2 | “ISISI” BARRIERS AS “ANTIDOTES” FOR THE COVID-19 PANDEMIC
“ISISI” as solid barriers (Fig. 1.), namely, [Isolation with Masks, Unit protective clothing, Stay at “home”, and Travel restriction (MUST); Screening and testing; Individual immunity by a healthy lifestyle, for example, a magic and novel “polypill”—“environment-sleep-emotion-exercise-diet” intervention [E(e)SEEDi] (1), bio-agents (chemical agents, convalescent plasma, neutralizing antibody, and Chinese medicine), and vaccination; Social and medical supports; International cooperation and information sharing]. From locals, nations or regions to the globe, these solid barriers are very suitable for not only major virus communicable diseases, which include Avian influenza, Covid-19, Dengue fever, Ebola, Middle East respiratory syndrome (MERS), and Zika fever, but also major bacteria communicable diseases. It’s also termed “antidotes” for the Covid-19 pandemic. Hence, during the pandemic, these barriers should be strengthen so as to combat SARS-CoV-2 and its variants.
Remdesivir and chloroquine as chemical agents were confirmed by basic and clinical studies for antiviral therapy (2, 3). A clinical trial showed that Baricitinib plus Remdesivir for hospitalized adults with Covid-19 have better clinical outcomes and fewer serious adverse events (4). And use of dexamethasone may also lower mortality in hospitalized Covid-19 cases (5). Some chemical agents which have the antiviral role of SARS-CoV-2 are discovered (6). Particularly, new antiviral drugs Merck’s Molnupiravir and Pfizer protease inhibitor Paxlovid can cut Covid-19 hospitalizations and could change the course of the pandemic (7, 8). Traditional Chinese medicine (TCM) for Covid-19, such as Lianhua Qingwen (9), and TCM hot pot consisting of “bark-flower-fruit-grass-leaf-nucleolus-root (BFFGLNR)”, and others, are also effective but need to more clinical evidences. Hence, integration of TCM with western medicine will be better.
Since there are acute antibody responses to SARS-CoV-2, serological testing for IgG and IgM is helpful to the diagnosis of suspected and asymptomatic cases (10). A highly effective neutralizing antibody (NA) found by Chinese scientists (11) is a specific “antidote” of SARS-CoV-2. It acts like a powerful firefighting force and can put out the “raging fire” in human body. Covid-19 convalescent plasma (CCP) treatment is beneficial to patients (12, 13), particularly, it is effective for severe Covid-19 cases (14), it confirms the role of NA for SARS-CoV-2. However, the NA for Covid-19 still needs clinical trials for its reliable efficacy.
Prevention is the best cure. So far, a number of novel Covid-19 vaccines have been developed, clinical trials as well vaccination are being accelerated to do so as to fight against this major viral disease. A study found that circulating SARS-CoV-2-specific CD8+ and CD4+ T cells were identified in ∼70% and 100% of Covid-19 convalescent cases (15), respectively, this adaptive immunity to SARS-CoV-2 supports current vaccine development in the globe.
Animal experiments have also showed DNA vaccine protection against SARS-CoV-2 in nonhuman primates due to elicited NA (16), and confirmed infection with SARS-CoV-2 can result in protective humoral and cellular immune responses against re-exposure (17). Clinical trials confirmed the safety, tolerability, and immunogenicity of a recombinant adenovirus type-5 vectored Covid-19 vaccine developed by Chinese scientists (18, 19). The reported inactivated vaccines, “universal vaccines” (20), and novel mRNA vaccines for SARS-CoV-2 and its variants will offer a new hope for humankind to combat the Covid-19 pandemic (21). In short, “more vaccines, more hope”.