The Norman Transcript

Community News Network

December 5, 2012

How animals spread diseases to us

IOWA CITY — "Everybody knows that pestilences have a way of recurring in the world; yet somehow we find it hard to believe in ones that crash down on our heads from a blue sky." — Albert Camus, "The Plague"

In May, 1997, a 3-year-old boy was admitted to an ICU in Hong Kong after suffering from influenza for a week. Two days later, the boy died of pneumonia. His case would have been merely a curiosity if it weren't for 17 more patients who came down with the illness months later. In all, six people died from a strain of influenza that had never been seen in humans before, dubbed H5N1.

However, H5N1 wasn't really "new." It had caused outbreaks in Scottish chickens in 1959 and British turkeys in 1991. It had killed geese in Guangdong, China, in 1996. But these bird outbreaks weren't considered important by physicians or researchers on human disease — this was an avian strain of influenza, and it was thought that humans had little to be concerned about.

That changed abruptly in 1997, when the human cases led to the destruction of 1.3 million chickens in Hong Kong to stop the outbreak. That strategy seemed to work in the short term, but H5N1 has since surfaced in more than two dozen countries and caused more than 600 human infections since 1997 — almost half of them fatal.

While scientists were closely following the movements of H5N1, another influenza virus — H1N1 — snuck up on us in 2009 and spread around the world in a matter of weeks. This was the first influenza pandemic of the 21st century, and like H5N1, it moved to humans from animals — in this case, from pigs.

When new infectious diseases are discovered, one of the first questions is "where did this come from?" More often than not, the answer is one of our animal friends — a kind of disease called a zoonosis. Studies have shown that about 75 percent of emerging infectious diseases (diseases that are newly discovered, are increasing in frequency or have moved into a new geographic area) are of animal origin, as are 60 percent of all known pathogens. Even diseases that have spread freely in the human population, such as tuberculosis, HIV, measles and smallpox, have their roots in infections carried by animals.

Text Only | Photo Reprints
Community News Network
  • The case for separate beds

    The other night I slept on a twin bed in the guest room of the house I share with my husband and our two kids.
    It was the best night's sleep I've had in years.

    April 17, 2014

  • Raw oysters spike U.S. rise in bacterial infections, CDC reports

    Raw oysters, so good with hot sauce, increasingly can carry something even more unsettling to the stomach: A bacteria linked to vomiting, diarrhea and pain.

    April 17, 2014

  • To sleep well, you may need to adjust what you eat and when

    Sleep.  Oh, to sleep.  A good night's sleep is often a struggle for more than half of American adults.  And for occasional insomnia, there are good reasons to avoid using medications, whether over-the-counter or prescription.

    April 16, 2014

  • Doctors to rate cost effectiveness of expensive cancer drugs

    The world's largest organization of cancer doctors plans to rate the cost effectiveness of expensive oncology drugs, and will urge physicians to use the ratings to discuss the costs with their patients.

    April 16, 2014

  • Low blood-sugar levels make for grousing spouses

    Husbands and wives reported being most unhappy with their spouses when their blood-sugar levels were lowest, usually at night, according to research released this week in the Proceedings of the National Academy of Sciences. Missing a meal, dieting or just being hungry may be the reason, researchers said.

    April 16, 2014

  • Screen Shot 2014-04-16 at 12.51.22 PM.png VIDEO: Toddler climbs into vending machine

    A child is safe after climbing into and getting stuck inside a claw crane machine at a Lincoln, Neb., bowling alley Monday.

    April 16, 2014 1 Photo

  • portraitoflotte.jpg VIDEO: From infant to teen in four minutes

    Dutch filmmaker Frans Hofmeester’s time lapse video of his daughter, Lotte — created by filming her every week from her birth until she turned 14 — has become a viral sensation.

    April 16, 2014 1 Photo

  • Victimized by the 'marriage penalty'

    In a few short months, I'll pass the milestone that every little girl dreams of: the day she swears - before family and God, in sickness and in health, all in the name of love - that she's willing to pay a much higher tax rate.

    April 15, 2014

  • Allergies are the real midlife crisis

    One of the biggest mysteries is why the disease comes and goes, and then comes and goes again. People tend to experience intense allergies between the ages of 5 and 16, then get a couple of decades off before the symptoms return in the 30s, only to diminish around retirement age.

    April 15, 2014

  • treadmill-very-fast.jpg Tax deduction for a gym membership?

    April marks another tax season when millions of Americans will deduct expenses related to home ownership, children and education from their annual tax bill. These deductions exist because of their perceived value to society; they encourage behaviors that keep the wheels of the economy turning. So why shouldn't the tax code be revised to reward preventive health?

    April 15, 2014 1 Photo

Video
Facebook