COVID-19 creates ideal conditions for drug-resistant strains in Brazil

The situation with COVID-19 in Brazil has opened the door to the emergence and epidemic of relatively new fungi that are rapidly showing signs of becoming drug-resistant “superfungi.” Fungal journal..

Researchers have detected since December 2020 Candida auris Nine patients at a hospital in Salvador, northeastern Brazil.

Usually a genus fungus Candida It is relatively harmless and most often causes treatable vaginal yeast infections and oral candidiasis. However, the mortality rate is close to 60%, Candida auris Patients with SARS-CoV-2 have different symptoms and are ideal targets.

Candida auris It can enter the bloodstream and cause a systemic infection known as candidaemia, which resembles bacterial sepsis. Invasion of the bloodstream and poor response of the immune system to pathogens can damage several organs and eventually lead to death.

“This species is not very sensitive to disinfectants used in hospitals and clinics,” said Arnaldo Colombo, lead author of the new study and director of the Institute of Special Mycology at the Federal University of São Paulo (UNIFESP). explained. , It can survive in hospitals, where it colonizes healthcare professionals and eventually infects patients with severe COVID-19 and other important patients with long-term stays. “

Of the nine patients in the hospital, Colombo said some had shown colonization of the fungus and others were infected and symptomatic.

“We are monitoring the evolutionary characteristics of Candida auris Samples that have been isolated from patients in Salvador hospitals and have reduced susceptibility to fluconazole and echinocandin have already been found. The latter belongs to a major class of drugs used to treat invasive candidiasis, “says Colombo.

In fact, Colombo and his team have been testing hospital samples of antifungal susceptibility every month since December 2020. In a recent sample, researchers were able to inactivate the culture last year, and even earlier this year.

“Like many antibiotic-resistant bacteria, the mechanism by which a species develops drug resistance is not enzymatic degradation. Fungi develop structural changes in the proteins to which the drug binds and block the cell wall. The key synthesis of survival. “

UNIFESP’s Colombo group is now working with a Dutch colleague to sequence the fungus and confer drug resistance on the gene. Candida auris It has been mutated from December 2020 to the present.

Candida auris It was first separated in Japan in 2009, in Asia and Europe in 2011, in the Americas, Colombia, Panama, Chile in 2016, and in Brazil in 2020. So far, five clades or strains of fungi have been described.

According to Colombo, the salvador-isolated clades are more similar to the original Asian clades than the variants found in Venezuela and other South American countries, suggesting the second independent arrival of superfungi on the continent. I am.

“Or, there may be local sources of the environment, as none of the Brazilian patients infected with the fungus have traveled abroad or been infected with relatives,” Colombo said.

Due to the second wave of COVID-19 infection in Brazil, the research team is particularly concerned about hyperfungi, regardless of origin.

“In the near future, over-occupancy and limited resources for infection control practices, such as long-term use of personnel protection due to shortages, Candida auris To spread invasive devices, form colonies, and explode medical-related infections, “the team concludes.

Photo: Fluorescence microscope image showing morphology Candida auris.. credit: João Nóbrega Almeida Júnior / UNIFESP