'Upsurge' of scarlet fever in England, study warns

Scarlet fever, a common cause of childhood death in the 1800s and early 1900s, has seen an upsurge in England since 2011 after decades of decline, scientists said.

File image. (AAP) Source: AAP

Identifying the cause for the increased cases was "a public health priority", they warned.

"England is experiencing an unprecedented rise in scarlet fever with the highest incidence for nearly 50 years," said a study published in The Lancet Infectious Diseases, a leading medical journal.

In 2014, that amounted to a scarlet fever notification "for one in 500 children under the age of 10 years." There were no deaths.

"Whilst current rates are nowhere near those seen in the early 1900s, the magnitude of the recent upsurge is greater than any documented in the last century," said study leader Theresa Lamagni of Public Health England, Britain's executive health agency.

Scarlet fever is an infection, usually not serious, with symptoms including a sore throat, headache, high temperature and an itchy, sandpaper-like rash for which the disease is named.

Caused by the Streptococcus pyogenes bacteria, it is most common in children under 10, and can be treated with antibiotics. 

It killed thousands of people in the Victorian era, but has become much less feared since the advent of antibiotics.

Still, in rare cases it can lead to pneumonia, sepsis, and liver and kidney damage, the research team said.

Looking at scarlet fever notifications in England and Wales from 1911 onwards, they uncovered a sevenfold increase in new cases from 2011 to 2016.

There were 620 outbreaks in 2016 with more than 19,000 cases, mostly in schools and nurseries.

From 2013 to 2014, scarlet fever incidence tripled from 8.2 infections per 100,000 people to 27.2, the team found.

Hospitalisations almost doubled from 703 in 2013 to 1,300 in 2016.

The reason for the "ongoing rise" in cases is not known, the team said. Genetic testing has found there was no new strain of easily transmissible bacteria behind the surge.

The quest for an answer continues.

In the meantime, people with scarlet fever symptoms "should see their GP promptly as they will require antibiotic treatment to reduce the risk of complications," the team said.

"Antibiotic treatment also reduces the likelihood of the infection being passed on to others."

Vietnam, China, South Korea and Hong Kong have also reported an escalation in the past five years, the researchers said, but no other European country has reported a sudden rise.