Mexico's Caribbean coast is experiencing a significant influx of sargassum seaweed, leading to beach closures and raising health concerns among tourists and local authorities. The foul-smelling algae is engulfing popular resort areas, impacting tourism and prompting health officials to test local food and water.
The Mexican health ministry is investigating potential contamination in the resort region of Quintana Roo after British health authorities reported cases of cyclosporiasis, a parasitic illness causing stomach problems, in travelers who had visited the area. Laboratory results from tests on food and water at more than a dozen hotels are pending.
Mexico has recorded 33 cases of cyclosporiasis across several states. Environmental officials estimate that approximately 119,000 tonnes of sargassum are expected to wash ashore along Mexico's Caribbean coastline by the end of 2026. Beaches in the Riviera Maya, including Cancun, have been heavily affected, with reports indicating that by late June, 92.5 percent of registered beaches had an 'excessive' level of sargassum.
Workers have been deployed to remove the seaweed, a task that the state's governor, Mara Lezama, stated costs roughly 11 percent of the state's GDP. Warmer sea temperatures are contributing to the growth of sargassum, according to Brian Barnes, a research assistant professor at the University of South Florida's College of Marine Science. When stranded, the decomposing sargassum emits a strong odor.
In parallel, a notable increase in cyclosporiasis cases has been observed globally. At least 67 individuals in the UK have fallen ill with the infection since May, with more than half of those having returned from Mexico. Cyclosporiasis, caused by the parasite Cyclospora cayetanensis, is transmitted through contaminated food or water. Symptoms include diarrhea, loss of appetite, weight loss, stomach cramps, bloating, nausea, fatigue, and flu-like symptoms. While it does not naturally occur in the UK, 48 reported cases have been linked to travel to Mexico.
The Centers for Disease Control and Prevention (CDC) has reported nearly 7,000 cases of cyclosporiasis in the United States. Health officials are advising travelers to Mexico to take precautions against the parasitic infection.