More than 200 people in 27 states are being monitored for possible exposure to monkeypox after they had contact with an individual who contracted the disease in Nigeria before traveling to the United States this month, according to the Centers for Disease Control and Prevention. To date, no additional cases have been detected. State and local health authorities are working with the CDC to identify and assess the individuals, and follow up with them daily until late this month, said Andrea McCollum, who leads the poxvirus epidemiology unit at the agency’s National Center for Emerging and Zoonotic Infectious Diseases. “It...