ABSTRACT
In this manuscript, we model and visualize the region-wise trends of the evolution to COVID-19 infections employing a SIR epidemiological model. The SIR dynamics are expressed using stochastic differential equations. We first optimize the parameters of the model using RMSE as loss function on the available data using L-BFGS-B gradient descent optimisation to minimise this loss function. This helps to gain better approximation of the models parameter for specific country or region. The derived parameters are aggregated to project future trends for the Indian subcontinent for next 180 days, which is currently at an early stage within the infection cycle. The projections are meant to function a suggestion for strategies for the socio-political counter measures to mitigate COVID-19. This study considers the current data for India from various open sources. The SIR models prediction is found following the actual trends till date. The inflection point analysis is important to find out which countries have reached their inflection point of the number of infection. We found that if current restrictions like lockdown in India continues with same control, then India will observe it[s] peak in active patients count on 22 May 2020, it will take 28 August 2020 for 90% of the peak active infections to end. Inspired from the study of DDI Lab at Singapore university of technology and design (SUTD), this study additionally tries to model and quantify the variations in the count of active patients in the country which might occur due to effect of waiver in restrictions. It should be noted that these results were predicted using COVID-19 data of India till 03 May 2020.
ABSTRACT
OBJECTIVE@#To determine the occurrence of class A and class C β-lactamase genes and their co-occurrence in Indian Enterobacteriaceae.@*METHODS@#52 third generation cephalosporin resistant isolates were phenotypically detected by combination disk method and screened by PCR to identify class A and class C type β-lactamase genes.@*RESULTS@#Of the 52 isolates, 94.2% (49) were found harboring any of the bla(ESBL(s)). bla(CTX-M), bla(SHV) and bla(TEM) were present in 82.6% (43/52), 59.6% (31/52), and 42.3% (22/52) isolates, respectively. Of the 49 ESBL positive isolates 57.1% (28/49) showed co-occurrence of bla(ampC) with bla(ESBL(s)). On the contrary, the collection from 2009 showed their co-occurrence in 81.4% isolates.@*CONCLUSIONS@#The comparative study shows a downward trend for co-existence of bla(ESBL(s)) with bla(ampC) from 2009 to 2010. Further large scale studies are needed to address the co-occurrence of class A and class C β-lactamases in India and the resistance trend occurring over a period of time.
Subject(s)
Humans , Cephalosporin Resistance , Genetics , Enterobacteriaceae , Genetics , Genes, Bacterial , India , Polymerase Chain Reaction , beta-Lactamases , GeneticsABSTRACT
OBJECTIVE@#To delineate the frequency of occurrence of bla(CTX-M), bla(TEM), and bla(SHV) in Enterobacteriaceae from North-Indian tertiary hospital.@*METHODS@#A random collection of a subset of 45 Escherichia coli (E. coli) and 28 Klebsiella pneumoniae (K. pneumoniae) that was resistant to a third generation cephalosporin and obtained during 2007-2008 was selected for detailed screening for bla(CTX-M), bla(TEM), and bla(SHV) by monoplex PCRs. The isolates demonstrating the presence of bla(CTX-M) alleles were characterized for the specific CTX-M-genogroup by using a multiplex PCR.@*RESULTS@#Resistance to cefoperazone, ceftazidime, ceftriaxone, cefotaxime, cefoxitin and piperacillin was 100% each in K. pneumoniae isolates, whereas these resistance-rates for E. coli isolates were 93.1%, 83.8%, 91.9%, 93.6%, 97.3% and 97.1%, respectively. Concomitant resistance to aminoglycosides, quinolones and aztreonam was also noticed. Presence of any of the bla genes (bla(CTX-M), bla(TEM), and bla(SHV)) was noticed in a total of 28 (38.4%) isolates of the 73 isolates studied. Many isolates demonstrated occurrence of these genes in various combinations. bla(CTX-M), bla(TEM), and bla(SHV) were noticed in 28.8%, 10.9% and 13.7% isolates, respectively. Multiplex PCR in bla(CTX-M) harboring isolates demonstrated the presence of CTX-M-Genogroup-1 and sequencing for the specific CTX-M-type revealed presence of CTX-M-15 type. RAPD typing showed wide diversity in isolates.@*CONCLUSIONS@#This is amongst the premier report describing the simultaneous occurrence of bla(TEM), bla(SHV), and bla(ampC) in Indian Enterobacteriaceae and that wider dissemination of these genes, as demonstrated by diversity of isolates, raises concern and emphasizes a need for extensive search for the presence of these gene pools in Indian subcontinent.
