COVID-19 Pandemic: A Compressive Review on Gender, Herd Immunity, and Physiological Mechanisms

Herd Immunity against Coronavirus: A Review

The severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) has spread exponentially, leading to an alarming number of deaths worldwide. A devastating effect has been observed in susceptible populations. Our body's immune system plays a very important role in fighting against the diseases. The principle of herd immunity (also known as population immunity), which has found its way into science and has been in the limelight, is the most widely recognised among all. It is an indirect defence against infectious diseases when a community has gained immunity, either through vaccines or through prior infection. Herd immunity against COVID-19 must be achieved to reduce the transmission of disease and save lives. Therefore, this review provides a comprehension of the role of immunity, with a special emphasis on herd immunity against COVID-19, and the ways to attain herd immunity in India have also been discussed.

Factors Associated with Parental Acceptance of COVID-19 Vaccination: A Multicenter Pediatric Emergency Department Cross-sectional Analysis

Study objective

During the delta surge of the COVID-19 pandemic in 2021, we sought to identify characteristics and beliefs associated with COVID-19 vaccination acceptance in parents of pediatric emergency department (ED) patients.

Methods

We conducted a cross-sectional survey-based study of the parents of children aged 3 to 16 years presenting to 1 of 9 pediatric EDs from June to August 2021 to assess the parental acceptance of COVID-19 vaccines. Using multiple variable regression, we ascertained which factors were associated with parental and pediatric COVID-19 vaccination acceptance.

Results

Of 1,491 parents approached, 1,298 (87%) participated, of whom 50% of the parents and 27% of their children aged 12 years or older and older were vaccinated. Characteristics associated with parental COVID-19 vaccination were trust in scientists (adjusted odds ratio [aOR] 5.11, 95% confidence interval [CI] 3.65 to 7.15), recent influenza vaccination (aOR 2.66, 95% CI 1.98 to 3.58), college degree (aOR 1.97, 95% CI 1.36 to 2.85), increasing parental age (aOR 1.80, 95% CI 1.45 to 2.22), a friend or family member hospitalized because of COVID-19 (aOR 1.34, 95% CI 1.05 to 1.72), and higher income (aOR 1.60, 95% CI 1.27 to 2.00). Characteristics associated with pediatric COVID-19 vaccination (children aged ≥12 years) or intended COVID-19 pediatric vaccination, once approved for use, (children aged <12 years) were parental trust in scientists (aOR 5.37, 95% CI 3.65 to 7.88), recent influenza vaccination (aOR 1.89, 95% CI 1.29 to 2.77), trust in the media (aOR 1.68, 95% CI 1.19 to 2.37), parental college degree (aOR 1.49, 95% CI 1.01 to 2.20), and increasing parental age (aOR 1.26, 95% CI 1.01 to 1.57).

Conclusion

Overall COVID-19 vaccination acceptance was low. Trust in scientists had the strongest association with parental COVID-19 vaccine acceptance for both themselves and their children.

Viral RNA in City Wastewater as a Key Indicator of COVID-19 Recrudescence and Containment Measures Effectiveness

In recent years, and more specifically at the beginning of the COVID-19 crisis, wastewater surveillance has been proposed as a tool to monitor the epidemiology of human viral infections. In the present work, from July to December 2020, the number of copies of SARS-CoV-2 RNA in Marseille's wastewater was correlated with the number of new positive cases diagnosed in our Institute of Infectious Disease, which tested about 20% of the city's population. Number of positive cases and number of copies of SARS-CoV-2 RNA in wastewater were significantly correlated (p = 0.013). During the great epidemic peak, from October to December 2020, the curves of virus in the sewers and the curves of positive diagnoses were perfectly superposed. During the summer period, the superposition of curves was less evident as subject to many confounding factors that were discussed. We also tried to correlate the effect of viral circulation in wastewater with containment measures, probably the most unbiased correlation on their potential inflection effect of epidemic curves. Not only is this correlation not obvious, but it also clearly appears that the drop in cases as well as the drop in the viral load in the sewers occur before the containment measures. In fact, this suggests that there are factors that initiate the end of the epidemic peak independently of the containment measure. These factors will therefore need to be explored more deeply in the future.