Health experts have issued a stark warning over the rapid reinfection rate of the new Omicron BA.5 variant.
A combination of vaccinations, antibody treatments and natural immunity from from previous exposure to Covid-19 had been keeping infections in the UK in check.
However, experts have warned that new variants can reinfect even those with some form of antibody immunity in a matter of weeks.
Western Australia's chief health officer Andrew Robertson told news.com.au : “They (new variants) seem to be able to evade the protection from either having had a previous infection with BA2 or having had a vaccine.
“What we are seeing is an increasing number of people who have been infected with BA2 and then becoming infected (again) after four weeks,” he said.
“So maybe six to eight weeks (later) they are developing a second infection and that’s almost certainly either BA4 or BA5.”
The latest Government figures show that coronavirus cases in England had risen by 26.5% in a week to 139,272 infections, prompting the UK Health Security Agency (UKHSA) to remind people to ensure they have had any vaccines that they are eligible for and to follow Covid-safe practices such as regular hand washing.
The latest Covid information on gov.uk says that BA.4 and BA.5 are quickly becoming the dominant variants, stating: “UKHSA’s latest analysis suggests that Omicron BA.5 is growing 35.1% faster than Omicron BA.2, while Omicron BA.4 is growing approximately 19.1% faster.
“This suggests that BA.5 is likely to become the dominant Covid-19 variant in the UK.
“The increasing prevalence of Omicron BA.4 and BA.5 is likely to be a factor in the recent increase in cases seen in the UK and elsewhere, though there is currently no evidence that Omicron BA.4 and BA.5 cause more severe illness than previous variants.”
Dr David Dowdy, an epidemiologist at John Hopkins Bloomberg School of Public Health told Insider that BA.4 and BA.5 reinfections were thought to be less severe than earlier Covid outbreaks.
He said that as the virus evolves to develop resistance to antibodies, the body's immune system becomes better at dealing with it.
Dowdy said: “While the immune system still churns out antibodies to neutralise an infection, that protection tapers off over time.
“It's not an on-off switch but if someone is exposed to a tricky subvariant as their protection is waning, the virus may find an opening.
"Anything that can get around that immune response just a little bit faster has an advantage when a lot of the population is immune”.
