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Press Release

For Immediate Release: October 8, 1999
Contact: CDC Media Relations (404) 639-3286

Flu Season 1999-2000: Vaccine Information

  • Influenza viruses ("the flu) infect the respiratory tract. Symptoms include fever, cough, sore throat, runny or stuffy nose, headache, muscle aches, and extreme fatigue. Although nausea, vomiting, and diarrhea sometimes occur during an infection, these symptoms are rarely prominent. "Stomach flu" is a misnomer sometimes used to describe gastrointestinal illnesses that are actually caused by other organisms.
  • Influenza viruses continually change over time, and each year the vaccine is updated to include the viruses that are most likely to circulate in the upcoming influenza season. The influenza vaccine (flu shot) that has been produced for the 1999-2000 flue season contains three influenza virus strains designated A/Beijing/262/95-like (H1N1), A/Sydney/5/97-like (H3N2), and B/Yamanashi/166/98 hemagglutinin antigens.
  • The best time to get a shot is from October through mid-November. However, shots can be taken at any time during the season. It takes 1-2 weeks, after receiving the shot, for a person to develop protective antibody.
  • Flu vaccines are 70%-90% effective in preventing influenza among healthy adults. Among elderly or people with chronic conditions, the vaccine may be less effective in preventing disease than in preventing serious complications and death.
  • Annual flu shots are recommended for persons who are at high-risk for serious complications, if they should get influenza. Groups at increased risk include:
    • Persons 65 years of age and older;
    • Residents of nursing homes and chronic care facilities;
    • Adults and children (6 months of age and older) who have chronic disorders of the pulmonary or cardiovascular systems, including children with asthma;
    • Adults and children who have required regular medical follow-up or hospitalization during the preceding year because of chronic metabolic diseases (including diabetes), renal dysfunction, hemoglobinopathies, or immunosuppression;
    • Children and teenagers who are receiving long-term aspirin therapy and, therefore, are at increased risk for developing Reye syndrome after an influenza infection;
    • Women who will be in the second or third trimester of pregnancy during the flu season.
  • Persons who care for and/or live with people at high risk for complications from flu should also get a shot. These persons include:
    • Physicians, nurses, and other personnel in both hospital and outpatient-care settings;
    • Employees of nursing homes and chronic-care facilities who have contact with patients or residents;
    • Providers of home care to persons at high risk (e.g., visiting nurses and volunteer workers);
    • Household members (including children) of persons in high-risk group.
  • In the United States, flu season usually peaks in late December and early March.
  • Surveillance information is updated weekly from October through May, and is available online at Or, you can receive the information by fax by calling toll-free (888) 232-3238 (document no. 361100).

Flu Season 1999-2000: See also...

  • Secretary Shalala Urges Older Americans to get 1999 flu shot
  • Is there a new flu virus circulating this season?
    Has flu season come early in the United States?
  • Persons with Chronic Conditions
  • Information for Travelers
  • Flu Pandemics


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    Atlanta, GA 30333
  • 800-CDC-INFO
    TTY: (888) 232-6348
  • Contact CDC–INFO The U.S. Government's Official Web PortalDepartment of Health and Human Services
Centers for Disease Control and Prevention   1600 Clifton Road Atlanta, GA 30329-4027, USA
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