But the CDC estimates that between 12, and 56, flu-related deaths occur each year. That's still a relatively small number, considering that the number of flu cases in a given year can clock in at up to Salber says. Some victims may contract a second infection while already battling the flu, like pneumonia an infection of the air sacs of the lungs , which can be severe enough to lead to organ failure and ultimately death, Dr.
The flu can be further complicated by sepsis , a life-threatening reaction to an infection that happens when bacteria have entered the bloodstream. Other people may die from the flu because their immune systems are already compromised by another illness.
Salber explains. But even healthy people can die of the flu, as news reports of deaths among children often suggest. In some cases, the body may increase immune defenses so much that infection-fighting proteins build up in the blood and damage other organs.
Older adults and young kids are most at risk for serious complications of the flu, including hospitalization and death. CDC conducts surveillance for people who see their health care provider for flu-like illness through the Outpatient Influenza-like Illness Surveillance Network ILINet ; a network of thousands of health care providers who report the proportion of patients seeking care for flu-like illness weekly to CDC.
This system allows CDC to track levels of medically attended flu-like illness over the course of the flu season. CDC does not know exactly how many people get sick with seasonal flu each year. There are several reasons for this, including that ILINet does not include every health care provider in the United States and that it monitors flu-like illness, not laboratory-confirmed flu cases.
Also, seasonal flu illness is not a reportable disease, and not everyone who gets sick with flu seeks medical care or gets tested for flu. To estimate the number of flu illnesses that occur in the United States each year, CDC uses mathematical modeling in combination with data from traditional flu surveillance systems.
CDC estimates that from to , flu has resulted in between 9 million and 41 million illnesses annually in the United States. Seasonal flu is associated with large numbers of hospitalizations. Flu vaccination is the first and best way to prevent flu and its serious complications. Everyone 6 months and older should get vaccinated against flu yearly, particularly people at increased risk for serious complications including young children, adults 65 years and older, and people with certain chronic medical conditions.
Before CDC had FluSurv-NET to gather data on laboratory-confirmed flu hospitalizations, CDC periodically made estimates of flu hospitalizations using a statistical model of data on hospitalizations with flu-like illnesses. A study conducted by CDC and published in the Journal of American Medical Association JAMA external icon external icon in September provided information on the number of people in the United States that were hospitalized from flu-related complications each year.
The study was based on records from to from about hospitals across the United States. The study concluded that, on average, more than , people in the United States are hospitalized each year for respiratory and heart conditions illnesses associated with influenza virus infections. Prior to that, in a paper published in , looking at records from — , CDC estimated that an average of , people were hospitalized as a result of flu-related infections each year 7.
The current methodology used to estimate flu-related hospitalizations is straightforward, uses directly observed hospitalization rates from FluSurv-NET surveillance data, and can be updated annually and, starting in , even during a flu season Previously it took longer to arrive at estimates because of delays in the availability of large administrative databases that were used in statistical models.
The estimated number of flu hospitalizations has always varied from season to season. In the past, CDC had referred to an average number of hospitalizations that was estimated based on statistical models using hospital discharge records from to from selected hospitals across the United States.
In addition to year-to-year variation, changes in health care practices and the increasing age of the US population, with a much greater number of adults over 65, may result in different numbers of flu hospitalizations now than in previous decades.
Because of these differences, it is challenging to directly compare current estimates of flu disease burden to those from many years ago.
CDC believes that using a range is a better way to represent the variability of flu. The more recent estimates use surveillance data on patients hospitalized with laboratory-confirmed flu in geographically distributed areas in the United States.
CDC releases preliminary flu burden estimates because some of the data used in the burden estimation model lag by 2 years. Providing preliminary estimates allows for the release of timely information about US flu burden, but also means that these preliminary estimates may change as more data become available.
Flu burden estimates are considered preliminary and subject to change until all data are complete. The network includes hospitals that serve roughly 9 percent of the U. The data collected through FluSurv-NET allows CDC to calculate an overall hospitalization rate, as well as by age group, but this system does not capture every flu hospitalization that occurs annually in the United States. To estimate the actual number of flu hospitalizations, reported FluSurv-NET hospitalization rates are adjusted to correct for under-detection and under-reporting.
Using this estimation model, CDC estimates that, from to , flu has resulted in between , and , hospitalizations each year. Seasonal flu-related deaths are deaths that occur in people for whom flu was likely a contributor to the cause of death, but not necessarily the primary cause of death. CDC does not know exactly how many people die from seasonal flu each year. There are several reasons for this. First, states are not required to report individual flu illnesses or deaths among people older than 18 years old to CDC.
Second, flu is infrequently listed on death certificates of people who die from flu-related complications. Also, most people who die from flu-related complications are not tested for flu, or they seek medical care later in their illness when flu can no longer be detected from respiratory samples sensitive flu tests are only likely to detect flu if performed within a week after onset of illness.
In addition, some commonly used tests to diagnose flu in clinical settings are not highly sensitive and can provide false negative results i. For these reasons, many flu-related deaths may not be recorded on death certificates.
Although the flu vaccine doesn't guarantee that you won't get sick, doctors say it does reduce the chances, and if you do get sick it may be less severe. If you develop flu-like symptoms , such as fever, body aches and fatigue, and you are at high risk for complications from the flu, it is important to see your doctor to ask if you should receive an antiviral medication such as Tamiflu also available as generic oseltamivir , Relenza or Rapivab.
Take common-sense precautions to avoid exposure to the flu virus, such as washing your hands frequently and staying away from people who are sick. Stay home if you have flu-like symptoms until at least 24 hours after the fever is gone. When the flu becomes severe, some people may need immediate medical attention to prevent further complications.
Flu deaths on the rise. Ashley Welch. Please enter email address to continue. Please enter valid email address to continue. Chrome Safari Continue. Be the first to know. Get browser notifications for breaking news, live events, and exclusive reporting.
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