The Situation of zoonosis in patients at Chaiyaphum Province: Streptococcus suis infection and drug susceptibility patterns

Abstract

Background: Streptococcus suis (S. suis) is a Gram-positive bacterium that can cause zoonotic infections, particularly in humans. In Thailand, the mortality rate associated with S. suis infections is relatively high, ranging from 4.7% to 8.0%.

            Objective: This study aimed to investigate the incidence of S. suis infections and drug susceptibility patterns in patients at Chaiyaphum Provincial Hospital and to compare the mortality rate with other provinces in Health Region 9.

            Methods: A retrospective analytical research study was conducted using data from 100 patients with S. suis infections between 2021 and 2024. Statistical analysis included the Chi-square test, Kruskal-Wallis test, and Mann-Whitney U test.

            Results: S. suis was detected in 0.2%, 0.6%, 0.5%, and 0.8% of samples in 2021, 2022, 2023, and 2024, respectively. The prevalence in 2021 was significantly lower than other years (P< .05). The bacteria showed 100% susceptibility to Levofloxacin and Vancomycin, followed by Chloramphenicol (91%) and Cefotaxime (88%). Of the 100 samples, 73% were from males with an average age of 57.9 years. Blood cultures were positive in 92% of cases, followed by cerebrospinal fluid (8%). The emergency department had the highest number of cases, followed by internal medicine wards. The outbreak was concentrated in Bamnet Narong district for three consecutive years (2021-2023), and in Chatturat district in 2024 (51.9%). The mortality rate in Health Region 9 was highest in Surin (12.5%), followed by Buriram (7.7%), Chaiyaphum (7.4%), and Nakhon Ratchasima (5.2%).

            Conclusion: The incidence of S. suis infections in Chaiyaphum province was relatively stable from 2021 to 2024. However, a decreasing susceptibility to penicillin was observed. Chattura, Mueang, Noen Sanga, and Thep Sathit districts were identified as areas of concern. Promoting public awareness about food safety and zoonotic diseases is crucial to reduce the incidence of S. suis infections.