Drug-resistant environmental mold: should we be concerned? – Advice Eating

Share on Pinterest
A species of fungus called Aspergillus fumigatus could become resistant to drugs. Collection Smith/Gado/Getty Images
  • An extremely common species of fungus found indoors and outdoors can damage the lungs of immunocompromised individuals.
  • These molds are becoming increasingly drug resistant, making infections difficult to treat.
  • Genetic analysis of a new study shows that the widespread presence of agricultural antifungal drugs in the environment is at the root of this growing drug resistance.

The mushroom Aspergillus fumigatus is everywhere. Mold is so common both indoors and outdoors that most people breathe in and out some of it on a daily basis with no ill effects.

However, in about 10 to 20 million people worldwide who have a compromised immune system, their spores remain in the lungs and as they progress aspergillosisthese spores can cause lung infections, allergic reactions and infections in other organs.

The preferred treatment for aspergillosis is administration of azole antifungal drugs. In recent years, however, the fungus has become increasingly resistant to these drugs.

A new study led by researchers at Imperial College London has found that azole antifungals, which remain in the environment from long-term agricultural use, could be the cause of drug resistance Aspergillus fumigatus.

dr Johanna Rhodes from Imperial, the lead author of the study, narrates Imperial College London News“Increasingly, cases of aspergillosis seen in the clinic are resistant to first-line azole drugs.”

“Understanding the environmental hotspots and genetic basis of evolving fungal resistance requires urgent attention as resistance impairs our ability to prevent and treat this disease,” notes lead author of the study, Professor Matthew Fisher.

“The prevalence of drug-resistant aspergillosis has increased from negligible levels before 1999 to up to 3-40% of cases across Europe today.”
– Prof. Matthew Fisher

The sense of urgency is heightened by a growing number of vulnerable people, especially since the pandemic.

“At the same time, more and more people could be susceptible to it Aspergillus fumigatus Infection due to the growing number of people receiving stem cell or organ transplants, undergoing immunosuppressive therapy, or suffering from pulmonary disease or severe respiratory viral infections,” adds Prof. Fisher. These respiratory infections include COVID-19.

The study is published in the journal natural microbiology.

are azole antifungals 14-alpha-demethylase Inhibitors. There are more than 25 different types of azoles that farmers have been using to protect crops from fungal diseases for decades.

dr Takahiro TakazonoAssistant professor at the University of Nagasaki in Japan, who was not involved in the study, said Medical news today:

“There are other classes of antifungal drugs for filamentous fungi… However, the route of administration of these antifungal drugs is intravenous only. are azoles [the] only oral antifungal to date.”

He also pointed out that there may be a new alternative to azoles that is currently undergoing clinical testing.

Researchers collected 218 Aspergillus fumigatus Isolates from 2005 to 2017 in England, Wales and Scotland. About 7 out of 10 molds, or 153 samples, came from 143 patients in five hospitals. The remaining 65 samples came directly from the environment.

Almost half, 48% or 104 samples were found to be resistant to itraconazole, the most commonly used azole antifungal.

Of the remaining drug-resistant samples, 64 or 29% were resistant to voriconazole and 21% were resistant to posaconazole, two other azole antifungals.

Over 10% or 23 environmental samples and 3 from patients were resistant to two or more azole drugs.

To establish possible links between the two sets of samples, the researchers extracted and sequenced DNA from the molds.

The genetic comparison of the samples revealed that six aspergillus Strains found in the environment had infected six patients.

The study describes their patient and environmental samples as “genetically very closely related.”

“The spurs of aspergillus floating all over the place,” said Dr. Takazono.

“[Aspergillus fumigatus spores] can be easily spread by the wind. Another possibility is that the spores (in the soil) can attach to agricultural produce and be spread in the daily life of an immunocompromised host.”
— dr Takahiro Takazono

“We weren’t sure how patients get these infections, whether they develop in the lungs while the infection is being treated, or whether the mold spores that infect them are drug-resistant in the first place,” says Dr. Rhodes.

“Our study finds that both routes of infection are possible and confirms concerns that pre-resistant mold spores in the environment can enter and infect people’s lungs, causing more difficult-to-treat diseases,” he adds.

According to the study, the results show that “patients at risk were infected by isolates that pre-acquired their resistance to azoles in the environment,” as research to date has not shown patients transmit their azoles Aspergillus fumigatus for the environment.

A new kind of resistance

Genetic analysis divided the samples into two distinct groups or “clades”. Clade A contained 123 isolates and Clade B 95. Approximately 80% of Clade A samples were drug resistant, while 87% of Clade B samples were not.

However, as separate as the two groups were, the researchers found evidence that they might exchange genetic material, allowing for novel drug-resistant genetic combinations.

“These results indicate the existence of new resistance mechanisms with an underlying substance polygenic basis and show this further understanding [of] the role of accessory genes in generating drug-resistant phenotypes is required,” the authors write.

Leave a Comment