A four-year-old in Jerusalem was diagnosed with polio, marking the first known case in Israel since 1989, according to the country’s health ministry. The boy was not vaccinated against the disease, according to the ministry’s Sunday statement. It was unclear what symptoms he might have been experiencing, but authorities said he had not yet been hospitalized, according to Haaretz. A regional health administration in the city has opened an epidemiological investigation to keep tabs on the child’s health. Polio, a highly infectious virus that can be life-threatening, has no cure, but is easily prevented through vaccination. It has been eradicated in many regions, but remains endemic in places like Afghanistan, Nigeria, and Pakistan.