That appears to be what happened in Severna Park. Previously the virus there was linked to one family, that of a federal agent who served on the president's advance team when Barack Obama went to Mexico last month. Three members of the agent's family - his wife, son and a nephew - were sickened. The grandmother of the sick student also appears to be infected.
The second Folger McKinsey student appears to have picked up the virus from his classmate. All are expected to recover.
The idea behind closing the schools - which some have argued is too drastic a measure - is to keep social distance while the disease is contagious and to slow its march. Hundreds of schools across the country have been closed, and the CDC says they may remain shut for up to 14 days.
"Schools and children are very common reservoirs for infectious diseases, including infectious viruses like influenza," Schuchat said. "They tend to have lots of social contacts, more than adults."
That is why officials have suggested that students in affected schools - which also include Milford Mill Academy in Baltimore County, Rockville High School in Montgomery County and Montpelier Elementary School in Prince George's County - not congregate at malls, the movies, parties or any other gathering spot.
Folger McKinsey's 5K Run and 1 Mile Fun Run/Walk, a fundraiser scheduled for Sunday, was postponed upon the advice of the Anne Arundel County Health Department.
But Saturday morning was like most other spring Saturdays in Severna Park. Kinder Farm Park was packed with kids playing baseball. Some of the kids attend Folger McKinsey; others go to Shipley's Choice Elementary School nearby. Nearly all of them shook hands at the ends of their games.
