Can Over-Steaming Cause Black Fungus? Here’s What You Didn’t Know

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One advice that is often given to people with a blocked nose or someone who has a cold, cough or even the onset of a cold, is to do steam inhalation. However, there are now reports that suggest that ‘over-steaming’ might lead to the occurrence of Black Fungus.

Mucormycosis, also known as Black Fungus, is an infection that has impacted at least 7,250 people in India and killed at least 219 people. In an urgent attempt to bring this outbreak under control, the Central government has said the states should declare the disease notifiable under the Epidemic Diseases Act, 1897.

Dr Mansi Bajaj Malik, a Consultant Physician at Vista Eye Care in West Delhi helps us understand the correlation between over-steaming and the occurrence of Black Fungus.

1. What is the impact of steam inhalation — before and after testing positive for COVID-19?

Dr Mansi: Steam inhalation is an age-old home remedy often used to relieve nasal congestion, throat irritation and also open up the nasal passages in common cold and sinus infections.

It helps in symptomatic relief in COVID-19 patients who are suffering from symptoms like stuffy or blocked nose, or patients suffering from ‘Post Nasal Drip’. (Secretions from the nose that drain down into the throat, causing congestion and cough. ‘Post Nasal Drip’ is usually caused by allergies or the common cold.)

However, beyond the symptomatic relief, its benefit is doubtful.

2. What is ‘over-steaming’? How much should one resort to steam inhalation in a day?

Dr Mansi: Steam inhalation is usually recommended for 10-15 minutes per session for a maximum of 2-3 times a day. Anything over and above that could be considered to be over steaming.

3. As steam inhalation is an age-old practice, why is Black Fungus only occurring now?

Dr Mansi: Black fungus is not a new disease either. It is a rare, but a serious infection seen almost exclusively in immunocompromised individuals and patients with diabetes. With high prevalence of diabetes in our country, often uncontrolled and increased usage of oral steroids in management of COVID-19, the cases are on the rise.

Contaminated vaporisers and humidifiers, along with steam inhalation might be a contributing factor but that needs to be investigated further.

4. Can over-steaming cause Black Fungus? Should one be worried?

Dr Mansi: Black Fungus or mucormycosis is a fungal opportunistic infection. Like any disease, there are three factors that lead to its manifestation:

• Host factors
• Pathogen
• Environment.

In this case, the pathogen is a fungus which is naturally found in the environment but it gets the opportunity to grow in the host (i.e. humans) mainly under conditions like uncontrolled diabetes, immunocompromised state and neutropenia — a condition in which you have lower-than-normal levels of neutrophils, a type of white blood cell, in your blood.

Steam inhalation can contribute in creating a warm and damp environment for the fungus but that alone is unlikely to cause the disease. It is likely to occur only in circumstances like high sugar levels or with usage of steroids, antibiotics and patients in immunocompromised states.

5. Is it advisable to use the same steam machine within one household?

Dr Mansi: In a non-COVID-19 scenario, steam machines could be shared in a household. But in COVID-19 positive cases, there are high chances of the machine being contaminated with the patient’s nasal secretions that can contribute to the spread of the infection. It is therefore not advisable to share a steam machine in a COVID-19 environment.

6. Should we be using distilled water when steaming?

Dr Mansi: Distilled water is preferred for long term maintenance of the machine. Tap water tends to leave deposits in the water container which can provide a milieu for growth of microbes like fungi.

7. What should we watch out for when we clean our steamers?

Dr Mansi: Ideally, steam vaporisers should be cleaned after every use. Empty unused water from the container, rinse it thoroughly with water, drain it and wipe with a dry, clean cloth. Repeat this process after every use.

(Edited by Yoshita Rao)