On June 11, 2009, swine flu H1N1 became a pandemic, or worldwide epidemic. What is swine flu, and how did it all begin?
In late April 2009, a swine flu epidemic hit the U.S. and Mexico. The virus, known as influenza Type A H1N1, causes a respiratory, flu-like infection of pigs and can accidentally infect humans who are in close contact with pigs harboring the virus. Mutations in the DNA of the virus can lead to person-to-person spread and potentially lead to epidemics of global proportions.
Swine Flu Pandemic of 2009: An Overview
According to the World Health Organization (WHO), the Mexican government first reported influenza-like illnesses on March 18. By April 23, more than 854 cases of pneumonia and 59 pneumonia-related deaths occurred in Mexico City. In other parts of Mexico (San Luis Potosi and the city of Mexicali), a total of 28 cases and 3 deaths of pneumonia were reported. At this early stage of reporting, the Mexican cases had not been confirmed to be swine flu, but most of them have now been confirmed as influenza.
Shortly after the Mexican government reports, the U.S. government began reporting laboratory-confirmed cases of swine flu H1N1 as well. Between April 26th and May 6th, the number of reported U.S. cases gradually increased from 20 cases across 5 states to 642 cases across 41 states. Two deaths occurred in the US. One death occurred in a Mexican toddler who was visiting relatives in Texas, and one in a 33-year-old American woman, also in Texas. Both had underlying health conditions that may have played a role in the severity of infection.
Each week since the epidemic started, the numbers increased to countries in both the Northern and Southern hemisphere, with the WHO announcing that the H1N1 virus reached pandemic phase on June 11, 2009.
For a historical summary of the pre-pandemic scare, see:
- April 25, 2009 – Swine Flu Epidemic in Mexico, California, and Texas
- April 26, 2009 – Reasons NOT to Panic… Yet
- April 27, 2009 – When SHOULD You Panic?
- April 28, 2009 – Keeping Things in Perspective
- April 29, 2009 – Swine, the Other White Meat
- April 29, 2009 – Pandemic Phase 5
- April 30, 2009 – How Influenza Kills
- May 1, 2009 – A Mother’s Perspective
- May 2, 2009 – Virulence and Origin of the Swine Flu Outbreak
- May 3, 2009 – Person-to-Pig Spread - Spare the Pigs!
- May 6, 2009 – Swine Flu Claims First American Victim
- May 6, 2009 - Good News, Bad News: Schools Re-Opened
- May 22, 2009 - Travels to Mexico
- June 10, 2009 - Impending Pandemic
- June 11, 2009 - Pandemic Alert Phase 6 and Fashion Face Masks
Pandemic Alert Phases
The WHO raised its pandemic alert phase from Phase 3 to Phase 4 on April 27th, and from Phase 4 to Phase 5 on April 29th. Pandemic alert Phase 6 was announced on June 11, 2009.
For a simple tutorial of the WHO pandemic alert phases and what this means to you, see:
Swine Flu Pandemic Alert Phases
Pork: Should I Hold the Bacon?
Because of confusion over the name “swine flu,” many people mistakenly believed that this strain of influenza could be acquired through consumption of pork and pork products. In Egypt, 400,000 pigs were slaughtered as a consequence of this misconception. The WHO began referring to the virus as “influenza A (H1N1)” on April 30th, in order to alleviate the pork industry from economic downfalls due to these misconceptions.
To understand why you cannot get swine flu through eating pork, learn how swine flu spreads and why eating pork is safe:
Can I get swine flu from eating pork?
Death by Influenza
Although the disease appeared to be mild in most cases, and the number of deaths due to swine flu was small (compared to seasonal influenza) many people were concerned about the risks of dying.
To learn more about how influenza kills, see:
How Deadly Is the Swine Flu Outbreak Strain?
Within the U.S., there has only been one death (as of May 3, 2009) in a toddler who traveled to Texas from Mexico. There have been a handful of hospitalizations, but most cases appear to be mild. The greater number of deaths in Mexico have been attributed in part to poor nutrition, poor air quality, and poor health care, as well as to patients seeking medical help at late stages of disease. Genetic analysis of the outbreak strain has shown that it is missing parts of the DNA that made the Spanish Flu strain of the 1918 epidemic so deadly.
To learn more about how lethal the outbreak strain of swine flu is, see:
How deadly is swine flu?
Frequently Asked Questions
Harvard Medical School has provided a list of frequently asked questions about swine flu. To learn more about swine flu, see:
Sources:
Swine Flu FAQs
Centers for Disease Control and Prevention. H1N1 Flu (Swine Flu). http://www.cdc.gov/h1n1flu/. Accessed April 24 – May 6, 2009.
World Health Organization. Epidemic and Pandemic Alert and Response. Influenza A (H1N1). http://www.who.int/csr/disease/swineflu/en/index.html. Accessed April 24 – May 6, 2009.
