By Dr. Marc SiegelAssociate Professor of Medicine, NYU Langone Medical Center/FOX News Medical Contributor

With a new swine flu strain spreading among close to 1,000 people in Mexico and at least eight in the U.S., and with 61 reported deaths in Mexico, the most powerful virus pushing out its tentacles is not flu but fear. We are afraid of what we don't know and what we don't understand.

We hear about an unseen killer and we worry that we will be next. The best antidote for this kind of fear is the facts.

So let me take on the fear-laden terms. The first is pandemic. A pandemic means a new flu virus infecting people in several areas of the world at the same time. It can be mild, moderate, or severe. Everyone knows about the 1918 Blue Death that killed over 50 million people worldwide, but how many people realize that the last pandemic, in 1968, ameliorated by vaccines, antibiotics, and public health measures, killed only 32,000 in the U.S. and 700,000 worldwide, less than many yearly outbreaks.

The current swine flu outbreak is not a pandemic, as the outbreak is confined mainly to Mexico, but if it does become one, it is far more likely to be the 1968 variety because of modern public health measures and because we have been exposed to several parts of this virus before and have an immune memory to it.

Precautions like isolating sick people and use of the anti-virals Tamiflu and Relenza in order to decrease severity are wise precautions.

Wise too is closing schools in Mexico to prevent spread (schoolchildren are notorious flu spreaders), provided that this measure doesn't send the world the wrong message that a massive pandemic is in the offing.

The second scare term is the pig itself. Pigs scare us. They are filthy noisy creatures. They are also loaded with flu viruses. This strain occurred because a bird virus mixed with at least one human virus and two pig viruses. -- Flus are changing all the time so a new strain isn't really a surprise.

We also need to be cautioned by the lessons of history. Back in 1976 an emerging swine flu virus appeared to be responsible for the death of a military recruit at Fort Dix (this later turned out to be erroneous), sparking a massive public hysteria fueled by Center for Disease Control press conferences.

I was reminded of this Friday when the CDC again spread fear about an emerging swine flu. We need to remember that fear causes people to take less precautions, but fighting contagions requires more precautions.

In 1976 Gerald Ford, trying for election, ordered 40 million vaccinations over a three to four month period of time, probably leading to almost 1,000 cases of ascending paralysis from the hastily made vaccine (Guillain Barre Syndrome) and driving most of the vaccine makers out of business. We certainly don't need a repeat of this performance, in advance of any real worldwide threat.

Thirdly, we are also afraid because this disease is emerging in Mexico, a foreign land to the south over which we have no control. But fear of an unknown land doesn't automatically translate to an American health risk. We are wise to have our scientists and public health officials tracking the outbreak, but we are not wise to anticipate the worst.

Like all flus, this one causes great fatigue, muscle aches, fevers, sore throat, nasal congestion, stomach upset, but is generally curable. The greatest risk is from secondary infections like pneumonia or ear infections, especially in the chronically ill. But in the U.S., if it spreads here, these problems are much more easily treated than in rural Mexico.

We should also be comforted by the time of the year. This is the end of the flu season, not the beginning. Flu viruses thrive in the low humidity of winter, not summer. It is very likely that this outbreak will die out automatically as the summer comes. It will remain necessary to track it because it could reappear in the fall, but it is very unlikely that it will erupt into a pandemic this summer.

I am glad that this outbreak is a swine rather than a bird flu, not because pig viruses are intrinsically safer than bird viruses, but because the greater lesson to guide us here comes from the 1976 pig hysteria, rather than from the 1918 bird flu plague.

Marc Siegel MD, an associate professor of medicine at NYU Langone Medical Center, is a FOX News Medical Contributor. He is the author of "Bird Flu; Everything You Need to Know About the Next Pandemic", and "False Alarm; the Truth About the Epidemic of Fear."