'Advanced medicines still can't treat these': Deadly fungal infections a concern post-COVID-19, influenza
While fungi are not about to start turning the human race into zombies, like in the HBO blockbuster series The Last of Us, the World Health Organization (WHO) says invasive fungal infections are an increasing threat to human health.
Aspergillosis is one fungal infection common in our environment but, in some circumstances, it can turn deadly. In an average day, most of us will inhale hundreds to thousands of Aspergillus spores with no adverse effects, but for people with weakened immune systems it can cause deadly infections. That includes people undergoing cancer treatments, or bone marrow transplants, but it is now recognized that some viral infections, like influenza (flu) and SARS-CoV-2 (COVID-19) increase the risk of deadly fungal infection even in otherwise healthy people.
"When these kinds of things happen in the ICU, it can be devastating because even advanced medicines still can't treat these infections," said Dr. Bryan Yipp, an intensive care physician and researcher at the University of Calgary.
"Once many of these infections really get ingrained and take over, clearing them with medications alone, antifungal or anti microbials, can be very difficult."
Dr.Yipp began studying Aspergillus — a type of fungus that is a common mould — and its connection to viral infections in 2019, following three deaths in intensive care units of patients initially admitted for influenza, but who subsequently died of the fungal infection.
"It was very much a surprise when people first started identifying the fungus in the lung. There was a lot of discussion around the table of ICU doctors, infectious disease doctors, asking 'Was Aspergillosis really the cause of death, or was this just a secondary finding?'" said Yipp. "The pathologists who looked at the samples and the autopsies, were convinced that it was Aspergillosis that was the main problem."
UCalgary researchers have determined exposure to Aspergillus, a common fungal mould, can lead to a potentially dangerous Aspergillosis infection in people with weakened immune systems.
Working in Yipp's lab, lead researcher Nicole Sarden, a PhD candidate, isolated the mechanism by which the immune system starts failing to prevent fungal infections.
"In healthy humans. specific immune cells, called B cells, produce molecules (antibodies) that basically tag invaders so that other cells in the immune system, called neutrophils, can recognize them, eat them, and clear the infection," said Sarden
"But when you have infections with viruses, such as influenza, or if you get COVID, these molecules are no longer present, which means that the immune systems that are trying to eat, and clear the fungi cannot do it because they cannot see it."
Working with both mice and human blood and tissue samples, the researchers discovered that following a viral infection, neutrophils could identify a fungal infection and surround it but did nothing to destroy it.
"The virus kills the B cells, no messenger molecules exist, so the neutrophils that would normally attack, the fungus, are blinded. They sit there and don't know what to do," said Sarden.
The research team also discovered that reintroducing Aspergillosis reactive antibodies can protect infected mice, leading to hopes a similar treatment will be available in the near future for humans with Aspergillosis infections.
While Yipp and Sarden focused on Aspergillus, it is not the only fungus that can cause serious, or fatal infections. It is estimated fungal infections kill an estimated 1.5 million people worldwide every year. Most of those are due to four different fungi; Cryptococcus, Candida, Aspergillus, and Pneumocystis. Since the advent of COVID, a previously rare infection of the fungus Mucormycosis has been increasing rapidly in India. It affects the sinuses, brains and lungs of its victims. The rise in Mucormycosis has also been seen in patients who are recovering or have recently recovered from COVID.
Yipp is hopeful the research being conducted at Calgary's Cumming School of Medicine could lead to treatments for these infections as well.
"We have some hunches that that could be a similar mechanism to what we see here with what we have found." said Yipp. "So we think that this could be applied to multiple different types of fungi around the world."
The research team, led by Sarden, published their findings in the journal Science Translational Medicine.
CTVNews.ca Top Stories
![](https://www.ctvnews.ca/polopoly_fs/1.6978861.1722008569!/httpImage/image.jpg_gen/derivatives/landscape_800/image.jpg)
At least 4 buildings burned at Jasper Park Lodge, others damaged: Fairmont memo
The Fairmont Jasper Park Lodge said Thursday afternoon most of its structures are 'standing and intact,' including its iconic main lodge.
Major Canadian bank experiences direct deposit outage on payday
Scotiabank says it has fixed a technical issue that impacted direct deposits on Friday morning.
'He was just gone': Police ramp up search for vulnerable 3-year-old boy in Mississauga, Ont.
Police in Mississauga are conducting a full-scale search of the city’s biggest park for a non-verbal toddler who went missing Thursday evening. Sgt. Jennifer Trimble told reporters Friday morning that there has been no trace of three-year-old Zaid Abdullah since 6:20 p.m., when he was last seen with his parents in Erindale Park, near Dundas Street West and Mississauga Road.
Sask. appeal court says anti-trans group cannot join constitutional dispute over pronoun law
Saskatchewan’s Court of Appeal has denied a political group that opposes so-called “gender ideology” intervener status in a legal dispute over the province’s controversial pronoun law.
Justin Timberlake's attorney disputes he was intoxicated when arrested for DWI
A hearing in the case of Justin Timberlake being accused of driving while intoxicated was held Friday, where an attorney for the singer disputed his arrest in June.
Elon Musk's estranged daughter calls out his 'entirely fake' claims about her childhood
Vivian Jenna Wilson, Elon Musk's estranged daughter, publicly refuted several recent anti-trans statements her Tesla CEO and X owner father has made about her.
What we know about 'malicious' attack on French train network ahead of Olympics opening
French transport was thrust into chaos Friday just hours ahead of the Olympics 2024 opening ceremony after a series of co-ordinated 'malicious acts' upended high-speed train lines.Here's what happened and what we know so far.
Reported rate of child pornography increased 52% in 2023, total crime up 3%: Statistics Canada
Last year, reported child pornography cases increased by more than 50 per cent in Canada, in part due to more cases being sent to police by specialized internet child exploitation units, according to a Statistics Canada report.
Driver charged after flashing high beams at approaching police
Orillia OPP arrested and charged a driver with impaired driving after flashing their high beams.