Lamagni T, et al. - This trial was executed in order to gauge the clinical and epidemiological patterns of scarlet fever in England. Additionally, experts intended to determine its potential causes. An unprecedented rise of scarlet fever was brought to light in England, displaying the highest incidence for approximately 50 years. However, the causes for its rise remained unknown. Detection of its causes presented as a public health priority.

Methods

• The scheme of this research was a population-based surveillance study.
• Herein, statutory scarlet fever notifications held by Public Health England were inspected from 1911 to 2016 in England and Wales in order to determine the periods of sudden escalation of scarlet fever.
• A scrutiny and comparison were carried out of the characteristics of cases and outbreaks in England including frequency of complications and hospital admissions with the pre-upsurge period.
• During this research, isolates from throat swabs were obtained and were emm typed.

Results

• Data retrieval was performed between Jan 1, 1911, and Dec 31, 2016.
• A rise was noted in the population rates of scarlet fever by a factor of three between 2013 and 2014 from 8·2 to 27·2 per 100,000 (rate ratio [RR] 3·34, 95% CI 3·23-3·45; p < 0·0001).
• Findings revealed additional increases in 2015 (30·6 per 100,000) and in 2016 (33·2 per 100,000), displaying the highest number of cases (19,206) and rate of scarlet fever notification since 1967.
• It was determined that the median age of cases in 2014 was 4 years (IQR 3-7) exhibiting an incidence of 186 per 100,000 children under age 10 years.
• Data illustrated increased incidence in all parts of England, with 620 outbreaks reported in 2016.
• Between 2013 and 2016, hospital admissions for scarlet fever increased by 97%.
• The rate of admission was 1 in 40 cases for the management of the condition or potential complications.
• As per the findings, a diversity of emm types were detected through the assessment of strains (n=303), with emm3 (43%), emm12 (15%), emm1 (11%), and emm4 (9%) presenting as the most common.
• Four-yearly periodicity was detected by the longitudinal analysis in the population incidence of scarlet fever of consistently lower magnitude when compared to the current escalation.