As coronavirus mutations undercut vaccine optimism, US scientists warn of a long fight

As coronavirus mutations undercut vaccine optimism, US scientists warn of a long fight

The world could be on the verge of having two more vaccines to fight the Covid-19 pandemic, but virus variants popping up worldwide are forcing companies that make the shots to develop boosters for a disease that could remain active for years.

Vaccines made by Moderna, the Pfizer-BioNTech partnership and Sinovac are already in use. Meanwhile, new studies show that two more – from Johnson & Johnson and Novavax – pack potent punches against early forms of the virus, potentially paving the way for quick authorisations in the US for J&J’s vaccine and in the UK for Novavax’s shot. That is the good news, offering the promise of ending a pandemic that’s killed more than 2 million people worldwide.

Now comes the bad news: Mutations that likely confer partial resistance to vaccines and antibody treatments are now prevalent in both South Africa and Brazil, and threatening to spread worldwide.

The J&J shot was found in a late-stage trial to be 72 per cent effective in the US, but that fell to 57 per cent in studies done in South Africa. Novavax’s shot, 89 per cent effective in the UK, was only 49 per cent effective in South Africa.