What is found in apparently healthy slaughter pigs when we look for S. suis?
Among apparently healthy slaughter pigs in Thailand, S. suis was common and genetically diverse, but molecular markers did not perfectly distinguish commensal from pathogenic strains.
Among apparently healthy slaughter pigs in Thailand, S. suis was common and genetically diverse, but molecular markers did not perfectly distinguish commensal from pathogenic strains.
Problem: Clinically healthy pigs can carry S. suis populations that include lineages relevant to disease in pigs or humans.
Methods: Nasopharyngeal swabs were collected from 322 slaughter pigs at three slaughterhouses in a high-density swine region of Thailand. A total of 238 isolates were recovered and a subset underwent detailed molecular pathotyping.
1. S. suis was detected in 194 of 322 pigs, or 60.25%, and 39.92% of isolates were non-typeable with the method used.
2. The most common serotypes were 8, 19, 29, 3, and 2, and human-associated clades were identified among the characterized isolates.
3. Molecular markers could not perfectly distinguish commensal from pathogenic isolates, so detection in a healthy pig does not automatically indicate disease or zoonotic risk.
Original publication
Lunha K, Chumpol W, Jiemsup S, et al. Serotype Distribution and Pathotypic Characteristics of Streptococcus suis Isolates from Slaughtered Pigs in a High-Density Pig Farming Area in Thailand. Transboundary and Emerging Diseases. 2024;2024:3186518.