Mold is usually a background nuisance. But a new review of four Atlanta-area hospitals found 449 invasive mold disease cases over five years, with nearly one-third of patients dying in the hospital — putting a grim number on an infection doctors say can be difficult to recognize.
The report examined laboratory and medical records from 2020 through 2024, identifying 968 potential cases before classifying 449 as invasive mold disease. The study recorded a 30% in-hospital death rate, while 90-day mortality reached 45% among cases with sufficient follow-up data, according to the CDC study. Hospitals saw roughly three to five cases per year for every 100 inpatient beds.
That does not mean every musty basement is a medical emergency. Most people inhale mold spores without becoming seriously ill, but invasive infections can develop in people with weakened immune systems and can affect the lungs, sinuses, skin, brain or multiple organs, the U.S. Centers for Disease Control and Prevention says.
Why These Infections Can Slip Through The Cracks
Invasive mold disease is not a nationally notifiable condition, meaning doctors are not required to report every case to the federal government. The study also found that 35% of patients did not have the classic host factors typically associated with these infections, suggesting that surveillance based only on familiar risk profiles could miss cases, according to the Associated Press and the CDC researchers.
Jeremy Gold, one of the CDC researchers, told FOX 5 DC that the findings provide an estimate researchers have not previously had at the local level. Earlier CDC work estimated that invasive mold disease could be connected to more than 15,000 U.S. hospitalizations each year, although the new Atlanta data are not designed to represent every region of the country.
Atlanta Data Point To A Larger Public Health Question
The Atlanta study found Aspergillus was the most commonly identified mold, and pulmonary infections accounted for most cases. Patients with a current or recent COVID-19 diagnosis faced especially severe outcomes: 66% died within 90 days, compared with 41% of patients without recent COVID-19, according to the CDC report.
Researchers warned that a growing population of older and medically vulnerable patients, along with climate-related flooding and other environmental changes, could increase the burden of serious mold infections. The study also gives hospitals a baseline for distinguishing expected case levels from a possible health care-associated outbreak — a decidedly unglamorous but important use for better counting.
What People At Higher Risk Should Know
People undergoing cancer treatment, taking immune-suppressing drugs, or living with a transplant or other immune-compromising condition should avoid entering buildings with visible or known mold and should not take part in cleanup, the CDC says. After flooding, homes and buildings should be dried within 24 to 48 hours when possible, while mold removal is handled by someone who is not at elevated risk or by a qualified professional, according to the agency's guidance.
