• Preamble
  • August is behind us but we are still sweltering in the hot and humid 'dogs days' so typical of that month. We should be writing about how to handle the heat, though it is a little late for that. Since there will be no September newsletter, we have some important reminders for you. Flu season will soon be upon us and we want all of you to be protected. Don't forget to wash your hands frequently! Have you heard why, in the middle of the SARS outbreak, Japan alone of all the Far East countries, was spared? It is speculated that it was frequent hand washing, for which the Japanese are noted, that spared them the ravages of this terrible virus. Remember that, and go and do likewise! Hand washing is one of your best protections against colds and other viruses. And for even more information, we are pleased to provide you with the following article.

  • Influenza, the Killer "Flu"
  • by Loren G. Miller, M.D., M.P.H.
    Assistant Professor of Medicine
    UCLA School of Medicine
    Division of Infectious Diseases
    Harbor-UCLA Medical Center
  • What is influenza?
  • Influenza is a virus that causes infections in humans as well as in a variety of birds and mammals. There are two main circulating types of influenza, influenza A and influenza B. Influenza A causes much more severe illness than influenza B.
  • Is influenza the same as "the flu"?
  • Influenza is the same thing as "the flu". Unfortunately, the word "flu" is commonly used colloquially for describing a variety of maladies such as colds (which are caused mainly by rhinoviruses, not influenza viruses) and the stomach "flu" (caused by viruses unrelated to influenza). Neither of these infections are technically "the flu". This broad use of the word "flu" is very unfortunate because it softens most people's perception of how serious influenza is. Colds and "stomach flus" are typically self-resolving infections that are mildly incapacitating, at worst. Influenza however, kills tens of thousands of Americans annually.
  • Influenza, the killer
  • Worldwide it is estimated that influenza kills 250,000 to 500,000 persons each year. These deaths occur primarily in elderly patients who live in industrialized countries. Because influenza is transmitted easily from person to person through sneezing and coughing, global spread of the virus during the winter occurs annually. Particularly bad outbreaks occurred in 1918 (the "Spanish flu"), which killed as many as 50 million persons worldwide. Other severe outbreaks occurred in 1957 ("Asian influenza") and 1968 ("Hong Kong influenza"). While many persons are currently concerned about SARS, only a relatively small number of persons worldwide have died of this infection, none in the United States. For most people, influenza poses far more of a serious threat to their health than SARS, at the present time.
  • Symptoms of influenza
  • Influenza infection is characterized by sudden onset of high fever (typically greater than 101.5(F), muscle and head aches, severe malaise, non-productive cough, sore throat, and runny nose. In other words, it is like a very bad cold with a high fever and severe aches. For those patients who have had it, the infection is usually very memorable for the significant amount of disability it causes, much more so than a cold. Although most people recover within 1-2 weeks without requiring any medical treatment, in the very young, the elderly and people suffering from medical conditions such as chronic lung disease, diabetes, cancer, or heart problems, influenza poses a serious risk. In these people, infection may lead to severe complications of underlying diseases, pneumonia, and death.
  • Influenza vaccines
  • Unfortunately, influenza is a master of change. Each year, the predominant influenza strain differs from the previous year. Each year scientists survey influenza activity worldwide to determine which influenza strains are most likely to circulate in the coming winter. Vaccines are then rapidly produced to prevent the likely invading strains. Most years the predominant circulating strain is successfully predicted. Influenza vaccine must be administered annually as each year's vaccine differs from the previous year's. Vaccines are given by injection, which typically become available in September or October. Persons who should be vaccinated annually include elderly persons, health care workers, and persons of any age who are considered at "high risk" for influenza-related complications due to underlying health conditions. This includes patients with chronic lung and heart disease. Recently, vaccination of children has been encouraged in the United States.
  • A new intranasal (nose spray) flu vaccine was approved in the United States in June 2003. It differs from the injection vaccine in that it uses a live virus rather than a killed virus. It should not be given to persons with poor immune function such as AIDS and cancer. It may also transiently exacerbate symptoms of asthma or reactive airway disease and should not be given to person with these conditions. Finally, both vaccines should not be given to persons with allergies to eggs or previous influenza vaccines.
  • "I had a flu shot before and it gave me the flu"
  • Physicians and nurses often hear this after offering a flu shot to a patient. This belief probably stems from many persons incomplete understanding of what the flu or influenza really is (again, it's not a cold). People typically get vaccinated during cold (and influenza) season and flu vaccines will not prevent colds. Several investigations have actually addressed this issue and found that persons getting flu shots were no more likely to get colds than persons administered a "dummy" (placebo) flu shot of saline (Nichol KL et al. Arch Intern Med 1996;156:1546 and Margolis KL et al. JAMA 1990;264:1139). Persons who got flu shots did have more soreness around the injection site than those given the placebo shots.
  • Antibiotics for the flu?
  • Commonly prescribed antibiotics do not work against the flu, however there are specific antiviral antibiotics that have activity against influenza virus. These antivirals include amantadine, rimantadine, oseltamavir, and zanamavir. All come in pill form except zanamavir, an inhaler antiviral that should not be administered to most persons with chronic lung disease. Antivirals modestly minimize or shorten the duration of influenza symptoms, but have to be given within 48 hours of symptom onset or they will have little to no effect on the infection. Some of these antivirals are also approved to prevent infection among persons who have been exposed to influenza but have not yet come down with symptoms.
  • Where can I get more information on the flu?
  • The World Health Organization: http://www.who.int/entity/csr/disease/influenza/en

  • Thank you Dr. Miller for this informative article! While many doctors' offices do not get their flu vaccine until October, it is a good idea to call now and make your appointment well in advance. Our thanks again to Dr. Miller for all of this valuable information!