THIS is the new mantra for all nations of the world hit hard by the COVID-19 pandemic. There is no harm in doing everything possible to prevent the further spread of the virus in one’s country. Take the case of India which suffered the most from the devastating effect of the COVID-19 Delta variant. Recent reports bare that it (India) has already authorized the emergency use of their second homegrown COVID-19 vaccine, and with the additional approval for its use on children older than 12 years old.
The Department of Biotechnology of India has already announced its approval for the vaccine ZyCoV-D, manufactured by Indian pharmaceutical firm Zydus Cadila and touted as the “world’s first and India’s indigenously developed DNA-based vaccine for Covid-19.” Given that it is claimed to be the world’s first DNA-based COVID vaccine, several explanations have already been posted in social media and in the news about this.
In BBC news we learn the following: “DNA and RNA are building blocks of life. They are molecules that carry that genetic information which are passed on from parents to children. Like other vaccines, a DNA vaccine, once administered, teaches the body’s immune system to fight the real virus. ZyKoV-D uses plasmids or small rings of DNA, that contain genetic information, to deliver the jab between two layers of the skin. The plasmids carry information to the cells to make the “spike protein”, which the virus uses to latch on and enter human cells.
Most Covid-19 vaccines work by giving the body instructions to make a fragment of the spike protein so it can trigger a person’s immune system to produce antibodies and teach itself to fight off the virus. This is the world’s first human DNA vaccine against Covid-19. There are a number of DNA vaccines approved in the US, for example, for use in animals, including a vaccine for a disease in horses and a skin cancer vaccine for dogs. However, more than 160 different DNA vaccines are being tested in human clinical trials in the US. Most are devoted to treating existing cancers, and a third of the vaccines were for treating HIV. ZyCov-D is also India’s first needle-free Covid-19 jab. It is administered with a disposable needle-free injector, which uses a narrow stream of the fluid to penetrate the skin and deliver the jab to the proper tissue.
So this is the first of its kind DNA-based vaccine that will be used on humans and will be administered through a needle free injector. Other advantages of the ZyKoV-D vaccine is that, according to reports, it is relatively cheap, safe and stable and can be stored at a much higher temperature (-2 to 8degrees centigrade) and has good stability at 25 degrees centigrade for at least three months.
Are there any drawbacks or disadvantages? Well, according to Dr Jeremy Kamil, a virologist at Louisiana State University Health Sciences Center in Shreveport, “Plasmid DNA vaccines have been tried in the past. But we know it’s very difficult to get plasmid DNA into the nucleus of human cells, especially in adults.” On the other hand mRNA vaccines such as Moderna and Pfizer- which use messenger RNA to make the proteins – do not need to reach the nucleus of the cell to be effective and offer higher efficacy. Another drawback that was reported is that the ZyKoV-D requires three doses, instead of two for other vaccines currently in use.
Now aside from ZyKoV-D there is another homegrown vaccine made by India. This is the Covaxin developed by the Indian pharmaceutical company Bharat Biotech in collaboration with the Indian Council of Medical Research, a government funded biomedical research institute, and its subsidiary the National Institute of Virology. The Covaxin works by using a complete infective SARS-CoV-2 viral particle consisting of RNA surrounded by a protein shell, but modified so that it cannot replicate. This is similar to CoronaVac, the vaccine made by China, and is a two-dose regimen.
In other words, India which is the second-most populous country, the seventh-largest country by land area, and the most populous democracy in the world has not stopped trying to find ways and means to fight against the depredation of the COVID-19 virus. This is an example that other countries must follow if the world will have a chance of seeing the light at the end of the tunnel.
