Information on Influenza from the National Institutes of Health
Influenza (flu) describes a family of viruses that cause a variety of symptoms ranging from mild to severe. In 2009, there are two types of flu circulating in the United States: seasonal flu and H1N1 (Swine flu). A third type of flu, Avian or Bird (H5N1), is being monitored overseas. During most flu seasons, 5-20% of Americans contract the flu and approximately 36,000 people die from flu or its complications. Since very few individuals have immunity to the current H1N1 virus, experts expect this flu season may be more severe than usual. Read more at www.flu.gov.
Information on Influenza from the Center for Disease Control
Extensive information influenza at the U.S. Center for Disease Control.
Information on Influenza from the National Foundation for Infectious Diseases
Influenza, more commonly referred to as "the flu," is a highly contagious viral infection of the nose, throat and lungs. Influenza occurs most often in the late fall, winter and early spring. It is a serious infection which afflicts more than 60 million Americans every year. Influenza impacts people of all ages. Common symptoms include a high fever (101ºF-102ºF) that begins suddenly, sore throat, chills, cough, headache and muscle aches. ..Read more at the National Foundation for Infectious Diseases.
Flu: Essentials at Consumer Reports
What is it? What are the symptoms? How common is it? What will happen? Key points about treatments at Consumer Reports.
Human Swine Flu (H1N1) and Novel Influenza Pandemics
On May 28, 2009, shortly before the WHO's declaration, the New York Academy of Sciences brought together a panel of vaccine experts, epidemiologists, and policymakers to discuss the outbreak. The purpose of the symposium was to share current data and insights into human swine flu, as well as strategies that could help quell the impact of future pandemic strains or a more virulent form of H1N1. See their meeting report, podcasts, videos and more at New York Academy of Science website.
The Cochrane Reviews have summarized data about the benefits and harms of several interventions for preventing and treating influenza. These comprehensive reviews provide valuable information for patients, doctors, and healthcare decision-makers about what steps to take or interventions to use to prevent influenza or aid its treatment. More at the Cochrane Collaboration.
Interactive Quiz: Do I have H1N1 flu?
Are you or a loved one worried you might have the H1N1 flu? Take this H1N1 Flu self-evaluation provided by flu.gov.
Podcast: Summary of Cochrane Reviews on influenza
Although there is a lack of research into interventions to prevent and treat influenza in a pandemic, there are several trials and a number of Cochrane Reviews of interventions for seasonal flu which might be relevant at this time. We asked Tom Jefferson, a researcher based in Italy, who has worked on many of these Cochrane Reviews, to summarize his conclusions.
Podcast: Beneficial effects of physical interventions
Across the collection of Cochrane Reviews for preventing and treating influenza, the most effective interventions appear to be ways to prevent the spread of the virus. Tom Jefferson, the lead author of this Review, explains their findings.
Podcast: Vaccinating Children Against Influenza
Children over 6 months in age should be vaccinated each year against influenza. Young children, in particular, are at increased risk of developing serious complications from the flu. The annual vaccines are safe and effective. Listen to the podcast from the Center for Disease Control.
Video: Personal Stories of Families Touched by Influenza
Many parents feel that flu is not a serious illness and decide not to vaccinate their children. However, when young children contract the flu, the disease may progress quickly or they may develop serious, life-threatening conditions. Listen to the personal stories of families that learned firsthand how severe influenza infections can be in children in a video from the CDC.
Podcast: Preventing the Spread of the Flu
Avoiding contact with infected persons and receiving annual flu vaccinations are the most effective ways to prevent contracting the flu. Two vaccines are required this year: the seasonal flu vaccine and the H1N1 pandemic flu vaccine. In addition, people should remember to practice good hygiene such as washing their hands frequently, avoid touching their faces, and coughing or sneezing into their elbow. Lastly, when public announcements are made to avoid crowds or a particular location, people should follow the instructions. Listen to the podcast from the CDC.
Managing Seasonal Influenza
When flu-like symptoms are experienced, individuals at high risk of developing influenza-related complications should be tested for the presence of flu virus. For the most accurate testing, samples from the nose, throat, or blood should be tested for the presence of influenza virus within 5 days of symptom onset. Medications to reduce the replication of the virus should be used only in patients at high risk for developing complications. View the major recommendations at the National Guideline Clearinghouse.
Priority of H1N1 Vaccination Administration
Prevention of Influenza
The best way to prevent influenza is to receive an annual vaccination. The nasal vaccine, which contains weakened, live viruses, can be administered to individuals ages 2-49. Individuals not within this ages 6 months to 2 years or older than 49 years should take the injectable vaccine, which contains killed flu viruses. Individuals ages 2-49 may choose between either the nasal or injectable vaccine. Children under the age of 8 should receive 2 doses, 1 month apart, the first year they take a flu vaccine. While it is recommended that everyone takes a flu vaccine, it is critical for individuals at high risk of flu-related complications or in contact with high risk individuals to receive the annual flu vaccine each year. View the major recommendations at the National Guideline Clearinghouse.
Pregnancy and H1N1 Influenza
The symptoms of swine flu (H1N1) are similar in pregnant women and nonpregnant individuals. However, pregnant women are at increased risk of serious complications, such as bacterial pneumonia. In addition, high fever during the first trimester of pregnancy may increase the risk of neural tube defects in the fetus. Pregnant women are able to take antiviral medications to reduce the severity of illness and vaccines to reduce the severity of illness. View the major recommendations at the National Guideline Clearinghouse.
Containing Suspected Avian Influenza Cases
Patients exhibiting symptoms of influenza should be interviewed about recent travel destinations. If the history indicates high risk for exposure to avian influenza (H5N1), health care workers should use extreme caution when interacting with the patient. H5N1 is a dangerous form of influenza, so care should be taken to produce the exposure of health care workers and other patients to the infected individual. Laboratory tests can confirm if the person is infected H5N1 or another virus. View the major recommendations at the National Guideline Clearinghouse.
Antiviral Medications in the Treatment of Influenza
Antiviral medications, such as oseltamivir or zanamivir, are recommended for the treatment of influenza. These drugs should be offered to individuals at high risk of influenza side effects, such as immunocompromised patients, asthmatics, diabetics, and people with heart or kidney disease. In addition, antiviral treatment should be offered to people who did not receive the seasonal flu vaccine or who received a vaccine that was poorly matched to the strains circulating in the current year. Oseltamivir and zanamivir are most effective when given within 48 hours of symptoms beginning. View the major recommendations at the National Guideline Clearinghouse.
Free Full Text: Cross-Reactive Antibody Responses to the 2009 Pandemic H1N1 Influenza Virus.
A new pandemic influenza A (H1N1) virus has emerged, causing illness globally, primarily in younger age groups. To assess the level of preexisting immunity in humans and to evaluate seasonal vaccine strategies, we measured the antibody response to the pandemic virus resulting from previous influenza infection or vaccination in different age groups. Free full text available at Pubmed.
Abstract: H1N1 2009 influenza virus infection during pregnancy in the USA.
Pandemic H1N1 2009 influenza virus has been identified as the cause of a widespread outbreak of febrile respiratory infection in the USA and worldwide. We summarised cases of infection with pandemic H1N1 virus in pregnant women identified in the USA during the first month of the present outbreak, and deaths associated with this virus during the first 2 months of the outbreak. Abstract available at Pubmed.
Abstract: Avian influenza: a review.
PURPOSE: A review of the avian influenza A/H5N1 virus, including human cases, viral transmission, clinical features, vaccines and antivirals, surveillance plans, infection control, and emergency response plans, is presented. Abstract available at Pubmed.
Free Full Text: Pandemic and seasonal flu: what you need to know.
This coming flu season will be interesting—and confusing. As of August 6, 2009, the Centers for Disease Control and Prevention (CDC) reported 6506 hospitalized cases and 436 deaths from the pandemic H1N1 flu virus since the first US cases were reported in April 2009. Free full text available at Pubmed.
Abstract: Understanding influenza transmission, immunity and pandemic threats.
The current pandemic threat can be best understood within an ecological framework that takes account of the history of past pandemics caused by influenza A, the relationships between pandemic and seasonal spread of influenza viruses, and the importance of immunity and behavioural responses in human populations. Abstract available at Pubmed.
Free Full Text: Seasonal influenza vaccines: evolutions and future trends.
Influenza vaccines are among the oldest still in active use. Purity, potency and standardization have been improved over the years. However, they are still produced using the same basic methods as when they were first introduced. Free full text available at Pubmed.
Free Full Text: Pandemic and Seasonal Influenza: Therapeutic Challenges
Influenza A viruses cause significant morbidity and mortality annually, and the threat of a pandemic underscores the need for new therapeutic strategies. Free full text available at Pubmed.
Free Full Text: Predominant Role of Bacterial Pneumonia as a Cause of Death in Pandemic Influenza: Implications for Pandemic Influenza Preparedness
Despite the availability of published data on 4 pandemics that have occurred over the past 120 years, there is little modern information on the causes of death associated with influenza pandemics. Free full text available at Pubmed.
Abstract: Emerging influenza.
In 1918 the Spanish influenza pandemic, caused by an avian H1N1 virus, resulted in over 50 million deaths worldwide. Several outbreaks of H7 influenza A viruses have resulted in human cases, including one fatal case. Since 1997, the outbreaks of highly pathogenic avian influenza (HPAI) of the H5N1 subtype have affected a wide variety of mammals in addition to poultry and wild birds. Abstract available at Pubmed.
Looking for a Top-Rated
Primary Care Physician, Pediatrician, or Pulmonologist?
Consumers' Guide to Top Doctors finds the Doctors Rated Best by other Doctors
To find out who the top doctors are around the country, nonprofit Consumers' CHECKBOOK surveyed roughly 340,000 physicians to tell us which specialists they would want to care for a loved one. The Top Doctors database contains the names of over 23,000 doctors who were mentioned most often. Find top-rated doctors in the fifty largest metropolitan areas, in over thirty-five specialties, and more.
Source: Cochrane Collaboration
Influenza A (H1N1) Essential Information
Click to read about Flu Research at the CDC
Consumers' Guide to Top Doctors finds the Doctors Rated Best by other Doctors in over 30 specialties.
database of 23,000 top-rated physicians by
Doctors database of 23,000 top-rated
(over 35 different fields included) Specialty
Find a Flu Shot
Consumers' Guide to Hospitals
Which Hospital Should You Choose (or Avoid)?
What makes the Consumers' Guide to Hospitals so special?
We've got 30 million answers to that question. That's how many hospital records Consumers' CHECKBOOK sifted through to calculate risk-adjusted death rates and adverse-outcome rates, and that's just part of the data used to rate the hospitals. The organization also sent out more than 280,000 questionnaires to physicians in 53 major metropolitan areas in the United States, asking them to rate their local hospitals; checked ratings of the hospitals by surveyed consumers; checked which hospitals were providing recommended tests and procedures for patients with specified medical problems; and more."
AARP The Magazine
View a flu.gov public service announcement
Flu Virus (Influenza A) Magnified