Covid-19. Beware of the “Black Fungus”

The Covid-19 pandemic continues to shake us daily with new and unexpected developments: new strains are emerging, along with diseases caused by opportunistic organisms that take advantage of weakened immune systems. This is the case with the so-called "black fungus," which has been reported primarily in India but has also been detected in the United Kingdom, the United States, France, Austria, Brazil, and Mexico.

Mucormycosis is an infection caused by exposure to fungi of the Mucorales family, commonly found in soil, plants, manure, and decaying fruits and vegetables. When the fungal spores are inhaled from the air, they can affect the sinuses, brain, and lungs, and can be life-threatening in people with diabetes or severe immunosuppression, such as cancer patients or people with HIV/AIDS. It is known as "black fungus" because it leaves a black stain at the site of tissue death.

Mucormycosis is believed to be triggered by steroid use. These medications are used to reduce lung inflammation caused by COVID-19 and appear to help prevent some of the damage that can occur when the immune system overreacts to fight the coronavirus. However, they also lower immunity and increase blood sugar levels in both diabetic and non-diabetic patients who contract COVID-19. This decreased immunity could leave the body vulnerable to this fungus or any other opportunistic microorganism.

The infection commonly manifests during the illness or in the post-recovery stages, so it could be considered part of the symptoms of the aftereffects of COVID-19. Despite the difficulties the infection presents, its prevention is quite simple: ensuring that coronavirus patients, both during treatment and after recovery, receive the correct dose of steroids for an appropriate duration. And if, despite these measures, the patient contracts this infection, an intravenous antifungal injection administered daily for up to eight weeks is an effective treatment.

Patients with this fungal infection typically experience nasal congestion and bleeding, eye swelling and pain, drooping eyelids, blurred vision, and eventually, vision loss. Black patches of skin may also appear around the nose. It is crucial that patients seek treatment promptly, before vision loss occurs, as the eye must be surgically removed to prevent the infection from spreading to the brain. In some cases, patients lose vision in both eyes. And in rare cases, doctors may have to remove the jawbone to prevent the disease from spreading and causing death.

Doctors treating patients with Covid-19, diabetes, and weakened immune systems should be alert to early symptoms, such as pain in the Sinus congestion or blockage on one side of the face, one-sided headache, swelling or numbness, toothache, and loose teeth. The disease can also cause blackening or discoloration of the nose, blurred or double vision, chest pain, shortness of breath, and coughing up blood.

It is important to be vigilant with patients suffering from coronavirus because they could develop complications from opportunistic infections, especially if they are diabetic, receiving steroid treatment, or exhibit symptoms such as sinusitis that does not respond to antibiotics. In these cases, time is crucial to prevent the disease from progressing and having a fatal outcome.

It's difficult to avoid contact with microorganisms like fungi, which are practically everywhere, making prevention more challenging. Let's keep in mind all the well-known measures to prevent COVID-19 from exacerbating other illnesses: maintain a healthy diet to protect your immune system, manage diabetes or any other health conditions you may have, and never self-medicate.

Ramona Ávila Núñez, PhD

Reference

Mehta S, Pandey A. Rhino-Orbital Mucormycosis Associated With COVID-19. Cureus. 2020 Sep 30;12(9):e10726. doi: 10.7759/cureus.10726. PMID: 33145132; PMCID: PMC7599039.