Scarlet fever is back in the 21st century
Scientists have yet to discover a reason for the fever’s return, but its virulence has diminished
In cases of scarlet fever, the child will have a distinctive sandpapery, red rash, which usually first appears on the chest and stomach
A hint of Victorian times has crept into medicine of late. Scurvy, whooping cough and most-recently, scarlet fever have reappeared. In the UK, cases of scarlet fever have reached a 50-year high, with numbers back to levels last seen in the 1960s.
Fevers were much feared by parents and health professionals in the pre-antibiotic era. Scarlet fever was a leading cause of infant deaths in the early 20th century. Scour old historical records and you will find references to fever hospitals in many large Irish towns. They were built in order to isolate patients with highly infectious scarlet and typhoid fevers from the rest of the community.
A fever epidemic of unprecedented proportions raged in Ireland between 1816 and 1819, prompting legislation establishing local boards of health and grand juries, which were empowered to raise funds to build fever hospitals. Even in the latter decades of the 19th century, case-fatality rates for scarlet fever were very high; one textbook refers to a fatality rate of 55 per cent in children under one year.
While person-to-person spread of streptococcal infections (the bacteria that causes scarlet fever) was the main vehicle for epidemics, contaminated milk was also shown to produce explosive epidemics of very acute streptococcal pharyngitis with a high mortality. By the end of the 19th century, scarlet fever had overtaken diphtheria as a cause of death, occurring with great frequency and often with high case-fatality rates. An 1894 textbook of paediatrics described scarlet fever as the most widely disseminated of the childhood infections and “the most dreaded of all the diseases of children”.
Scientists have yet to figure out a reason for scarlet fever’s return.
“The scarlet fever that would have been around in the Victorian era is a completely different beast to what we see now,” according to Dr Theresa Lamagni, Public Health England (PHE)’s head of streptococcal infection surveillance. It was a very severe infection that led to a lot of childhood deaths, but over the course of the last century its virulence has diminished considerably
An interesting theory is that a bacteria evolves to become weaker over time because it will not be passed on if it rapidly kills its host, and scarlet fever was diminishing in force before the advent of modern antibiotics. And there is no evidence that the infection has developed an increased resistance to antibiotics, or that it is now a virulent new strain.
Not the most difficult clinical diagnosis by any stretch, scarlet fever announces its presence with a distinctive sandpapery, red rash, which usually first appears on the chest and stomach. The child – usually between the age of two and eight – will also have a high temperature, sore throat and a swollen tongue.
The rash is typically most noticeable in the creases of the joints and over the stomach and feels rough to touch like sandpaper. The tongue can develop a white coating which then peels leaving the tongue red and swollen , a typical appearance which is often described as “strawberry tongue”.
Scarlet fever is usually a mild infection. However, complications such as ear infection, throat abscess, and pneumonia can occur. And very rarely more severe complications causing kidney or heart damage can occur – which can be prevented by prompt treatment with antibiotics.
Group A streptococci (GAS) are still sensitive to penicillin and require a full 10-day course of the antibiotic. If you are diagnosed with scarlet fever you should not attend crèche, school or work until 24 hours after starting antibiotics to avoid spreading the infection.
GAS bacteria also cause “strep throat” and skin infections such as impetigo. Rarely, they cause more invasive disease such as streptococcal toxic shock syndrome, necrotising fasciitis, and sepsis syndrome.
Scarlet fever and the other milder infections caused by GAS bacteria are not notifiable here. Because of this the number of cases in the Republic is not known.