NEW YORK -- The tally of confirmed swine flu cases in the United States jumped Sunday to 245 in 35 states, but officials said that increase is largely from catching up on a backlog of lab tests rather than a sudden spurt in new infections.
The new count reflects streamlining in federal procedures and the results of tests by states, which only recently have begun confirming cases, said Dr. Anne Schuchat of the Centers for Disease Control and Prevention in Atlanta.
Because states are now contributing their results and because there are many cases to analyze, "I expect the numbers to jump quite a bit in the next couple days," she said.
Beyond eating into the backlog, the new number also reflects that "we do think this virus is fairly widespread," she said.
"Virtually all of the United States probably has this virus circulating now," she said. "That doesn't mean that everybody's infected, but within the communities, the virus has arrived."
Early Sunday, the CDC updated its number to 226 cases in 30 states, up from 160 in 21 states. Later, five more states reported confirmed cases, and new illnesses elsewhere were added to the tally.
Mexico's health secretary said Sunday that his country's outbreak is "now in its declining phase," but Schuchat said that the United States got off to a later start. "We believe we are just in the upswing here," she said.
Scientists are still gathering information on how severe the nation's 30 hospitalized cases are, she said. They are mostly older children and young adults, in contrast to ordinary flu, which tends to send the elderly and very young to the hospital, Schuchat said.
Local authorities announced more school closings Sunday. Officials in New Mexico said 14 schools in four towns were being closed for at least a week after the state's first swine flu case was confirmed, and the New Mexico Activities Association suspended all athletic and activity programs at member schools across the state.
In Arizona, all 10 public schools in the border city of Nogales canceled classes this week after a student tested positive for swine flu.
California officials suspended all visitations at prisons pending results of tests on an ill inmate at Centinela State Prison.