New Delhi | Jagran News Desk: With an aim to start the COVID-19 vaccination drive for children in the country, the Centre has placed a purchase order of one crore doses with Zydus Cadila for its anti-coronavirus vaccine ZyCoV-D, reported news agency PTI quoting government sources. The sources said that indigenously developed three-dose ZyCoV-D, which is touted as the world's DNA-based COVID-19 vaccine, will be given to adults initially under the Centre's nationwide inoculation drive "because of limited production capacity".

"The Centre has already placed a purchase order with Zydus Cadila for supply of one crore doses of ZyCoV-D, each costing around Rs 358 excluding taxes, at the earliest. This price includes the cost of a disposable painless jet applicator which has to be used for administering each dose," PTI quoted the sources as saying.

What is a needle-free vaccine and how it will be administered?

Needle-free injection technology (NFIT) uses drug delivery systems through the skin like shock waves, electrophoresis or pressure by gas to propel the drug through the skin. The device used for this process is generally reusable and requires little training to administer the drug. For ZyCoV-D, a device named 'Tropis' will be used. It will deliver the vaccine 'intradermally', propelling it through the skin with high pressure. For this, only three components - filling adapter, injector and needle-free syringe - are required.

Following are the step how ZyCoV-D will be administered:

1. First of all, healthcare workers would need to prepare the injector.

2. The second step includes filling the syringe.

3. Following this, the healthcare workers would need to load the injector.

4. At last, the vaccine would be administered through the Deltoid region.

Advantages of needle-free vaccine:

It is claimed that needle-free vaccines can be easily administered with more accuracy and require little training. Needle-free vaccines will also help healthcare workers avoid 'needlestick injuries'.

Why this is favoured for kids?

The needle-free vaccine is favoured for kids as it "will reduce the pain of vaccination", say experts. "When I became a mother myself and started taking my own children for vaccinations and hospital visits, I realized that there's a ton of great science out there about how to make needles and other types of painful procedures easier for kids," Forbes quoted Dr Christine Chambers, a professor in Dalhousie University in Halifax, as saying.

What is a DNA-based vaccine?

ZyCoV-D is the world's first DNA-based anti-COVID-19 vaccine. It works on the DNA based formula under which the vaccine will produce spike protein of the SARS-CoV-2 virus once it is injected and help the body generate an immune response against the infection.

As per World Health Organisation (WHO), DNA-based vaccines involve "the direct introduction into appropriate tissues of a plasmid containing the DNA sequence encoding the antigen(s) against which an immune response is sought, and relies on the in situ production of the target antigen".

"This approach offers a number of potential advantages over traditional approaches, including the stimulation of both B- and T-cell responses, improved vaccine stability, the absence of any infectious agent and the relative ease of large-scale manufacture," the WHO said.

Why ZyCoV-D will be administered to adults first?

The three doses of ZyCoV-D, which will be administered 28 days apart, was given the emergency use authorisation Drugs Controller General of India (DCGI) on August 20 this year. It will be administered to adults first in India under the Centre's nationwide vaccination drive.

"The vaccine in all probability will be given to adults initially because of limited production capacity," PTI quoted government sources as saying.

Posted By: Aalok Sensharma