Significant increase in cases
Between 1er January and May 31, 529 cases of invasive streptococcal A infection, likely to cause flesh-eating disease, have been reported in Quebec. This is a significant increase from the pre-pandemic years (2015 to 2019) when there were approximately 498 cases per year. “These invasive cases are serious cases, a dangerous form that can lead to amputations or death. It’s worrying,” says the Dr Donald Vinh, infectious disease specialist and microbiologist at the McGill University Health Center.
an invasive form
Group A streptococcus is a bacterium that circulates every year in Quebec and is commonly found in the throat or on the skin of individuals. A non-invasive infection can manifest itself in different ways, including pharyngitis, tonsillitis or a skin infection such as impetigo or scarlet fever.
However, some people will develop a so-called invasive infection, which can lead to serious and even fatal complications, such as flesh-eating disease, toxic shock syndrome or meningitis. “It is not known why some people develop the invasive form. It’s a mystery that remains, “says the Dr Vinh.
A rapidly progressing disease
Infected patients usually present to hospital with fever, nausea, vomiting, and a sore leg or arm that is purple or red in color. “The disease can progress within a few hours. A person can go from fine, to ugly, to dead very quickly,” says Dr.r Vinh. Since the beginning of the year, it is estimated that around 8% of those infected have died, indicated the Ministry of Health and Social Services (MSSS).
Children particularly affected
This significant increase in cases is particularly marked in children aged 6 months to 9 years. In the past five months, 64 cases have been reported, compared to an average of 35 cases for the years 2015 to 2019. Six young patients died from complications of the disease. In recent years, there have normally been fewer than five deaths per year among children. Because children are more susceptible to contracting strep A, primarily due to its spread at school, more of them develop invasive forms of the disease, says Dr.r Vinh.
Respiratory viruses possibly involved
The resurgence of respiratory viruses after the relaxation of sanitary measures could explain this increase in invasive infections, estimates the Ministry. Indeed, the rise in these infections generally follows a rise in the circulation of viral upper respiratory infections such as seasonal influenza. “A number of people who have had influenza are at risk of having the invasive form of streptococcus A in the following weeks,” explains Dr.r Vinh.
This increase in cases is not limited to Quebec: an increase is observable worldwide. “Some countries, like the Netherlands, have discovered a new strain that explains part of the increase,” says Dr.r Vinh. He does not exclude the possibility that this may also be the case in Quebec.
How to protect yourself?
Strep A is transmitted through respiratory droplets or through direct contact with the bacteria, such as through pus. Since there is no vaccine against these infections, good hygiene practices, such as washing hands and surfaces, can limit the transmission of these infections, explains the Dr Vinh.
To prevent infection, the Government of Quebec recommends cleaning wounds frequently and seeing a doctor if there are signs of infection such as redness, swelling, discharge or pain at the site of an injury.