**6. Preventive measures to control the spread of the infection**

Since there is limited availability of effective treatment for COVID-19, therefore, currently, *prevention* is used as a vital step in controlling the (community) spread of the infection. However, some unique features of the disease like a transmission from asymptomatic people, long incubation period, and infectivity in the incubation period even before the onset of symptoms, prolonged illness, and transmission after recovery, etc., make the preventive measures really more challenging [18]. First of all, extensive measures should be taken to limit human to human transmission with an emphasis on susceptible populations like healthcare providers and older people to prevent further transmission amplification and spread [42]. The second essential step must be the facilitation of advanced health surveillance systems along with rapid diagnostic facilities for the identification of cases. It should be followed by quarantine or isolation when necessary, with intensive care for patients and contact tracing for preventing further transmission by contacts who are infected [43]. Patients should be isolated in well ventilated room with regular decontamination, and they should follow cough and sneeze hygiene, practice hand hygiene and should be asked to wear surgical masks to prevent infection spreading. The healthcare workers attending the patients should be advised to use personal protective equipment (PPE) like gloves, N95 masks, goggles, protective suits, etc. The use of masks by healthy people though not recommended by WHO, owing to the recent finding by Japanese scientists that simple conversations in close proximity without coughs and sneeze could spread the virus through micro-droplets, it is advisable to wear masks, particularly in crowded public places [44]. Owing to the community spread nature of the virus, the government's action to ban mass gatherings is an important preventive step and locking down cities, states, provinces as part of

the action plan of many governments, including India, the US, European Union, etc., will definitely be beneficial in flattening the pandemic. Physical contact with inanimate objects should be avoided since coronaviruses can remain infectious on these surfaces for up to 9 days, however, surface decontamination with ethanol (> 70%) or 0.1% sodium hypochlorite can significantly reduce the virus infectivity even within 1 min exposure time [45]. The public should avoid non-essential travel to places with ongoing transmission and the countries should strictly implement preventive measures like travel screenings and quarantining of the travelers to control further spread of the infection. In countries with resource limitations, to triage a large number of cases, the proposed simple screening algorithm by Ayebare et al. (2020), as shown in **Figure 4** can be followed for effective infection prevention and control [46].

International collaborations and co-operations are highly essential to minimize social as well as economic disruptions [43]. The government's strategy for timely education and training of hospital staff and health care providers along with awareness and counseling to the general public about the risks of COVID-19 are absolutely necessary for minimizing the spread of the infection and managing an economic downturn. However, during this crisis, personal rather than government

**Figure 4.** *Outline of infection prevention and control (IPC) strategies.*



**Table 1.**

*Showing developed vaccine details for Covid-19 infection.*

action might be most important and individual behavior will definitely play a crucial role in infection prevention and control the spread of COVID-19. To date some of the countries have approved many anti-viral drugs as pharmacological treatment strategies for COVID-19. However, some approved COVID-19-specific vaccines are available (**Table 1**). Several companies have developed various vaccine candidates for human CoV infections which are in the clinical trial stage [47].

### **7. Future challenges in controlling the global pandemic**

From the end of July 2020, an increase in new cases of SARS-CoV-2 infections was appeared in the different geographical territories of the European Union, confirmed about the origin of the second wave of outbreaks of these infectious diseases. On September 20, a new variant type of SARS-CoV-2, called B117, was first time identified in the United Kingdom (UK). Also, In December 2020, an unexpected rise in reported COVID-19 cases was observed due to the emergence of a new variant of SARS-CoV-2 (B.1.351) in South Africa. However, it was observed that that B117 is far more transmissible with comparatively less fatality rate [48–51]. Hence, it is important to correlate the mutation of the virus as well as the degree of pathogenicity. The existence of

genetic diversity and specific mutations in the genome of SARS-CoV-2 and the virulence property has been investigated by Abdullahi, et al. In this work, they focused on the mutations of the non-structural proteins (NSPs) such as nsp 2 and nsp 3, Spike protein and RNA-dependent RNA polymerase (RdRp). The spike protein is the key determining factor for the evolution, virulence and transmission [52]. Similarly, the enhanced infection property and pathogenicity in case of SARS-CoV-2 is related to mutation at S-protein receptor-binding domain, has been studied by Padhi and Tripathi [53]. To address the significance of mutation to infection, Yao et al. conducted an experimental work by considering eleven numbers of SARS-CoV-2 viral isolates and observed that the mutations are directly related to the increase in viral load as well as a cytopathic effect [54]. Bakhshandeh et al., emphasized that the gradual accumulation of the genomic mutation in SARS-CoV-2 are having a crucial role in genetic variability of the virus. This helps the virus to escape from the host cell immunity and converts the strain in to a drug resistance virus with more deadly behavior [55]. Another recent study has uncovered that the rate of infection of novel corona virus is not only due to the mutation of the viral genome but also associated with host genetics, the genetic and epigenetic variations of the human population. For example, the ACE2 gene variation might be the key genetic factor for SARS-CoV-2 infection that facilitates the virus entry into human cells [56].

Currently, several strategies are being followed, such as contact tracing of infected people, enforcing the social distancing, maintaining the quarantine, and restricted mobility of people and use of disinfectant for self-protection purpose. However, none of these methods have proved to be effective in controlling the global pandemic caused by COVID-19. Usually, there are three basic areas that is to be emphasized more for the best control of the global pandemic [57–64].


In order to protect the human population and in the limited effective treatment strategy for COVID-19 infection, the implementation of new and effective online technologies in different sectors is desirable. These technologies will help the people in the timely response and control of epidemics in the areas of public training, education, medication, including digital surveillance systems, telemedicine, rapid identification and diagnosis devices, and prediction about the future infection.
