A novel coronavirus (nCoV) spillover event, with its epicenter in Wuhan, People's Republic of China, has emerged as a public health emergency of international concern. This began as an outbreak in ...December 2019, and till February 28, 2020, there have been 83,704 confirmed cases of novel coronavirus disease 2019 (COVID-19) globally, with 2,859 deaths, resulting in an overall case fatality rate of 3.41 per cent (95% confidence interval 3.29-3.54%). By this time (February 28, 2020) 58 countries or territories and one international conveyance (Diamond Princess Cruise Ship) were affected. As a part of the global response to manage and contain the pandemic, major emphasis was placed on generating research intelligence to guide evidence-based responses to contain the virus, which was named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), owing to its genetic similarities with the SARS virus. This review summarizes the emerging evidence which can help guide the public health response, particularly in India. Key areas have been identified in which research needs to be conducted to generate critical intelligence for advising prevention and control efforts. The emergence of SARS-CoV-2 has once again exposed the weaknesses of global health systems preparedness, ability to respond to an infectious threat, the rapidity of transmission of infections across international borders and the ineffectiveness of knee-jerk policy responses to emerging/re-emerging infectious disease threats. The review concludes with the key learning points from the ongoing efforts to prevent and contain COVID-19 and identifies the need to invest in health systems, community-led response mechanisms and the need for preparedness and global health security.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
•Respiratory viruses mutate and evolve rapidly to cause epidemics and pandemics.•WHO-GISRS is a global surveillance mechanism for influenza and respiratory viruses.•ILI and SARI surveillance led by ...WHO NICs remains weak in many parts of the world.•Surveillance through NICs must be strengthened for timely outbreak detection.•We have suggested strategies to strengthen surveillance through NICs.
The global influenza surveillance and response system (GISRS), coordinated by the World Health Organization (WHO), is a global framework for surveillance of influenza and other respiratory viruses, data collection, laboratory capacity building, genomic data submission and archival, standardization, and calibration of reagents and vaccine strains, production of seasonal influenza vaccines and creating a facilitatory regulatory environment for the same.
WHO-designated national influenza centers (NICs) are entrusted with establishing surveillance in their respective countries. National and subnational surveillance remains weak in most parts of the world because of varying capacities of the NICs, lack of funds, poor human and veterinary surveillance mechanisms, lack of intersectoral coordination, and varying commitments of the local government.
As influenza viruses have a wide variety of nonhuman hosts, it is critical to strengthen surveillance at local levels for timely detection of untypable or novel strains with potential to cause epidemics or pandemics. In this article, we have proposed possible strategies to strengthen and expand local capacities for respiratory virus surveillance through the designated NICs of the WHO.
Proposed mechanism for strengthening local or subnational respiratory virus surveillance and response. Display omitted
We present our experimental results for the effect of bulk-soluble surfactants on the buoyancy-driven motion of an air bubble rising in square and rectangular channels filled with an immiscible ...liquid. Glycerol and glycerol–water solutions were chosen as the bulk fluid, and Triton X-100 and Aerosol-OT were used as surfactants. Bulk surfactant concentrations below as well as above the critical micelle concentration were considered. Even at very low bulk surfactant concentrations where the equilibrium surface tension did not change, bubbles rising through the surfactant solutions showed reduced mobility, especially for small bubbles. At larger surfactant concentrations, bubbles of all sizes showed lower terminal velocities. At a large enough bulk surfactant concentration, two peaks were seen in the velocity-volume curve. Increasing the bulk surfactant concentrations above the critical micelle concentration increased the mobility of the bubbles but still showed two peaks in the velocity-volume curve.
As the global severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic expands, genomic epidemiology and whole genome sequencing are being used to investigate its transmission and ...evolution. Against the backdrop of the global emergence of “variants of concern” (VOCs) during December 2020 and an upsurge in a state in the western part of India since January 2021, whole genome sequencing and analysis of spike protein mutations using sequence and structural approaches were undertaken to identify possible new variants and gauge the fitness of the current circulating strains. Phylogenetic analysis revealed that newly identified lineages B.1.617.1 and B.1.617.2 were predominantly circulating. The signature mutations possessed by these strains were L452R, T478K, E484Q, D614G and P681R in the spike protein, including within the receptor-binding domain (RBD). Of these, the mutations at residue positions 452, 484 and 681 have been reported in other globally circulating lineages. The structural analysis of RBD mutations L452R, T478K and E484Q revealed that these may possibly result in increased ACE2 binding while P681R in the furin cleavage site could increase the rate of S1-S2 cleavage, resulting in better transmissibility. The two RBD mutations, L452R and E484Q, indicated decreased binding to select monoclonal antibodies (mAbs) and may affect their neutralization potential. Further in vitro/in vivo studies would help confirm the phenotypic changes of the mutant strains. Overall, the study revealed that the newly emerged variants were responsible for the second wave of COVID-19 in Maharashtra. Lineage B.1.617.2 has been designated as a VOC delta and B.1.617.1 as a variant of interest kappa, and they are being widely reported in the rest of the country as well as globally. Continuous monitoring of these and emerging variants in India is essential.
We present a technique for the continuous interphase synthesis of metal oxide nanoparticles using a droplet flow reactor. Conducting the synthesis reaction inside droplets of controlled volume offers ...several advantages, such as eliminating temperature and concentration gradients inside the reactor as well as preventing reactor fouling. The synthesis reagents are initially located in separate phases, and reagent addition is accomplished through diffusion from the bulk phase to the droplet phase. In this work, the technique is demonstrated by synthesizing zinc oxide nanoparticles inside aqueous droplets containing zinc acetate in a bulk stream of sodium hydroxide in 1-octanol. This flow synthesis of zinc oxide nanoparticles provides more control of the nanoparticle morphology and has a narrow particle size distribution as compared to that of a batch reactor. The size and morphology of the nanoparticles are shown to be easily controlled from 41 to 62 nm by varying zinc acetate and sodium hydroxide concentration, reaction temperature, and residence time. Spherical as well as platelike shapes of zinc oxide nanoparticles are seen for the ranges of parameters studied. This technique can be used to synthesize a variety of metal oxide nanoparticles of controllable size.
Introduction
Cervical cancer has been considered as one of the most common cancers in women (15–44 years) globally, but the advent of the human papilloma virus (HPV) vaccine has raised the ...anticipation that eradication of cervical carcinoma might be achieved in the near future as several prophylactic cervical carcinoma vaccines have already been currently licensed in various countries. Countries should devise strategies, practices and policies to attain and sustain higher levels of HPV immunization coverage as still 68% countries have introduced HPV vaccine in their national immunization programs even after 17 years following the licensure of the first prophylactic HPV vaccine.
Methodology
A comprehensive literature analysis was conducted using various databases and search engines, to include the most relevant research articles and data available and critically discussed the operational gaps that need to be answered to achieve adequate coverage of HPV vaccination.
Results
The present review highlights the existing HPV vaccination strategies, unmet needs and challenges needed to be addressed for proper implementation framework as well as the collaborations required to achieve decent vaccination coverage. Well‐coordinated vaccination strategy with focus on adolescent girls and if possible, boys can lead to dramatic impact on disease reduction around the world.
Practices and policies related to human papilloma virus (HPV) vaccination need to be improved to achieve better vaccination coverage. The present review highlights the existing HPV vaccination strategies, unmet needs and challenges needed to be addressed for proper implementation framework as well as the collaborations required to achieve decent vaccination coverage.
We present results of our numerical study of the effect of surfactants on buoyancy-driven motion of drops in a tube at intermediate Reynolds numbers. The drop and bulk phases are treated as ...incompressible Newtonian fluids and simulated using a front-tracking method. The steady shapes and velocity–volume curves for drops ranging in drop size from 0.2 to 1.3 of tube radius are determined numerically. At small Bond numbers, the velocity–volume curve shows a maximum before the velocity plateaus for large drops. As the Bond number increases, the maximum in the velocity–volume curve disappears with elongated, more streamlined drop shapes consistent with previous experimental studies. For increasing Weber numbers, the rear of the drop shows a flattening followed by the development of a negative curvature. Surfactants are modeled using a Langmuir equation of state in the adsorption–desorption limit and the effect of surfactant mass transfer, fractional coverage of surfactants, and the interfacial Peclet number on the velocity–volume curve is determined. Marangoni stress generated due to the non-uniform distribution of surfactants at the interface reduces drop mobility. Reduced drop mobility is more prominent for drop sizes that are comparable to the tube diameter and is maximum when mass transfer to and from the interface is inhibited. As the fractional coverage of soluble surfactants, or the interfacial Peclet number increases, larger Marangoni stresses are generated along the interface that lead to greater retardation of the drop motion.
•Buoyancy-driven motion of drops with inertial and surfactant effects are simulated.•Flattening and negative curvature seen at rear of the drop for large Weber numbers.•Reduced drop mobility with surfactants is prominent for intermediate-sized drops.•Effect of mass transfer and fractional coverage of surfactants were determined.
The COVID-19 pandemic is a global health crisis that poses a great challenge to the public health system of affected countries. Safe and effective vaccines are needed to overcome this crisis. Here, ...we develop and assess the protective efficacy and immunogenicity of an inactivated SARS-CoV-2 vaccine in rhesus macaques. Twenty macaques were divided into four groups of five animals each. One group was administered a placebo, while three groups were immunized with three different vaccine candidates of BBV152 at 0 and 14 days. All the macaques were challenged with SARS-CoV-2 fourteen days after the second dose. The protective response was observed with increasing SARS-CoV-2 specific IgG and neutralizing antibody titers from 3
-week post-immunization. Viral clearance was observed from bronchoalveolar lavage fluid, nasal swab, throat swab and lung tissues at 7 days post-infection in the vaccinated groups. No evidence of pneumonia was observed by histopathological examination in vaccinated groups, unlike the placebo group which exhibited interstitial pneumonia and localization of viral antigen in the alveolar epithelium and macrophages by immunohistochemistry. This vaccine candidate BBV152 has completed Phase I/II (NCT04471519) clinical trials in India and is presently in phase III, data of this study substantiates the immunogenicity and protective efficacy of the vaccine candidates.
•Ebola virus (EBOV) outbreak is recognized as public health emergency of international concern.•It poses global threat due to excessive international travel without proper investigations.•Past ...outbreaks and experiences learned facilitated delineating the steps toward preparedness of developing countries.•This review will help upgrading the preparedness plan in resource limited settings to contain future EBOV outbreaks.
Ebola virus (EBOV); a public health emergency of international concern,is known to pose threat of global outbreaks. EBOV has spread in African continent and due to unchecked international travel, importation of cases has been reported in different countries. In this alarming scenario, developing countries need to evaluate and upgrade their preparedness plan to contain the spread of EBOV. The present review lays down the updated preparedness plan for developing countries to contain future EBOV outbreaks.
The literature on EBOV outbreaks and preparedness strategies reported were searched on Pubmed and Google Scholar using the MeSH terms such as "Ebola virus disease, Epidemic, Outbreak, Imported case, Preparedness, Public health interventions" combined with Boolean operator (OR) for the period of 2011–2020. Additionally, World Health organization (WHO) and Centers for Disease Control & Prevention (CDC) websites were searched for the guidelines, reports, containment strategies, containment plan of countries, actions taken by countries and international partners, etc.
The present review analyzed the EBOV outbreaks between 2011–2020 and containment strategies used by the affected countries. Based on the lessons learned from EBOV outbreaks and personal experience in infectious disease management, we have recommended a preparedness and response plan for EBOV containment in developing countries.
Developing countries are particularly vulnerable to major outbreaks of EBOV due to increased international travel and unchecked transmission. The recommended preparedness plan will help developing counties to contain EBOV outbreaks in future.
PDF
