The latest weekly update issued on June 13 from the Centers for Disease Control and Prevention indicates a total of 13,217 confirmed or suspected cases and 27 deaths attributed to the H1N1 flu virus.

During week 23 (June 7-13), influenza activity decreased in the United States, however, there were still higher levels of influenza-like illness than is normal for this time of year.

·Two thousand seven hundred sixty-five (38.7 percent) specimens tested by U.S. World Health Organization and National Respiratory and Enteric Virus Surveillance System collaborating laboratories and reported to CDC/Influenza Division were positive for influenza.

·Over 98 percent of all subtyped influenza A viruses being reported to CDC were pandemic influenza H1N1 viruses.

·The proportion of deaths attributed to pneumonia and influenza was slightly above the epidemic threshold.

·One influenza-associated pediatric death was reported and was associated with pandemic influenza A, H1N1 virus infection.

·The proportion of outpatient visits for influenza-like illness was below the national baseline. One of the 10 surveillance regions reported ILI above their region-specific baseline.

·Eleven states reported geographically widespread influenza activity, six states and Puerto Rico reported regional influenza activity, the District of Columbia and 13 states reported local influenza activity, and 20 states reported sporadic influenza activity.

Novel influenza A is a new flu virus of swine origin that was first detected in Mexico and the United States in March and April.. The first novel H1N1 patient in the United States was confirmed by laboratory testing at CDC on April 15. The second patient was confirmed on April 17. It was quickly determined that the virus was spreading from person-to-person. On April 22, CDC activated its Emergency Operations Center to better coordinate the public health response. On April 26, a public health emergency was declared.

It's thought that the H1N1 flu spreads in the same way that regular seasonal influenza viruses spread; mainly through the coughs and sneezes of people who are sick with the virus.

It's uncertain at this time how serious or severe this novel H1N1 virus will be in terms of how many people infected will develop serious complications or die or how this new virus may affect the United States during its upcoming influenza season in the fall and winter. Because this is a new virus, most people will have little or no immunity against it, and illness may be more severe and widespread as a result. In addition, currently there is no vaccine to protect against this novel H1N1 virus. CDC anticipates that there will be more cases, more hospitalizations and more deaths associated with this new virus.

At this time, most people who have become ill with novel H1N1 in the United States have recovered without requiring medical treatment and have experienced typical flu symptoms.