Human Streptococcus suis Infections in Thailand: Epidemiology, Clinical Features, Genotypes, and Susceptibility

Abstract

Streptococcus suis is a zoonotic pathogen causing substantial economic losses to the pig industry, as well as being a human health burden due to infections worldwide, especially in Southeast Asia. In Thailand, there was high cumulative incidence in humans during 1987–2021, mostly in males. At least five large outbreaks have been documented after the largest outbreak in China in 2005, which was related to the consumption of raw pork or dishes containing pig’s blood. The major clinical features are sepsis or meningitis, with hearing loss a major complication of S. suis disease. Thai human S. suis isolates have shown diversity in serotypes and sequence types (STs), with serotype 2 and STs 1 and 104 being major genotypes. β-Lactam antibiotics can be used in empirical treatment for human S. suis infections; however, intermediate resistance to penicillin has been reported. Reducing S. suis incidence in Thailand requires a multidimensional approach, with combined efforts from the government and public health sectors through policy, regulations, education, and active surveillance.

Molecular Epidemiology of Underreported Emerging Zoonotic Pathogen Streptococcus suis in Europe

“…We observed an increase in reported cases after 1999 ( Appendix Figure 2); however, this increase could have been caused by heightened awareness after a severe outbreak in China in 2005 and by more precise bacterial identification techniques ( 37 ). Moreover, in Thailand, a country where S. suis is a notifiable disease, reported infections have increased in the past few years ( 10 ).…”

Genomic epidemiology in Streptococcus suis: Moving beyond traditional typing techniques

“…These latter CCs are also present in Australia and some parts of Asia [ 4 ], whereas CC1 strains are more prevalent in Europe, Asia, and South America [ 1 , 60 , 61 ]. CC20 is important in The Netherlands [ 62 ], whereas CC104 and CC233 (ST233, ST379, and ST1656) have caused outbreaks and are endemic to Thailand [ [63] , [64] , [65] ]. CC16 and CC94 predominate among swine isolates in Europe; however, human cases caused by isolates of the latter CCs have also been reported in Thailand [ 1 , 63 , 66 ].…”

Meningitis and sepsis caused by Streptococcus suis in an elderly woman: A CARE-compliant case report

“…[2] For the anti-infection regimen of S suis infection, β-lactam antibiotics are used empirically to treat S suis infections and have been shown to be safe and efficacious. [17] However, for bacterial meningitis without knowledge of the causative pathogen, many guidelines recommend vancomycin plus β-lactam antibiotics. [18,19] In our patient, before the etiological results were obtained, the patient received anti-infection treatment with vancomycin and meropenem with extensive empirical coverage, which showed high efficacy.…”