Bharat Biotech which is facing criticism for not being able to scale up production of its COVID-19 vaccine Covaxin on May 28 said the manufacturing, testing, release and distribution of vaccines is a complex and multifactorial process with hundreds of steps, requiring a diverse pool of human resources.
The company said that there is a four-month lag time for Covaxin to translate from manufacturing to final vaccination.
"The timeline for manufacturing, testing and release for a batch of Covaxin is approximately 120 days, depending on the technology framework and regulatory guidelines to be met," the company said in a statement.
"Thus, production batches of Covaxin that were initiated during March this year will be ready for supply only during the month of June," the company said.
Bharat Biotech statement comes at a time when the company said it has the capacity to produce 10-12 million doses of vaccine, but there were reports in media that the actual supplies was far less than what was being announced. Bharat Biotech said it is ramping up capacities to 700 million doses by December.
Frequently Asked Questions
A vaccine works by mimicking a natural infection. A vaccine not only induces immune response to protect people from any future COVID-19 infection, but also helps quickly build herd immunity to put an end to the pandemic. Herd immunity occurs when a sufficient percentage of a population becomes immune to a disease, making the spread of disease from person to person unlikely. The good news is that SARS-CoV-2 virus has been fairly stable, which increases the viability of a vaccine.
There are broadly four types of vaccine — one, a vaccine based on the whole virus (this could be either inactivated, or an attenuated [weakened] virus vaccine); two, a non-replicating viral vector vaccine that uses a benign virus as vector that carries the antigen of SARS-CoV; three, nucleic-acid vaccines that have genetic material like DNA and RNA of antigens like spike protein given to a person, helping human cells decode genetic material and produce the vaccine; and four, protein subunit vaccine wherein the recombinant proteins of SARS-COV-2 along with an adjuvant (booster) is given as a vaccine.
Vaccine development is a long, complex process. Unlike drugs that are given to people with a diseased, vaccines are given to healthy people and also vulnerable sections such as children, pregnant women and the elderly. So rigorous tests are compulsory. History says that the fastest time it took to develop a vaccine is five years, but it usually takes double or sometimes triple that time.
The company further said that based on Central Drugs Standard Control Organisation(CDSCO) guidelines, all vaccines supplied in India are mandated by law to be submitted for testing and release to the Central Drugs Laboratory, Government of India.
All batches of vaccines supplied to state and central governments are based on the allocation framework received from the Government of India.
"The timeline for vaccine supplies to reach the depots of the State and Central Governments from Bharat Biotech’s facilities is around two days. The vaccines received at these depots have to be further distributed by the State Governments to various districts within their respective states. This requires an additional number of days," the company said.