Prof. M Zahidul Haque :
Bangladesh had been using the Astra-Zeneca jab made by Serum Institute of India. But unfortunately, the Serum Institute of India has expressed their inability to supply the Astra-Zeneca vaccine to Bangladesh because of its high demand within India following tremendous rise in Covid-19 patients in their own country. So, Bangladesh started looking for alternative sources to make corona vaccine available for its citizens. The government has already given approval to Russia’s Sputnik V vaccine for emergency use in the country. The Government is also making communications with different vaccine producing countries including the United States for obtaining corona vaccines. It has plan to manufacturing Sinovac and Sputnik V vaccines locally under technical support of China and Russia respectively.
Corona virus’s unending journey has increased its speed of transmission through mutation of its original strain. As a result, highly-transmissible SARS-CoV-2 corona virus variants like African variant, UK Variant and most recently Indian double and triple variants evolved. Mutation of SARS-CoV-2 coronavirus has emerged as a major barrier on the way to keeping efficacy of the vaccine. It seems that a series of vaccines required to be produced for each variant.
There are of course some side effects of Covid-19 vaccines (allergy, blood clotting, etc.) but the volume of benefits is much greater than the side-effects. However, the scientists are working day and night to make vaccines more efficacious and safe.
Meanwhile some protective measures need to be maintained to get rid of the SARS-CoV-2 corona virus infection and to reducing the virus’s transmission:
–maintaining hand hygiene, social distancing, wearing mask; double masks while attending a corona patient and visiting widely affected areas
–the public toilets’ flash aerosols may act as a potential vector for spreading corona virus: attention should be given on keeping public toilets clean and disinfected
–remaining always prepared to encounter Covid-19 emergencies to save patients’ lives, for instance, steady oxygen supply. It may be mentioned here that a huge number of severely ill patients had to die in our neighboring country India due to non-availability of oxygen.
SINCE its emergence in China’s Wuhan city, Corona virus (SARS-CoV-2), the Covid-19 causing virus has been rolling on invading countries making people infected and sick. Severe Acute Respiratory Syndrome (SARS) Corona viruses are a large family of viruses that live mainly in animals like bat, pig, etc. But somehow it entered into humans. Some strains of corona virus are capable of causing severe illness among the human beings. Earlier in 2003 and 2012, strains of corona virus caused Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS) in China and Saudi Arabia respectively. The present SARS-CoV-2 Covid-19 emerged as a novel member of the corona virus family creating a world-wide pandemic making hundreds of thousands of people sick and killing millions other.
According to the available genome sequence data, the SARS-CoV-2 has evolved through evolution, not as suspected that the novel corona virus was made in the laboratory by genetic manipulation. In fact, Covid-19 corona virus has similarities to Influenza virus-both cause respiratory diseases. But unfortunately, influenza vaccine does not work on Covid-19 patients. Covid-19 has more mortality rate in comparison to influenza. Some SARS-CoV-2 variants cause even more severe respiratory distress that requires emergency high-flow oxygen therapy as the patient loses the strength to breath normally.
Viruses are often referred to as non-living because like parasite they depend on cells of other organisms for their survival and replications. Viruses contain RNA or DNA as their genetic material. In fact, Deoxyribonucleic acid (DNA) and Ribonucleic acid (RNA) is of great importance to human as well as all living organisms including viruses. DNA and RNA stores genetic information and play a pivotal role to growth, reproduction and health. Even the plants also use DNA and RNA for carrying forward their genetic instructions for ensuring growth and development. The main difference between plants and humans is-plants have in-built immune system to fight against pathogens. They defend themselves against viruses by RNA silencing (innate immune resistance to virus). Humans have also sets of strong immune system; one is inherited and the other is adaptive immune system (antibodies).
In order to control spread of corona virus, the researchers have developed some vaccines. All COVID-19 vaccines work to boost human immunity to the virus. At present 4 types of vaccines are in use, viz. Whole Virus, Protein Subunit, Viral Vector and Nucleic Acid (RNA and DNA). Produced on the basis of the above mentioned virus types, the following vaccine candidates got approval and widely in use: BioNTech-Pfizer (mRNA vaccine), Moderna (mRNA vaccine), Oxford Astra-Zeneca (adenovirus vaccine), Johnson & Johnson (adenovirus vaccine), Sinovac (inactivated corona virus) and Sputnik V (adenoviruses).
Although yet to reach the entire population of the world, production of vaccine is increasing rapidly; emphasis on the equitable distribution of Covid-19 vaccines to all the countries have to be ensured. In order to attain ‘herd immunity’, majority of the people in every country have to be vaccinated. Meanwhile the WHO initiated Covid-19 VACCINES GLOBAL ACCESS (COVAX) in collaboration with Gavi, the Vaccine Alliance is working towards ensuring equitable access to vaccine of all the people of the world. The World must work together as a single family to put a brake to the rolling of SARS-CoV-2 corona virus with a view to bringing smile back to our dear ‘Earth’ making it free from the pandemic.
(The writer is a professor, Department of Agricultural Extension & Information System, Sher-e-Bangla Agricultural
University)
