How long does it take people to die from the Swine Flu once they begin to have symptoms?

Answer 1

For most people it is like an ordinary flu, just a little bit worse, and most people recover. But in those who don't, usually how long it takes depends upon the state of health of the person when they got it (as with any disease).

The flu may elevate to a severe respiratory illness within as soon as five days from the first symptoms and require hospitalization. This severe illness may include primary influenza viral pneumonia which is often the cause of death in any type of influenza.

Influenza virus infections can make underlying medical conditions (e.g., asthma, Diabetes, other pulmonary or cardiac diseases-see below for more examples) much worse; lead to secondary bacterial pneumonia, sinusitis, or middle ear infections; or, contribute to other viral or bacterial infections once the immune system is stressed.

The mortality rate of the 2009 Novel H1N1 Influenza (Swine Flu) during the pandemic has been very low, not nearly as high as was feared. Based on formulas for the calculations of mortality rates from the US Centers for Disease Control and Prevention (CDC) that estimate the total numbers of cases (since it is suspected more and more that many cases of H1N1 have gone unreported, untested, and or unrecognized by those infected due to mild symptoms in some people) the rate of deaths is lower than that seen in the seasonal flu each year. The CDC has estimated that, as of 2/12/10, since the beginning of the pandemic in Spring 2009, the US has had approximately 57 million cases of A-H1N1/09 Pandemic Swine Flu and approximately 11,690 resulting deaths. Based upon this, an estimate of the mortality rate in the US from the pandemic is 0.02%.

In comparison, the CDC and World Health Organization (WHO) have estimated that with seasonal flu, "we see over 30 million cases in the United States. We see 200,000 hospitalizations and, on average, 36,000 deaths." (During the entire fall and winter flu season.) Based upon this, the average mortality rate of seasonal flu in the US would be 0.12 %.

The initial Death Rate of Novel H1N1 indicates it is a milder infectious agent than feared. However, in some epidemics of flu in the past, a second more lethal wave has occurred after an initial mild wave of the flu (such as the 1918 Spanish Flu pandemic). The World Health Organization and Centers for Disease Control and Prevention are recommending continued vigilance and precautions such as frequent hand washing to continue to help reduce the spread of the virus.

Examples of conditions that put people at higher risk of infection and death from Novel H1N1 Influenza:

According to the studies conducted so far by the Centers for Disease Control and Prevention, those people at high risk of these severe symptoms of the flu include the same groups who are at higher risk with the regular seasonal flu viruses:

• Children younger than 5 years old;
• persons aged 65 years or older--(with Novel H1N1, this does not hold true, for unknown reasons, this age group is actually less likely to be infected, perhaps immune due to exposure to a similar flu in ages past);
• children and adolescents (younger than 18 years) who are receiving long-term aspirin therapy and who might be at risk for experiencing Reye syndrome after influenza virus infection;
• pregnant women;
• adults and children who have underlying conditions such as:
  • pulmonary, including asthma,
  • cardiovascular,
  • hepatic,
  • hematological,
  • neurologic,
  • neuromuscular, or,
  • metabolic disorders, such as diabetes;
• adults and children who have immuno-suppression (including immuno-suppression caused by medications or by HIV);
• residents of nursing homes and other chronic-care facilities: and,
• the morbidly obese

(See related questions below for more information.)