ABSTRACT
COVID-19 is a respiratory disease caused by a recently discovered, novel coronavirus, SARS-COV2. The disease has led to over 81 million confirmed cases of COVID-19, with close to 2 million deaths. In the current social climate, the risk of COVID-19 infection is driven by individual and public perception of risk and sentiments. A number of factors influences public perception, including an individuals belief system, prior knowledge about a disease and information about a disease. In this paper, we develop a model for COVID-19 using a system of ordinary differential equations following the natural history of the infection. The model uniquely incorporates social behavioral aspects such as quarantine and quarantine violation. The model is further driven by peoples sentiments (positive and negative) which accounts for the influence of disinformation. Peoples sentiments were obtained by parsing through and analyzing COVID-19 related tweets from Twitter, a social media platform across six countries. Our results show that our model incorporating public sentiments is able to capture the trend in the trajectory of the epidemic curve of the reported cases. Furthermore, our results show that positive public sentiments reduce disease burden in the community. Our results also show that quarantine violation and early discharge of the infected population amplifies the disease burden on the community. Hence, it is important to account for public sentiment and individual social behavior in epidemic models developed to study diseases like COVID-19.
ABSTRACT
A multiplex PCR kit that detects three major virulence genes, gelE, hyl and asaI, in Enterococcus faecalis was developed. Analyses of the available sequences of three major virulence genes and designed primers allowed us to develop the three-gene, multiplex PCR protocol that maintained the specificity of each primer pair. The resulting three amplicon bands for gelE, hyl and asaI were even and distinct with product sizes of 213, 273 and 713 bp, respectively. The multiplex PCR procedure was validated with a total of 243 E. faecalis strains that included 02 ATCC strains, 109 isolates from marine samples (sediment, water and sea foods), 22 isolates from cattle fodder, 79 isolates fresh water samples and 31 isolates from nosocomial samples. Specificity of the kit was indicated by amplification of only three major virulent genes gelE, hyl and asaI without any nonspecific bands. Tests for the limit of detection revealed that amplified genes from the sample with a minimum of 104 CFU/g or CFU/mL (10 cells/reaction) of E. faecalis and lower cell load samples, after a 3 h enrichment in NIOT-E. faecalis enrichment medium at 37 °C, a sensitivity level of 10 CFU/g or CFU/mL was achieved.
