Readers like you keep news free for everyone.

More than 5,000 readers have already pitched in to keep free access to The Journal.

For the price of one cup of coffee each week you can help keep paywalls away.

Support us today
Not now
Sunday 24 September 2023 Dublin: 16°C
Debunked: No, you cannot catch Legionnaires' disease or pleurisy from wearing a face covering
There have been fewer cases of legionella infection in Ireland this year compared to last year.

A CLAIM THAT has been widely circulated by Irish users on Facebook in recent days speculates that recent spikes in Covid-19 infection may instead be Legionnaires’ disease caused by mask wearing.

Many of the posts, which have also been shared in the US over the past week, reference a caller to a radio talk show recently whose wife was told she had Covid-19, then later informed she actually had Legionnaires’ disease from “the moisture and bacteria in her mask”. has looked for any references to a radio talk show in Ireland in which a caller told this story about his wife and has found no evidence that it happened. 

US factchecking website Snopes also tried to identify the radio talk show but could find no mention of it or evidence that it existed. (If we’re wrong and you have a link to this show, send it our way). 

Another similar post suggests wearing a mask could give a person pleurisy.

Let’s start with Legionnaires’ disease

This is a type of pneumonia which can cause serious illness in people aged over 50 years, smokers, and those with underlying health conditions. Both Legionnaires’ disease and its milder form, Pontiac fever, are caused by the growth of Legionella bacteria in water systems which are not adequately managed.

A person can catch Legionnaires’ disease if they breathe in tiny droplets of water containing bacteria that cause the infection. People are most at risk in places like hotels, hospitals or offices where the bacteria got into the water supply. It is very rare to catch it at home.

People usually get it from drinking water containing the bacteria, from other people with the infection or from places like ponds, lakes and rivers.

The fatality rate of the disease is about 10%. The illness usually starts with flu-like symptoms including fever, tiredness, headache, and muscle pains. This is followed by a dry cough and breathing difficulties that may progress to a severe pneumonia. 

Why the link between Covid-19 and the disease?

The posts appear to be tied in with the general misinformation around the wearing of face coverings.

There have been legitimate reports recently about Legionnaires’ disease, none of which linked it to masks. 

A widely-shared article published by US radio broadcaster Georgia Public Broadcasting last weekend pointed to similarities between the symptoms of Legionnaires’ disease and those of Covid-19, such as shortness of breath, cough and fever. 

The piece also includes expert commentary on potential risks associated with the recent shutdown of hotels, schools and office buildings that could lead to stagnant water in the lines.  

In May, the HSE’s Health Protection Surveillance Centre (HSPC) issued a similar caution.

The HSE said it could be caused due to bacteria growth in appliances which have been left untouched due to the Covid-19 pandemic. Due to the current pandemic, many buildings have been closed, or their use restricted.

“This can increase the risk of Legionella growth in the water systems and associated equipment including evaporative air conditioning systems, water fountains, showers, spa pools, and other equipment if the water systems have not been managed adequately,” the HSE said.

However the HSE made no link between Covid-19 symptoms and those of Legionnaires and did not point to an increase in the number of cases. It was simply a warning ahead of a return to work for some businesses. 

The HSE has said a person cannot contract the illness from wearing a face covering – and in fact cases of legionella infection are lower this year compared to 2019. 

A spokesperson for the HSE this week told there is “no link between wearing a mask and an increased risk of legionella infection”.

“Legionella is found in the environment and is not transmitted from person to person or by re-breathing one’s own respiratory secretions,” they said.

The HSE also pointed out that the number of legionella notifications in 2020 (weeks 1-31) is seven, this compares to 15 cases notified for the same time period in 2019.

There is therefore no evidence of increased notification of legionella infection in Ireland in 2020., a US organisation, has also said people cannot contract Legionnaires’ disease from wearing face masks – even if they haven’t been washed:

“Legionella bacteria is transmitted by aspirating drinking water or breathing in water droplets. Legionella is not spread from person-to-person in respiratory droplets nor does the bacteria survive on dry surfaces. Your mask would not be a source of transmission for the Legionella bacteria.”

What about pleurisy?

Pleurisy is an inflammation of the lining around the lung. The most common symptom is a sharp chest pain that feels worse when breathing.

Causes include a viral infection, such as flu, a bacterial infection, such as pneumonia, a blood clot blocking the flow into the lungs and lung cancer.

In early July, similar posts in the US claimed a healthy 19-year-old shop worker was diagnosed with pleurisy due to wearing a mask for over eight hours a day for five or six days a week, “breathing in her own bacteria”.

“There is absolutely no truth in that claim,” said Humberto Choi, a pulmonologist at Cleveland Clinic, told Associated Press.

“There are thousands of health care workers wearing face masks everyday including masks that are much tighter than simple surgical masks. Nobody is getting pleurisy because of that.”

Albert Rizzo, chief medical officer at the American Lung Association, also told AP that the claims are “a reach”.

“I don’t see a medically plausible mechanism for mask wearing to cause pleurisy,” he said.

Proper use of face coverings

The wearing of face coverings is now mandatory on public transport in Ireland and will be mandatory in shops and shopping centres from Monday. 

Health experts have said proper use of masks is important to avoid contamination and to best protect those around you. 


  • Make sure it fits well over your mouth and nose with no gaps, and is comfortable;
  • Clean your hands before you put it on;
  • Tie it securely;
  • Carry your mask in a clean waterproof bag;
  • Remove it from behind – don’t touch the front of it;
  • Wash your reusable face coverings regularly – it may help to have a few in rotation;
  • Put your disposable masks in the bin after each use.


  • Don’t touch a mask or face covering while wearing it – clean your hands properly if you have to touch it;
  • Don’t use a damp or wet medical mask or reuse a medical mask;
  • Don’t share masks;
  • Don’t lower your mask to speak, eat or smoke – if you need to uncover your nose or mouth, it’s better to take the mask off entirely for a short time and place it back in its plastic bag;
  • Don’t discard disposable masks in public places – use a bin.


There is a lot of false news and scaremongering being spread in Ireland at the moment about coronavirus. Here are some practical ways for you to assess whether the messages that you’re seeing – especially on WhatsApp – are true or not. 


Look at where it’s coming from. Is it someone you know? Do they have a source for the information (e.g. the HSE website) or are they just saying that the information comes from someone they know? A lot of the false news being spread right now is from people claiming that messages from ‘a friend’ of theirs. Have a look yourself – do a quick Google search and see if the information is being reported elsewhere. 

Secondly, get the whole story, not just a headline. A lot of these messages have got vague information (“all the doctors at this hospital are panicking”) and don’t mention specific details. This is often – but not always a sign – that it may not be accurate. 

Finally, see how you feel after reading it. A lot of these false messages are designed to make people feel panicked. They’re deliberately manipulating your feelings to make you more likely to share it. If you feel panicked after reading something, check it out and see if it really is true.’s FactCheck is a signatory to the International Fact-Checking Network’s Code of Principles. You can read it here. For information on how FactCheck works, what the verdicts mean, and how you can take part, check out our Reader’s Guide here. You can read about the team of editors and reporters who work on the factchecks here

Have you gotten a message on WhatsApp or Facebook or Twitter about coronavirus that you’re not sure about and want us to check it out? Message or mail us and we’ll look into debunking it. WhatsApp: 085 221 4696 or Email:

Your Voice
Readers Comments
This is YOUR comments community. Stay civil, stay constructive, stay on topic. Please familiarise yourself with our comments policy here before taking part.
Leave a Comment
    Submit a report
    Please help us understand how this comment violates our community guidelines.
    Thank you for the feedback
    Your feedback has been sent to our team for review.

    Leave a commentcancel