You know the flu shot is the number one way to protect yourself from the virus that can leave you feeling like you've been rammed by a bus for up to two weeks. But what you may not know is that it's ideal to get jabbed in the morning. A recent U.K. study found that, compared with folks who got immunized between 3 p.m. and 5 p.m., people who received shots between 9 a.m. and 11 a.m. had significantly higher levels of the antibodies for two flu strains one month later. It may have to do with the natural daily cycle of immune cells. So, if you can, head to the clinic early.
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You eat well and exercise. Get routine checkups. Buckle up in the car. But theres probably still one more item to add to your health to-do list: Get vaccinated. Its not just for the under-18 set. Adults are getting seriously sick from vaccine-preventable diseases like whooping cough (cases of which doubled between 2007 and 2010) and seemingly no-big-deal illnesses like influenza, which causes thousands of U.S. deaths each flu season. The fact is, we've been having our kids immunized successfully for decades in this country, but many of us haven't heard the news that we need to get vaccinated, too. "Many adults don't know what vaccines they're supposed to get," says Deborah F. Wexler, MD, executive director of the Immunization Action Coalition in St. Paul, Minnesota. "They're generally healthy, so they don't go to the doctor much, and they don't hear about it." To keep from missing out on the shots you truly need, ask your doctor about these key vaccines ASAP.


What's involved: One shot every year
Who needs it: Everyone over 6 months old
Why its worth it: Influenza viruses and their complications (like pneumonia) cause more deaths in the U.S. than any other vaccine-preventable illness. And if you're pregnant, the vaccines a two-fer: First, it protects you, since theres a higher risk for being hospitalized with the flu when you're pregnant than when you're not. Second, research suggests that babies born to moms who get vaccinated when they're pregnant are also protected from the flu for their first six months of life (after that, they're old enough to get their own vaccine).

Don't be scared off by the myth that the flu vaccine can give you the flu. Flu shots contain an inactive virus, but even the live virus in the nasal spray version has been modified so that it cant reproduce in your body (and thus make you sick). That said, you might get a runny nose or slight fever after receiving either form of the vaccination, but "thats just your immune system responding to the vaccine—its not the actual flu," assures Melinda Wharton, MD, deputy director of the Centers for Disease Control and Prevention (CDC)s National Center for Immunization and Respiratory Diseases.

Tetanus, Diphtheria, Pertussis (Tdap)

What's involved: On A one-time shot
Who needs it: All adults, even if you got a tetanus booster shot within the last 10 years
Why its worth it: This combo shot protects you from getting—or spreading—pertussis (a.k.a. whooping cough). "The coughing from pertussis can be so severe that ribs can fracture, and people can black out because they cant take a deep breath," says William Schaffner, MD, president of the National Foundation for Infectious Diseases. Also bad news: It can take 10 weeks—or longer!—for pertussis to run its course. Even adults who were immunized as babies need this shot, since protection can fade over time. You especially need it if you are pregnant, are thinking of getting pregnant, or just had a baby: Pertussis is extremely dangerous to babies under a year old (who are too young to be fully vaccinated), because they may have symptoms like convulsions and pneumonia, often leading to hospitalization. In fact, infants account for the vast majority of deaths from pertussis. Anyone else who spends time with a baby—siblings, grandparents, babysitters—should be immunized too.

Human PapillomaVirus (HPV)

What's involved: A one-time series of three shots: two shots, four to eight weeks apart, with a booster six months later
Who needs it: Typically, this vaccine is touted for women and men up to age 26, since anyone older has likely already been exposed to HPV, the most common sexually transmitted infection. But gynecologists such as Lauren Streicher, MD, assistant professor of obstetrics and gynecology at Northwestern Universitys Feinberg School of Medicine, feel that any sexually active woman who's not in a monogamous relationship could benefit from it. That's because while women ages 20 to 24 do have the highest infection rates—nearly 45%—women past that age may not have been exposed to every form of the virus the vaccine protects against. In fact, one study found that about 12% of women over 45 have new infections. "If you're concerned, or if you're newly dating or sexually active, talk to your doctor," says Dr. Wexler. "Its not FDA-approved for people over 26, but that doesnt mean it cant be given." (Your insurance may not cover it, though. The cost for you: anywhere from $125 to $300 a shot.)
Why its worth it: The Cervarix vaccine protects against the HPV types that cause cervical, vaginal, vulvar, anal, and throat cancers; the other vaccine, Gardasil, safeguards you from those cancers, as well as genital warts. Ask your doc which ones right for you.

Hepatitis B

Whats involved: A one-time series of three shots: two shots four weeks apart with a booster six months later
Who needs it: Anyone whos sexually active and not in a monogamous relationship; healthcare workers; people with HIV or liver disease; IV drug users
Why its worth it: Hepatitis B, spread during childbirth or through sex or needle-sharing, raises your risk of cirrhosis and liver cancer. If you were born before 1991, when the shot started to be given routinely, its worth the needle now: Hep B may cause gastrointestinal problems, fatigue, joint pain, or jaundice, but it often has no symptoms, only showing up in a blood test—meaning you could be infected (and pass it on) without even knowing it. The good news (for the next generation, at least): These days, babies are vaccinated against it, making them immune for life.