California's Public Health Officer has ordered all of the state's healthcare providers to stop giving flu shots to healthy adults, according to press reports. Dr. Richard Joseph Jackson told reporters at a hastily convened press conference that the now-limited supply of flu vaccine must be given only to those whose lives may depend on it.

On Tuesday, the Centers for Disease Control announced that it had been notified by Chiron Corporation that none of its influenza vaccine would be available for distribution in the United States for the 2004-05 influenza season.

The Medicines and Healthcare products Regulatory Agency (MHRA) in the United Kingdom, where Chiron's Fluvirin vaccine is produced, had suspended the company's license to manufacture Fluvirin vaccine in its Liverpool facility for 3 months, the company told CDC, preventing any release of vaccine for the upcoming influenza season.

That development will reduce by approximately one half the expected supply of flu shots available in the United States for the 2004-2005 influenza season, according to the CDC.

Controversy has erupted over communications regarding the shortfall. British health officials said Friday that Chiron informed the U.S. Food and Drug Administration in mid-September of problems at a manufacturing site in England that could jeopardize the U.S. vaccine supply, according to press reports.

The supply of vaccine that is expected to be available in the United States this season is nearly 54 million doses, of which approximately 30 million doses already have been distributed by the manufacturer, Aventis Pasteur. Another 1.1 million doses of vaccine manufactured by MedImmnune will be available, says CDC.

Calling the situation "urgent," CDC has made interim recommendations for administering influenza vaccination during the 2004-2005 season. This guidance supersedes earlier advice.

Priority groups:

• all children aged 6-23 months;

• adults aged 65 years and older;

• persons aged 2-64 years with underlying chronic medical conditions;

• all women who will be pregnant during influenza season;

• residents of nursing homes and long-term care facilities;

• children 6 months-18 years of age on chronic aspirin therapy;

• health-care workers with direct patient care; and

• out-of-home caregivers and household contacts of children aged less than 6 months.

• Persons in priority groups identified above should be encouraged to search locally for vaccine if their regular healthcare provider does not have vaccine available.

• Intranasally administered, live, attenuated influenza vaccine, if available, should be encouraged for healthy persons who are aged 5–49 years and are not pregnant, including healthcare workers (except those who care for severely immunocompromised patients in special care units) and persons caring for children aged less than 6 months.

• Certain children aged less than 9 years require 2 doses of vaccine if they have not previously been vaccinated. All children at high risk for complications from influenza, including those aged 6–23 months, who present for vaccination, should be vaccinated with a first or second dose, depending on vaccination status. However, doses should not be held in reserve to ensure that 2 doses will be available. Instead, available vaccine should be used to vaccinate persons in priority groups on a first-come, first-serve basis.

• persons with a severe allergy (i.e., anaphylactic allergic reaction) to hens' eggs; and

• persons who previously had onset of Guillain-Barré syndrome during the 6 weeks after receiving influenza vaccine.

Persons who are not included in one of the priority groups above should be informed about the urgent vaccine supply situation and asked to forego or defer vaccination.

For more information, call the National Immunization Hotline at (800) 232-2522 (English), (800) 232-0233 (Español), or (800) 243-7889 (TTY).