“The antibodies generated by some old vaccine strains have their neutralising capability reduced by the new PPV”

Professor André Felipe Streck of the University of Caxias do Sul in Brazil gives his expert view of the key question: Are long-established PPV vaccines still effective when faced with new field strains of the virus? He also discusses whether years of vaccinating sow herds against reproductive failure due to the porcine parvovirus PPV have played any part in the mutation of the virus into newer forms. (Running time: 20 minutes)

“We have an evolutionary process with this virus… evolutionary hot-spots on the surface of the virus, located at points in contact with the host’s immune system”

In southern Brazil, Professor André Felipe Streck of the Institute of Biotechnology at the University of Caxias do Sul leads us through the changing story of the porcine parvovirus PPV. Long considered a stable virus that could be controlled by vaccines developed four decades ago, its evolution into diverse forms has become evident since the year 2000. Newer strains display amino acid substitutions in the capsid or external protein layer of the virus which influence antigenicity. (Running time: 33 minutes)

“An important message for veterinarians and farmers is that the spread of ASF from farm to farm is possible with a very small dose of the virus”

Professor Grzegorz Wozniakowski is Head of the Department of Swine Diseases at the National Veterinary Research Institute in Puławy, Poland, and also Director of Poland’s National Reference Laboratory on African swine fever. In addition to sharing his expertise on the diagnostic methods available for ASF, he describes a Polish study published in 2020 which demonstrated a delay of up to five days after infection before the appearance of clinical signs and found that even an extremely low titre of the viral strain tested was enough to infect pigs.
(Running time: 34 minutes)

“Highly pathogenic African swine fever virus is present in all wild boar in Poland; there are no safe levels of wild boar density”

Poland’s first incidence of ASF was in wild boar in 2014 and since then it has recorded over 7,000 wild-boar cases of the disease as well as nearly 270 outbreaks in domestic pigs, notes Professor Grzegorz Wozniakowski, Director of the country’s National Reference Laboratory on African swine fever. He sets out Polish experiences over the past six years in dealing with the risk of very virulent strains of the ASF virus passing to farm pigs from forest swine.
(Running time: 33 minutes) 

“It is feasible to do it in a year, but we are going to be busy!”

In 2020, Boehringer Ingelheim has sponsored its latest annual European PRRS Research Awards which offer 25,000 Euros towards the funding of each of three research projects that are potentially of practical benefit in controlling PRRS. Hear the winners of the 2020 Awards describe the research they propose, given the time limit of completing the work in one year. A practitioner-led project in Denmark is to examine the impact of piglet weaning strategies on PRRSv in the nursery. An international team led from The Netherlands will use whole-genome sequencing to investigate genetic recombination in type-1 PRRS viruses. And, a study in Spain aims to measure how biosecurity measures against PRRS relate to the physical performance and profitability of commercial swine farms. Running time: 30 minutes

“Vaccinating animals decreases clinical signs and also the amount of viruses in the air, so it is a good mechanism to reduce airborne transmission”

While taking her doctorate in veterinary population medicine at the University of Minnesota, Dr. Carmen Alonso investigated the extent to which swine viruses were transmitted in the air from a farm suffering an outbreak. In this conversation she describes the influence of particle size on the airborne transmission of the viruses of PRRS, Influenza A and the porcine epidemic diarrhoea syndrome --- and explains how even large particles with a high viral load can be carried a long distance. (Running time: 34 minutes) 

“A weak spot for PRRS control comes when you take boar semen or gilts from outside into a herd”

Better surveillance for PRRS at boar stations in Denmark has followed a breakdown at a PRRS-negative boar station which led to sharply reduced sow productivity at herds in the area, reports Professor Lars Erik Larsen of the University of Copenhagen. Investigators discovered that the break involved a recombinant form of the virus, combining strains from two vaccines used at a sow herd about 5 kilometres from the boar station. (Running time: 28 minutes) 

“Extra biosecurity should begin outside the farm…our graphics for training emphasise not only the risks from contacts within the farm, but also from those that workers have on their way to work and from their families.”

We talk to international veterinary consultant and population medicine expert Dr. Carmen Alonso about her recommendations for the precautions that a swine farm should take, to shield its farm workers from the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) infection responsible for Covid-19 disease in humans during the worldwide pandemic. Dr. Alonso reports good results from using visual aids to convey key messages to the people who work on the farm.  (Running time: 32 minutes)