Despite having been largely eliminated from countries for almost a century, outbreaks of the childhood disease known as scarlet fever (scarlatina) have been tracked in Europe and Asia in the past five years.
Scientists from the University of Queensland (UQ) and other research organizations made use of genome sequencing methods to examine a resurgence of the scarlet fever-causing bacteria called group A Streptococcus and the organisms' increased resistance to antibiotic treatment.
Professor Mark Walker, a researcher from UQ's School of Chemistry and Molecular Biosciences, said cases of group A strep have been detected in the UK as well as in several Asian countries.
"We have not yet had an outbreak in Australia, but over the past five years there have been more than 5000 cases in Hong Kong (a 10-fold increase) and more than 100,000 cases in China," Walker said.
"An outbreak in the UK has resulted in 12,000 cases since last year."
According to the Centers for Disease Control and Prevention (CDC), scarlet fever can affect individuals from different age groups, but the disease is mostly seen in children between 5 years old and 12 years old.
People infected with the group A strep bacteria often develop fever, headache, sore throat, nausea and red skin rash.
Dr. Nouri Ben Zakour, Walker's colleague at UQ, said that the findings of their study are very concerning.
She said the nature of scarlet fever could very well change and the disease could become more resistant to treatments typically prescribed for patients suffering from infections of the respiratory tract.
Patients who did not have allergic reactions to penicillin continued to benefit from the treatment.
Ben Zakour pointed out that a resurgence of scarlatina cases could pre-empt a potential increase in cases of rheumatic heart illness, which can cause individuals to suffer permanent damage to their heart.
The researchers note that improved awareness of the disease can now allow them to quickly identify bacteria associated with scarlet fever as well as elements that lead to resistance to antibiotics. They can also monitor the spread of group A strep strains that cause the fever.
While they have yet to determine the evolutionary forces that could be causing the recent outbreaks, Ben Zakour said several factors could play a role in spreading the disease such as bacterial causes and the strength of people's immunity to illnesses.
Environmental variables such as the amount of rainfall and temperature could also influence the spread of scarlet fever.
The findings of the international study are featured in the journal Scientific Reports.
