New York City had more than half of the confirmed cases, 51, with Texas's 16 confirmed cases with one death and California's 14 confirmed cases a distant second and third, respectively.
The first confirmed U.S. fatality from swine flu was announced Wednesday. Health officials said a 23-month-old child who traveled to Texas from Mexico, died Monday from swine flu.
"The more recent illnesses and the reported death suggest a pattern of more severe illness associated with this virus may be emerging in the U.S.," the CDC said on its Web site. "Most people will not have immunity to this new virus and, as it continues to spread, more cases, more hospitalizations and more deaths are expected in the coming days and weeks."
President Barack Obama said in Washington public health officials have recommended schools with confirmed or suspected cases of swine flu should consider temporarily closing their facilities "to be as safe as possible."
A Chicago-area elementary school was closed Wednesday after a student contracted a suspected case of swine flu, the Chicago Sun-Times reported.
Chicago Public Schools Chief Executive Officer Ron Huberman said attendance rates at Kilmer Elementary School in Rogers Park had an higher-than-normal rate of absenteeism. School officials were investigating whether any of the students absent Tuesday may have contracted the virus.
Classes were canceled for a week at a San Jose, Calif., high school after a student tested positive for swine flu, the San Jose Mercury News reported.
Contra Costa County, Calif., health officials closed a Pittsburgh elementary school for a week beginning Wednesday, after tests indicated three probable cases.
A U.S. Marine based in Southern California's Twentynine Palms Marine Base has been tested to see if he has swine flu, the Pentagon said Wednesday.
The Marine and his roommate were quarantined on base while awaiting the results, CNN reported. Base officials said at least 35 Marines reportedly came in contact with the ill Marine, and all have been tested and given the antiviral Tamiflu.
California Gov. Arnold Schwarzenegger said his administration has "responded vigorously by deploying resources and preparing for the additional cases of swine flu that we are now seeing."
"We are already taking the steps that are appropriate for a Level 5 pandemic alert," Schwarzenegger said. "As our medical community has ramped up its monitoring of the virus, we expected to see more cases, and Californians should rest assured that we are prepared for this increase and also for the likelihood that we may see more severe cases."
The Ohio State University newspaper, The Lantern, reported an employee at the OSU Medical Center was diagnosed as a probable case.
Missouri Gov. Jay Nixon reported the virus appeared to have reached his state with initial tests indicating one Platte County resident likely has it.