Vaccines, it turns out, aren't just for children.
Long the purview of the pediatrician's office, immunizations are often forgotten about once patients turn 18. But the Centers for Disease Control and Prevention, as well as leading doctors' organizations, recommend that adults continue to receive certain routine shots throughout their lives to keep up immunity against infectious diseases, from tetanus and whooping cough to pneumonia and shingles.
"A lot of adults think it's the thing you get as a kid and once you're an adult you don't need them," said Dr. Vincenza Snow, director of clinical programs and quality of care for the American College of Physicians in Philadelphia.
But adults do need vaccines - and their busy doctors don't always have the time to make sure their immunizations are up to date.
"All doctors want to do the right thing, but sometimes the real-life visit gets in the way," Snow said. "If they're in for chest pains during flu season, these things tend to get forgotten, or we say [we'll] get the flu shot on the next visit, but the next visit doesn't happen."
The flu shot is the vaccine we hear about most, because influenza kills thousands each year and puts tens of thousands in the hospital. People older than 50 and those with chronic health problems should get flu shots. Primary-care doctors often administer them at their offices, while workplaces and grocery store chains also offer clinics to get as many adults vaccinated as possible.
And even then, only about 70 percent of Americans older than 65 get their yearly flu shots.
"People are not receiving the vaccines they should," said Dr. Gina Mootrey, associate director for adult immunizations at the CDC.
A number of surveys have been done, she said, asking adults whether or not they get vaccinated and, if not, why not. While some parents have worried about the safety of vaccination for their children, safety does not appear to be a major concern when it comes to their own shots.
"The most common reason is they did not know they needed the vaccine," she said.
Vaccines are considered one of the greatest public health advances of the 20th century, leading to the near eradication of many diseases in the United States and saving countless lives. In many ways, vaccines are a victim of their own success. Those who weren't around when diphtheria and tetanus were serious health threats in the U.S. may question the need for vaccination against those diseases or forget about them entirely.
"There are risks associated with giving vaccines and they're usually very minimal," said Dr. Robin Motter, a family physician in Hunt Valley. "The risk you encounter if you don't get a vaccine can be life-threatening."
Some childhood vaccines give lifelong immunity, but the effects of others wane over time. To that end, the CDC recommends that every 10 years, adults get a booster shot containing a vaccine against tetanus, diphtheria and pertussis (Tdap) - and not just when they step on a nail.
But that's typically when most adults think about booster shots. A 2002 survey showed that in the previous 10 years, only 57 percent of adults ages 18-49 had received the booster. Only 44 percent of those older than 65 were vaccinated over the same period, Mootrey said.
"People don't like shots," she said.
Some vaccines recommended by the CDC are newly licensed and have not had time to completely take hold. The vaccine against the Human Papillomavirus (HPV), for example, is recommended for women through the age of 26. Girls tend to get their first of three doses of the Gardisil vaccine when they are 11 or 12, before their first sexual encounter, to protect them from contracting the virus, which can lead to cervical cancer later in life.
It is controversial in some circles - despite the proven safety and effectiveness of the vaccine. Some parents are uneasy having their pre-adolescent daughters vaccinated against a disease that is clearly related to sexual activity, especially when they still consider them little girls, said Dr. William Schaffner, chairman of the department of preventive medicine at Vanderbilt University School of Medicine in Nashville, Tenn.
But young adults who haven't been immunized really ought to be, he said.
Another one that hasn't caught on is the zoster vaccine, which immunizes against shingles. The shingles vaccine is relatively new and is recommended for people 60 and older. Schaffner, who with his wife was part of the clinical trial testing the shingles vaccine several years ago, said only 2 percent to 8 percent of senior citizens have been vaccinated.
"A lot of people don't know it's available," said Schaffner, who is also president-elect of the National Foundation for Infectious Diseases. "Doctors are not integrating it into their practices."
There's been a shortage of shingles vaccine this year because it uses the same basic material as the shot for chickenpox, and some states have started recommending a second dose of chickenpox vaccine for children who have received one dose. The shortage is expected to ease shortly, however, Mootrey said.
At the same time, Schaffner said some doctors don't push vaccination because some insurers don't cover it.
Many of the diseases for which there are vaccinations are no longer fatal. But being immunized protects others - including babies too young for certain shots and for whom such diseases would be extremely dangerous - from getting sick.
"We protect more than just ourselves," Snow said. "We're protecting our entire community."
Motter, who is chair of family medicine at Greater Baltimore Medical Center in Towson, generally discusses immunization with her patients when they come in for an annual physical. She also thinks about vaccines in general during flu season.
"When I'm talking about their flu shot, I look down their chart to see if they're up-to-date on everything else," she said.
Sometimes, patients are the ones who ask about immunizations, especially if they are planning to travel internationally. But mostly it's up to her to initiate the conversation.
Senior medical secretary Yvette Gouchenour has worked in health care for years, the past 14 in the medical office where Motter works. She knows that it is standard procedure to encourage proper vaccination. She knows that the CDC recommends people in her field receive the three-dose hepatitis B vaccine. Still, it wasn't until last week that Motter gave Gouchenour her final hepatitis B shot. Gouchenour blamed convenience for the many-year delay.
"You want to limit your risk to any disease," she said. "In health care, you have that risk every day."