Epidemiological and pathogenic investigation on the first case of human Streptococcus suis type 2 infection in Minhang District, Shanghai / 公共卫生与预防医学

ABSTRACT

Objective To investigate and analyze the epidemiological and pathogenic characteristics on a case of human Streptococcus suis type 2 infection in Minhang District, Shanghai, and to provide evidence for early warning and prevention and control measures of rare and imported zoonotic acute infectious diseases in Shanghai. Methods By inquiring the patient medical history and epidemiological history and on-site environmental investigation, the infection route and source of the case were examined. The pathogenic culture of cerebrospinal fluid (CSF) was used to isolate Streptococcus suis, and Vitek2GP was used to identify the isolated strains. The PCR technique was used to detect species specific genes and virulence genes. Results The clinical manifestations of the patient were high fever with headache, nausea, vomiting and stiff neck. Blood tests showed a significant increase in c-reactive protein, an increase in lymphocyte percentage, and a decrease in platelet count. Head CT examination showed bilateral ethmoidal sinus and bilateral maxillary sinus inflammation, and significantly increased CSF white blood cell count and immunoglobulin. The case's CSF sample was positive for species specific genes (16SrRNA) and 2 virulence genes (cps-2j and ef). Conclusion This case was human Streptococcus suis type 2 with meningitis symptoms. Good prognosis was associated with timely diagnosis and treatment as well as the types of virulence factors. Medical institutions should identify early infection and take timely treatment as soon as possible to avoid severe illness and death cases. Departments of agriculture, health, market management, and others should consummate the reporting mechanism of animal epidemic situation, and establish necessary active sentinel monitoring.