The Centers for Disease Control (CDC) held a briefing this afternoon. Anne Schuchat, M.D., Interim Deputy Director for Science and Public Health Program and Daniel Jernigan, M.D., Ph.D., Medical Epidemiology, Influenza Division were the briefers.

There are 20 laboratory confirmed cases of the swine flu in the United States, from 5 states. 1 patient required hospitalization. All the patients have recovered. Human to human transmission has been confirmed. Patient ages range from 7 to 54.

All the US cases have recovered without antiviral treatment. High fever, sore throat, muscle aches, possible vomiting or diarrhea are the symptoms these patients experienced. The tested viruses are sensitive to Tamiflu and Relenza.

The interventions by the CDC and state and local governments will vary by locality. Listen to your state and local health departments for information for your area. It is important that individuals do some planning, such as what they will do if schools close.

We cannot stop this illness at the border. We cannot contain the virus. The goal is to slow transmission.

We need to prepare for the appearance of additional cases in additional states. Dr. Schuchat fears that we will see deaths in the United States from this illness.

The CDC has 12 samples from Mexico that are positive for swine flu. They also have samples that are positive for seasonal influenza. The illnesses are found in several parts of the country. CDC teams are in Mexico working with their public health authorities.

There is no vaccine for the swine flu at this time. The CDC is building a seed sample of the swine flu virus which would be given to vaccine manufacturers if the decision is made to create a vaccine. Growing the virus is the first challenge. There is new technology available that may speed that process.

The seasonal influenza vaccine component for human H1N1 initially appears to confer no immunity to the swine flu. One hypothesis is that exposure to human H1N1 may confer some immunity but there is not enough data at this time to prove or disprove this guess.

A great deal of science remains to be done. There is not enough data at this time to make very many conclusions. It is premature to suggest that the illness is different in Mexico or that it is affecting only specific age groups.

The normal disease screenings are being conducted at the border. The CDC plans to handout yellow cards to travelers giving signs and symptoms, and instructions to seek treatment if the person becomes ill. It will be up to the travelers to watch for illness and seek care.