Covid-19 Vaccine Matters: J&J jab could be a breakthrough for India's supply crunch

All you need to know on the coronavirus and vaccination front right now

As daily Covid-19 cases in India remain above 40,000, the government is targeting more vaccinations by increasing monthly vaccine productions. India recorded 44,643 new coronavirus infections on Friday taking the total tally of Covid-19 cases to 3,18,56,757, while the active cases registered an increase for the third consecutive day.

The monthly production capacity of Covishield is projected to be increased to more than 12 crore doses and of Covaxin to around 5.8 crore doses by December, the government told Rajya Sabha on Tuesday, citing information from the Covid-19 vaccine manufacturers. Bharat Biotech said that the Covaxin doses manufactured at its Malur, Karnataka, and Ankleshwar, Gujarat plants would be available for supply in September. The Hyderabad-based company commenced the production at these two sites in early June.

What could come as a relief to the government, facing flak over supply crunch and setting an overambitious target, could be an approval for Johnson & Johnson's single-dose Covid vaccine.

Johnson & Johnson on Friday said it has applied for Emergency Use Authorization (EUA) of its single-dose Covid-19 vaccine in India. Earlier on Monday, the company had said that it remained committed to bringing its single-dose Covid-19 vaccine to India and looks forward to ongoing discussions with the Indian government. This is an important milestone that paves the way for bringing the company's single-dose Covid-19 vaccine to the people of India, and the rest of the world, through a collaboration with Biological E Limited, the company said in a statement.

As the clamour for booster shots or a third dose grows, CanSino Biologics found that antibody levels in people inoculated with its single-dose Covid-19 vaccine (CanSinoBIO) fell by some 30 per cent after six months. A booster shot could offer a significant lift, a senior executive said late on Thursday.

The decline in antibodies does not necessarily mean the shots will lose their protection, though how fast they wane could still serve as an important indicator of the immune response, Zhu Tao, chief scientific officer at China's CanSinoBIO, said in an online presentation. A third booster shot of CanSinoBIO's vaccine three to six months after the second shot of an inactivated vaccine generated significantly higher antibody levels, versus using an inactivated vaccine as a third-dose booster, Zhu said. He cited data from about 200 participants in a clinical trial.

Moderna said on Thursday its Covid-19 shot was about 93 per cent effective four to six months after the second dose, showing hardly any change from the 94 per cent efficacy reported in its original clinical trial. A durable vaccine could mean recipients may be able to wait longer between shots if they do eventually need a booster or may even not need additional doses to prevent Covid-19.

However, the World Health Organization called for a moratorium on coronavirus vaccine booster shots until the end of September, so that vaccine supplies can be focused on helping all countries vaccinate at least 10 per cent of their populations.

With the debate over booster shots heating up, the call highlighted a moral and scientific case long pressed by humanitarian groups: With the staggering gaps in vaccination rates around the world and cases surging as the Delta variant spreads, vaccine doses should be given first to vulnerable people in poorer nations. Fully-vaccinated people are protected against the worst outcomes of Covid-19 caused by the Delta variant.

The highly-transmissible Delta variant of Covid-19 has now been reported in 135 countries, according to the World Health Organization, which said the cumulative number of coronavirus cases reported globally could exceed 200 million by next week.

As both the numbers of vaccinations and coronavirus cases rise, people are becoming more and more worried about 'breakthrough infections'.

A “breakthrough” simply means that a vaccinated person has tested positive for the disease-causing agent, not that they will become ill or transmit the infection to someone else. Most vaccinated people who are infected do not have symptoms, and those that do, tend to have mild illness. Even with the Delta variant of SARS-CoV-2, the vaccines show good protection against symptomatic disease and death.

Covid vaccines are expected to reduce transmission among those with an asymptomatic breakthrough infection, says Nick Grassly, a professor in the department of infectious disease epidemiology at Imperial College London. “So you already have the fact that you’re immunised and less likely to become infected, and even if you are infected, your risk of transmitting the virus is reduced,” he adds. Fully-vaccinated people have an around 50 to 60 per cent reduced risk of infection from the Delta coronavirus variant, including those who are asymptomatic, a large English coronavirus prevalence study found on Wednesday.

While states like Karnataka, have reimposed some curbs to check the rate of infections, the National Technical Advisory Group on Immunisation (NTAGI) has recommended that states relax the RT-PCR requirement guidelines for those who are fully-vaccinated.

Even the Bombay High Court on Thursday asked the Maharashtra government to think about identifying and separating those who have taken both doses of Covid-19 vaccine from the rest, and provide a "common card" to the fully-inoculated people to allow them unrestricted travel and work.

The rise in fresh Covid cases and the effective reproduction number – indication of how fast an infection spreads -- in many states is worrying but experts say that it is too early to declare the beginning of a new wave. In fact, it could be that the second wave is not over, said several scientists who have been closely monitoring India’s Covid graph and have noted the surge in a few pockets.