New data suggests that the number of people testing positive for COVID-19 across the UK is rising again. For the week ending June 2, the Office for National Statistics (ONS) said there were “early signs of a possible increase in the percentage of people testing positive for Coronavirus”, with figures suggesting that in England and Northern Ireland, the positivity rate was one in every 70 people and one in every 65 people, respectively.

Infection rates rose again across the UK following the Jubilee weekend when an estimated 1.4 million people, or one in 45, had the virus – a rise of 43 per cent.

Whether this is the start of another wave is uncertain. The Jubilee weekend would have provided a good opportunity for the virus to spread as people gathered to celebrate over the long bank holiday weekend, so it may cause only a temporary rise. However, health officials say the rise in COVID-19 is being driven by new fast-spreading sub-variants of Omicron – BA.4 and BA.5.

In addition, a study released by Imperial College London, reported that being infected with Omicron does not provide much immune protection from being reinfected, and that people can catch these new subvariants even if they have had COVID before. However, these sub-variants of Omicron (BA.4 and BA.5) are not thought to cause more severe disease than other types of COVID-19, and vaccines are still offering protection and saving lives. There is also, at present, no increase in admissions to intensive care units.

In the week ending June 9, the COVID rates were:

One in 50 in England (up from 1 in 70 the week before)
One in 45 in Wales (up from 1 in 75)
One in 45 in Northern Ireland (up from one in 65)
One in 30 in Scotland (up from 1 in 40)

All COVID restrictions have been lifted in the UK, and testing is scaled-down. Free lateral flow tests are no longer available. So, as we enter summer, it seems the key message is to remember that COVID is still with us. BA.4 and BA.5 were first identified in South Africa at the start of the year. Cases are growing across Europe and they may soon become the dominant strains in Europe and the US.

Immunity from COVID-19 through infections and vaccination means most people have some protection from the virus, but the new variants still seem to spread quickly. This may be due to various factors such as immunity waning after vaccination or infection, the virus has mutated and variations in an individual’s immunity. Due to genetic mutations, BA.4 and BA.5 seem to have antibody evasive properties.

People’s immunity to COVID will depend on which strain they were infected with when they had COVID and their vaccination history. This was highlighted in the Imperial College study, which was carried out on 700 London health workers from March 2020 onwards. The results showed that even though participants had all had three vaccine doses, their Omicron re-infection rates differed. This is related to a concept called ‘immune printing’.

If you were infected with an earlier variant of COVID-19, e.g., the Beta variant then your body will have produced antibodies to specific markers or antigens of this virus strain. It may then be that if you are infected with a later variant that has mutated, your body uses the same immune response it used in your first encounter with the virus, but it might need to produce a different immune response to produce different antibodies to effectively get rid of the new variant of the virus – as it has mutated and changed.

Scientists say they are beginning to see evidence that this is the case with these new Omicron sub-variants. As these sub-variants can re-infect people who have had

COVID before, there is potential for them to spread easily.
The key question is, will this be the start of the 5th wave of COVID? Currently, the sub-variant BA.2 makes up most of the infections in the UK, while BA.3 is primarily found in South Africa. Sub-variants BA.4 and BA.5 emerged in May in the UK and could be the start of another wave

It is difficult to predict at this point how significant the rise in cases will become as they could plateau, and during the summer months when we spend more time outdoors and have increased ventilation in our homes, numbers may be kept down. However, many experts expect COVID cases to rise again in the autumn as we spend more time indoors, and schools and colleges re-open.

Rachel Kayani