Kentucky Restaurant Outbreak
Health officials in Hopkins County, Kentucky, confirmed 24 cases of giardiasis in July 2025, significantly exceeding the county’s typical annual incidence of one to two cases. The Hopkins County Health Department traced the outbreak to El Tapatio restaurant in Madisonville, where state environmentalists identified temperature control issues in a walk-in refrigerator. The establishment ceased operations for thorough disinfection, food disposal, and staff retraining while cooperating with investigators. Public Health Director Denise Beach, speaking to local media, noted the investigation involved interviewing infected individuals about common exposures, including geographic proximity, shared recreational water venues, and dining locations.
National Outbreak Patterns
According to CDC surveillance, giardiasis causes over 1.1 million U.S. illnesses annually, with 14,887 cases formally reported in 2019. Incidence rates vary regionally, from 4.4 cases per 100,000 people in the South to 7.6 per 100,000 in the Northeast. New York City recorded the highest jurisdiction-specific rate (14.4 per 100,000), while Arizona reported the lowest (2.0 per 100,000). A 2021 CDC analysis of 111 outbreaks between 2012-2017 identified three primary transmission routes: water exposure (26% of outbreaks), person-to-person contact (25%), and food contamination (5%). Private residences and childcare facilities were the most frequent outbreak settings.
Minnesota Case Study
Minnesota exemplifies recurring transmission patterns, reporting 508 cases in 2018 alone. Childcare facilities accounted for five of seven state outbreaks that year, all involving person-to-person spread. Additional infections were linked to contaminated surface water on a Lake Superior hiking trail and a swimming beach. Notably, 48% of non-immigrant cases occurred between July and October, indicating seasonal peaks.
Symptoms and Prevention
Infected individuals typically develop symptoms, including watery diarrhea, abdominal cramps, nausea, and dehydration, 1-3 weeks after exposure. Asymptomatic carriers can still transmit the parasite. The CDC and local health departments emphasize prevention through handwashing with soap (particularly after diaper changes), avoiding water ingestion during swimming, and ensuring food workers with diarrhea abstain from duties for ≥24 hours after symptoms resolve.
Ongoing Monitoring
State health departments voluntarily report giardiasis outbreaks to the CDC’s National Outbreak Reporting System (NORS), supporting national tracking and response coordination.
