A school pupil in Sussex has died after having suspected invasive Strep A illness, bringing the UK total to 16.
Data as of Thursday from the UK Health Security Agency (UKHSA) showed 13 children aged under 15 had died in England since September.
Two other deaths of children had been recorded in Belfast and Wales, taking the UK total to 15 at that point.
On Friday, the UKHSA said a Hove Park School pupil, whose age and gender were not given, had died having had suspected invasive Group A streptococcal infection (iGAS).
Specialists from the UKHSA are said to be working closely with Brighton and Hove City Council to support the school following the death.
Dr Rachael Hornigold, consultant in health protection at UKHSA South East, said: “We are extremely saddened to hear about the death of a young child and our thoughts are with their family, friends and the local community.
“Infection with Group A Streptococcus bacterium usually causes a sore throat, scarlet fever or skin rash, and is passed by physical contact or through droplets from sneezing or coughing.
“In very rare cases, the infection can become invasive and enter parts of the body where bacteria aren’t normally found, which can be serious.
“We will implement public health actions including advice to the city council and school community.”
Alistair Hill, director of public health at Brighton and Hove City Council, said: “We offer our heartfelt condolences to the family, friends and the whole school community who will all be deeply affected by the very tragic loss of this young child, and we are providing our support to them at this incredibly sad time. While we cannot comment on individual cases, we ask that the privacy of the family is respected.
“As a precaution, we have also been working closely with the school to raise awareness amongst parents and carers of the signs and symptoms of Group A Streptococcal infections, and what to do if a child develops these, including invasive Group A Streptococcal disease (iGAS).”
He said he wanted to stress that contracting iGAS disease from another person is “very rare” and that most people who come into contact with Group A Streptococcal infections “remain well and symptom-free – and therefore there is no reason for children to be kept home if well”.
Anyone concerned that their child seems seriously unwell is advised to contact NHS 111 or their GP.
Group A strep bacteria can cause many different infections, ranging from minor illnesses to deadly diseases.
Illnesses caused by Strep A include the skin infection impetigo, scarlet fever and strep throat.
While the vast majority of infections are relatively mild, sometimes the bacteria cause a life-threatening illness called invasive Group A Streptococcal disease.
The UKHSA has said there is no current evidence that a new strain is circulating and the rise in cases is most likely due to high amounts of circulating bacteria and increased social mixing.