Update on Swine Enteric Coronavirus Disease in US

US - The number of pig farm samples that are confirmed positive for porcine epidemic diarrhoea virus (PEDV) in the last week was 58, two premises were confirmed with porcine deltacoronavirus (PDCoV) and one with the dual infection (PEDV and PDCoV).

20 March 2015

5 minute read

By: Jackie Linden

North America

For the latest week – 8 to 14 March – there were 58 new confirmed positive premises for PEDV and none presumed positive, according to the latest report from USDA APHIS made available by the American Association of Swine Veterinarians (AASV).

For the same period, two premises were confirmed positive for PDCoV but none was presumed positive, and there were also one confirmed dual infection (both PEDV and PDCoV) but none presumed positive.

The total numbers of premises with confirmed positive status for the current week are 1,042, 47 and 44 for PEDV, PDCoV and the dual infection, respectively.

Since 5 June, for PEDV, there have been 1,106 confirmed positive premises, 416 presumed positive and 52 previously positive premises that have attained negative status.

For PDCoV, the total for the same period are 53, 27 and five, respectively. For the dual infection, the totals are 46, 27 and one, respectively.

Month	Nursery	Wean to finish	Farrow to finish	Finisher	Sow/ breeding	Un- known
Table 1. Number of swine enteric coronavirus disease (SECD) confirmed and presumptive positive premises by month and production class (includes PEDV, PDCoV and dual infections; confirmed/presumptive)
Jun-14	18 / 11	30 / 16	15 / 8	22 / 28	47 / 45	14 / 52
Jul-14	25 / 12	36 / 8	6 / 5	20 / 13	33 / 12	15 / 33
Aug-14	15 / 8	17 / 6	2 / 5	25 / 10	10 / 6	10 / 22
Sep-14	17 / 3	21 / 5	2 / 2	30 / 8	31 / 7	6 / 14
Oct-14	2 / 4	24 / 5	2 / 0	33 / 15	6 / 2	11 / 8
Nov-14	6 / 1	15 / 3	1 / -	40 / 6	11 / 8	20 / 8
Dec-14	16 / 1	42 / 2	12 / 4	60 / 8	20 / 4	12 / 4
Jan-15	19 / 3	71 / 7	9 / 0	69 / 13	18 / 1	39 / 5
Feb-15	8 / 0	44 / 2	3 / 0	45 / 5	9 / 1	25 / 0
Total	132 / 48	318 / 59	54 / 25	358 / 110	195 / 93	148 / 135

	PEDV			PDCoV
Table 2. Biological accessions tested and number positive by month (since 5 June 2014)
Month	Tested	Positive	% positive	Tested	Positive	% positive
Total before 5 June 2014	21,128	6,976	33.0	2,172	260	12.0
Jun-14	2,768	407	14.7	824	80	9.7
Jul-14	3,555	410	11.5	1,195	46	3.8
Aug-14	3,095	312	10.1	1,193	18	1.5
Sep-14	3,143	261	8.3	1,338	11	0.8
Oct-14	3,304	299	9.0	1,899	19	1.0
Nov-14	2,505	305	12.2	1,555	30	1.9
Dec-14	3,237	446	13.8	1,982	50	2.5
Jan-15	3,089	500	16.2	1,845	44	2.4
Feb-15	2,978	461	15.5	1,799	49	2.7
Mar-15 to date	1,533	293	19.1	865	26	3.0
Total since Jun-14	29,215	3,692	12.6	14,521	371	2.6
Grand total	50,343	10,688	21.2	16,693	631	3.8

Figure 1. PED-positive biological accessions in the US, by week (since 5 June 2014)

Figure 2. PDCoV-positive biological accessions in the US, by week (since 5 June 2014)

Location of Positive Premises

PEDV

There are currently 31 states with at least one confirmed positive case of PEDV. Georgia reported its first positive finding in the first week of March and has now reported six cases.

For the current week (8 March), there were 158 PEDV-positive laboratory accessions, bringing the total since 5 June 2014 to 3,692. Iowa reported 54 of these new cases, North Carolina 31, Missouri 13 and Illinois 11.

Also reporting positive results in this most recent week were Indiana, Kansas, Michigan, Minnesota, Nebraska, Ohio, Oklahoma, South Dakota, Texas, Utah and "unknown".

Figure 3. PEDV: Cumulative confirmed and presumptive PEDV-positive premises since 5 June 2014

PDCoV

There are currently 19 states with at least one confirmed positive case of PDCoV.

For the current week (8 March), there were 14 PDCoV-positive laboratory accessions, bringing the total since 5 June 2014 to 368. There were four positive premises in Illinois, three each in Indiana and North Carolina, two in Michigan and one each in Iowa and Minnesota.

Figure 4. PDCoV: Cumulative confirmed and presumptive PDCoV-positive premises since 5 June 2014

Dual infection with PEDV and PDCoV

There are currently 14 states with one or more confirmed positive cases of the dual infection with both PEDV and PDCoV.

Most-affected states with the dual infection are Iowa and Minnesota, with 18 and nine confirmed positive results, respectively. APHIS has not updated the table giving the location of the new positive results this week.