Streptococcus suis infection (diagnosis, prevention and treatment)

Abstract

Streptococcus suis (S. suis) is an important zoonotic pathogen, which can cause serious diseases such as meningitis, pneumonia, endocarditis, polyserositis, arthritis, septicemia and abortion in pigs. In recent years, the incidence rate of streptococcal meningitis has shown a significant upward trend. For humans, the threat of S. suis is also increasing. Therefore, strengthening the prevention and control of the disease has become an urgent task. The premise of inducing meningitis is that S. suis invades the central nervous system and breaches the blood brain barrier (BBB). Due to the presence of the blood brain barrier, even though bacteria can enter the blood through the skin mucosa and other parts, a large number of bacteria in the blood cannot enter the brain through the blood brain barrier. The body relies on this barrier to protect the brain tissue from damage and maintain the homeostasis of the central nervous system. Brain microvascular endothelial cell (BMEC) is the basic component of the blood brain barrier, and a variety of neurological diseases are related to the dysfunction of the blood brain barrier, and S. suis can interact with brain microvascular endothelial cell and then cross the the blood brain barrier to cause central nervous system infection. However, the antibiotics used to treat the infection cannot pass through the barrier to reach the therapeutic target site, which is the key to the difficulty in the control of bacterial meningitis. Therefore, elucidating the mechanism of S. suis breaking through the blood brain barrier into central nervous system is an important breakthrough in developing S. suis meningitis control strategy. Due to long-term unjustified use of antibiotics, bacterial resistance has increased, and antibiotic treatment disrupts the normal homeostasis of the body and intestinal flora. The problems caused by long-term, large-scale use of antibiotics are becoming more and more serious. Meningitis caused by streptococcus suis can no longer be treated with conventional antibiotics. Therefore, It is necessary to have a thorough understanding of the pathogenesis of meningitis. This article reviews the discovery the clinical signs and symptoms of the disease, pathological changes, laboratory, measures of prevention and treatment for streptococcal infection of pigs in recent years.