Sourav Mukherjee April 8, 2020
Coronaviruses (CoVs) create various types of diseases like respiratory, enteric, renal, and neurological disorders by affecting humans as well as animals. Severe acute respiratory syndrome-related coronavirus (SARS-CoV) initially appeared in people in 2002-2003, affected above 8000 people, and resulting in approximately 800 deaths[1, 2]. Middle East respiratory syndrome coronavirus (MERS-CoV), a genealogy C beta-CoV, was causing a severe respiratory syndrome in 2012. A novel coronavirus, called SARS-CoV-2 (COVID-19), was detected in sufferers with severe pneumonia in Wuhan, China, in December 2019. On 11th March 2020, WHO declared that COVID-19 could be identified as a pandemic and also mentioned that this is the first pandemic caused by a coronavirus( Source: WHO). According to WHO, the total number of confirmed cases of COVID-19 is 1,056,159 and resulting in 57,206 deaths in entire 208 Countries, areas, or territories with cases (Updated: 4 April 2020, 23:48 GMT+5:30). Few essential characteristics of COVID-19 are mentioned below-
- All coronaviruses encode a spike glycoprotein (S), which attaches to the host-cell receptor, followed by mediating membrane fusion as well as viral incorporation and resulting in the antibody neutralization in our body.
- Trimeric S protein is consists of monomers of nearly 180 kDa and S1, S2 are two subunits of it which helps in mediating addition and membrane fusion, sequentially. N-terminal domain (NTD) and C-terminal domain (C-domain) are the two self-governing regions of N- and C- concluding parts of S1 fold. Both NTD and C-domain has the potential to act as the receptor-binding domain (RBD), although the virus itself controls the preference. Both SARS-CoV and MERS-CoV, bind to their receptors with the help of C-domain[6, 7].
- Recently, Hoffmann et al. described that hACE2 (Human ACE2) is the entrance receptor of SARS-CoV-2, and also TMPRSS2, a serine protease, is essential for SARS-CoV-2 S activation.
Origin of COVID-19:
A group of researchers examined every important SARS-CoV-2 characteristics like the optimized RBD and polybasic splitting section, in relevant CoVs in nature. After analyzing the results, the researchers did not consider SARS-CoV-2 as a laboratory-based product. Hence, The novel SARS-CoV-2 which appeared in China last year is the outcome of natural evolution.
Protective measures against SARS-CoV-2:
According to WHO, to protect you and your family, everyone should follow the instructions given below ( Source: WHO)-
- Maintain social distancing
- Wash your hands frequently
- Avoid touching eyes, nose and mouth
- Practice respiratory hygiene
- If you have fever, cough and difficulty breathing, seek medical care early
- Stay informed and follow advice given by your healthcare provider
Recent investigation on finding out a possible cure for COVID-19:
Researchers all over the world are trying to develop a potential treatment for COVID-19. A possible treatment can be of various types, including potential drug discovery (both novel and existing), vaccine development, immunotherapy, etc. Here are the few recent updates ( up to 06th April 2020) on the COVID-19 research-
Drug Doscovery (both novel and existing):
- Scientists have discovered that Ivermectin is an inhibitor of SARS-CoV-2, and it has the potential to influence a ∼5000-fold decrease in viral RNA at 48 hours by applying once to Vero-hSLAM cells 2 hours post-infection with SARS-CoV-2 . Ivermectin is an FDA-approved anti-parasitic agent and has broad-spectrum antiviral activity in vitro. Therefore, it can be beneficial for humans and require additional investigation.
- Remdesivir and Chloroquine, two promising antiviral drugs, are profoundly useful in handling SARS-CoV-2 infection in vitro, recent research revealed (EC90 value of Remdesivir and Chloroquine against SARS-CoV-2 in Vero E6 cells was 1.76 μM and 6.90 μM respectively) 
- Recent investigation disclosed that Hydroxychloroquine medication is significantly linked with the reduction in the viral carriage in SARS-CoV-2 sufferers, and Azithromycin strengthens its effect . Another research also demonstrated that Hydroxychloroquine could inhibit SARS-CoV-2 in vitro more effectively than Chloroquine . Few safety concerns regarding the usage of Hydroxychloroquine and Chloroquine are risk of cardiac arrhythmias, retinal damage, especially with long term use, caution in patients with G6PD deficiency, diabetics, etc .
Apart from this, several drugs are on the process of clinical trials including-
|Condition or disease||Intervention/treatment||Phase||ClinicalTrials.gov Identifier|
|COVID-19||Drug: Deferoxamine||Phase 1 Phase 2||NCT04333550|
|COVID-19||Drug: Siltuximab Drug: Methylprednisolone||Phase 2||NCT04329650|
|COVID-19||Other: hyperimmune plasma||Not Applicable||NCT04321421|
|COVID-19||Drug: DAS181||Not Applicable||NCT04324489|
|COVID-19 Pneumonia||Drug: Best supportive Care (BSC) + IFX-1 Drug: Best supportive care only||Phase 2 Phase 3||NCT04333420|
|CODID-19||Drug: 1: Naproxen Drug: 2: Standard of care||Phase 3||NCT04325633|
|COVID-19 Pneumonia||Drug: Tocilizumab Injection||Phase 2||NCT04317092|
|COVID-19||Drug: Sarilumab Drug: Placebo||Phase 2 Phase 3||NCT04315298|
|COVID-19||Biological: NK cells,IL15-NK cells,NKG2D CAR-NK cells,ACE2 CAR-NK cells,NKG2D-ACE2 CAR-NK cells||Phase 1 Phase 2||NCT04324996|
These are the only few examples, and many more clinical trials are going on worldwide( Source: ClinicalTrials.gov).
Few clinical trials intend to develop a universal vaccine for SARS-CoV-2 are-
|Condition or disease||Intervention/treatment||Phase||ClinicalTrials.gov Identifier|
|Treat and Prevent Covid-19 Infection||Biological: Pathogen-specific aAPC||Phase 1||NCT04299724|
|Pathogen Infection Covid-19 Infection||Biological: Injection and infusion of LV-SMENP-DC vaccine and antigen-specific CTLs||Phase 1 Phase 2||NCT04276896|
|COVID-19||Drug: BCG Vaccine Drug: Placebo||Phase 3||NCT04328441|
|COVID-19||Biological: Recombinant Novel Coronavirus Vaccine (Adenovirus Type 5 Vector)||Phase 1||NCT04313127|
|Corona Virus Infection Immunisations||Biological: mRNA-1273||Phase 1||NCT04283461|
|Coronavirus||Biological: ChAdOx1 nCoV-19 Other: Saline Placebo||Phase 1 Phase 2||NCT04324606|
Research and Development in India
In India, scientists are also working hard to find out a cure for SARS-CoV-2 infection. In combating SARS-CoV-2, the contribution of Indian researchers are briefly described here-
- A low-cost paper-strip test, developed by the Institute of Genomics and Integrative Biology of Delhi, could identify COVID-19 within an hour . It could achieve India’s accelerated requirement for testing as each test would cost ₹500 (US$7.00).
- Pune-based molecular diagnostic company Mylab Discovery Solutions got the RT-PCR tests’ validation from the National Institute of Virology and the Indian Council of Medical Research (ICMR) . It became the first Indian company to get it. The test needs 2.5 hours and costs Rs 80,000 for a 100 test kit.
- India has published images of the coronavirus taken by the National Institute of Virology (NIV) investigators in Pune .
- Investigators have isolated 11 strains of the SARS-CoV-2 at the National Institute of Virology (NIV), Pune . Therefore India has become the fifth country to do it successfully.
- To combat SARS-CoV-2, India’s Council for Scientific and Industrial Research (CSIR) has made a collaboration with multiple companies, like TCS, BHEL, and Cipla.
- Defence Research and Development Organisation (DRDO) has taken part in combating the SARS-CoV-2 by making high-security face masks to full body assurance suits and multi-patient ventilators .
- To fight COVID-19, ISRO has acknowledged by resting launches and turning supplies to generate ventilators and hand sanitizer . Several IITs and IISc are also involved in making ventilators and PPEs, full-face shields, N95 masks, robotic units, drones, low-cost testing kits, handheld temperature measuring units, ICU beds, medical waste disposal for isolation wards, disinfection showers, mobile apps, etc [23, 24].
Please follow the official guideline carefully regarding COVID-19 and check the website regularly in case if there is any update. Stay home and stay safe.
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