Swine Flu Epidemic

The swine flu (SIV) refers to an influenza sickness caused by any strain of the flu virus family that is common in swine (pigs). There is more than one type of this virus. Some types occur naturally in humans as well, but usually they are different.

People who work with chickens and pigs are at risk of infection from these animals if the animals carry a strain that is also able to infect humans. SIV can mutate into a form that allows it to pass from animals to humans and then to other people. The strain responsible for the current flu is like this.

In humans, the symptoms of swine flu are similar to those of normal influenza and flu in general. In most cases, it causes only mild symptoms. According to the Center for Disease Control and Prevention (CDC), in humans the symptoms can include fever, cough, sore throat, body aches, headache, chills and fatigue. A few patients also report diarrhea and vomiting.

This type of flu has actually been reported numerous times in humans but was rarely widespread. The worst was in the Spanish epidemic of 1918–19 that infected about one third of the world’s population (or around 500 million people at that time) and caused fifty million deaths.

The origins of this new strain are a mystery. One theory is that Asian and European strains traveled to Mexico in migratory birds or in people. It then combined with North American strains in Mexican pig farms before jumping over to farm workers.

So far this year, cases have been reported in parts of the United States, Mexico, and Canada. The new strain seems to be stronger and more severe than usual. More than 100 people have died. Medical authorities are urging people to wash more often and take other precautions to avoid infection.