Dr. William Kumprey, an emergency medicine physician and associate chief medical officer for ThedaCare, is warning Northeast Wisconsin residents affected by April 2026 flooding that mold can develop in water-damaged homes within two to three days — with respiratory symptoms potentially appearing days, weeks, or even months after exposure begins.
Kumprey advises that homeowners can self-remediate small mold areas under 10 square feet within 24-48 hours, but larger affected areas involving carpeting and drywall require professional remediation. He cautioned that continued exposure in enclosed environments compounds health risks including respiratory illness and asthma.