The cases of the A/H1N1 flu in the United States have increased to 1,639 in 43 states, the U.S. Centers for Disease Control and Prevention (CDC) said on Friday.

The update registered a sharp increase from the case count on Thursday when confirmed cases were 896.

The CDC said that because there is a backlog of likely cases that need to be confirmed through extra testing, the number of cases may jump quickly day to day as more suspected cases are confirmed.

According to the CDC, the state of Illinois has 392 confirmed cases of the H1N1 flu, followed by 240 of Wisconsin, 174 of New York, 131 of Arizona and 107 of California.

On Tuesday, the Texas Department of State Health Services said that a woman, who died earlier this week, has been the first death of a United States resident with the H1N1 flu.

On April 29, the CDC said a 23-month old toddler in Texas became the first fatality from H1N1 flu in the United States. The child is a Mexican who traveled to Texas for medical treatment. He is also the first person to die of H1N1 flu outside of Mexico.

CDC officials have said they expect the H1N1 flu to spread to all 50 states, to cause severe disease and some deaths.

(Xinhua News Agency May 9, 2009)