Recombinant vaccine strain identified originating from living attenuated PRRS vaccines

The European Medicines Agency (EMA) is performing further research after a recombinant strain containing two living attenuated Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) vaccines was identified in Denmark. The recombinant strain was associated with clinical symptoms of PRRS, such as reduced fertility in sows, increase in the number of rejections, increased in piglet mortality, reduced appetite and respiratory conditions in young pigs.

Recombination between various strains of PRRSV, including living attenuated type 1 PRRSV vaccine strains, is a known phenomenon already reported in the scientific literature. The spread of a recombinant PRRSV strain, like this one was identified in Denmark, can happen anywhere at any time.

Precautionary Measures
To limit the occurrence of recombinant vaccine strains of living attenuated PRRSV vaccines, the use of various living attenuated PRRSV vaccines in a population, both simultaneously and successive, is strongly contraindicated. It is recommended to vaccinate all animals in a population.

Living attenuated PRRSV vaccines must not be used in PRRS naive populations in which the presence of PRRSV has not been determined with reliable diagnostic methods.

Recommendations for veterinarians
Increased monitoring of every suspected clinical symptom of PRRS in a vaccinated population is recommended. These symptoms can be reported, just like other adverse events, to adversedrugreactions_vet@fagg-afmps.be or via https://www.vetcompendium.be/nl/node/29.

Reporting via this path is also requested when the recombination is noted between vaccine strains or between a vaccine strain and a wild type virus during sequencing.

The following living attenuated vaccines for PRRSV are on the market in Belgium.

Vaccine Marketing authorisation holder Active substance
Ingelvac PRRS MLV Boehringer Ingelheim Vetmedica GmbH Porcine Respiratory and Reproductive Syndrome Virus (PRRSV), Live, Attenuated quantum satis
Ingelvac PRRSFLEX EU Boehringer Ingelheim Vetmedica GmbH Porcine Respiratory and Reproductive Syndrome Virus (PRRSV), Live, Attenuated quantum satis
Porcilis PRRS Intervet International BV Porcine Respiratory and Reproductive Syndrome Virus (PRRSV), Live, Attenuated quantum satis
ReproCyc PRRS EU et ImpranFLEX Boehringer Ingelheim Vetmedica GmbH Porcine Respiratory and Reproductive Syndrome Virus (PRRSV), Live, Attenuated quantum satis
Suvaxyn PRRS MLV Zoetis Belgium SA Porcine Respiratory and Reproductive Syndrome Virus (PRRSV), Live, Attenuated quantum satis
Unistrain PRRS Laboratorios Hipra SA Porcine Respiratory and Reproductive Syndrome Virus (PRRSV), Live, Attenuated quantum satis

 

Last updated on
02/01/2020