New Omicron variant: symptoms of BA.4 and BA.5 strains - and where is Covid spreading in the UK?

Two new Omicron subvariants are causing a rise in Covid cases, sparking concerns the UK could be faced with a new wave of infections.

Parts of the country are showing early signs of an increase, according to new figures from the Office for National Statistics (ONS).

Data up to 2 June shows that three counties in England and Northern Ireland are starting to see a spike in infections, with the BA.4 and BA.4 Omicron variants thought to be to blame.

What are the BA.4 and BA.5 strains?

The BA.4 and BA.5 Omicron strains are newer variants that were recently classified by the UK Health Security Agency as “variants of concern”.

Analysis found that both variants were likely to have a “growth advantage” over BA.2, which is currently still the dominant Covid strain in the UK.

Initial findings suggest that BA.4 and BA.5 have a degree of “immunity escape”, meaning the immune system can no longer recognise or fight a virus.

This is likely to contribute to their growth advantage over BA.4, according to the UK Health Security Agency (UKHSA).

Dr Meera Chand, UKHSA director of clinical and emerging infections, said: “The reclassification of these variants as variants of concern reflects emerging evidence on the growth of BA.4 and BA.5 internationally and in the UK.

“Whilst the impact of these variants is uncertain, the variant classification system aims to identify potential risk as early as possible.

“UKHSA is undertaking further detailed studies. Data and analysis will be released in due course through our regular surveillance reporting.”

Where are BA.4 and BA.5 spreading?

BA.4 and BA.5 emerged in South Africa and were added to the World Health Organisation’s (WHO) monitoring list in March. They have also been designated as variants of concern in Europe.

The variants were detected in South Africa at the beginning of the year and now appear to be spreading more quickly than other strains.

The variants have been reported in most European countries, including France, Austria, Denmark, Germany, Italy, the Netherlands and Belgium, and they have also been found in the US, Hong Kong, Canada and Australia.

They look set to overtake other Covid variants as the dominant strain, with BA.5 now already dominant in Portugal.

The US has also reported rising case numbers caused by the two variants, with the UK also showing early signs of a possible rise.

New ONS data shows all four UK nations have seen a slight rise in the prevalence of Covid, although the trend is described as “uncertain” in Scotland and Wales.

Among the regions of England, infection levels are estimated to have increased in the North West, London and the South East, with early signs of an increase in eastern England. Levels have fallen in the South West and the West Midlands while the trend in all other regions was uncertain.

A total of 797,500 people in England were estimated to have tested positive for Covid last week – the equivalent of about one in 70. This is up week on week from 784,100, which was also about one in 70.

Northern Ireland has seen infections rise for the second week in a row to 27,700 people, or one in 65, up from 24,300 people, or one in 75.

In Scotland, 124,100 people are estimated to have had the virus last week, or one in 40, up from 105,900, or one in 50.

Wales has seen infections increase very slightly to an estimated 40,500 people, or one in 75, up from 39,600, also one in 75.

Should we be worried?

The BA.4 and BA.5 variants are not thought to be any more severe than other Covid strains, although they appear to be spreading more easily.

This is thought to be due to waning immunity and because of the many mutations the virus has undergone.

It appears that BA.4 and BA.5 are able to infect people even if they have recently been infected with other strains of Omicron, but there is currently no data to determine the impact of the variants on hospital admissions or deaths in the UK.

What symptoms should I look for?

The NHS extended its list of Covid symptoms earlier this year to reflect the wider array of signs that could indicate infection. People are advised to look for the following:

• a high temperature or shivering (chills) – a high temperature means you feel hot to touch on your chest or back (you do not need to measure your temperature)
• a new, continuous cough – this means coughing a lot for more than an hour, or 3 or more coughing episodes in 24 hours
• a loss or change to your sense of smell or taste
• shortness of breath
• feeling tired or exhausted
• an aching body
• a headache
• a sore throat
• a blocked or runny nose
• loss of appetite
• diarrhoea
• feeling sick or being sick

The legal requirement to self-isolate after a positive Covid test ended across the UK earlier this year, with the governments instead asking people to take “personal responsibility”.