Recurring food source-based Listeria outbreaks in the United States: An unsolved puzzle of concern?

Recurring Listeria outbreaks in the United States is a growing public healthcare concern. Although no associated reported death, 17 were hospitalized out of the 18 reported illnesses in the recent outbreak in 15 US states. The United States has experienced about 30 Listeria outbreaks in the last decade with 524 Listeriosis cases and 80 deaths. The identified origin were ice cream, leafy greens, mushroom, meat slice, dairy products like cheese, packaged salads, cooked chicken, hard-boiled egg, pork product, frozen vegetable, raw milk, packaged caramel apple, bean sprout and soya products. Although rare, Listeria may lead to serious illness (invasive listeriosis) or death. Listeriosis is critically harmful and medically complicated, especially in the pregnant, the old above 65 years and in the immunocompromised. It could cause premature birth, miscarriage or even neonatal death. Hospitalization is often necessary in the geriatric, being fatal at times. Among Listeria sp., Listeria monocytogenes is often human infection-associated. It is a gram-positive, non-sporulating, motile bacillus opportunistic pathogen. Food-borne listeriosis is often associated with frozen foods due to its ability to thrive at low temperatures. Hypervirulent strains of L. monocytogenes with an ability to infect the respiratory system (the lungs) was recently reported in the coronavirus disease-19 patients during the pandemic. L. monocytogenes seemed to have developed antimicrobial resistance to ciprofloxacin and meropenem, possibly acquired through the food chain. An early onset of listeriosis in the newborn is evident in the first 7 days postparturition. As the bacteria colonize the genitourinary tract, majority of such cases result from teratogenic transfer during vaginal delivery. Premature newborns, neonates born outside healthcare facilities and low-birth-weight babies were increasingly predisposed to an early onset of listeriosis. Listeria outbreaks were earlier reported in South Africa, Australia and Europe, with an unclear origin of the outbreaks. Social media updates about such outbreaks, the most likely food source, and measures to self-protect are suggested as preventive measures. The article deals on various such aspects related to listeriosis primarily originating from food, to ensure better public healthcare and human wellness.

Global health concern on the rising dengue and chikungunya cases in the American regions: Countermeasures and preparedness.

Background and Aim: Severe morbidity and mortality due to seasonal infectious diseases are common global public health issues. Vector-borne viral illnesses like dengue and chikungunya overload the healthcare systems leading to critical financial burden to manage them. There is no effective drug or vaccine currently available to control these two diseases. Methods: The review was formulated by incorporating relevant reports on chikungunya and dengue in the Americas regions through a comprehensive search of literature that were available on dedicated scientific publication portals such as PubMed, ScienceDirect, and Web of Science. Results: The strategies of public health administrations to control largely the mosquito vectors during tropical monsoon seem to be effective. Yet, it seems practically impossible to completely eliminate them. The mosquito vector disseminates the virus via transovarian route thereby internalising the virus through generations, a reason behind reappearing and recurring outbreaks. The numerous factors associated with industrialisation, urbanisation, population density, and easy transboundary movements appear to have contributed to the spread of vectors from an endemic region to elsewhere. Conclusion: The article made a state-of-affair comprehensive analysis of the rising dengue and chikungunya cases in the tropics, particularly the tropical Americas, as a human health concern, the countermeasures undertaken and the overall preparedness. The viral transmission is a hard situation to tackle as the vector survives in diverse temperature and ecology, is resistant to insecticides, and the unavailability of drugs. Better vector-control measures and improved understanding of the reemerging arboviral infections could offer an extended reaction time to counter outbreaks, and minimise associated morbidity/mortality.

COVID-19 vaccines and their underbelly: Are we going the right way?

Background: Historically, a critical aetiological agent of health concern stays till eternity after its discovery, so shall it be with the COVID-19 outbreak. It has transformed human life to a 'new normal' with huge tolls on the social, psychological, intellectual and financial spheres. Aim: This perspective aimed to collate numerous reported COVID-19 vaccine-associated adverse events and the predisposing factors. It focussed on the efficacy of mix-n-match (cocktail) vaccines to effectively counter COVID-19 infection to facilitate future research and possible interventions. Material and Methods: Databases like Scopus, Pubmed and the Web-of-science were searched for published literature on 'adverse events associated with COVID-19 vaccine'. The reports and updates from health agencies like the WHO and CDC were also considered for the purpose. The details with respect to the adverse events associated with COVID-19 vaccination and the predisposing factors were compiled to obtain insights and suggest possible future directions in vaccine research. Results: India stood strong to manage its health resources in time and turned into a dominant global vaccine supplier at a time when healthcare infrastructure of many countries was still significantly challenged. Developing indigenous vaccines and the vaccination drive in India were its major achievements during the second and the subsequent COVID-19 waves. The fully indigenous Covaxin vaccine, primarily as an emergency intervention, was successfully rapidly launched. Similar such vaccines for emergency use were developed elsewhere as well. However, all of these reached the marketplace with a 'emergency use only' tag, without formal clinical trials and other associated formalities to validate and verify them as these would require much longer incubation time before they are available for human use. Discussion: Many adverse events associated with either the first or the second/booster vaccination doses were reported. Evidently, these associated adverse events were considered as 'usually rare' or were often underreported. Without the additional financial or ethical burden on the vaccine companies, fortunately, the Phase IV (human) clinical trials of their manufactured vaccines are occurring by default as the human population receives these under the tag 'emergency use'. Thus, focused and collaborative strategies to unveil the molecular mechanisms in vaccine-related adverse events in a time-bound manner are suggested. Conclusion: Reliable data particularly on the safety of children is lacking as majority of the current over-the-counter COVID-19 vaccines were for emergency use. Many of these were still in their Phase III and Phase IV trials. The need for a mutant-proof, next-gen COVID-19 vaccine in the face of vaccine-associated adverse events is opined.

COVID-19 Era and the Constantly Reemerging Novel SARS-CoV-2 Variants Calls for Special Attention for the Geriatrics: A Real Challenge.

Global public health is significantly challenged due to the continuing COrona VIrus Disease 2019 (COVID-19) outbreak brought forth by the severe Acute Respiratory Syndrome Corona Virus-2 (SARS-CoV-2) [...].

Need of booster vaccine doses to counteract the emergence of SARS-CoV-2 variants in the context of the Omicron variant and increasing COVID-19 cases: An update.

The emergence of different variants of SARS-CoV-2, including the Omicron (B.1.1.529) variant in November 2021, has resulted in a continuous major health concern at a global scale. Presently, the Omicron variant has spread very rapidly worldwide within a short time period. As the most mutated variant of SARS-CoV-2, Omicron has instilled serious uncertainties on the effectiveness of humoral adaptive immunity generated by COVID-19 vaccination or an active viral infection as well as the protection provided by antibody-based immunotherapies. Amidst such high public health concerns, the need to carry out booster vaccination has been emphasized. Current evidence reveals the importance of incorporating booster vaccination using several vaccine platforms, such as viral vector- and mRNA-based vaccines, as well as other platforms that are under explorative investigations. Further research is being conducted to assess the effectiveness and durability of protection provided by booster COVID-19 vaccination against Omicron and other SARS-CoV-2 variants.

Computational studies on potential new anti-Covid-19 agents with a multi-target mode of action.

A compound that could inhibit multiple targets associated with SARS-CoV-2 infection would prove to be a drug of choice against the virus. Human receptor-ACE2, receptor binding domain (RBD) of SARS-CoV-2 S-protein, Papain-like protein of SARS-CoV-2 (PLpro), reverse transcriptase of SARS-CoV-2 (RdRp) were chosen for in silico study. A set of previously synthesized compounds (1-5) were docked into the active sites of the targets. Based on the docking score, ligand efficiency, binding free energy, and dissociation constants for a definite conformational position of the ligand, inhibitory potentials of the compounds were measured. The stability of the protein-ligand (P-L) complex was validated in silico by using molecular dynamics simulations using the YASARA suit. Moreover, the pharmacokinetic properties, FMO and NBO analysis were performed for ranking the potentiality of the compounds as drug. The geometry optimizations and electronic structures were investigated using DFT. As per the study, compound-5 has the best binding affinity against all four targets. Moreover, compounds 1, 3 and 5 are less toxic and can be considered for oral consumption.