 3 | PID 3−8 | PID 3 (with nasal shedding at PID 2) | Up to PID 21 (2/5 pigs) | |||||
| Indirect aerosol contact | No clinical signs in 5 pigs (0/5) | No clinical signs | No fecal shedding | No fecal shedding | No fecal shedding | ||||
| Weaned to feeder | 35 days (5 weeks) | US non-S INDEL, jejunal homogenate from a pig in Iowa | Oral | PID 4 | NR | PID 1−2 | Up to PID 18 | Titers not determined, but lowest Ct values at PID 2−6 | Lohse et al., 2017 |
| European, classical S INDEL, cell culture-grown Br1/87, 2 mL of 1 × 106.8 TCID50/mL | Oral | PID 4 | NR | PID 2−3 | Up to PID 18 | Titers not determined, but lowest Ct values at PID 3−8 | |||
| Feeder vs. nursing | 56 days (8 weeks) vs. 10 days | US non-S INDEL, USA/Colorado/2013, 10 mL of 9 × 104 PFU/mL | Oral in feeder pigs | PID 2 in 3 of 40 pigs (7.5 %) | NR | PID 1 in 9 of 48 pigs (18.7 %) | At least up to PID 14 in 9/20 pigs (45.0 %) | NR | Gerber et al., 2016 |
| Oral in nursing pigs | PID 1 in 2 of 43 pigs (4.6 %) | NR | PID 1 in 8 of 43 pigs (18.6 %) | At least up to PID 14 in 20/33 pigs (60.6%) | NR | ||||
| Boars | 1.5−2.5 years | US non-S INDEL, USA/2014/Iowa, jejunal homogenate from infected pigs, 5 mL | Oral | PID 2 | PID 2−5 and PID 25−28 (with vomiting at PID 2 and 11) | PID 2 | Up to PID 21−28 | 6.8 × 108 to 5.7 × 109 RNA copies/mL at PID 3−4 | Gallien et al., 2018b |
| Sows | Multiparous sows | European S INDEL, German cell culture-grown strain, 6 mL of 3.16 × 105 TCID50/mL | Oral | No diarrhea | No diarrhea (but with slight depression in 2/2 sows for 4 days) | PID 4−5 | Up to PID 10−14 | NR | Leidenberger et al., 2017 |
| European S INDEL, jejunal homogenate from a German pig | Oral | PID 1 (with vomiting) | NR | PID 4 | Up to PID 12−13 | NR | |||
| Gilts | Pregnant gilts§ | US non-S INDEL, PC22A, 1 × 105 PFU/pig | Oral | PID 2−4 | PID 2−6 | PID 2−4 | At least up to PID 14 | Approximately 8.5−10.0 log10 RNA copies/mL at PID 4−6 | Langel et al., 2019a |
Note no mortality of PEDV-infected nursing, weaned, or feeder pigs reported in these studies.
*
TCID50, 50 % tissue culture infectious dose; PFU, plaque forming unit; PID, post-inoculation day.
¶
NR, not reported.
§
Pregnant gilts were inoculated with PEDV at the early (day 19–22), middle (day 57–59), or late (day 96–97) gestation periods.