The challenges of HdI in case of COVID-19 are: (i) less effectiveness, periodic outbreaks can still occur, (ii) unevenly distributed within a population, clusters of susceptible hosts that frequently contact one another may remain, (iii) the proportion of immunized individuals surpasses the HdI threshold, susceptible individuals will be found in the risk zone for local outbreaks, (iv) nonrelevant infection fatality rate (IFR) and case fatality rate (CFR). Still there is no straightforward, ethical path to reach the goal with HdI in case of COVID-19, due to the societal consequences of achieving it are devastating. A nonuniform COVID-19 case fatality rate (CFR) has been reported across age groups, with the vast majority of deaths occurring among individuals 60 years old or greater. Sex- and ethnicity-specific CFRs suggest that genetic, environmental, and social determinants may affect in susceptibility to COVID-19 and the severity of SARS-CoV-19 infections.
Sodium chloride (NaCl) also called 'table salt' as coating material on the fiber surface of the filtration unit of surgical mask effectively deactivated a number influenza virus species, suggesting a new strategy in the protective measures to avoid primary/secondary infection and transmission of many viruses, including SARS-CoV-19. On the other hand, the natural adsorbents, including clay, charcoal, and clay minerals showed 99.99% adsorption of CoVs. Some minerals that may act against CoVs are selenium, copper, iron, chromium, potassium, zinc, and so on. Moreover, medicinal plants or their derivatives are also evident to act against hCoVs.
The main limiting aspects of this comprehensive review emerge from the studies that have been performed on these drugs that are still only experimental. Many of the studies analyzed included a relatively small number of patients and as a result data that are not statistically significant. That is why many old drugs with a well-known mechanism of action are re-proposed for the treatment of COVID-19. As no vaccine against COVID_19 has been approved yet, vaccine types have not been included in this paper. In addition, this review did not consider the cases of special patients such as the pediatric population and pregnant women, as they are excluded from clinical trials for ethical reasons.
The strength of this review is providing of the recent data with regard to the management of the COVID-19, within the environment in which information is rapidly changing and being made available; and it will be beneficial to health professionals.