Developing Tailor-Made Microbial Consortium for Effluent Remediation

The work describes a biofilm-based soluble sulphate reduction system, which can treat up to 1600 ppm of soluble sulphate within 3.5 hours of incubation to discharge level under ambient condition using a well-characterized sulphate-reducing bacterial (SRB) consortium. This system ensures the treatment of 1509 litres of sulphate solution in 24 hours using a 220-litre bioreactor. Performance of the system during series operation was compromised, indicating the presence of inhibitor in solution at a toxic level. A single unit bioreactor would be the ideal configuration for this consortium. Modified designs of bioreactors were tested for optimization of the process using response surface methodology (RSM), where the system could function optimally at an initial sulphate concentration of 1250 ppm with a flow rate of 1.8 litre/hour. The time course of sulphate reduction yielded a parabolic profile (with coefficient of determination r 2 = 0.99 and p value < 0.05). The rate of sulphate reduction was found to be independent of seasonal variation as well as the specific design characteristic

SARS-CoV-2 seroprevalence among the general population and healthcare workers in India, December 2020–January 2021

Background: Earlier serosurveys in India revealed seroprevalence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) of 0.73% in May–June 2020 and 7.1% in August–September 2020. A third serosurvey was conducted between December 2020 and January 2021 to estimate the seroprevalence of SARS-CoV-2 infection among the general population and healthcare workers (HCWs) in India. Methods: The third serosurvey was conducted in the same 70 districts as the first and second serosurveys. For each district, at least 400 individuals aged ≥10 years from the general population and 100 HCWs from subdistrict-level health facilities were enrolled. Serum samples from the general population were tested for the presence of immunoglobulin G (IgG) antibodies against the nucleocapsid (N) and spike (S1-RBD) proteins of SARS-CoV-2, whereas serum samples from HCWs were tested for anti-S1-RBD. Weighted seroprevalence adjusted for assay characteristics was estimated. Results: Of the 28,598 serum samples from the general population, 4585 (16%) had IgG antibodies against the N protein, 6647 (23.2%) had IgG antibodies against the S1-RBD protein, and 7436 (26%) had IgG antibodies against either the N protein or the S1-RBD protein. Weighted and assay-characteristic-adjusted seroprevalence against either of the antibodies was 24.1% [95% confidence interval (CI) 23.0–25.3%]. Among 7385 HCWs, the seroprevalence of anti-S1-RBD IgG antibodies was 25.6% (95% CI 23.5–27.8%). Conclusions: Nearly one in four individuals aged ≥10 years from the general population as well as HCWs in India had been exposed to SARS-CoV-2 by December 2020