The developer of the <a href="https://www.thenationalnews.com/world/europe/astrazeneca-s-covid-vaccine-should-you-be-worried-about-side-effects-1.1185534" target="_blank">Oxford-AstraZeneca Covid-19 vaccine </a>has played down fears of a new sub-variant of the Delta strain after reports that scientists are altering the drug because of the mutation. Prof Andrew Pollard, director of the Oxford Vaccine Programme, said the <a href="https://www.thenationalnews.com/coronavirus/2021/10/19/new-delta-variant-monitored-as-uk-covid-19-cases-rise/" target="_blank">AY.4.2</a> was only one of millions of variants that manifest themselves each day and insisted it has not taken hold in the UK. The UK government is keeping “a very close eye” on the sub-variant, which is estimated to account for almost one in 10 infections recorded since the start of October. The development comes as <a href="https://www.thenationalnews.com/world/uk-news/2021/10/20/pressure-for-plan-b-as-uk-covid-escalation-threatens-nhs/" target="_blank">ministers face intense pressure to introduce Plan B measures</a> due to rising infections. This would mean millions of people could once again find themselves working from home and having to wear face masks in indoor public places. Prof Pollard said the vaccines being administered under the UK’s drive were having a major effect on reducing severe infections and shortening the length of hospital stays. But he declined to confirm or deny reports claiming scientists were working on an altered version of the AstraZeneca shot to tackle AY.4.2 and dismissed the hype surrounding the strain. “This new sub-variant of Delta so far has not taken off,” he told the BBC Radio 4’s<i> Today</i> programme. “There are cases being reported and, of course, there are millions of new variants that will occur every day. Most of them fizzle out very quickly, perhaps not even straining once. “So, discovering new variants is, of course, important to monitor but it doesn’t indicate that that new variant is going to be the one to replace Delta. “And indeed, even if it does, Delta is incredibly good at transmitting in a vaccinated population and a new one may be a bit better but it’s unlikely to change the picture dramatically from where we are today.” <i>The Independent</i> quoted an Oxford-AstraZeneca source as saying a tweaked shot was in its “very early days” of development. The insider suggested it would not be complicated to modify the dose given the “plug and play” nature of the technology involved. They claimed that teams had started work on the change with the aim of “having something on the shelf ready to scale up – if it’s needed”. Prof Pollard said the situation faced by the country was “enormously different” compared to the circumstances last winter due to the high numbers already vaccinated. But Covid cases and deaths in the UK are increasing, fuelled by the<a href="https://www.thenationalnews.com/world/uk-news/2021/10/15/teen-vaccination-delay-triggers-uk-surge-in-covid-infections/" target="_blank"> slow uptake of vaccines among 12 to 15 age group</a>, some experts believe. Government data shows that 78.9 per cent of adults are fully vaccinated and 86 per cent have been given their first dose. Prof Pollard said the majority of Covid-positive patients in hospitals were frail, elderly or have pre-existing medical conditions, and were experiencing milder symptoms than patients in wards last year. Rather than requiring lengthy stays in intensive care, many “need some tuning up before they can be discharged”, he said. Official statistics show <a href="https://www.thenationalnews.com/world/uk-news/2021/10/19/uk-covid-daily-deaths-highest-since-march-amid-pressure-for-plan-b/" target="_blank">rising Covid infections and deaths</a> in Britain. On Tuesday there were 43,738 new infections recorded, the highest number in three months, continuing the trend of more than 40,000 new daily infections for the seventh consecutive day. There were 223 deaths added to the tally, the highest number of daily fatalities since March 9.