Drug-resistant mold spreads and turns out to infect the lungs of sensitive people

A new study led by Imperial College London found that drug-resistant mold spreads from the environment and infects the lungs of sensitive people.

Researchers have found six people infected with a drug-resistant strain called Aspergillus fumigatus, which can be traced back to spores in the environment. Their findings use samples from England, Wales, Scotland and Ireland. Nature microbiology..

Aspergillus fumigatus is an environmental mold that can cause fungal lung disease. People with healthy lungs get rid of inhaled spores, but people with weakened lung condition or immunity sometimes cannot. That is, spores can remain in the lungs and cause an infection called aspergillosis. Aspergillus affects 10 to 20 million people worldwide. Infections are usually treated with antifungal drugs, but new resistance to these drugs has been reported.

Researchers say this resistance has evolved due to the widespread use of azole fungicides in agriculture. Because similarly functioning azole drugs are the first-line treatment for patients infected with Aspergillus fumigatus scab, exposure of the fungus to azole bactericides in the environment is often even before it is encountered. It means that it is in the form of drug resistance, the people it infects.

Researchers are seeking increased monitoring of Aspergillus fumigatus in the environment and clinics to help them understand the risks posed by Aspergillus fumigatus.

Professor Matthew Fisher, Senior Author of the Imperials School of Public Health, said:

He adds: “The prevalence of drug-resistant aspergillosis has increased from negligible levels before 1999 to up to 3-40% of cases across Europe today. Immunosuppressive therapy receiving stem cell or solid organ transplants. Number of people suffering from, or suffering from lung conditions or severe viral respiratory infections. “

In this study, researchers isolated 218 samples of Aspergillus fumigatus from all over England, Wales, Scotland and Ireland between 2005 and 2017. Approximately 7 of the 10 samples are from infected individuals (153 samples from 143 patients in 5 hospitals) and the rest from the environment (65 samples) – from soil, compost, plant bulbs, air and other sources. Includes.

Researchers extracted DNA from the sample type and sequenced it to determine if there was a crossover in the environment or resistant spores found in some patients.

They found six strains of Aspergillus fumigatus in an environment that infected six patients. Researchers say genetic similarity indicates that the fungus has spread from the environment to the patient.

Dr. Joanna Rose, lead author of the Imperial MRC Global Disease Analysis Center within the Faculty of Public Health, said: We have identified how patients have acquired these infections-whether they develop in the lungs during treatment of the infection, or whether the mold spores that are infected first are drug resistant. Our studies have shown and confirmed that both transmission routes are possible and that resistant mold spores in the environment can invade and infect people’s lungs, causing difficult-to-treat diseases. There is a concern that there is sex. “

Of the 218 samples, nearly half (106 samples) were resistant to at least one of the primary azole drugs used in the clinic. Specifically, 48% (104 samples) were resistant to itraconazole, 29% (64 samples) were resistant to voriconazole, and 21% were resistant to posaconazole. Over 10% of the samples (26, including 23 environmental samples and 3 from patients) were resistant to 2 or more azole drugs.

In 218 samples, researchers discovered 50 new genes associated with drug resistance. A closer look at the DNA also revealed five new combinations (called single nucleotide polymorphisms or SNPs) of single-digit changes in DNA associated with drug resistance, including those that are resistant to multiple drugs.

Examining the genes in the Aspergillus fumigatus sample, researchers found that there were two different groups – Group A (123 of 218 samples) and Group B (95 samples). About 80% of the Group A samples were drug resistant, while about 85% of Group B were not drug resistant. Although the two groups were distinct, researchers found signs that they were exchanging genetic material and, in some cases, creating new versions of drug resistance.

Researchers say these findings indicate that the full range of Aspergillus fumigatus azole resistance is not yet understood.

Dr. Rhodes said: “Our findings highlight new ways of transmitting resistant infections to people and show that we need to better understand where and how Aspergillus fumigatus develops drug resistance. “