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Ask the VEC

Early MMR vaccination for international travel

Q. My family is traveling abroad this summer and our son will be 11 months old at the time of our trip. Should he receive the MMR vaccine prior to traveling?

A. Yes. Because of the increased risk of exposure to measles in many other parts of the world, infants between the ages of 6-11 months should receive one dose of the MMR vaccine before traveling abroad. Also, children 12 months of age or older should receive two doses of MMR separated by at least 28 days. However, if your infant receives a dose of the MMR vaccine before his first birthday, he will still need two more doses to be in compliance for school vaccination requirements.


Newborns and hepatitis B vaccine

Q. Why should my newborn receive the hepatitis B vaccine if I know that I am not infected with hepatitis B virus?

A. Before the hepatitis B vaccine became a routine recommendation in 1991, every year about 18,000 children in the United States were infected with hepatitis B before they reached 10 years of age. Half of those 18,000 early-life infections were not contracted during birth from an infected mother. Instead, they were caused by exposure to someone who, knowingly or not, was infected with hepatitis B virus. Because the hepatitis B virus is present in such large quantities in the blood of someone who is infected, it can be transmitted through quantities of blood not able to be seen with the naked eye, such as from shared toothbrushes or washcloths. Because a large number of people infected with hepatitis B are unaware they have the disease, it is extremely difficult to be confident we can avoid the infection through our own actions.


"One-size-fits-all" schedule

Q. How can a “one-size-fits-all” approach to vaccines be OK for all children?

A. While a quick glance at many published schedules might suggest a “one-size-fits-all” approach, the reality is that the schedule is actually multiple pages in length and is supported by a 60-page “General Recommendations on Immunization” document and 25 to 40 page documents specific for each vaccine. These guidelines take into account many factors including individual differences in current and long-term health, allergies and age. So the truth is that the schedule isn’t “one-size-fits-all”; it’s what should be done for each patient depending on their medical history.


School vaccination rate look up

Q. How can I find out if children in my child’s class are vaccinated?

A. Parents have the right to question safety and health procedures at their children’s schools. How are children dismissed at the end of the day? How is the school prepared to handle a fire or an unwanted intruder? What type of supervision occurs on the bus or playground? Those questions have answers that schools are typically able to easily share as matters of policy. Unfortunately, when it comes to vaccination rates, the same is not often true.

However, in California the state health department has created a novel tool for parents that allows them to see immunization and exemption rates in schools throughout the state. As a part of Shots for School, the tool lets parents enter an address, zip code or school name and view that institution’s immunization rates for uptake of different mandated vaccines, the exemption rate and the percent of students with all required vaccines doses. The data is collected from child care facilities as well as kindergarten and seventh grade vaccination records.

Parents interested in the immunization rates in their children’s schools can check directly with the school or their local health department to see if this information is available. It may also be worth checking if your state would consider offering a similar program to the one in California.

Editor’s note: A reader subsequently shared with us the following resources for people in states other than California: About Pediatrics: School vaccination and exemption rates; USA Today immunization report.

Too young to get vaccines

Q. We have a newborn, and he is too young to receive the seasonal influenza vaccine as well as the first does of the measles, mumps and rubella vaccine. Given all the reports about measles, what can we do to protect him from vaccine-preventable diseases?

A. Unfortunately, when our babies are too young to be vaccinated, our best recourse is to keep them away from situations in which they may be exposed to infectious diseases — and even our best attempts are not always sufficient. When we go to work or have young children in school, diseases may come home. However, here are few tips to help avoid spreading illness to your newborn:

Where to find the game

Q. Where can I find the game online?

A. Vaccine Trivia: Just the Vax is on the Vaccine Education Center’s website and can be easily found by going to We hope you will remember the URL, play the game, and challenge your family and friends!

Is it too late for an influenza vaccine?

Q. Is it too late to get a seasonal influenza vaccine?

A. No, it’s not too late to get an influenza vaccine. Influenza season tends to peak between December and February, but may last throughout the spring. However, because it takes about two weeks to develop immunity after immunization, it is important to get immunized as soon as possible.  

Keeping a newborn healthy around the holidays

Q. We’re the proud parents of a newborn boy. He is too young to receive a flu shot and has just begun the recommended vaccine schedule. With the holidays coming up and many extended family members and visitors excited to meet him for the first time, how can we protect him from getting sick?

A. While your newborn is likely to be exposed to viruses and bacteria regardless of your efforts this holiday and winter season, you can take several steps to protect him while meeting relatives and friends:

Why do I need a flu shot?

Q. I never get the flu, so why do I need the vaccine?

A. Influenza can put a healthy person in bed for several days very quickly. Indeed, people who had influenza can often remember the exact hour they became ill. In addition to being severe for some, the virus can spread to others through coughs and sneezes. While measures like proper hand-washing, covering coughs, and avoiding others who are ill can help decrease the chance of getting influenza, the best protection comes from immunization because it provides specific immunity to the virus.

Additional resources for information related to the influenza vaccine 

Influenza: What you should know
A  Look at Each Vaccine: Influenza Vaccine

HPV vaccine for boys

Q. Why does my son need a specific HPV vaccine, while my daughter can receive one or the other?

A. There are two HPV vaccines available:

Because Gardasil offers protection from genital warts and Cervarix does not, Gardasil is the only one given to boys. Because this vaccine also affords more protection for girls, girls or their parents may want to ask which vaccine they are being offered as well. Although the CDC does not express a preference for girls, the truth of the matter is, if given the choice, most girls and their parents would likely also choose the vaccine that affords broader protection. 

State-by-state immunization laws

Q. My family is getting ready to move to a new state. Is there anywhere I can check to see immunization requirements in our new state?

A. Yes. the Immunization Action Coalition (IAC) website allows you to view state immunization laws for vaccine-preventable diseases in childcare facilities, schools, colleges and long-term care facilities, as well as which states allow pharmacists to administer vaccinations. The IAC also has a convenient list of all state immunization websites parents can use to find more specific information.

Measles protection before vaccination

Q. I have heard that measles is occurring in the U.S. If my child cannot get the MMR vaccine until he is 1 year of age, are there any other precautions I can take to protect him in the meantime?

A. Infants generally have protection from measles for several months after birth as a result of immunity passed on from their mothers. This is the main reason the measles vaccine is typically not given to infants younger than 12 months of age. However, if the child will be traveling outside the United States or if the risk is elevated in a particular geographic region because of an outbreak, the vaccine can be given as early as 6 months of age. If you are concerned, talk with your child’s doctor about whether this would be appropriate for your situation. You can also take precautions like avoiding contact with susceptible children, such as those whose parents have chosen not to vaccinate, and by keeping your child out of large groups if measles is circulating in your community.

Peanut allergies and vaccines

Q. My child has peanut allergies. Are there any vaccines that he should not get?

A. None of the routinely recommended vaccines contain peanut oils, so your child does not need to forego any immunizations for this reason. Similarly, we have been asked about corn allergies, and the same is true.

However, gelatin, eggs and latex are allergies that should be considered prior to getting vaccines. Latex is not in vaccines, but it is contained in some of the packaging.

Read more about allergies on the following pages of our website:

Traveling with children

The Vaccine Education Center recently released a new Q&A sheet related to travel called, "Infectious Diseases and Travel". So, in keeping with this month's travel-related theme, we thought we'd highlight a question from the new sheet that parents may have while traveling with their children:

Q. Are there special considerations for traveling with infants and children?

A. Parents traveling with infants and children should take the following precautions:

International adoption and Japanese Encephalitis (JE) vaccine

Q. My 2-year-old child recently moved to the U.S. from China where she had one dose of the Japanese Encephalitis (JE) vaccine as recommended, does she need the second dose now that she is here?

A. In the U.S., the Japanese Encephalitis (JE) vaccine is only recommended for people who are likely to be exposed to JE during travel. If your daughter will be making a trip back to China or to somewhere else that would increase her risk, then she would need to get the second dose. However, you should consult a travel clinic as the determination of need is based on trip-specific information, such as exactly where she is going, how long she will be there and what she will be doing.

You can find more detailed information on the CDC’s website:

Japanese Encephalitis Vaccine for U.S. Children »

Infectious diseases related to travel: Infectious encephalitis »

HIV vaccine

Q. Is there a vaccine to prevent human immunodeficiency virus (HIV)?

A. No, although researchers have been working to design a vaccine for many years, vaccine development has been difficult. HIV changes rapidly as it replicates in even a single individual. This makes HIV difficult to prevent because immunity provided by a vaccine against a previous version of the virus may be ineffective against a newer version of the virus.

Learn more or print “Special Topics: Human Immunodeficiency Virus”.

Too late for influenza vaccine?

Q. Is it too late to get the influenza vaccine? 

A. No, it is not too late to get the influenza vaccine. Although many people have been diagnosed with influenza in recent weeks, the season is expected to last until spring, so getting vaccinated would still be wise. The types of influenza that are circulating are contained in this year’s vaccine, but remember it takes about two weeks for protective immunity to develop after receiving the vaccine. So the sooner you get vaccinated, the better.

HPV vaccine questions

In honor of Cervical Cancer Awareness Month, we wanted to highlight some questions about the HPV vaccine that we recently received:

Q. Does the HPV vaccine cause infertility?

A. No. HPV infections do not cause infertility, except indirectly in cases when they progress to cervical cancer, so it does not make sense that the HPV vaccine would lead to infertility. To the contrary, since the HPV vaccine decreases the number of cases of cervical cancer, it may indirectly decrease the number of women unable to have a baby.

Q. How long does immunity last if you receive all doses of the HPV vaccine?

A. We do not know for sure whether immunity will last a lifetime; however, the data is reassuring. First, the vaccine has been studied for almost 10 years with no sign of waning immunity in those who received the vaccine that long ago. Second, the immune responses generated by the vaccine are stronger than those invoked after natural infection. Finally, the hepatitis B vaccine, which uses similar technology, induces a memory response that lasts at least 25 years.

To see our answers to additional questions that we have received about HPV and the HPV vaccine, visit our specialized web page,

Three-strain influenza vaccine or four-strain

Q. I heard some seasonal influenza vaccines have four strains of influenza virus and some have only three strains. Should I wait to get the four-strain version?

A. Although the four-strain version protects against an additional strain of influenza virus, it is more important to be vaccinated early enough in the season to have immunity when influenza arrives in your community. So, you should get whichever vaccine is available at your earliest convenience, keeping in mind that it takes about two weeks to develop immunity after vaccination.

Moderate side effects after DTaP vaccine

Q. My child cried inconsolably for three hours after she received the DTaP vaccine. Is it safe for her to receive another dose at her next appointment?

A. Because your baby experienced a reaction to the vaccine, it’s important to be sure your child’s doctor is aware of this and it is added to her medical record. The reaction your daughter experienced is considered to be a “precaution” to getting future doses of the vaccine, meaning that she can still receive future doses of the DTaP vaccine; however, the relative risks and benefits should be discussed with your child’s doctor before the vaccination is given.

Because pertussis, in particular, is circulating in many parts of the country and young infants are most susceptible to complications from the disease, you might still conclude that the relative benefits of the vaccine outweigh the risks. Previous experience has shown that in most cases, infants who experience inconsolable crying after the first dose of DTaP do not experience the same reaction after subsequent doses.

Questions about influenza

Over the past weeks we’ve received some questions about the influenza vaccine that might also be helpful for you to know the answers to.

Q. Are there risks of influenza from the nasal spray vaccine entering the brain and causing an infection like encephalitis?

A. Even during influenza infections, encephalitis is not a complication because influenza viruses are not able to reproduce in brain cells. In addition, the way the intranasal influenza vaccines works is that the virus reproduces a small number of times in the cooler temperatures of the nasal passages, but cannot reproduce in the warmer temperatures in the lungs, which is where influenza viruses typically reproduce and cause infection. It is not likely that the virus would enter the brain; however, because the virus can only grow at the cooler temperatures of the nose, in the same way that it cannot reproduce in the lungs, it would not be able to reproduce in the brain either.

Q. I am wondering whether or not to give my child the flu vaccine because my grandfather died in his 20s from Guillain-Barré syndrome.

A. The risk of a child dying from influenza is greater than the risk of developing Guillain-Barré syndrome (GBS). Influenza deaths happen in a number of children every year, and Guillain-Barré syndrome has not been shown to be caused by the influenza vaccine. Here is some additional information:

Q. When is the best time for me and my family to receive the influenza vaccine?

A. Influenza season can start as early as the fall, so the American Academy of Pediatrics (AAP) recommends receiving the influenza vaccine as soon as it is available. Because it takes about two weeks after receiving the vaccine for you to be fully protected, it’s important to get the vaccine early. This is especially important for children and adults with higher risk of suffering complications from influenza.

People at increased risk of experiencing complications include young children, pregnant women, adults 65 years of age and older, and individuals with underlying medical conditions, such as chronic heart, lung and kidney conditions.

Q. I feel like the flu vaccine doesn’t work because every year I still get the flu even though I was vaccinated.

A. Influenza vaccine protects against three or four influenza viruses expected to circulate during influenza season. However, two other factors should be considered.

First, some years the vaccine strains are not as good of a match with the circulating strains as we would like. In these cases, people who were vaccinated may still get influenza. For most of them, their disease will be less severe and shorter than if they had not been vaccinated.

Second, during the period when influenza is common, many other viruses are also circulating. Often these viruses cause colds and other illnesses that cause flu-like symptoms, such as congestion, runny nose, sneezing, coughing, sore throat, vomiting, nausea and diarrhea. Sometimes people with these symptoms will attribute them to influenza even though the virus is not to blame for the illness.


Ask the VEC goes mobile

Have you ever had a question about vaccines, but didn’t have time get to the computer? If so, we have great news! You can now send the Vaccine Education Center your questions whenever you’re on the go. Our Vaccines on the Go: What You Should Know app includes an “Ask the VEC” button at the bottom of the page in the following sections of the app: “Vaccines,” “Safety” and “About Us.”

Learn more about the app and download it today»


Traveling abroad during measles and rubella outbreaks

Q. I have a trip to Europe planned but am worried about the measles and rubella outbreaks happening there. Should I postpone my trip?

A. Although the U.S. Centers for Disease Control and Prevention (CDC) has not issued measles-related travel alerts at this time, they have issued rubella-associated travel alerts for people who are traveling to Japan and Poland. The CDC recommends travelers to Japan and Poland practice enhanced precautions and make sure they are immune to rubella prior to traveling. Pregnant women who are not immune to rubella (either by previous rubella vaccination or infection) should not travel to Japan or Poland during these outbreaks.

If traveling to a country where measles or rubella outbreaks are occurring, the following precautions should be taken:

All travelers should also be mindful of their health during travel and in the days and weeks after travel. If you develop a fever or serious illness, contact your healthcare provider immediately and be sure to mention your recent travels.

Read the CDC’s travel alert for Japan »

Read the CDC’s travel alert for Poland »

Learn more about the MMR vaccine, which prevents measles, mumps and rubella »


Probiotics,neurologic damage and vaccines

Q. My child has autism and I have read that giving probiotics before vaccines will help protect him from further neurologic damage caused by vaccines. Is this true?

A.Your question is most easily addressed in two parts:

Neurologic damage and vaccines

Vaccines have not been found to damage the neurologic systems of children with or without autism, so parents of children with autism can take comfort in these findings. 

Use of probiotics

Probiotics are a type of bacteria that typically reside in the digestive tract where they help with digestion and might provide protection from disease-causing bacteria. Because some children with autism experience gastrointestinal issues, parents sometimes wonder about giving probiotics. Our best evidence related to the use of probiotics is from studies of children who recently took oral antibiotics. Because antibiotics kill indiscriminately, some doctors and scientists wondered whether giving probiotics would help restore the normal bacterial environment in the intestine after use of antibiotics. To date, the data do not strongly support this.

While some evidence exists that it may work, a review of studies related to this topic (published in the Journal of the American Medical Association [JAMA] in May 2012) found that many of the studies supporting this notion were poorly designed. Further, most of the studies did not consider or comment on the known negative effects related to the use of probiotics, such as bloodstream infections or endocarditis.

Read a summary of the study in Pediatric News»

Read the study published in JAMA»


Vaccines for traveling abroad

Q. My son is traveling abroad for a school trip. How can I find out if he needs any vaccines?

A. Depending on your son’s destination, he may need to receive vaccines or travel medications prior to leaving. Typically, routine vaccinations, such as Tdap, MMR, polio, hepatitis A, hepatitis B, chickenpox, pneumococcus, Haemophilus influenzae type b (Hib), meningococcus and influenza should be up to date before traveling. In addition, you should consider taking your son to a travel clinic well in advance of the trip, so any additional vaccines or travel needs can be addressed.

Find a travel clinic near you »

Learn more about the vaccines mentioned »

Learn more about vaccines for travelers »


Hepatitis B vaccine and newborns

Q. Why does my baby need to get a dose of hepatitis B vaccine shortly after birth if I know that I’m not infected with the virus? 

A. Although many babies infected with hepatitis B are exposed while passing through the birth canal of an infected mother, some can become infected through exposure to small quantities of blood from an infected person, such as on a toothbrush, washcloth or razor. Because the quantities of blood capable of transmitting the virus can be miniscule and because many children do not suffer symptoms of infection, children can be unknowingly infected. In fact, before the hepatitis B vaccine was routinely recommended, about 16,000 children less than 10 years of age were infected with the virus every year. If infected with hepatitis B, children are more likely to suffer long-term infection, liver damage and liver cancer. Because many people do not know they are infected, it’s difficult to protect children from every situation that may expose them to the virus. For these reasons, babies are given three dose of hepatitis B vaccine, with the first dose given shortly after birth.

Learn more about the hepatitis B vaccine »


Two-month well-child visit and vaccines

Q. My baby is going for her two-month well visit in a few weeks. What vaccines will be given and how can I prepare for the upcoming visit?

A. During your baby’s two-month well-child visit, she will likely receive vaccines to prevent diphtheria, tetanus, pertussis, Haemophilus influenzae type b, rotavirus, pneumococcus, polio and hepatitis B. While this seems like a lot of shots, several of these may be offered as combination vaccines and the rotavirus vaccine is given orally.

You’re already getting prepared by finding out what to expect and learning about the vaccines and diseases they prevent. If you need additional information, check the “A Look at Each Vaccine" pages on our websites.

You should write down any questions you have for the doctor. If you are comfortable with your decision, your baby will respond to your mood and be more relaxed. You can also help your baby by bringing her favorite toy or blanket to the appointment. Some moms also find that holding or feeding the baby during shots helps the baby be more comfortable.

Learn more about preparing yourself and your baby for vaccines»

Learn more about vaccines due at other well visits»


Multiple doses of vaccines

Q. Why are multiple doses of vaccines necessary?

A. Vaccines can require multiple doses for a number of reasons. First, certain types of vaccines, such as those made with purified proteins or inactivated toxoids, provide more complete protection after a person receives more than one dose. Second, immune responses sometimes weaken, so additional doses may be necessary so that people can respond readily to invading viruses and bacteria.

Learn more about why some vaccines require multiple doses »


Newborns and unvaccinated children

Q. My friend is not having her children immunized. I am going to be having a baby soon. Is it safe to allow my baby to be around them?

A. Any time your baby is around other people, he or she could be exposed to viruses or bacteria. Because your friend’s children are not immunized, they will be more susceptible to the dangerous childhood illnesses that are commonly kept at bay because of high levels of immunization. Therefore, you may want to limit your baby’s exposure to these children, especially if they are ill.

As your baby is immunized, he or she will be less likely to get the diseases against which she was vaccinated. However, because vaccines don’t always afford complete protection, it will still be important to remain vigilant.


HPV Q&A page

In recognition of “Cervical Cancer Awareness” month, this edition of “Ask the VEC” features the question and answer page from our Prevent HPV campaign.

Go to to ask a question or see what others are asking about HPV and the vaccine.



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