The Swine Health Information Center called for proposals for improved oral fluids PCR (polymerase chain reaction) sensitivity. Although the deadline for accepting these research proposals was August 25, the aim is to improve oral fluids’ PCR sensitivity. 
Dr. Paul Sundberg, the Executive Director of the SHIC, said the genesis of this is a question about able to use oral fluids for African Swine Fever monitoring and surveillance. 
“CFIA [Canadian Food Inspection Agency] in Winnipeg, MB and USDA on Plum Island both did experiments with ASF by infecting one pig in a pen of 25,” said Dr. Sundberg. “They followed that pen through the infection using oral fluids and whole blood samples to get an idea of the timeliness of being able to use oral fluids.” 
He said one they found that very often, the oral fluids will be positive with ASF when they infect the pigs, and that’s a good thing, so they have a lot of confidence in a positive result.  
The researchers question the sensitivity of the test itself because there is some question about detecting ASF in that first infected pig. Even though it may be shedding, it may be viremic and that oral fluid may still be negative. 
“We want to determine if we can increase the sensitivity of the PCR test for detection,” said Dr. Sundberg. “When you look at oral fluids with that very early infection, we think it may be a dilution factor with the oral fluids from the other pigs not infected.” 
That may be the reason it is testing negative, meaning that the number of viruses in the collective sample would be very low, which may be lower than the detection limit.  
Dr. Sundberg said first they’re looking for urgency and timeliness of this research.  
“We don’t want to have a situation where we get African Swine Fever in Canada, and we say, gee, we wish we’d had that done. We want to finish it before that happens, and we don’t know when that will be.” 
He said they would also look at mycoplasma, for example, looking at PRRS, mycoplasma, and PED, to use them as surrogates for ASF.  
“So we don’t have to use ASF directly, but we can do a better job with extraction using those types of pathogens.” 
The plan is to get researchers that will partner with producers to use their oral fluids; they will send in any way to decrease costs, prioritize, and urgently. 
While saying earlier that research points at ASF are certainly one of the primary considerations, but with mycoplasma, PRRS, and PED, it’s a way to detect very low levels and increase the sensitivity of the PCR test and do a better job.  
“Once we can do a better job looking for early infections, where perhaps the number of pathogens is low, we may be able to do a better job of managing them before they become real issues,” said Dr. Sundberg. “We have long term potential for benefits with doing this type of research to try to improve our diagnostics.” 
Dr. Sundberg said there is more information on the website or email him directly. He’s looking forward to reviewing the proposals expecting to have more than they can fund. He’s looking to collaborate with the National Pork Board in the United States.  
They have a key performance indicator, a KPI for 2020, which talks about diagnostics and looks forward to getting more proposals that SHIC can share, collaborate, and make some good progress on this issue quickly. •
— By Harry Siemens