Black mold: a deadly new infection takes over the world

2024 Author: Seth Attwood | [email protected]. Last modified: 2023-12-16 15:55

In India, against the backdrop of a powerful wave of COVID-19, thousands of cases of mucormycosis, a dangerous fungal disease, are recorded. In severe cases, doctors remove the eyes and parts of the face to save life. The infection is difficult to treat due to antifungal drug resistance.

We figure out who is at risk and whether it is worth fearing the disease in Russia.

In the kingdom of mold

We are surrounded by millions of microbes. We breathe in, eat, carry viruses, bacteria, molds on our skin. They are not dangerous for a healthy body, but as soon as it fails, an invisible enemy attacks. Fungal infections are especially insidious: they are asymptomatic, difficult to treat, usually lasting for months, and have severe side effects. It affects people who already have serious health problems: HIV, cancer, organ transplantation, diabetes, extensive wounds, burns. The mortality rate for fungal invasions is very high.

Pathogenic mucorous fungi, candida yeast, aspergilla molds. Although some of their representatives are useful in science, medicine, and also in everyday life, they are used in experiments as experimental organisms, as a ferment, to obtain antibiotics. They live in soil, on diseased plants, walls of rooms with high humidity, and also form fluffy colonies on various plant substrates. Fungi multiply by microscopic spores, from which mycelium (mycelium) and hyphae grow, drawing water and nutrition from the environment.

An outbreak at a covid hospital in the United States

In 2009, at a hospital in Tokyo, a previously unknown species of the pathogenic fungus Candida auris was isolated from the ear of an elderly woman with otitis media. Later, similar cases were confirmed in another 15 patients. Candida auris has proven to be an extremely aggressive, multidrug-resistant pathogen, and contagious. Its origin and natural focus have not yet been determined.

The infection quickly spread throughout the world. In 2017, it was first diagnosed at a hospital in Florida (USA) and exceptional measures were taken to prevent spread: even the contacts of the infected were tracked. During the pandemic, patients with COVID-19 began to be admitted to the hospital, and in July 2020, four cases of Candida auris were identified among them.

All patients were checked. Of the 67 people in the covid department, 35 were found to have antibodies to the pathogen. Eight died within the next month, but it is impossible to say what the contribution of the fungal disease is. Scientists believe that the germ was spread on staff clothing and mobile medical equipment that were not properly disinfected.

Dual epidemic in India

Mukorovye fungi have been known since the 19th century - then they began to be isolated from sick animals. They live in soil, plants, manure, rotting fruits. Those who are closer to the ground, for example, dogs, who constantly sniff everything, encounter it.

Mucormycosis occurs as complications after chemotherapy. Usually, if a patient has lymphocytes below a critical level in a blood test, anti-fungal therapy is started for prophylaxis. However, especially insidious microbes bypass it. Then the last resort is the antibiotic amphotericin obtained from bacteria. The drug has dire side effects, which is why medicine is in desperate need of new antifungal drugs and vaccines.

Spores of mucorous fungi penetrate the nasopharynx, settle in the sinuses, grow, release hyphae and produce toxins that decompose tissues and bones. Visually, the hyphae are black, hence the name of the disease - black mold. The infection enters the skull, blocks the main arteries and veins, and causes bleeding.

Before the pandemic, mucormycosis was extremely rare in humans. However, there has been a real outbreak in India amid a powerful wave of COVID-19. Two hundred thousand new cases are detected there per day. Explosive growth is associated with a special, Indian, variant of the coronavirus. This is superimposed on a fungal infection in discharged or recovering patients. More than half of the cases of the exotic disease occur in the western states of Gujarat and Maharashtra.

Since it is very difficult to recognize mucormycosis on their own, people go to doctors with advanced forms, when immediate surgical removal of tissues, eyes and jaws is required. Otherwise, the mortality rate is almost one hundred percent.

Many people associate an outbreak of mucormycosis with the use of steroids in the treatment of critically ill patients with COVID-19. These anti-inflammatory drugs actually save lives, but they suppress the immune system. Unlike Candida Auris, mucormycosis is not transmitted from person to person or from an animal - it can be obtained from the environment by inhaling spores. It is possible that ventilators and the use of oxygen contribute to the invasion. But these are just versions.

It is no coincidence that India is at the epicenter of a double viral-fungal epidemic. In countries with a tropical climate, the concentration of spores in the environment is immeasurably higher than, say, in the temperate zone. In Russia, due to natural and geographical factors, an outbreak of black mold can be avoided, according to Rospotrebnadzor.