Cosa c'è da sapere sulla ciclosporosi, l'epidemia di malattie gastrointestinali che colpisce gli Stati Uniti

A gastrointestinal illness outbreak linked to the parasite Cyclospora cayetanensis has affected over 800 individuals in the United States, according to the Centers for Disease Control and Prevention (CDC). The outbreak, which spans 31 states, has prompted health officials to investigate potential food sources responsible for the infections. While the U.S. has seen a surge in cases, Canadian authorities have not reported similar levels of illness, though experts warn that the risk of the parasite spreading north remains. In the U.S., the CDC has confirmed 843 cases of cyclosporiasis, with additional reports of more than 1,500 possible cases under investigation. State-level data reveals a more severe situation, particularly in Michigan, which has recorded 3,309 cases as of recent reports. Of those, 44 individuals have required hospitalization. No fatalities have been reported thus far. The national figures lag behind state-level statistics, making it difficult to fully grasp the current scope of the outbreak. Cyclosporiasis is caused by a microscopic parasite that is not visible to the naked eye. It primarily affects the digestive system, leading to symptoms such as frequent, watery, and sometimes explosive diarrhea. Other common signs include nausea, abdominal cramps, loss of appetite, weight loss, and fatigue. The incubation period ranges from two to 14 days following exposure to the parasite. Diagnosis typically involves laboratory tests on stool samples, as the parasite is not easily detectable through routine screening methods. Transmission of the parasite occurs mainly through ingestion of contaminated food or water. Unlike many infectious diseases, cyclosporiasis is not typically transmitted from person to person. Instead, it spreads through consumption of food or water that has been tainted by feces containing the parasite. This mode of transmission is more prevalent in regions with less developed sanitation infrastructure, where human waste can contaminate crops and water supplies. Infections in North America are often linked to imported foods, especially fresh produce. In past outbreaks in Canada, including one in 2017 that saw 164 cases across four provinces, the source of contamination remained unidentified. However, public health officials have noted that such outbreaks are frequently associated with imported fresh produce. The Public Health Agency of Canada stated recently that it is not currently investigating any active cyclosporiasis outbreaks within the country. Nevertheless, health professionals remain vigilant, given the proximity of the U.S. outbreak and the potential for cross-border transmission. Experts suggest that the current U.S. outbreak likely stems from a specific food source that became contaminated outside the country. Given the global trade of agricultural products, it is plausible that the parasite entered the U.S. food chain through imports from countries where cyclosporiasis is more common, such as parts of Latin America, Africa, and South Asia. These regions often experience higher rates of infection due to inadequate sanitation practices that allow human waste to contaminate crops and water sources. Dr. Susy Hota, medical director for infection prevention and control at the University Health Network in Toronto, emphasized that while the risk of cyclosporiasis spreading to Canada exists, the likelihood of a major outbreak remains low. She noted that the U.S. has robust sanitation systems, which generally prevent such parasites from entering the local food supply. However, she cautioned that the possibility of contaminated food being distributed widely could lead to sporadic cases in Canada, especially among individuals who consume imported produce. Health officials continue to monitor the situation closely, urging consumers to wash all fresh fruits and vegetables thoroughly before consumption. They also recommend avoiding consumption of raw or undercooked food, particularly from sources known to carry the parasite. As investigations into the origin of the U.S. outbreak continue, public health agencies are working to identify the contaminated product and implement measures to prevent further spread.