Background: Group A streptococcus (GAS) causes a wide variety of life threatening diseases in humans and the incidence of such infections is high in developing countries like India. Although distribution of emm types of GAS in India has been described, there is a lack of data describing either the comparative distribution of emm types in throat versus skin isolates, or the distribution of certain virulence factors amongst these isolates. Therefore in the present study we have monitored the emm type pattern of Group A streptococcus throat and skin isolates from India. Additionally, the association of these isolates with closely related sic (crs), a multifunctional compliment binding virulence factor, was also explored. Results: Of the 94 (46 throat and 48 skin) isolates analyzed, 37 emm types were identified. The most frequently observed emm types were emm49 (8.5%) and emm112 (7.5%) followed by 6.5% each of emm1-2, emm75, emm77, and emm81. Out of 37 emm types, 27 have been previously reported and rest were isolated for the first time in the Indian Community. The predominant emm types of throat (emm49 and emm75) samples were different from those of skin (emm44, emm81 and emm112) samples. After screening all the 94 isolates, the crs gene was found in six emm1-2 (crs1-2) isolates, which was confirmed by DNA sequencing and expression analysis. Despite the polymorphic nature of crs, no intravariation was observed within crs1-2. However, insertions and deletions of highly variable sizes were noticed in comparison to CRS isolated from other emm types (emm1.0, emm57). CRS1-2 showed maximum homology with CRS57, but the genomic location of crs1-2 was found to be the same as that of sic1.0. Further, among crs positive isolates, speA was only present in skin samples thus suggesting possible role of speA in tissue tropism. Conclusion: Despite the diversity in emm type pattern of throat and skin isolates, no significant association between emm type and source of isolation was observed. The finding that the crs gene is highly conserved even in two different variants of emm1-2 GAS (speA +ve and -ve) suggests a single allele of crs may be prevalent in the highly diverse throat and skin isolates of GAS in India.

Real-time RT-PCR is used as a gold standard method for the diagnosis of COVID-19. Since real-time RT PCR is nucleic acid-based, it is a highly sensitive and specific test. However, this test takes 4–8 h to generate results and, in emergency settings, this delay may prove fatal for certain patients. The frequent surge in COVID cases increases patient load in emergency settings. Thus, a nucleic acid-based rapid POC test is required that can generate results quickly as well as being comparable to real-time RT-PCR. In this study, comparison of real-time RT-PCR was carried out using the rapid nucleic acid-based LAMP method. Nasopharyngeal swabs were taken in duplicate from patients visiting the kiosk and were analyzed for the presence of the SARS-CoV-2 virus by both real-time RT-PCR and LAMP techniques ID NOW(bbott). Out of 14 positive and 31 negative samples tested by real-time RT-PCR, 13 samples were identified as positive and 31 were observed as negative with the LAMP-based test. Hence, the sensitivity and specificity of this method were found to be 92.9% and 93.5%, respectively. Therefore, LAMP-based point-of-care testing has the potential to be used in hospital emergency settings for quick diagnosis of critically ill patients, and the information generated here will further draw the attention of policymakers toward such nucleic acid-based rapid tests.