Streptococcus anginosus Throat colonization in Healthy School going children

Abstract

Background: Streptococcus anginosus was most commonly considered as commensals and closely related to Streptococcus pyogenes. Recovery of this bacteria from the throats has been reported to exceed that of S. pyogenes in regions where streptococcal disease is endemic. Infection with these bacteria may cause acute rheumatic fever (ARF) and its sequelae rheumatic heart disease (RHD) in susceptible individual. Molecular mimicry and autoimmunity probably play a crucial role in the pathogenesis. M protein in streptococci shares structural similarities with cardiac proteins such as myosin and the antibodies produced in patient cross-react with both M protein and heart tissue leading to RHD that causes significant morbidity and mortality in developing countries. The incidence of ARF peaks between 5-15years of age and high burden of RHD is seen in Asia. Strptococcus anginosus being the most common beta hemolytic group C streptococcus isolated from the human throat. The present study provides epidemiological clues of this bacteria which is necessary in developing preventive measures. Objective: To study the prevalence of Streptococcus anginosus in throat among healthy school children. Method: Throat swabs were collected after taking consent from 3, 416 children. The organism were isolated in sheep blood agar and beta hemolytic organisms were identified as Streptococcus anginosus by Vitek 2 compact, an automated system. Result: Out of 3416 throat samples only six samples had beta hemolytic Streptococcus anginosus. Conclusion: The present study showed the presence of beta hemolytic Streptococcus anginosus. Further study regarding M genes are required for knocking the virulence factors by developing suitable vaccines.