(Photo : Photo by Tomohiro Ohsumi/Getty Images)
NAGOYA, JAPAN - FEBRUARY 06: Employees inspect disposable face masks on the production line of the Yokoi Co. Ltd. factory on February 06, 2020 in Nagoya, Japan. Yokoi, one of major mask manufacturers operating in Japan, said they received more than 20 times the normal orders for disposable face masks this month, due to the mask shortage in the country. Japan confirmed 45 cases of Wuhan coronavirus as the number of those who have died from the virus, known as 2019-nCoV, in China climbed to over 563 on Thursday, cases have been reported in other countries.

In an addition to the increasing conspiracy theories about wearing facemasks, a social media post claiming that reused facemasks could cause the transmission of a respiratory illness which can cause a rare and fatal type of pneumonia known as Legionnaires' disease.

The said theory claims that respiratory droplets which may contain the causative agent of Legionnaires' disease, Legionella pneumophila, may thrive in the contaminated respiratory droplets that are in the used face masks. The said post also purported that an anonymous woman who wore a mask on a daily basis was misdiagnosed with COVID-19 due to the "moisture and bacteria" that were held in her mask.

However, fact-checking site snopes.com verified the information and tagged the claims as false. According to them, a non-profit research organization about Legionnaires', Legionella stated that the disease is not contagious and that it cannot be transmitted by people infected or from their masks.

On Legionella's website, they stated that Legionnaires' cannot be contracted through facemasks, rather it is a bacterium that is transmitted through breathing in water droplets or aspirating drinking water. It also clarified that the disease is not spread from human-to-human in respiratory droplets neither does it survive on surfaces that are dry, emphasizing that face masks cannot be a sources for Legionella bacterial infection.

Legionnaires' disease is characterized by cough, headache, fever and shortness of breath which are also the same symptoms associated with COVID-19, thus it could result to misdiagnosis.

Aside from this, the disease also causes a severe lung infection which can be contracted through breathing in contaminated mist or water. However, unlike COVID-19, Legionnaires' can be treated with antibiotics, but is still considered fatal to 1 out of 10 people.

It has also been emphasized by Legionella that Legionnaires' is never considered as a consequence of wearing facemasks. This is because one has to directly inhale contaminated water or mist before getting infected. Moreover, it can only survive in standing water and not on dry surfaces.

Back in May, a guidance was issued by the United States Centers for Disease Control and Prevention regarding the reopening of buildings, schools and other facilities after they were shut down amid the COVID-19 pandemic. The closures of the facilities were connected to the possible pooling of water systems that could have been the primary culture places of the Legionella bacterium.

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The fact-checking site was not able to find the radio show that was referenced by the social media posts, however, they were able to track down the source of the rumor in a published story in Naples Daily News. Based on the report, there were four people from Florida who were diagnosed with mask-related Legionnaires' disease. But the hospital that was mentioned in the report denied such claims.

On top of this, the CDC still cautioned that people who are at risk of contracting Legionnaires' are those who are with weak immune system. Thus, they are advised to consult with professionals before getting exposed to places with possible contamination such as public toilets that have not been recently cleaned. The agency even noted that face masks can even limit the risk of Legionella bacteria infection.

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