Cats and Humans: A Fungus That Might Reach the U. S.

A new fungal threat is circling the globe, and experts say it could soon appear in America. The culprit, Sporothrix brasiliensis, first showed up in Brazil in the 1990s and has since spread to several South American countries. Thousands of cats and over eleven thousand people have already fallen ill in those regions.

Symptoms

• Cats: painful skin ulcers and swollen lymph nodes.
  Untreated, the infection can spread throughout the body and even prove fatal.

• Humans: a scratch or bite from an infected cat can trigger similar lesions.
  People with weakened immune systems face the highest risk of severe outcomes.

Why It’s Worrisome

Unlike many fungal infections that come from the environment, this one can travel in its yeast form. Cats may spread it through:

• Bites
• Scratches
• Grooming
• Sneezing out mucus that carries the fungus

The organism can survive on surfaces for weeks, so a single infected animal could contaminate an entire household.

Cross‑Border Spread

A family that relocated from Brazil to the United Kingdom developed infections years later after unknowingly bringing an infected cat with them. Even a veterinarian who treated the animal became ill, showing how quickly the fungus can jump from pet to person.

Testing and Prevention

There is no commercial test available for Sporothrix brasiliensis. When cats enter the United States, authorities typically require only a basic health certificate that notes obvious illness, not a detailed laboratory confirmation. This gap means an infected animal could slip through unnoticed.

Health officials are monitoring its movements closely. While it has not yet been detected in the United States, experts warn that once it arrives, the spread could be rapid and difficult to control.

Takeaway

Pet owners should stay vigilant:

• Seek veterinary care promptly if their cat shows signs of infection.
• Keep an eye on travel advisories that may affect animal health.