Deadly Brain-Eating Amoeba Detected in 4 More of Mérida’s Artificial Lakes

Health authorities in Yucatán have ordered the closure of four more artificial lakes in Mérida after testing confirmed the presence of Naegleria microorganisms, more commonly referred to in the media as the “brain-eating amoeba.”

Testing again returned positive for the artificial lake at La Isla, as well as another smaller body of water nearby in Cabo Norte.  The amoeba was also detected at Parque Ecologico de Oriente and in the artificial lakes at both El Centenario Zoo and La Plancha.

Health Services of Yucatán announced the laboratory findings after a comprehensive evaluation of nine urban water features across the city; the rest tested negative for the deadly amoeba.  

Physical barriers and warning signs are being installed immediately to prevent public access to the affected waters while municipal, federal, and private operators begin chemical sanitation protocols.

The newly restricted sites include water features in some of the metropolitan area’s most heavily visited public and private spaces. 

Public Access and Park Operations

State and municipal officials emphasized that detecting the amoeba in these water bodies does not require closing the surrounding facilities. All affected public parks and zoological grounds remain fully open to visitors and families. 

Administrative guidelines clarify that none of the nine inspected sites are designed or approved for swimming or recreational bathing, as they function strictly as ornamental urban features. At sites like Animaya, boat tours continue because visitors have no direct contact with the water.

Origin of the Municipal Water Inspection

The citywide testing drive was triggered by a fatal medical emergency that occurred at an artificial lake at Plaza La Isla. Within the lake, a water sports instructor contracted a rare brain infection after instructing water sports, mainly wakeboarding, in the contaminated water. 

Medical surveillance teams monitored hundreds of individuals who had potential exposure in the weeks following the incident. Health authorities confirmed that all monitored individuals completed their required observation periods without symptoms, indicating no other human cases have occurred.

Scientific Remediation and Health Protocols

Clearing the restricted lakes is scheduled to take place by health authorities and independent research institutions. Operators at each location are carrying out remediation measures under direct technical guidance from specialists at the Autonomous University of Yucatán and the Center for Research and Advanced Studies. 

Health officials reiterated that the Naegleria amoeba is transmitted only when contaminated water is forced high into the nasal cavity, and it cannot be contracted through casual contact, surface splashes, or drinking tap water.

Authorities have reiterated that the amoeba does not threaten people engaged in everyday or leisure activities. Nevertheless, a growing number of social media posters have taken it upon themselves to exaggerate the risks and spread conspiracy theories. 

For example, a user who goes by Xochitl on Facebook claimed that the amoeba had been planted by members of the government opposition to make Yucatán’s governor look bad. On Reddit, a group of posters argues that no water sources are safe, and that the only way to protect oneself from the amoeba is to turn off one’s access to the public water supply.

Others question the wisdom of building large artificial water features in Yucatán, given that they are for the most part stagnant and that during the hottest months, it is logical that they would become a “cauldron” for dangerous amoebas. 

Restricted lakes will remain cordoned off until thorough chemical treatment is complete and follow-up testing verifies that safety standards have been met.