More and more parents are opting out of vaccinations for their kids.

In eight states now, more than 1 in 20 public school kindergartners aren't getting all the vaccines required for attendance, an Associated Press analysis found. That growing trend among parents seeking vaccine exemptions has health officials worried about outbreaks of diseases that once were all but stamped out.

"Study after study after study has shown that vaccines are safe, so why are so many parents still convinced it's not right for their children?" TODAY's Matt Lauer asked NBC Chief Medical Editor Dr. Nancy Snyderman.

Snyderman said it's not a lack of resources or education. The "profile" of the non-vax parent is middle-class, college educated and web-savvy, she said. There is also a new generation of parents in their 30s and 40s who "have no memory of polio, whooping cough and measles."

The problem is, there have been deadly outbreaks of measles and whooping cough in recent years. In California last year, 24 children died of whooping cough.

Secondly, Snyderman said, parents who opt out of vaccines put others risk. Infants who are too young for vaccines, people undergoing chemotherapy, anyone with a weak immune system could catch a disease from an unvaccinated child: "An un-immunized child is a walking Typhoid Mary who can put any of those immune-compromised people in an early grave," Snyderman said. "I personally think it is selfish not to think of that."

What do you think? Are parents who opt out of vaccines being reckless, or cautious?

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By Rachel Rettner

MyHealthNewsDaily

Young children who receive vaccinations against whooping cough are not fully protected against the disease three to six years after their shots, a new study suggests.

Currently, kids receive five doses of the pertussis vaccine, with the final injection given between ages four and six. A pertussis booster shot is recommended for adolescents.

In the new study, vaccinated kids developed pertussis anyway — and the number of pertussis cases progressively increased each year following the kids' final vaccination. Children were seven times more likely to develop pertussis six years after vaccination than one year after vaccination.

Researchers knew that pertussis vaccine protection waned with time. But studies had not looked cases of pertussis in vaccinated children this young before, said study researcher Sara Tartof, a medical epidemiologist at the Centers of Disease Control and Prevention.

The new findings underscore the importance of the booster shot for adolescents.

"It's really important for kids to get that booster at 11 or 12 years of age," Tartof said.

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The new findings are not enough to warrant a change in children's vaccination schedules, Tartof said. However, future studies should examine factors that may affect how much protection the vaccine gives, including the age at which it is given, Tartof said.

The first version of the whooping cough vaccine, known as the whole cell pertussis vaccine, had long lasting immunity. Its protection was thought to last much of life, said Dr. William Schaffner, chairman of the department of preventive medicine at Vanderbilt University. However, this vaccination often caused reactions at the injection site, such as redness and swelling.

Because of concerns about safety, a new, more purified version of the vaccine was created. Childhood vaccination with the acellular pertussis vaccines began in 1997, Schaffner said. Researchers are still studying how long immunity lasts with this vaccine.

The vaccines for diphtheria, tetanus and pertussis are given to children together in a single injection, nicknamed DTaP. Tartof and colleagues examined the immunization records of more than 220,000 children born in Minnesota between 1998 and 2003.

Information from the state's pertussis surveillance system was used to determine which kids came down with pertussis. Children were included in the study only if they received all five doses of the pertussis vaccine. They were followed for up to six years after their final shot.

Between 2004 and 2010, 358 cases of pertussis were identified in these kids.

A child's risk of pertussis increased each year after their final shot.

Children were 1.6 times more likely to develop pertussis two years after vaccination than in the first year after vaccination. That risk increased to 2 times more likely during year three, and 2.6 times more likely over year four, compared with the risk at year 1.

By six years after vaccination, the risk had increased to 7 times what it was in the first year.

Tartof noted that if vaccinated children develop pertussis, their condition is less severe if they have received all five shots.

The finding "highlights the fact that pertussis immunity can be short lived," said Dr. Paul Offit, chief of the director of the Vaccine Education Center at the Children's Hospital of Philadelphia, who was not involved in the study.

And the results suggest that it is not unreasonable to consider more frequent booster vaccinations among teens and adults, Offit said.

Technically a person's last pertussis vaccination may be when they receive their booster at age 11 or 12 years old, Offit said. However, it's important that people in older age groups have immunity against pertussis because of the risk they may transmit the disease to infants.

Babies less than 6 months old are at greater risk of dying from pertussis, and they cannot begin to be vaccinated until they are two months old. Doctors want to "cocoon" infants by vaccinating all the adults and teens around them, Offit said.

The outbreaks of pertussis that have occurred in recent years are likely due to people deciding to forego vaccination, Offit said.

"When you make a choice not to vaccinate, then you are in trouble," Offit said. "Because the disease is always going to be around."

The study results argue for the enforcement of pertussis boosters in middle school childnren, Schaffner said. Without booster shots, there may be outbreaks of pertussis among this young population, he said.

By Dr. Tanya Altmann

Break out the tissues – it’s flu season! Day care facilities and classrooms will soon be filled with sick children performing the music of cough cough, sneeze sneeze, achoo! 

So how do you keep your children safe from the common cold and flu this winter?

For the common cold, there’s no magic pill. The best prevention is simply frequent hand washing along with plenty of sleep, exercise and a healthy diet.

To avoid the flu, there’s a less time-consuming but very effective answer: the flu vaccine.

Here are the most common questions parents are asking this year about the flu vaccine. 

1.  Who should get flu vaccine?

Everyone 6 months of age or older should receive the flu vaccine. If you have a baby younger than 6 months of age, you can protect him from catching the flu by vaccinating everyone else in your house. So roll up your sleeve (or take a big sniff) to protect your child.

2. What’s the difference between the flu shot and the flu mist?

There are two types of flu vaccines:

The flu shot is an inactivated or killed virus vaccine. The flu shot can be give to anyone 6 months of age and older, even if you have a chronic medical condition.

The nasal-spray flu vaccine, called flu mist, is made with live, weakened flu viruses.  The flu mist is a nice option for healthy people 2-49 years of age.  Many of my patients and my own boys prefer the flu mist because it’s not a shot.  Even my husband chose the mist this year. 

There are some people who cannot get flu mist: If you are pregnant, have a history of asthma or wheezing or have a chronic medical condition such as heart or lung disease you should get the shot, not the mist.

3.  Does this year’s flu vaccine cover H1N1?

Yes.  The flu vaccine is updated each year to combat the influenza virus that changes so often. This year there is only one flu vaccine that contains two strains of Influenza A (H1N1 and H3N2) and Influenza B.

It takes up to two weeks for protection to develop after the shot and protection lasts about a year.

4.  Can you catch the flu from the flu vaccine?  Are there any side effects?

Contrary to popular belief, you can’t catch the flu from the flu vaccine.  The flu shot is a killed virus and other than a sore arm, side effects are rare.  The viruses in the nasal-spray vaccine are weakened so you will not get the flu or severe flu symptoms. Some people report mild cold symptoms and rarely a child will have a fever after the vaccine.  My office has already given 1,500 flu vaccines this season and we have not had any serious side effects or calls from parents reporting side effects or symptoms after the vaccine.

5. Why do some kids need two doses?

For children under age 9, if this is the first year your child is receiving the flu vaccine, if he didn’t receive two doses of the seasonal flu vaccine a prior year or if he didn’t receive at least one dose of the H1N1 flu vaccine last season, he needs two doses of this year’s flu vaccine, given at least four weeks apart.  One bit of good news: The flu vaccine can be given at the same time as other childhood immunizations, so it won’t put your little one behind schedule.

 6. What are symptoms of the flu?

The flu can cause fever, cough, sore throat, headache, chills and muscle aches.  Most are sick for a few days to a week, but some people get much sicker and may even need to be hospitalized.  Believe it or not, the flu still causes thousands of deaths each year. 

7.   Can I get the flu vaccine if I have an egg allergy?

Both the flu shot and the flu mist use egg protein in the production process.  The vaccine contains a very tiny amount of egg protein, so small that most patients with an egg allergy tolerate the vaccine without any reaction.  If you or your child has an egg allergy, an allergist can administer a small amount of the vaccine to see if there is any allergic reaction.  If there is no allergic reaction, they will then give you the rest of the flu vaccine. 

8.  Can I get the flu vaccine if I am pregnant or breast-feeding?

Definitely!  Pregnant women are at a higher risk of having complications if they catch the flu so if you are pregnant, ask your Ob for a flu shot right away. Breast-feeding women can get either the inactivated flu shot or the life flu nasal spray vaccine.  Nursing women will help protect their baby from catching the flu by breast-feeding and getting vaccinated.

 9.  Can I get flu mist if I am around people with weakened immune systems?

In most cases you can, for example, if you have a newborn in the house or a family member who takes steroids or who has HIV.  If you have a family member with a severely weakened immune system, such as somebody who is on chemotherapy or has recently undergone a bone marrow transplant, than it’s best to opt for the flu shot.  If you have any questions, talk to your doctor.

10. Other ways to prevent illness this winter?

The best way to stay healthy this flu season is to make sure the whole family gets flu vaccines, washes their hands, eats healthy, exercises, gets plenty of sleep and gets regular checkups. And make sure to see your physician if you have questions.

Dr. Tanya Remer Altmann is a best-selling author, parenting expert and media spokesperson, a working mother and UCLA-trained pediatrician who practices in Southern California. Visit her website at Dr.Tanya.com.

Is your family prepared for flu season? What steps have you taken? Watch the video and share your thoughts in the comment section below.

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