Survival of a surrogate African swine fever virus-like algal virus in feed matrices using a 23-day commercial United States truck transport model

• Published in: Frontiers in microbiology 2022-12, Vol.13, p.1059118
• Main Authors: Palowski, Amanda, Balestreri, Cecilia, Urriola, Pedro E, van de Ligt, Jennifer L G, Sampedro, Fernando, Dee, Scott, Shah, Apoorva, Yancy, Haile F, Shurson, Gerald C, Schroeder, Declan C
• Format: Article
• Language: English
• Subjects: African swine fever virus; Emiliania huxleyi virus; feed; Microbiology; NCLDVs; transport; viability PCR
• ISSN: 1664-302X; 1664-302X
• DOI: 10.3389/fmicb.2022.1059118

African swine fever virus (ASFV) is a member of the nucleocytoplasmic large DNA viruses (NCLDVs) and is stable in a variety of environments, including animal feed ingredients as shown in previous laboratory experiments and simulations. virus (EhV) is another member of the NCLDVs, which has a restricted host range limited to a species of marine algae called . This algal NCLDV has many similar morphological and physical characteristics to ASFV thereby making it a safe surrogate, with results that are applicable to ASFV and suitable for use in real-world experiments. Here we inoculated conventional soybean meal (SBMC), organic soybean meal (SBMO), and swine complete feed ( ) matrices with EhV strain 86 (EhV-86) at a concentration of 6.6 × 10 virus g , and then transported these samples in the trailer of a commercial transport vehicle for 23 days across 10,183 km covering 29 states in various regions of the United States. Upon return, samples were evaluated for virus presence and viability using a previously validated viability qPCR (V-qPCR) method. Results showed that EhV-86 was detected in all matrices and no degradation in EhV-86 viability was observed after the 23-day transportation event. Additionally, sampling sensitivity (we recorded unexpected increases, as high as 49% in one matrix, when virus was recovered at the end of the sampling period) rather than virus degradation best explains the variation of virus quantity observed after the 23-day transport simulation. These results demonstrate for the first time that ASFV-like NCLDVs can retain viability in swine feed matrices during long-term transport across the continental United States.