Efficacy evaluation of regular vaccination in a PED-positive farm with a new high titer PEDv inactivated vaccine (newPED-X)

A new strain of Porcine Epidemic Diarrhea virus (PEDv) occurred in the Republic of Korea in November 2013 and continues to impact the swine industry up to now. The new strain was sequenced and the results showed that the spike protein gene of this newly prevalent PEDv is 99.64%~99.81% homologous to the PEDv isolated in USA from 2013 to 2014.

CAVAC acquired ISU46065IA13 strain (genotype 2a), a field isolate by Iowa State University, USA, and developed a new high titer PEDv inactivated vaccine (newPED-X). Upon development of the vaccine, CAVAC applied this vaccine regularly to a farm suffering from PEDv and monitored the changes in the farm’s status.

The farm has 2,300 sows and operates a one-site rearing system. PED first occurred in this farm in February 2014 and as treatment, feedback program was implemented. However, the condition of weaned piglets deteriorated due to persistent diarrhea of suckling piglets in the farrowing house and the weight decline of weaning piglets. In order to normalize the farm, they started to vaccinate sows with newPED-X twice before farrowing.

1. Virus shedding of PEDv in relation to vaccination of newPED-X.

PEDv was detected in the feces of suckling piglets after feedback. However, PEDv was not detected in the feces in the farrowing and piglet houses at 4 months and 10 months after vaccination with newPED-X.

2. Growth rate following weaning after newPED-X vaccination

The number of weaned piglets after feedback did not differ significantly but the condition of the weanlings deteriorated due to the persistent diarrhea caused by PEDv in the farrowing houses. However, the condition of weaned piglets improved and the growth rate following weaning increased by 2.1% after vaccination with newPED-X. This resulted to an increase of 1,312 market hogs per year and is equivalent to approximately at least 0.4 M USD.

Moreover, R.O.I. after newPED-X administration was calculated at 9.33.

It was demonstrated that regular vaccination of newPED-X on sows had a positive effect on reducing economic losses due to death and diarrhea of suckling piglets. It was confirmed that usage of the vaccine is not only beneficial for the herd’s health but also provides a profit of at least 9.33 times more than the vaccination cost.

The vaccination of sows can decrease the diarrhea and death in sucking piglets, but farms must still have additional quarantine measures against PEDv circulation and continuously apply newPED-X to sows since the maternal derived antibodies remains until 6 weeks old only.

Disclosure of Interest: None Declared.