The Isle of Wight is the UK’s Strep A epicentre, data suggests, with the island suffering with a rate of scarlet fever higher than anywhere else in the country.
Scarlet fever is one manifestation of Strep A and is a good barometer for general circulation of the bacteria.
Strep A also causes impetigo, strep throat or, in the most extreme and rare cases, invasive Group A Strep (iGAS) which has killed at least nine children in the last few weeks.
The rate had increased by a similar amount for the more dangerous iGAS, surging from 0.5 per 100,000 one to four-year-olds before the pandemic to 2.3 per 100,000.
Health authorities have admitted the spike in Strep A cases is a result of lockdowns over the last few winters which curbed social mixing.
As a result, there is now a much larger pool of children with no immunity to the infection which means a child is far more likely to encounter the bacterium now than in normal years.
But while the four-fold spike average increase is alarming, it is much worse in some parts of the country.
On the Isle of Wight, for example, there have been 67 cases of scarlet fever in the last four weeks, equivalent to a rate of 47 cases per 100,000 people.
The Isle of Wight saw just 2.6 cases per 100,000 people before Covid over the same time period, data show, with this season’s figures marking an 18.1-fold increase.
Allerdale in Cumbria and Three Rivers in Hertfordshire are second and third worst, respectively, with scarlet fever rates of 40.89 and 25.54 per 100,000 people.
These are up 17 and 18.2-fold, respectively, when compared to the average for the three winters before Covid struck, spanning from late 2017 to early 2020.
Great Yarmouth is the area with the biggest increase in scarlet fever rates, jumping from 0.3 per 100,000 pre-Covid to 11.09 in this past month, a 37-fold increase.
Harborough (23.6-fold), Rugby (22.6), Boston (22.6), Uttlesford (18.9) and Three Rivers (18.2) are the only other areas with steeper rises than the Isle of Wight.
While the Isle of Wight currently has the worst rate in the country for cases per population, the local authority with the biggest number of raw cases is Leeds, with 97 last week.
Leicestershire (76) and Hampshire (68) are the only other two to top the Isle of Wight in terms of raw numbers.
But the Isle of Wight is home to just 142,000 people, almost ten times fewer than in Hampshire (1.38 million).
Leicestershire and Leeds are both home to more than 700,000 people, also dwarfing the Isle of Wight.
Leeds has the 33rd worst scarlet fever rate in the country at 12.1 per 100,000, with Leicestershire 47th (10.7) and Hampshire178th (4.9).
Figures from the UK Health Security Agency (UKHSA) show that for the week ending December 4 there were 1,131 cases of scarlet fever, up more than 250 on the week before.
There have now been 23,034 cases of scarlet fever so far in England and Wales in 2022, almost ten times the 2,323 figure at this time last year.
Authorities were also notified of ten cases of iGAS last week, in Bromley, Hillingdon, Hounslow, Lewes, Newport, Plymouth, Rochdale, South Holland, Stafford and Wiltshire. It is unknown what age these cases are and if they are children.
The Isle of Wight council has been approached for comment.