New U.S. swine flu cases spread pandemic fears

As Mexico hunkers down, 2 cases found in Kansas and 8 likely in NYC

Worries that the new swine flu strain that has killed as many as 68 people and sickened more than 1,000 across Mexico has “pandemic potential” increased with the announcement that the virus has spread to Kansas and likely to New York City.

On Saturday, two new cases were confirmed in Kansas — the first U.S. cases outside of California or Texas. An additional case was confirmed in California. And New York City Health Commissioner Dr. Thomas Frieden said tests showed that eight New York high schoolers had a type A influenza virus that was "probable" swine flu.

Samples have been sent to the U.S. Centers for Disease Control and Prevention for further testing to see if they are indeed the unusual H1N1 strain of swine flu; results are expected Sunday. The students showed only mild flu symptoms and are feeling better.

What is concerning about this is that it is likely swine flu and second that it is spreading person to person," Frieden said. He added, "We have seen no increase citywide in flu-like cases."

About 100 students at the private St. Francis Preparatory School in the New York City borough of Queens became sick last week, prompting the tests.

The Kansas cases involved two adults living in the same house; one is still ill and the other is recovering. One of the patients recently traveled to Mexico, flying in and out of Wichita.

NBC News has also learned there are suspected cases in Minnesota and Massachusetts. The total number of U.S. cases stands at 11 confirmed so far.

'Be prepared for uncertainty'
It may be too late to contain the sudden outbreak, warned the CDC, which has stepped up surveillance across the United States. "We are worried," said the CDC's Dr. Anne Schuchat.

“We don’t think we can contain the spread of this virus,” said Schuchat, Interim Deputy Director for Science and Public Health Program. “We are likely to find it in many other places.”

Because cases are spreading in the U.S. and in several sites in Mexico, officials now must work to detect infections and reduce their severity, if possible.