It's irresponsible not to get a flu shot

It's that time of year again.

And if you're thinking of skipping out on your annual flu vaccination, you should seriously reconsider.

Getting vaccinated doesn't just decrease your chances of getting the virus - it helps protect everyone around you.

This is especially important because while healthy young adults probably won't die from an ordinary strain of flu, the virus can kill older people, young children, and others whose immune systems may not be equipped to fight it off.

When the flu can be deadly

Every year, thousands of people die as a result of the flu. In 2006, more than 50,000 Americans died as due to complications from the virus, and an estimated 20,000 children younger than 5 are hospitalized due to the flu every year.

During a typical flu season, close to 90% of all deaths from the virus occur in people over 65. Young people are also especially vulnerable to the virus, particularly those younger than six months.

While some groups lack easy access to the vaccine or are ineligible for vaccination - infants are too young to get it and it is less effective in those with compromised immune systems, like certain cancer patients - others simply fail to get their yearly shot.

You can help protect the most vulnerable groups by getting vaccinated yourself.

The key principle guiding most vaccinations is herd immunity, the scientifically-proven concept that protecting enough people in any given community reduces the chances that anyone in that community will get sick.

If most people are vaccinated and can't get sick, widespread disease becomes nearly impossible, as even a rogue sick person is likeliest to come into contact only with people who are vaccinated. That means that, so long as a significant majority of people (75%, for the flu) in any given company or school or town is vaccinated, the chances that lots of people will get sick are slim.

Here's how it works:

Short, painless, and very low-risk

For your typical flu shot, you'll get your arm pricked with a dead version of the virus.

Not a fan of shots? You can also opt for the nasal spray vaccine, which contains a small amount of weakened live virus. (The spray cannot cause the flu, but it can lead to some mild symptoms, like a runny nose.) The inactive flu in the shot won't cause any symptoms.

Both the shot and the spray will prime your immune system to recognize the foreign virus: As soon as your body senses the virus' presence, it starts making antibodies, the special proteins it uses to neutralize hostile invaders. Primed from the dress rehearsal provided by the vaccine, the body knows what to do when the real thing arrives: It launches its practiced attack, killing off the virus before it has a chance to establish a foothold in your body.

The vaccine includes inert viruses from four types, or strains, of the flu that a team of international scientists determines will probably be the most widely-circulating each year.

So the shot won't make you completely immune to all flu viruses, but it will protect you against the worst offenders.

Don't delay. It takes about two weeks for the vaccine's full protective effects to take hold, so getting a flu shot as soon as possible is key to protecting yourself - and those around you.