A Comprehensive Review on the Current Vaccines and Their Efficacies to Combat SARS-CoV-2 Variants.

Since the first case of Coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 2019, SARS-CoV-2 infection has affected many individuals worldwide. Eventually, some highly infectious mutants-caused by frequent genetic recombination-have been reported for SARS-CoV-2 that can potentially escape from the immune responses and induce long-term immunity, linked with a high mortality rate. In addition, several reports stated that vaccines designed for the SARS-CoV-2 wild-type variant have mixed responses against the variants of concern (VOCs) and variants of interest (VOIs) in the human population. These results advocate the designing and development of a panvaccine with the potential to neutralize all the possible emerging variants of SARS-CoV-2. In this context, recent discoveries suggest the design of SARS-CoV-2 panvaccines using nanotechnology, siRNA, antibodies or CRISPR-Cas platforms. Thereof, the present comprehensive review summarizes the current vaccine design approaches against SARS-CoV-2 infection, the role of genetic mutations in the emergence of new viral variants, the efficacy of existing vaccines in limiting the infection of emerging SARS-CoV-2 variants, and efforts or challenges in designing SARS panvaccines.

Overview of hepatitis C infection, molecular biology, and new treatment.

The World Health Organization estimates that 71 million people worldwide have chronic hepatitis C viral infection. A major challenge is overall lack of public awareness of hepatitis C, particularly among infected people of their infection status. Chronic hepatitis C infection is associated with advanced liver disease, is the main cause of hepatocellular carcinoma and causes many extra-hepatic manifestations. The existence of seven viral genotypes complicates targeting of treatment. Recent years have seen the approval of many direct acting antivirals targeted at hepatitis C virus non-structural proteins. These have revolutionized therapy as they allow achievement of extremely high sustained virologic responses. Of great significance is the development of pan-genotypic drug combinations, including the NS3/4A-NS5A inhibitor combinations sofosbuvir-velpatasvir and glecaprevir-pibrentasvir. However, resistance-associated mutations can result in failure of these treatments in a small number of patients. This, combined with the high costs of treatment, highlights the importance of continued research into effective anti-hepatitis C therapies, for example aimed at viral entry. Recent developments include identification of the potential of low-cost anti-histamines for repurposing as inhibitors of hepatitis C viral entry. In this review we focus on molecular biology of hepatitis C virus, and the new developments in hepatitis C treatment.

ESBL expression and antibiotic resistance patterns in a hospital in Saudi Arabia: Do healthcare staff have the whole picture?

BACKGROUND: We analyse the distribution of ESBL infections in Dammam Medical Complex, Eastern Province, Saudi Arabia with respect to patient demographics, wards, infection site, bacterial species, and antibiotic resistance. We also gauged hospital staff understanding of ESBLs, the procedures in place to identify, treat and infections containing. METHODS: Hospital records from 2016 were analysed and 352 ESBL from several samples types were identified using VITEK® 2 system and by phenotypic confirmation using a disk diffusion test. HCWs attitudes and knowledge were assessed using a paper questionnaire. RESULTS: The percentage of ESBL isolates were Klebsiella pneumoniae(n=148; 42.1%) or Escherichia coli(n=176; 50%), Proteus mirabilis(n=7; 2%), Morganella morganii(n=13; 3.7%), Enterobacter (n=7; 2%) and Citrobacter freundii (n=1; 0.3%). Overall tigecycline susceptibility was 82.2%, however P. mirabilis and M. morganii isolates were uniformly resistant and K. pneumoniae susceptibility levels were significantly lower than for E. coli in urine samples (72.3% v 100%; Chi square=13.76, p=0.0002); for blood samples there was also apparently higher resistance among K. pneumoniae isolates. Overall susceptibility to the carbapenems imipenem, meropenem and ertapenam was high. There were overall high levels of uncertainty among healthcare workers on hospital policies on reporting or prescribing with respect to ESBL-expressing infections. CONCLUSIONS: ESBL control strategies should consider variations among sample types, wards, and antibiotic resistance variability. There is a need to specifically address staff training and communication procedures for infection prevention and control with respect to ESBLs.

The rise of pneumonic plague in Madagascar: current plague outbreak breaks usual seasonal mould.

Madagascar has just emerged from the grip of an acute urban pneumonic plague outbreak, which began in August 2017, before the usual plague season of October-April and outside the traditional plague foci in the northern and central highlands. The World Health Organization reported a total of 2417 confirmed, probable and suspected cases, including 209 deaths between 1 August and 26 November 2017. The severity and scope of this outbreak, which has affected those in higher socioeconomic groups as well as those living in poverty, along with factors including the potential for use of multi-drug-resistant strains of plague in bioterrorism, highlights the ongoing threat posed by this ancient disease. Factors likely to have contributed to transmission include human behaviour, including burial practices and movement of people, poor urban planning leading to overcrowding and ready transmission by airborne droplets, climatic factors and genomic subtypes. The outbreak demonstrates the importance of identifying targeted pneumonic plague therapies and of developing vaccines that can be administered in planned programmes in developing countries such as Madagascar where plague is endemic. The dominance of pneumonic plague in this outbreak suggests that we need to focus more urgently on the danger of person-to-person transmission, as well as the problem of transmission of plague from zoonotic sources.