New Delhi, Almost a year after reporting the first case of deadly coronavirus, which has claimed over 1.5 lakh lives in India till now, the country is set to witness a historic moment on Saturday with the commencement of the eagerly-awaited vaccination drive against the dreaded disease.

Prime Minister Narendra Modi will virtually launch the world's largest vaccination programme at 10:30 a.m. on Saturday and almost three lakh beneficiaries, belonging to the priority groups, will be administered the silver bullet at over 3,006 vaccination sites across the country. Around 100 beneficiaries will be vaccinated at each session site.

The vaccine will be first offered to the healthcare workers, frontline workers and those above 50 years of age, followed by the below 50 population with comorbidities, and finally to the remaining population based on disease epidemiology and vaccine availability.

The vaccination drive has been planned in a phased manner, identifying the priority groups. Healthcare workers, both in government and private sectors, including Integrated Child Development Services (ICDS) workers, will receive the vaccine in the first phase.

Two vaccines -- Oxford Covid vaccine Covishield manufactured by the Serum Institute of India, and indigenously developed Covaxin by the Bharat Biotech -- will be administered to priority groups. Till now, the Central government has procured 1.1 crore Covishield and 55 lakh Covaxin vaccines at a cost of Rs 200 and Rs 206 per dose, respectively.

Earlier on Friday, Union Health Minister Harsh Vardhan said that India's exercise to vaccinate its population against Covid-19 will be the largest immunisation drive in the world. The minister reiterated that both the indigenously manufactured vaccines have proven to be safe.

The Covid-19 Vaccine Intelligence Network (Co-WIN) system, a digital platform, will be used to track the enlisted beneficiaries on a real-time basis. Prime Minister Modi will launch the app on Saturday.

The platform enables national and state administrators to view and sort the data of the beneficiaries as per their gender, age and comorbidity. They can also view the metadata of vaccination and the Adverse Event Following Immunisation (AEFI) reported from the constituent districts.

At the vaccination site, only pre-registered beneficiaries will be vaccinated as per prioritisation, and there will be no provision for on-the-spot registrations. A dedicated 24x7 hotline - 1075 - has also been set up to address questions related to the vaccine rollout and the Co-WIN app.

The entire vaccination process will be broadly similar to the election process. Each vaccination team will consist of five members, including security personnel, nurses, paramedics and a doctor. Three will be a waiting area, an inoculation room and a post-vaccination observation area. There will also be a reception desk for registration and verification of the beneficiaries.

Explaining the process of the vaccination drive, Ajeet Jain, the nodal officer of Delhi's Rajiv Gandhi Super Specialty Hospital, said, "The whole process from registration of beneficiaries to observation post-vaccination will take 45 minutes. At the entry point, vaccination officer-I will verify all the documents of the beneficiaries. On being cleared, they will come to the waiting area and wait for their turn."

"From the waiting room, they will enter the vaccination room. The rooms are equipped with stretchers to shift a patient to the ICU in case of any untoward incident post-vaccination. ECG machine, monitor and oxygen mask will be available on the spot. After receiving the vaccine, the beneficiaries will be kept under observation for 30 minutes," Jain added.

Notably, only those above 18 years will be vaccinated. Pregnant women or who are not sure of their pregnancy and lactating mothers should not take the vaccine. Those with a history of bleeding or coagulation disorder will be administered the vaccine with utmost caution.

Vaccination will have to be deferred for four to eight weeks after recovery of patients with active Covid symptoms, or those who have been given plasma therapy, and those who are unwell or have been hospitalised for any other reason.

The second dose of the Covid vaccine will be administered after an interval of fourteen days. Also, interchanging Covid-19 vaccines is not allowed.

The mild adverse impacts of the Covishield vaccine could be headache, fatigue, pain in muscle, injection site tenderness, weakness, pyrexia, chills, arthralgia and nausea.