At least 19 children have now died across the UK from invasive Strep A disease, new figures show.
It comes as the government acknowledged supply issues of some of the drugs used to treat infections caused by the bacteria.
Data from the UK Health Security Agency (UKHSA) shows 16 children under the age of 18 have died in England since September.
Three other deaths of children have been recorded in Belfast and Wales, taking the UK total to 19.
It is understood that health officials do not believe the number of scarlet fever infections has yet peaked, suggesting more deaths are likely.
Meanwhile the Government has introduced serious shortage protocols (SSPs) for three penicillin medicines.
The move means pharmacists can legally supply alternative forms of the medicine if they do not have the specific formulation stated on the prescription, such as an oral solution.
The SSPs, which cover the entire UK, are intended to lessen the need for patients to return to their GP for a different prescription when they cannot get hold of a medicine. Penicillin comes as liquid, sugar-free liquid and pills.
But pharmacists said they were “baffled” as to why it had taken so long for the Government to introduce the protocols.
The majority of those who become critically ill with iGAS do so because of sepsis— Ron Daniels, UK Sepsis Trust
Leyla Hannbeck, chief executive of the Association of Independent Multiple Pharmacies, told BBC Radio 4’s PM programme: “This is a step in the right direction, and it will make the journey easier for patients and make it easier for pharmacists.
“However, we’ve raised this concern about the shortage of antibiotics for many days now and we’re baffled by the fact that this has taken so long for things to move forward and for things to be planned accordingly.
“What happens now is the pharmacist will be able to prescribe an alternative antibiotic, according to the protocol.”
She added: “The supply of antibiotics generally at the moment is very patchy and it’s very difficult to get hold of them – as soon as something becomes available it just flies off the shelves because of the high demand.
“But this is certainly a step into in the right direction. However, this should have happened much earlier.”
Symptoms to look out for include fever, sore throat, swollen glands, difficulty swallowing, and headache. Scarlet fever causes a sandpapery rash on the body and a swollen tongue— Dr Colin Brown, UKHSA
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 (iGAS) 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.
It said that, since September, there have been 7,750 notifications of scarlet fever, more than three times the number in the last high season in 2017/18.
There have been 111 iGAS cases in children aged one to four and 74 cases in children aged five to nine.
Since September, 74 people of all ages have died in England.
Dr Colin Brown, deputy director of the UKHSA, said: “Scarlet fever and ‘strep throat’ will make children feel unwell, but can be easily treated with antibiotics.
“Symptoms to look out for include fever, sore throat, swollen glands, difficulty swallowing, and headache.
“Scarlet fever causes a sandpapery rash on the body and a swollen tongue.
Public Health Wales has confirmed it is investigating the deaths of two children as possible iGAS cases— Public Health Wales
“NHS services are under huge pressure this winter, but please visit nhs.uk, contact 111 online or your GP surgery if your child has symptoms of scarlet fever or ‘strep throat’ so they can be assessed for treatment.”
He said parents should also look out for signs their child is getting worse after a bout of scarlet fever, a sore throat or respiratory infection.
In Wales, a spokesman for Public Health Wales said: “Public Health Wales has confirmed it is investigating the deaths of two children as possible iGAS cases.
“Due to the risk of identification, Public Health Wales will not confirm numbers of deaths lower than five.”
However the families of seven-year-old Hanna Roap, from Penarth, South Wales, and a child from Powys who has not been named, have confirmed the cause of death of both children was iGAS.
Ron Daniels, chief executive of UK Sepsis Trust, said: “The majority of those who become critically ill with iGAS do so because of sepsis.
The increased demand for the antibiotics prescribed to treat Strep A has meant some pharmacists have been unable to supply the medicine shown on the prescription— Will Quince, health minister
“This is why co-ordinated education and public messaging around both Group A Strep and sepsis symptoms is critical to ensuring people can be diagnosed and treated quickly and to prevent further lives lost.”
Commenting on the introduction of the shortage protocol, health minister Will Quince said: “The increased demand for the antibiotics prescribed to treat Strep A has meant some pharmacists have been unable to supply the medicine shown on the prescription.
“These serious shortage protocols will allow pharmacists to supply an alternative form of penicillin, which will make things easier for them, patients and GPs.
“We are taking decisive action to address these temporary issues and improve access to these medicines by continuing to work with manufacturers and wholesalers to speed up deliveries, bring forward stock they have to help ensure it gets to where it’s needed and boost supply to meet demand as quickly as possible.”
The Royal Pharmaceutical Society (RPS) said pharmacists should be permitted to make minor changes to prescriptions without the need for a shortage protocol.
Thorrun Govind, chair of the RPS in England, said: “Ultimately we’d like to see a change in the law which makes the whole process of supply of medicines easier and quicker for both pharmacists and patients. We urge the Government to amend medicines legislation to allow pharmacists to make minor amendments to a prescription without any protocol being needed.
“At present a prescription can only be changed by the prescriber, which causes unnecessary workload for GPs and delays for patients.
“We want to see all pharmacists across the UK enabled to change prescriptions and be able to supply a different quantity, strength or formulation of a medicine (for example changing capsules to tablets) on a daily basis, to avoid unnecessary bureaucracy and the need for an SSP to be developed, signed and authorised by a minister.
“In effect it would mean that pharmacists can help patients straight away.”