Isolation and identification 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 confirmed at
Bali Referral Hospital, Indonesia, since 2014, the bacteria have not been
isolated from pigs. Here, we provide confirmation of the presence of the
bacteria in sick pigs in the province. Results S. suis was confirmed in 8
of 30 cases. The final confirmation was made using PCR and sequencing of
the glutamate dehydrogenase (GDH) and recombination/repair protein (recN)
gene fragments. Upon PCR serotyping, two were confirmed to be serotype 2
or 1/2. Prominent histopathological lesions of confirmed cases were
meningitis, endocarditis, pericarditis, bronchopneumonia, enteritis and
glomerulonephritis. The dominant inflammatory 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.