Coronaviruses are a family of viruses mostly causing mild respiratory illness similar to common cold. They are reported to be present in animals as well as human beings. These viruses are also associated with outbreaks of serious disorders such as severe acute respiratory syndrome (SARS) caused by SARS-CoV in November 2002 and Middle East respiratory syndrome (MERS) caused by MERS-CoV in September 2012. The third and the most deadly outbreak of these virus family, COVID-19 is currently affecting millions of people worldwide.
What is COVID-19 and how does it spread?
COVID-19 is a highly infectious communicable viral disorder spread by the novel SARS-CoV-2 virus. The disease came into existence only after December 2019 when sudden outbreak of the novel coronavirus was reported in Wuhan, China. The disease was declared as global pandemic by World Health Organisation on March 11, 2020.
The most common symptoms of COVID-19 include:
- Sore throat
- Cough
- Fatigue
- Fever
- Headache
- Cold
These symptoms are mild and mostly last for a week. However, people with co-morbidities such as cardiovascular disease, diabetes, chronic respiratory disease, or cancer are more likely to develop severe conditions such as breathing difficulty or pneumonia.
SARS-CoV-2 virus spreads from one person to another via droplets released from sneezing, coughing, speaking or breathing of an infected person. The disease can also spread by touching surfaces containing viruses. In order to control the spread of the virus it is important for the infected person to follow respiratory etiquette, self-isolate and prevent any contact with others. It is also important for everyone to wear a mask, sanitise their hands and maintain a distance of 1 metre.
How has the Indian government and healthcare agencies dealt with the spread of this disease?
The first confirmed COVID-19 case of India was detected in January 2020, when a 20 year old female of Kerala was presented with symptoms of cold and cough after returning from Wuhan, China. Since then, a total of 36,582,129 confirmed cases of COVID-19 with 485,350 deaths have been reported to WHO from India, till 14 January 2022.
The Indian government imposed travel bans in February 2020 for Chinese and foreigners who had visited China in last two weeks. On March 2020, the National Disaster Management Authority (NDMA) urged the government to take preventive measures against the spread of COVID-19 followed which a complete nationwide lockdown for 21 days was imposed on 25 March 2020. The Indian government also imposed strict travel ban for all foreign nationals during this period.
Vaccine development and vaccination status in India
Coronaviruses are known as zoonotic viruses due to frequent transmission from animals to human in spillover event. Understanding the origin and genetic makeup of virus assist in development of therapeutics and vaccines. Bharat Biotech in collaboration with Indian Council of Medical Research (ICMR) – National Institute of Virology (NIV) developed Covaxin, India’s first vaccine for COVID-19.
The SARS-CoV-2 virus strain was isolated in NIV Pune and transferred to Bharat Biotech’s BSL-3 (Bio-Safety-level 3) high containment facility, where the indigenous and inactivated vaccine against COVID-19 was manufactured. In July 2020, the Drug Controller General of India (DCGI)- CDSCO approved the vaccine for Phase I & II human clinical trials after observing efficacy and safety results from preclinical trials. The vaccine will be administered in two doses with an interval of 28 days between the two doses.
Serum Institute of India (SII) signed agreement with Oxford-AstraZeneca for manufacturing their COVID-19 vaccine Covishield in India. Covishield is made from weakened version of common cold virus and was approved for restricted emergency use authorisation in India in January 2021 along with Covaxin. India began the world’s largest vaccination drive against COVID-19 on 16 January 2021, targeting a group of 300 million people beginning with frontline workers, people with serious health conditions and those aged 50 years or above. As of 16 January 2022, a total of 1,57,20,41,825 vaccine doses have been administered in India and 62% of adult population has been fully vaccinated.
What is the new omicron variant of COVID-19?
Similar to any other virus, the SARS-CoV-2 virus also undergoes mutations as a result of replication process. Some mutations may result in different lineage of virus giving rise to new variants of strain. Different variants such as alpha-α, beta-β, gamma-γ, delta-δ, omicron have been reported among which the delta and omicron variant has been classified as variant of concern.
The B.1.1.529 variant commonly known as omicron was first detected in South Africa in November 2021. The first confirmed case of Omicron were identified in December 2021 in United States as well as in India. The omicron variant has large number of mutations in the spike protein gene and is considered to be highly infective. Not much has been revealed about the lethality of this strain and studies are underway with respect to the effect of vaccination on omicron variant.
What is the status of booster dose in India?
Scientist from all over the world started evaluating effects of vaccination on omicron variant. Studies highlight the efficacy of COVID-19 vaccines in preventing severe illness, hospitalisations and death in COVID-19 patients. However, breakthrough infections may occur with omicron. On 24 December 2021, the Indian government announced booster doses for frontline workers, healthcare workers and those above 60 years who have received the second dose of vaccine 39 weeks earlier. Latest reports suggest that India’s Gennova Biopharmaceuticals has developed an omicron-specific mRNA vaccine which will soon be tested on human beings for efficacy and immunogenicity.
The fight against COVID-19 is far from over and it is crucial for everyone to follow COVID-guidelines and take necessary precautions to curb the spread of this deadly disease.
