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Dass, S. C.

Publications and source records attributed to Dass, S. C..

2 recordsLinked to original sources

A biosafety level 2 surrogate for studying SARS-CoV-2 survival in food processing environmental biofilms

Meat processing plants have been at the center of the SARS-CoV-2 pandemic. There are several factors that contribute to the persistence of SARS-CoV-2 in meat processing plants and one of the factors is the formation of a multi-species biofilm with virus. Biofilm can act as a reservoir in protecting, harboring, and dispersing SARS-CoV-2 from biofilm to the meat processing facility environment. We used Murine Hepatitis Virus (MHV) as a surrogate for SARS-CoV-2 virus and meat processing facility drain samples to develop mixed-species biofilms on commonly found materials in processing facilities (Stainless-Steel (SS), PVC and tiles). The results showed that MHV was able to integrate into the environmental biofilm and survived for a period of 5 days at 7{degrees}C. There was no significate difference between the viral-environmental biofilm biovolumes developed on different materials SS, PVC, and tiles. There was a 2-fold increase in the virus-environmental biofilm biovolume when compared to environmental biofilm by itself. These results indicate a complex virus-environmental biofilm interaction which is providing enhanced protection for the survival of viral particles with the environmental biofilm community.

microbiology↗

Modeling the Impact of Lock-down on COVID-19 Spread in Malaysia

After a breakdown notified in Wuhan, China in December 2019, COVID-19 is declared as pandemic diseases. To the date more than 13 million confirmed cases and more than half a million are dead around the world. This virus also attached Malaysia in its immature stage where 8718 cases were confirmed and 122 were declared as death. Malaysia responsibly controlled the spread by enforcing MCO. Hence, it is required to visualize the pattern of Covid-19 spread. Also, it is necessary to estimate the impact of the enforced prevention measures. In this paper, an infectious disease dynamic modeling (SEIR) is used to estimate the epidemic spread in Malaysia. The main assumption is to update the reproduction number Rt with respect to the implemented prevention measures. For a time-frame of five month, the Rt was assumed to vary between 2.9 and 0.3. Moreover, the manuscript includes two possible scenarios: the first will be the extension of the stricter measures all over the country, and the second will be the gradual lift of the lock-down. After implementing several stages of lock-down we have found that the estimated values of the Rt with respect to the strictness degree varies between 0.2 to 1.1. A continuous strict lock-down may reduce the Rt to 0.2 and accordingly the estimated active cases will be reduced to 20 by the beginning of September 2020. In contrast, the second scenario considers a gradual lift of the enforced prevention measures by the end of June 2020, here we have considered three possible outcomes according to the MCO relaxation. Thus, the estimated values of Rt = 0.7, 0.9, 1.1, which shows a rapid increase in the number of active cases. The implemented SEIR model shows a close resemblance with the actual data recorded from 10, March till 7, July 2020. Author summaryConceptualization, A.A.A; methodology, A.A.A, N.M; validation, A.A.A, N.M; formal analysis, A.A.A; investigation, N.M, A.A.A; resources, G.E.M.A, L.T; data collection, L.T, N.M; writing--original draft preparation, A.A.A, L.T, G.E.M.A, N.M; writing--review and editing, V.S.A, S.C.D, B.S.G, P.S, S.A.B.M.Z, N.M; visualization, N.M; supervision, V.S.A; project administration, V.S.A. All authors have read and agreed to the published version of the manuscript

bioinformatics↗