The β-lactams—a large class of diverse compounds—due to their excellent safety profile and broad antimicrobial spectrum are considered to be the most widely used therapeutic class of antibacterials prescribed in human and veterinary clinical practices. This, unfortunately, has also given rise to a continuous increased resistance globally in health care settings as well as in the community due to their permanent selective force driving diversification of the resistance mechanism. Resistance against β-lactams is increasing rapidly as novel β-lactamases, enzymes that degrade β-lactams, are being discovered each day such as recent emergence of extended spectrum β-lactamases (ESBL) that have the ability to inactivate most of the cephalosporins. The complexity and diversity of ESBL are increasing so rapidly that more than 170 variants have thus far been described for only a single genotype, the blaCTX-M-encoding ESBL. This review is to organize all the current updated literature describing genomic features, organization, and mechanism of resistance and mode of dissemination of all known ESBLs.

Background and aimPhylogenetic analysis has led to the classification of hepatitis C virus (HCV) into 1-6 major genotypes. HCV genotypes have different biological properties, clinical outcome and response to antiviral treatment and provide important clues for studying the epidemiology, transmission and pathogenesis. This article deepens the current molecular information about the geographical distribution of HCV genotypes and subgenotypes in population of four provinces of Pakistan. 34 published papers (1996-2011) related to prevalence of HCV genotypes/serotypes and subgenotypes in Pakistan were searched.ResultHCV genotype/s distribution from all 34 studies was observed in 28,400 HCV infected individuals in the following pattern: 1,999 (7.03%) cases of genotype 1; 1,085 (3.81%) cases of genotype 2; 22,429 (78.96%) cases of genotype 3; 453 (1.59%) cases of genotype 4; 29 (0.10%) cases of genotype 5; 37 (0.13%) cases of genotype 6; 1,429 (5.03%) cases of mixed genotypes, and 939 (3.30%) cases of untypeable genotypes. Overall, genotype 3a was the predominant genotype with a rate of 55.10%, followed by genotype 1a, 3b and mixed genotype with a rate of 10.25%, 8.20%, and 5.08%, respectively; and genotypes 4, 5 and 6 were rare. Genotype 3 occurred predominately in all the provinces of Pakistan. Second more frequently genotype was genotype 1 in Punjab province and untypeable genotypes in Sindh, Khyber Pakhtunkhwa and Balochistan provinces.

Epidemiological models have been used extensively to predict disease spread in large populations. Among these models, Susceptible Infectious Exposed Recovered (SEIR) is considered to be a suitable model for COVID-19 spread predictions. However, SEIR in its classical form is unable to quantify the impact of lockdowns. In this work, we introduce a variable in the SEIR system of equations to study the impact of various degrees of social distancing on the spread of the disease. As a case study, we apply our modified SEIR model on the initial spread data available (till April 9, 2020) for the Kingdom of Saudi Arabia (KSA). Our analysis shows that with no lockdown around 2.1 million people might get infected during the peak of spread around 2 months from the date the lockdown was first enforced in KSA (March 25th). On the other hand, with the Kingdom's current strategy of partial lockdowns, the predicted number of infections can be lowered to 0.4 million by September 2020. We further demonstrate that with a stricter level of lockdowns, the COVID-19 curve can be effectively flattened in KSA.

BackgroundHepatitis B Virus (HBV) may progress to serious consequences and increase dramatically beyond endemic dimensions that transmits to or from health care workers (HCWs) during routine investigation in their work places. Basic aim of this study was to canvass the safety of HCWs and determine the prevalence of HBV and its possible association with occupational and non-occupational risk factors. Hepatitis B vaccination coverage level and main barriers to vaccination were also taken in account.ResultsA total of 824 health care workers were randomly selected from three major hospitals of Peshawar, Khyber Pakhtunkhwa. Blood samples were analyzed in Department of Zoology, Kohat University of Science and Technology Kohat, and relevant information was obtained by means of preset questionnaire. HCWs in the studied hospitals showed 2.18% prevalence of positive HBV. Nurses and technicians were more prone to occupational exposure and to HBV infection. There was significant difference between vaccinated and non-vaccinated HCWs as well as between the doctors and all other categories. Barriers to complete vaccination, in spite of good knowledge of subjects in this regard were work pressure (39.8%), negligence (38.8%) un-affordability (20.9%), and unavailability (0.5%).ConclusionsSpecial preventive measures (universal precaution and vaccination), which are fundamental way to protect HCW against HBV infection should be adopted.

AimHigh prevalence of Hepatitis C virus (HCV) has been reported among the dialysis patients throughout the world. No serious efforts were taken to investigate HCV in patients undergoing hemodialysis (HD) treatment who are at great increased risk to HCV. HCV genotypes are important in the study of epidemiology, pathogenesis and reaction to antiviral therapy. This study was performed to investigate the prevalence of active HCV infection, HCV genotypes and to assess risk factors associated with HCV genotype infection in HD patients of Khyber Pakhtunkhwa as well as comparing this prevalence data with past studies in Pakistan.MethodsPolymerase chain reaction was performed for HCV RNA detection and genotyping in 384 HD patients. The data obtained was compared with available past studies from Pakistan.ResultsAnti HCV antibodies were observed in 112 (29.2%), of whom 90 (80.4%) were HCV RNA positive. In rest of the anti HCV negative patients, HCV RNA was detected in 16 (5.9%) patients. The dominant HCV genotypes in HCV infected HD patients were found to be 3a (n = 36), 3b (n = 20), 1a (n = 16), 2a (n = 10), 2b (n = 2), 1b (n = 4), 4a (n = 2), untypeable (n = 10) and mixed (n = 12) genotype.ConclusionThis study suggesting that i) the prevalence of HCV does not differentiate between past and present infection and continued to be elevated ii) HD patients may be a risk for HCV due to the involvement of multiple routes of infections especially poor blood screening of transfused blood and low standard of dialysis procedures in Pakistan and iii) need to apply infection control practice.