scholarly journals Review of COVID-19 vaccine subtypes, efficacy and geographical distributions

2021 ◽  
pp. postgradmedj-2021-140654
Author(s):  
Andre Ian Francis ◽  
Saudah Ghany ◽  
Tia Gilkes ◽  
Srikanth Umakanthan
Keyword(s):  
Herd Immunity ◽  
Damaging Effects

As of 1 May 2021, there have been 152 661 445 Covid-19 cases with 3 202 256 deaths globally. This pandemic led to the race to discover a vaccine to achieve herd immunity and curtail the damaging effects of Covid-19. This study aims to discuss the most recent WHO-approved Covid-19 vaccine subtypes, their status and geographical scheduled updates as of 4 May 2021. The keywords “Covid-19, Vaccines, Pfizer, BNT162b2, AstraZeneca, AZD1222, Moderna, mRNA-1273, Janssen, Ad26.COV2.S” were typed into PubMed. Thirty Two relevant PubMed articles were included in the study. The vaccines discussed are Pfizer/BNT162b2, Moderna Vaccine/mRNA1273, AstraZeneca/AZD122/ChAdOx1 n-CoV-19 and the Janssen vaccines/Ad26.COV2.S, as well as their platforms, trials, limitations and geographical distributions. As of 16 May 2021, the number of countries that have approved the use of the following vaccines is Pfizer in 85, Moderna in 46, Oxford/AstraZeneca in 101, and Janssen in 41.

ADDRESSING THE ISSUE OF СOVID-19, SARS-COV-2 VIRUS AND THE DISEASE

2020 ◽  
Vol 99 (6) ◽  
pp. 15-31
Author(s):  
A.A. Korenkova ◽  
◽  
E.M. Mayorova ◽  
V.V. Bahmetjev ◽  
M.V. Tretyak ◽  
...  
Keyword(s):  
Public Health ◽  
Immune Responses ◽  
Molecular Mechanisms ◽  
Herd Immunity ◽  
Significant Problem ◽  
Prevention Measures ◽  
Optimal Therapy ◽  
The World ◽  
Public Health Challenge ◽  
Coronavirus Infection

The new coronavirus infection has posed a major public health challenge around the world, but new data on the disease raises more questions than answers. The lack of optimal therapy is a significant problem. The article examines the molecular mechanisms of SARS-CoV-2 infection and the pathogenesis of COVID-19, special attention is paid to features of pathological processes and immune responses in children. COVID-19 leads to a wide diversity of negative outcomes, many of which can persist for at least months. Many of the consequences have yet to be identified. SARS-CoV-2 may provoke autoimmune reactions. Reinfection, herd immunity, vaccines and other prevention measures are also discussed in this review.

The Prospect of Herd Immunity to Curb COVID-19 in Bangladesh: A Review

2020 ◽  
Author(s):  
Onamika Rani Sarker ◽  
Sabyasachi Antor Chanda
Keyword(s):  
Herd Immunity

SARS-CoV-2 Seroprevalence Study in Pimpri-Chinchwad, Maharashtra, India Coinciding with Falling Trend – Do the Results Suggest Imminent Herd Immunity?

2020 ◽  
Author(s):  
Amitav Banerjee ◽  
Bhargav Gaikwad ◽  
Atul Desale ◽  
Sudhir L. Jadhav ◽  
Jitendra Bhawalkar ◽  
...  
Keyword(s):  
Herd Immunity ◽  
Seroprevalence Study

In vitro Cytotoxicity and Genotoxicity Analysis of Ten Tannery Chemicals Using SOS/umu Tests and High-content In vitro Micronucleus Tests

2018 ◽  
Vol 21 (4) ◽  
pp. 262-270 ◽  
Author(s):  
Zehao Huang ◽  
Na Li ◽  
Kaifeng Rao ◽  
Cuiting Liu ◽  
Zijian Wang ◽  
...  
Keyword(s):  
Micronucleus Test ◽  
A549 Cells ◽  
Quantitative Structure Activity Relationship ◽  
In Vitro Cytotoxicity ◽  
Cytotoxic Effects ◽  
Qsar Analysis ◽  
Cell Assays ◽  
Micronucleus Tests ◽  
Damaging Effects

Background: More than 2,000 chemicals have been used in the tannery industry. Although some tannery chemicals have been reported to have harmful effects on both human health and the environment, only a few have been subjected to genotoxicity and cytotoxicity evaluations. Objective: This study focused on cytotoxicity and genotoxicity of ten tannery chemicals widely used in China. Materials and Methods: DNA-damaging effects were measured using the SOS/umu test with Salmonella typhimurium TA1535/pSK1002. Chromosome-damaging and cytotoxic effects were determined with the high-content in vitro Micronucleus test (MN test) using the human-derived cell lines MGC-803 and A549. Conclusion: The cytotoxicity of the ten tannery chemicals differed somewhat between the two cell assays, with A549 cells being more sensitive than MGC-803 cells. None of the chemicals induced DNA damage before metabolism, but one was found to have DNA-damaging effects on metabolism. Four of the chemicals, DY64, SB1, DB71 and RR120, were found to have chromosome-damaging effects. A Quantitative Structure-Activity Relationship (QSAR) analysis indicated that one structural feature favouring chemical genotoxicity, Hacceptor-path3-Hacceptor, may contribute to the chromosome-damaging effects of the four MN-test-positive chemicals.

Can Mandated BCG Vaccine Promote herd Immunity against Novel Coronavirus? A Potential Solution at Hand to Tackle Covid-19 Pandemic

2020 ◽  
Vol 16 (1) ◽  
pp. 6-11
Author(s):  
Ashok Arasu ◽  
Pavithra Balakrishnan ◽  
Thirunavukkarasu Velusamy ◽  
Thiagarajan Ramesh
Keyword(s):  
Protective Factor ◽  
Herd Immunity ◽  
Bcg Vaccine ◽  
Intestinal Cells ◽  
Global Public Health ◽  
Wuhan City ◽  
Live Attenuated Vaccine ◽  
Angiotensin Converting Enzyme 2 ◽  
Lung Epithelial ◽  
Novel Coronavirus

The 2019 novel coronavirus (2019-nCoV) infection is an emerging pandemic that poses a severe threat to global public health. This pandemic started from the Wuhan City of Hubei Province in China, and is speculated to have originated from bats and spread among humans with an unknown intermediate transmitter. The virus binds to angiotensin-converting enzyme 2 (ACE2), which is abundantly expressed on various human cells, including lung epithelial and intestinal cells, thereby entering into these cells and causing infection. It is transmitted to other humans through airborne droplets from infected patients. Presently there are no specific treatments or vaccines that are available to curtail the spread of this disease. There are few indirect reports that explain the potential importance of the mandated BCG vaccine as a protective factor against COVID-19. There is a speculation that a live attenuated vaccine (BCG vaccine) can be beneficial against COVID-19 to develop the initial immune response, and can also spread in the community, thereby boosting herd immunity to fight against COVID-19. This review summarizes the conclusions of various reports on the BCG vaccine, and is an attempt to establish BCG-vaccination mediated herd immunity as an effective instant intermediate approach in curbing COVID-19 spread in highly populous countries.

SARS-CoV-2 Biology Insights, Part IV.Antibody-Dependent Enhancement (ADE) and the tricky “Herd Immunity”: narrative review (Preprint)

2020 ◽  
Author(s):  
Laura Lafon-Hughes
Keyword(s):  
Viral Infection ◽  
Viral Entry ◽  
Neutralizing Antibodies ◽  
Vaccine Development ◽  
Whooping Cough ◽  
Common Knowledge ◽  
Herd Immunity ◽  
Life Quality ◽  
Host Cells ◽  
System P

BACKGROUND It is common knowledge that vaccination has improved our life quality and expectancy since it succeeded in achieving almost eradication of several diseases including chickenpox (varicella), diphtheria, hepatitis A and B, measles, meningococcal, mumps, pneumococcal, polio, rotavirus, rubella, tetanus and whooping cough (pertussis) Vaccination success is based on vaccine induction of neutralizing antibodies that help fight the infection (e.g. by a virus), preventing the disease. Conversely, Antibody-dependent enhancement (ADE) of a viral infection occurs when anti-viral antibodies facilitate viral entry into host cells and enhance viral infection in these cells. ADE has been previously studied in Dengue and HIV viruses and explains why a second infection with Dengue can be lethal. As already reviewed in Part I and Part II, SARS-Cov-2 shares with HIV not only 4 sequences in the Spike protein but also the capacity to attack the immune system. OBJECTIVE As HIV presents ADE, we wondered whether this was also the case regarding SARS-CoV-2. METHODS A literature review was done through Google. RESULTS SARS-CoV-2 presents ADE. As SARS, which does not have the 4 HIV-like inserts, has the same property, ADE would not be driven by the HIV-like spike sequences. CONCLUSIONS ADE can explain the failure of herd immunity-based strategies and will also probably hamper anti-SARS-CoV-2 vaccine development. As reviewed in Part I, there fortunately are promising therapeutic strategies for COVID-19, which should be further developed. In the meantime, complementary countermeasures to protect mainly the youth from this infection are presented to be discussed in Part V Viewpoint.

scholarly journals COVID-19 Vaccine Intention among Healthcare Workers in Saudi Arabia: A Cross-Sectional Survey

Vaccines ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 835
Author(s):  
Mohammed Noushad ◽  
Mohammad Zakaria Nassani ◽  
Anas B. Alsalhani ◽  
Pradeep Koppolu ◽  
Fayez Hussain Niazi ◽  
...  
Keyword(s):  
Saudi Arabia ◽  
Healthcare System ◽  
Healthcare Workers ◽  
Vaccine Coverage ◽  
Vaccination Campaign ◽  
Herd Immunity ◽  
Positive Sign ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Public Health Strategies

The COVID-19 pandemic has caused largescale morbidity and mortality and a tremendous burden on the healthcare system. Healthcare workers (HCWs) require adequate protection to avoid onward transmission and minimize burden on the healthcare system. Moreover, HCWs can also influence the general public into accepting the COVID-19 vaccine. Therefore, determining COVID-19 vaccine intention among HCWs is of paramount importance to plan tailor-made public health strategies to maximize vaccine coverage. A structured questionnaire was administered in February and March 2021 among HCWs in Saudi Arabia using convenience sampling, proceeding the launch of the vaccination campaign. HCWs from all administrative regions of Saudi Arabia were included in the study. In total, 674 out of 1124 HCWs responded and completed the survey (response rate 59.9%). About 65 percent of the HCWs intended to get vaccinated. The intention to vaccinate was significantly higher among HCWs 50 years of age or older, Saudi nationals and those who followed the updates about COVID-19 vaccines (p < 0.05). The high percentage (26 percent) of those who were undecided in getting vaccinated is a positive sign. As the vaccination campaign gathers pace, the attitude is expected to change over time. Emphasis should be on planning healthcare strategies to convince the undecided HCWs into accepting the vaccine in order to achieve the coverage required to achieve herd immunity.

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