TORONTO -- A published in The Lancet Infectious Diseases journal has identified a new strain of disease-causing bacteria which explains a rise in infections such as scarlet fever in England and Wales.

Scarlet fever, which most often affects young children with symptoms that include high temperatures, sore throats and a rough pink-to-red rash, is caused by the Streptococcus pyogenes bacterium, known as Strep A.

After a surge of thousands of cases of scarlet fever occurred in England from 2014 to 2016, researchers set out to 鈥渋dentify the Strep A strains causing infection鈥n England and Wales鈥 by studying the 鈥渆mm鈥 genes present, the Lancet said in a press release. 

鈥淓mm鈥 genes refer to the protein that encodes the surface of a cell to designate it as one of the Streptococcus pyogenes bacterium, .

Researchers hoped that by sequencing the 鈥渆mm鈥 genes, they could figure out the reason behind the biggest rise in scarlet fever cases since the 1960s. 

A particular gene known as 鈥渆mm1鈥 was designated as the 鈥渋ncreasingly dominant鈥 gene in the invasive infections recorded in England and Wales.

This discovery caused researchers to sequence all variations of the 鈥渆mm1鈥 bacterium and they 鈥渦ncovered a new strain of Streptococcus pyogenes with an increased capacity to produce scarlet fever toxin.鈥

"Given that this strain has an apparently enhanced ability to cause all types of Strep A infection, it is important to monitor the bacterium both here and globally," joint first author Dr. Nicola Lynskey, from Imperial College London, U.K., said in the release.

Researchers found that the new strain of Strep A, dubbed 鈥淢1UK鈥 produced 鈥渘ine times more toxin than other 鈥榚mm1鈥 strains鈥 and had been present in England as early as 2010.

The study speculates that the recent upswing of Strep A bacterium activity, coinciding with increased cases of scarlet fever 鈥渕ight have provided the conditions required for it to adapt genetically and spread within the U.K.鈥

Researchers also found strains of M1UK in 鈥渆mm1鈥 genes in Denmark and the U.S., which they say suggests it has the potential to spread internationally, but say it鈥檚 too early to know whether the new strain will be 鈥渟uited to environments in other countries鈥 due to differences in climate and disease control protocols.