Key Takeaways
- CDC guidance places Legionella prevention responsibility directly on vacation rental operators.
- Nearly 1 in 7 Legionnaires’ disease patients reported staying at hotels or vacation rentals.
- Low STR occupancy reduces water flow, creating ideal conditions for Legionella growth.
Nearly 1 in 7 Legionnaires’ disease patients reported staying overnight at hotels, private homes, or vacation rental properties, and the CDC is now looking directly at short-term rental operators to help close the gap.
According to a news release from EMSL Analytical, the testing firm is urging vacation rental owners and property managers to comply with CDC guidance designed to help reduce Legionella risks in building water systems.
“Short-term rental properties can experience periods of low occupancy that lead to stagnant water in plumbing systems,” said Jason Dobranic, Ph.D., Vice President of Microbiology and Life Sciences at EMSL Analytical, Inc.
“Testing for Legionella and implementing sound water management practices can help property owners identify risks early and take steps to protect guests, staff, and their business reputation.”
Legionnaires’ disease kills roughly 1 in 10 people who contract it, and U.S. case counts have been rising.
About half of Legionnaires’ disease patients who reported travel and staying at a vacation rental property also reported hot tub use.
What the CDC Legionella guidance means for STR operators
The CDC’s guidance targets three core risk zones in short-term rentals, which are hot water systems, hot tubs, and plumbing.
Potential exposure sources in vacation rentals include hot tubs, faucets, showerheads, and decorative fountains, particularly where warm temperatures, stagnant water, and low disinfectant levels allow Legionella to grow.
Operators are directed to keep water heaters at or above 120°F, flush heaters routinely, and maintain disinfectant levels in hot tubs even during periods of low or no occupancy.
Low and irregular occupancy, a defining feature of the short-term rental model, decreases water flow and can drop disinfectant levels to ranges where Legionella thrives.
The CDC also advises flushing faucets and showerheads before guest arrivals if they have sat unused for a week or more.
Related: The smart thermostats STR hosts should actually buy in 2026
EMSL Analytical, which offers both rapid PCR and traditional culture methods for Legionella testing of environmental samples, frames compliance as both a public health obligation and a liability shield.
Outbreaks tied to a single property can trigger public health investigations and significant reputational damage.
Multi-unit buildings with centralized hot water systems face an additional requirement — a formal Legionella water management program.
With summer occupancy approaching peak season and STR demand surging across coastal and resort markets, operators who have not yet audited their water systems are running out of runway before their highest-risk booking window opens.
For more information about EMSL’s Legionella testing services and sampling supplies, visit www.LegionellaTesting.com, email info@EMSL.com, or call (800) 220-3675. You can also visit the CDC for additional guidance.
