Experts have revealed that two new strains of Covid-19 can reinfect people as early as 28 days after recovering from the virus.
The World Health Organisation (WHO) said yesterday that the virus is “running freely” as these strains increase infections worldwide.
These strains are not thought to be any more dangerous than previous variants, but they are more infectious.
Cases of coronavirus in the UK have continued to rise, and latest data states that around 2.7 million people tested positive in the week ending 29 June, up by 420,000 from the week before.
The ONS has said that the two new subvariants are driving some of these new infections.
What are the new Covid strains?
BA.4 and BA.5 are subvariants of the Omicron variant, which was at its peak in the UK over Christmas 2021.
According to the latest advice from the Australian Health Protection Committee, these subvariants are associated with “increased immune escape and we are likely to see rates of reinfection rise among those who have previously been infected with an earlier Covid-19 variant.”
They are not considered to be a more dangerous or deadly strain, but they are highly transmissible.
BA.4 was first detected in Limpopo, South Africa in January 2022, followed by BA.5 the following month, and both have spread to most South African provinces and worldwide.
Why are these variants different?
Omicron is much more likely to cause reinfection, as NHS data shows.
Data from the Office of National Statistics (ONS) found that reinfections were ten times higher in the period when Omicron was most common (20 December 2021 to 20 March 2022), compared to when the Delta variant was dominant (17 May to 19 December 2021).
As new variants develop and as time passes, our immunity to the virus gets smaller.
BA.4 and BA.5 share many of the same mutations as the original Omicron, but have even more in common with BA.2, another sub-strain that was also extremely transmissible.
Where are they spreading?
They are spreading quickly through Australia and on their way to becoming dominant and have already been confirmed dominant in some states including New South Wales and Victoria.
According to the Washington Post, Federal data indicates that the BA.4 and BA.5 subvariants make up about 80% of circulating coronavirus in the United States, where 67% of people have been fully vaccinated.
Europe health regulators have also recommended a second booster jab for high risk groups as a concerns about a new wave led by these variants rise.
The European Center for Disease Prevention and Control said in a statement: “A new COVID-19 wave is ramping up across the European Union.”
It also told governments to prepare for a “next expected wave in the autumn and winter seasons.”
What if I am vaccinated?
Unfortunately, vaccination does not protect you entirely from reinfection from these two variants, and neither does recent infections.
However, being fully vaccinated means that you are much less likely to be hospitalised or get seriously ill from coronavirus.
Can I get another booster after 28 days to avoid reinfection?
No, it is still recommended that an interval of three months is left between an infection and a booster jab.
However, staying up to date with jabs recommended by the NHS is worth doing as it will keep your risk of hospitalisations low.
