Isolation and identifcation of Streptococcus suis from sick pigs in Bali, Indonesia

Objective: Streptococcus suis (S. suis) is a causative agent for various syndromes in pigs. It can be transmitted to humans with typical symptoms of meningitis and death. Although human infections have been confrmed at Bali Referral Hospital, Indonesia, since 2014, the bacteria have not been isolated from pigs. Here, we provide confrmation of the presence of the bacteria in sick pigs in the province. Results: Streptococcus suis was confrmed in 8 of 30 cases. The fnal confrmation was made using PCR and sequencing of the glutamate dehydrogenase (GDH) and recombination/repair protein (recN) gene fragments. Upon PCR serotyping, two were confrmed to be serotype 2 or 1/2. Prominent histopathological lesions of confrmed cases were meningitis, endocarditis, pericarditis, bronchopneumonia, enteritis and glomerulonephritis. The dominant infammatory cells were neutrophils and macrophages. Further research is needed to understand the risk factors for human infection. Community awareness on the risk of contracting S. suis and vaccine development are needed to prevent human infections.