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Patient education: Vaccines for infants and children age 0 to 6 years (Beyond the Basics)

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Jan E Drutz, MD
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Teresa K Duryea, MD
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Mary M Torchia, MD
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INTRODUCTION

In the United States, routine vaccines are recommended in children between ages 0 and 6 years to prevent a number of serious or even deadly diseases. The recommended schedule is available through the Centers for Disease Control and Prevention.

This article will review the recommended timing and dose of these vaccines, possible side effects, and vaccine effectiveness in children between ages 0 and 6 years.

How vaccines work, the risks and benefits of vaccines, common concerns regarding vaccine safety, vaccines recommended for children 7 to 18 years, vaccines for adults, and vaccines for travel are presented separately. (See "Patient education: Why does my child need vaccines? (Beyond the Basics)" and "Patient education: Vaccines for children age 7 to 18 years (Beyond the Basics)" and "Patient education: Adult vaccines (Beyond the Basics)" and "Patient education: Vaccines for travel (The Basics)".)

HEPATITIS B

Inflammation of the liver (hepatitis) can be caused by autoimmune diseases, parasites, toxic drugs, chemical agents, and certain viral infections, including hepatitis B virus (HBV). Although the hepatitis B virus infection often resolves or causes no symptoms, HBV can cause chronic liver disease that leads to progressive liver scarring (cirrhosis) or liver cancer. HBV is transmitted by contact with an infected individual's body fluids, such as during unprotected sexual intercourse, by sharing contaminated needles, or from contact with contaminated blood or blood products. In addition, HBV can be transmitted from an infected pregnant woman to her baby. (See "Patient education: Hepatitis B (Beyond the Basics)".)

Although most infants are not at high risk for becoming infected with HBV, immunizing during infancy is the most effective way to ensure lifetime protection.

Timing and dose — HBV vaccination is recommended for all children beginning at birth. The series also can be started at a later time. The vaccine requires three doses, with the first usually given a day or two after birth. The second and third doses are given one to two months later and then at 6 to 18 months of age.

Hepatitis B vaccine precautions — HBV vaccination is not recommended for people with a severe allergy to baker's yeast. The vaccine can be given to people with a history of multiple sclerosis, Guillain-Barré syndrome, autoimmune disease, or other chronic disorders, as well as to pregnant women.

HepB vaccine effectiveness — When given according to the recommended schedule, the hepatitis B (HepB) vaccine protects 98 to 100 percent of individuals from developing chronic hepatitis B infection.

DIPHTHERIA, TETANUS, PERTUSSIS

Diphtheria is a highly contagious disease. It is usually transmitted via droplet particles that are coughed or sneezed into the air. It can cause a thick covering in the back of the throat that can lead to breathing problems or heart failure.

Tetanus is another very serious infection that is caused by a bacterial toxin. The bacteria reside in soil and the intestinal tracts of certain mammals. It enters the body through an open wound, multiplies, and produces a toxin that can affect nerves controlling muscle activity. A common symptom of tetanus infection is stiffness of the jaw muscles ("lockjaw").

Pertussis, or whooping cough, is an upper respiratory illness caused by a bacterium. The organism is highly contagious, spreads easily and can cause serious illness, especially in infants.

Tetanus and diphtheria disease are rare in the United States because of the high numbers of people who have been immunized. However, the number of infants in the United States who are affected by pertussis is rising despite widespread vaccination. The good news is that infants who are immunized against pertussis disease are typically less ill than those who are not immunized.

Timing and dose — Combined diphtheria, tetanus, and acellular pertussis (DTaP) vaccine is recommended for all children in the United States. The acellular form of pertussis vaccine (DTaP) has replaced the older form of pertussis vaccine (DTP), known as the whole cell vaccine. A total of five separate doses are recommended, at 2, 4, and 6 months of age, with the fourth dose given at 15 to 18 months and the fifth at 4 to 6 years of age. The recommended schedule is available through the Centers for Disease Control and Prevention.

Adolescents should receive a booster dose of tetanus diphtheria pertussis vaccine at 11 to 12 years of age (called Tdap). Subsequent doses of diphtheria and tetanus vaccine (called Td) are recommended at 10-year intervals throughout life.

DTaP and DTP vaccine precautions — Common side effects include injection site pain, redness, and swelling; fever; drowsiness; and loss of appetite. These reactions are more common after the fourth and fifth doses.

Children who have a severe allergic reaction (anaphylaxis) or brain swelling within seven days of receiving the DTaP or DTP vaccine should not receive future doses of this vaccine.

If a child develops one of the following problems within 48 hours of receiving the diphtheria-tetanus-pertussis vaccine, the next vaccine should be given with caution.

Temperature ≥104.8ºF, not related to a known cause

Collapse or shock-like state

Persistent, inconsolable crying lasting three hours or longer

Seizure or convulsions within three days after the vaccine

In the event that one or more of these reactions occurs in an infant or young child, some experts recommend giving only the combination diphtheria-tetanus (DT) vaccine.

Parents should call their child's healthcare provider (for high fever or excessive crying) or emergency medical services (for collapse or seizures) if one or more of these reactions develop.

Children who develop other symptoms after receiving the vaccine, such as low-grade fever or irritability, should receive any subsequent dose(s) of the vaccine at the next recommended interval(s).

DTaP effectiveness — DTaP is a very effective vaccine that protects 80 to 85 percent from pertussis, 95 percent from diphtheria, and nearly 100 percent from tetanus. Because protection can fade over time, booster vaccines are needed at least every 10 years. (See 'Timing and dose' above.)

POLIOMYELITIS

During the first half of the 20th century, poliomyelitis was a major cause of serious illness and death throughout the world. It is still a significant health problem in some developing countries. Before a vaccine was available, more than 20,000 cases of polio were reported in the United States per year. The primary signs of polio include muscle weakness, pain, and fatigue; ultimately, the illness can lead to paralysis and even death.

All children should be vaccinated against polio to avoid new outbreaks. In the United States, the polio vaccine is made from a killed virus and is injected (called IPV). In other countries, where polio disease is still a major problem, oral polio vaccine (OPV) is given.

Timing and dose — The injected polio vaccine series in the United States includes four doses; the first and second doses are given at 2 and 4 months of age. The third dose is usually given at 6 to 18 months of age, and a fourth dose is routinely given at 4 to 6 years, before school entry. Children who miss a dose should be given the remaining doses.

Polio vaccine precautions — The injected polio vaccine should not be given to children who have a severe allergy to antibiotics contained in the vaccine, including neomycin, streptomycin, or polymyxin B. There is little to no risk of side effects (eg, swelling at injection site). There is no risk of developing poliomyelitis with the IPV vaccine currently used in the United States.

Polio vaccine effectiveness — When three doses of the polio vaccine are given, 99 percent of children develop immunity. Fortunately, even the one percent of children in the United States who do not develop immunity after being vaccinated are unlikely to develop polio. This is because of "herd immunity," meaning that most people who have been vaccinated against polio are immune, which protects even those who are not immune.

ROTAVIRUS

Rotavirus is the single most important cause of severe diarrhea and dehydration in infants and young children. A rotavirus vaccine is recommended for all infants in the United States. Two vaccines are available: RotaTeq (RV5) and Rotarix (RV1).

Timing and dose — The vaccine is in a liquid form and is given by mouth (not as a shot). The first dose of the vaccine should be given between 6 and 15 weeks of age, but not after 15 weeks. The number of doses (two or three) depends upon which vaccine is given:

RotaTeq (RV5) – Three doses of RV5 are recommended, given at 2, 4, and 6 months of age. The third dose of the vaccine should be given by 8 months of age.

Rotarix (RV1) – Two doses of RV1 are recommended, given at 2 and 4 months of age. The second dose should be given by 8 months of age.

Rotavirus vaccine precautions — Rotavirus vaccine should not be given to infants with a known immunodeficiency or history of intussusception. RV1 should not be given to infants with a history of latex allergy. In all infants, there is a small risk of diarrhea and vomiting in the week after the vaccine is given. Healthy infants with normal immunity can be given the rotavirus vaccine even if there is a sibling or other family member who does not have normal immunity, as long as the family practices good hand washing and proper hygiene, especially after changing the infant's diapers. If an infant develops abdominal pain, vomiting, diarrhea, blood in the stool, or has a change in bowel movements after receiving the rotavirus vaccine, the parents should contact their child's healthcare provider immediately.

Rotavirus vaccine effectiveness — Rotavirus vaccine does not prevent diarrhea or vomiting caused by other bacteria or viruses, but it is very effective in preventing diarrhea caused by rotavirus.

HAEMOPHILUS INFLUENZAE B (HiB)

Until the mid-1990s, Haemophilus influenzae serotype b (Hib) was the most common cause of bacterial meningitis (inflammation of the covering of the brain) in children. It was also responsible for other serious bacterial infections, including skin, throat, and joint infections. The widespread use of Hib vaccines in infancy has led to a dramatic decline in the incidence of invasive Hib disease in children. However, the disease remains common in countries that do not use the vaccine. Despite its name, Hib is not related to the influenza virus.

Timing and dose — There are several types of Hib vaccines available in the United States; one is given in three doses at 2, 4, and 6 months of age and as a booster dose at 12 to 15 months. The second type is given in two doses, at 2 and 4 months, and as a booster dose at 12 to 15 months of age. There are vaccines that combine the Hib vaccine with another vaccine or vaccines, including Hib/DTaP/inactivated poliovirus vaccine, and Hib/meningococcal vaccine.

Hib vaccine precautions — There are no medical conditions that require a child to avoid receiving Hib vaccine, other than a severe allergic reaction to one of the vaccine components. Reactions (eg, fever, irritability) are uncommon after Hib vaccine. Local reactions, consisting of pain, redness, and/or swelling at the injection site occur in approximately 25 percent of children. Such local reactions usually are mild and resolve within 24 hours.

Hib vaccine effectiveness — Hib vaccines protect 95 to 100 percent of children from developing a serious infection caused by Hib.

PNEUMOCOCCAL

Streptococcus pneumoniae (pneumococcus) can cause serious infections, including meningitis and pneumonia, which can be fatal in young children. This also is true in older children with a chronic medical condition or a weakened immune system.

Before infants were routinely immunized against pneumococcus in the United States, there were approximately 17,000 cases of invasive disease each year among children younger than 5 years of age, including 700 cases of meningitis and 200 deaths.

Timing and dose — Children should receive a total of four doses of pneumococcal vaccine. Doses should be given at 2, 4, and 6 months of age and 12 to 15 months of age. The first dose can be given as early as 6 weeks of age.

Pneumococcal vaccine precautions — The most common side effect of the vaccine is an injection site reaction (redness, pain) and fever. (See "Patient education: Fever in children (Beyond the Basics)".)

Pneumococcal vaccine effectiveness — Pneumococcal vaccine is more than 90 percent effective in preventing invasive illness.

INFLUENZA

Commonly known as flu, influenza is a highly contagious viral infection that occurs in outbreaks worldwide, usually during the winter months in the United States. Young children and those with certain underlying medical conditions are at increased risk for severe or complicated influenza infection. Immunizing all children (and adults) can help decrease this risk. The influenza vaccine does not prevent illnesses such as the common cold or strep throat. (See "Patient education: Influenza prevention (Beyond the Basics)".)

Immunization against influenza is recommended for all persons older than 6 months.

Timing and dose — There are two types of influenza vaccine; one is an injection (shot), while the other is administered as a nasal spray. In the United States, the nasal spray vaccine is not recommended for the 2016-2017 influenza season.

The shot is approved for adults and children 6 months of age and older, while the nasal spray is approved only for those between 24 months of age and 49 years of age.

The influenza viruses change every year, which means that a new vaccine must be given every year (in the fall). In the first year that a child (younger than 9 years old) gets the vaccine, two doses are recommended; the second dose is given at least one month after the first. In subsequent years, most children younger than 9 years will need only one dose, but some may need two doses.

Influenza vaccine precautions — Both forms of the influenza vaccine are prepared using chicken eggs. Thus, children who have had a severe allergic reaction to chicken or egg proteins should not get the vaccine. Talk to your child's doctor or nurse if you have a question about allergies and vaccines. (See "Allergic reactions to vaccines".)

Injectable influenza vaccine precautions — Children who have a fever (higher than 100.4ºF [38ºC]) should wait to get the vaccine until the fever resolves. However, children with mild illnesses that do not cause a fever can get the vaccine. The most common side effect of the shot is redness and soreness at the injection site. Some children develop a low-grade fever or a runny or congested nose after vaccination, particularly in children younger than 2 years. (See "Patient education: Fever in children (Beyond the Basics)".)

Nasal spray influenza vaccine precautions — In the United States, the nasal spray influenza vaccine is not recommended for the 2016-2017 influenza season. In other countries, the nasal spray vaccine is not recommended for children who take aspirin daily and those with a weakened immune system, Guillain-Barré syndrome, asthma, and other conditions (eg, chronic lung or heart problems, pregnancy, chronic metabolic disease, kidney dysfunction, and blood disorders). The nasal spray vaccine is not recommended for children younger than 24 months. It is also not recommended for contacts of people with a severely weakened immune system (ie, those who require hospitalization in a protected environment).

Influenza vaccine effectiveness — The injectable influenza vaccine protects between 70 and 90 percent of healthy children from developing laboratory-confirmed influenza infection. The nasal spray vaccine protects about 87 percent of children between ages 5 and 7 years.

MEASLES-MUMPS-RUBELLA (MMR)

Measles, mumps, and rubella are illnesses that may be transmitted by airborne droplets released during coughing or sneezing.

Measles (also known as rubeola) is a highly contagious viral illness of the respiratory tract that primarily affects children; it causes a distinctive rash, fever, and cough, and may result in complications, including infection of the middle ear, lungs, and brain.

Mumps is an acute, usually mild viral infection of childhood that causes painful swelling of the salivary glands. Mumps complications can develop, including inflammation of the brain (encephalitis), the protective membranes of the brain (meningitis) and, in males after puberty, swelling and tenderness of one or both testes (orchitis).

Rubella, also known as German measles, is a mild viral infection that causes fever, swelling of the lymph nodes in the neck, and a distinctive rash; however, it can cause severe birth defects (congenital rubella syndrome) if a woman becomes infected during early pregnancy.

The number of people affected by these diseases has fallen dramatically in the United States since vaccines were developed. Despite the rarity of these diseases in the United States, vaccination is still recommended for a number of reasons:

Individuals who visit or emigrate from countries that do not vaccinate against measles can spread the virus to those who are not immune.

Measles that develops during pregnancy can cause early labor and miscarriage.

The most serious complications of mumps occur more frequently in adults than children, including orchitis (leading to sterility in men), neurologic complications, and a risk of fetal death if the infection is acquired in early pregnancy.

Well-vaccinated groups of children help to protect almost everyone, including adults as well as other children.

Timing and dose — The first dose of MMR is administered at 12 to 15 months of age. A second dose is recommended routinely before school entry (between 4 and 6 years of age). The recommended schedule is available through the Centers for Disease Control and Prevention.

Children living in or traveling to areas where there is a measles outbreak (defined as ≥3 cases linked in time and space) and children traveling outside the United States should receive MMR vaccine earlier than it is routinely recommended.

MMR vaccine precautions — Common side effects of the MMR vaccine include a mild rash or fever; these may be seen one to two weeks after the vaccine is given, and usually lasts one to three days. (See "Patient education: Fever in children (Beyond the Basics)".)

Reasons to avoid the MMR vaccine include pregnancy, some immune system conditions, use of medications that weaken the immune system, cancer, or a severe allergy to gelatin or the antibiotic neomycin. The vaccine should be given later if a child has a serious illness or if the child has recently received a blood transfusion or other blood product (eg, serum immune globulin).

Concern has been raised about a possible link between the MMR vaccine, autism, autism spectrum disorder, and type 1 diabetes. To date, no scientific study published in the peer-reviewed literature has provided any evidence that such a link exists. (See "Patient education: Why does my child need vaccines? (Beyond the Basics)".)

For the first dose, the risk of febrile seizures is twice as high in children 12 to 23 months of age who receive MMR vaccine combined with varicella vaccine as in children who receive MMR vaccine and varicella vaccine separately. For this reason, separate MMR and varicella vaccines are generally preferred for the first dose if the child is younger than 48 months. The risk of febrile seizures decreases as children get older, so the combination MMR-varicella vaccine can be used for the second dose.

MMR vaccine effectiveness — When given on time, the MMR vaccine protects more than 99 percent of children from developing measles and 95 percent of children from developing mumps and rubella.

VARICELLA (CHICKENPOX)

Varicella is a highly contagious viral illness caused by infection with the varicella zoster virus (VZV). The disease causes fever, sore throat, and a distinctive, itchy rash with fluid-filled blisters that later forms scabs. The virus is transmitted by the spread of airborne droplets or direct contact with skin lesions. Complications of chickenpox may include bacterial infections of the skin, pneumonia, or, less commonly, inflammation of the brain. (See "Patient education: Chickenpox prevention and treatment (Beyond the Basics)".)

Before the vaccine was available, an estimated 3.7 million cases of chickenpox occurred in the United States every year, resulting in nearly 9000 hospitalizations and approximately 100 deaths.

Timing and dose — In the United States, VZV vaccine is recommended for all children at 12 to 18 months of age. The recommended schedule is available through the Centers for Disease Control and Prevention. A second dose is recommended at 4 to 6 years of age. A combination measles, mumps, rubella, and varicella vaccine (MMRV, ProQuad) may be used in children between 12 months and 12 years. However, as noted above, it is recommended that MMRV not be used for the first dose of MMR and varicella in younger than 48 months. Instead, individual administration of those vaccines should be given at separate injection sites. The VZV vaccine is not needed if a child develops typical chickenpox disease before the vaccine is given.

Chickenpox vaccine precautions — The varicella vaccine contains a live weakened form of VZV, thus it is not recommended for children with a weakened immune system or in someone experiencing moderate to severe illness. The vaccine should be delayed in a child who has recently received an injection of immunoglobulin, a blood transfusion, or other blood product. The vaccine is not recommended for children who have a severe allergy to neomycin or gelatin. The most common side effects of the VZV vaccine are redness or soreness at the injection site and a mild rash (about five spots).

For the first dose risk of febrile seizures is twice as high in children 12 to 23 months of age who receive VZV vaccine combined with measles-mumps-rubella (MMR) vaccine as in children who receive VZV vaccine and MMR vaccine separately. For this reason, separate VZV and MMR vaccines are generally preferred for the first dose if the child is younger than 48 months. The risk of febrile seizures decreases as children get older, so the combination MMR-VZV vaccine can be used for the second dose.

Chickenpox vaccine effectiveness — The chickenpox vaccine protects 70 to 90 percent of people who receive it. However, about 1 percent of people who are given the vaccine develop chickenpox; in these people, the infection is usually mild, fever does not usually occur, and skin blisters do not develop.

HEPATITIS A VACCINE

Hepatitis due to infection with the hepatitis A virus (HAV) is one of the most common viral infections in children and adolescents in the United States. HAV infection often causes few or no symptoms in younger children. By contrast, infection in adults can vary in severity from a mild flu-like illness to rapidly progressive, severe liver disease. Vaccinating children can help to protect adult caregivers from a potentially serious illness. (See "Patient education: Hepatitis A (Beyond the Basics)".)

HAV is found in the stool of infected individuals. A person can become infected with HAV by consuming contaminated food or water or by touching the mouth, nose, or eyes after touching a contaminated surface (eg, in the bathroom or during a diaper change). Washing the hands can help to prevent infection.

Timing and dose — The Hepatitis A (HepA) vaccine is recommended for all children between 12 and 23 months of age. Older children and adults also should consider being immunized. In all age groups, two doses are required, given at least six months apart

The vaccine also is recommended for certain high-risk adults, such as food handlers, international travelers, people with blood clotting disorders or chronic liver disease and those who live in communities with a high hepatitis A infection rate.

Hepatitis A vaccine precautions — The HepA vaccine should not be given if the child had a severe reaction to the vaccine after the first dose. The vaccine contains alum and phenoxyethanol, and should not be given to children with a known sensitivity to these additives. The most common side effect of the HepA vaccine is brief redness or discomfort at the injection site.

Hepatitis A vaccine effectiveness — The HepA vaccine protects nearly 100 percent of children who receive the recommended two doses.

WHERE TO GET MORE INFORMATION

Your child's healthcare provider is the best source of information for questions and concerns related to your child's medical problem.

This article will be updated as needed on our web site (www.uptodate.com/patients). Related topics for patients, as well as selected articles written for healthcare professionals, are also available. Some of the most relevant are listed below.

Patient level information — UpToDate offers two types of patient education materials.

The Basics — The Basics patient education pieces answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials.

Patient education: Vaccines for babies and children age 0 to 6 years (The Basics)
Patient education: Vaccines (The Basics)
Patient education: Meningitis in children (The Basics)
Patient education: Vaccines for children age 7 to 18 years (The Basics)
Patient education: Vaccines for travel (The Basics)
Patient education: Vaccines for adults (The Basics)
Patient education: Whooping cough (The Basics)
Patient education: Sickle cell disease (The Basics)
Patient education: Parotitis (The Basics)
Patient education: Mumps (The Basics)
Patient education: Hemophilia (The Basics)
Patient education: Poliomyelitis (The Basics)
Patient education: Measles (The Basics)
Patient education: Tdap vaccine (The Basics)
Patient education: When your child has sickle cell disease (The Basics)

Beyond the Basics — Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are best for patients who want in-depth information and are comfortable with some medical jargon.

Patient education: Why does my child need vaccines? (Beyond the Basics)
Patient education: Vaccines for children age 7 to 18 years (Beyond the Basics)
Patient education: Adult vaccines (Beyond the Basics)
Patient education: Hepatitis B (Beyond the Basics)
Patient education: Fever in children (Beyond the Basics)
Patient education: Influenza prevention (Beyond the Basics)
Patient education: Chickenpox prevention and treatment (Beyond the Basics)
Patient education: Hepatitis A (Beyond the Basics)
Patient education: Vaccines for travel (The Basics)

Professional level information — Professional level articles are designed to keep doctors and other health professionals up-to-date on the latest medical findings. These articles are thorough, long, and complex, and they contain multiple references to the research on which they are based. Professional level articles are best for people who are comfortable with a lot of medical terminology and who want to read the same materials their doctors are reading.

Allergic reactions to vaccines
Clinical trials of human papillomavirus vaccines
Mumps
Hepatitis A virus infection: Prevention
Hepatitis B virus vaccination
Meningococcal vaccines
Pneumococcal (Streptococcus pneumoniae) conjugate vaccines in children
Poliovirus vaccination
Vaccination for the prevention chickenpox (primary varicella infection)
Recommendations for the use of human papillomavirus vaccines
Rubella
Seasonal influenza in children: Prevention with vaccines
Standard immunizations for children and adolescents
Treatment of varicella (chickenpox) infection
Vaccinia virus as the smallpox vaccine

The following organizations also provide reliable health information.

National Library of Medicine

(www.nlm.nih.gov/medlineplus/healthtopics.html)

National Institute of Allergy and Infectious Diseases

(www.niaid.nih.gov)

Centers for Disease Control and Prevention (CDC) National Immunization Program

Toll-free: (800) 311-3435

(www.cdc.gov/vaccines)

National Foundation for Infectious Diseases

Tel: (301) 656-0003

(www.nfid.org)

The Children's Hospital of Philadelphia Vaccine Education Center

(www.chop.edu/service/vaccine-education-center/home.html)

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Literature review current through: Nov 2016. | This topic last updated: Wed Jul 27 00:00:00 GMT+00:00 2016.
The content on the UpToDate website is not intended nor recommended as a substitute for medical advice, diagnosis, or treatment. Always seek the advice of your own physician or other qualified health care professional regarding any medical questions or conditions. The use of this website is governed by the UpToDate Terms of Use ©2016 UpToDate, Inc.
References
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  1. Robinson CL, Advisory Committee on Immunization Practices (ACIP), ACIP Child/Adolescent Immunization Work Group. Advisory Committee on Immunization Practices Recommended Immunization Schedules for Persons Aged 0 Through 18 Years--United States, 2016. MMWR Morb Mortal Wkly Rep 2016; 65:86.
  2. Sugerman DE, Barskey AE, Delea MG, et al. Measles outbreak in a highly vaccinated population, San Diego, 2008: role of the intentionally undervaccinated. Pediatrics 2010; 125:747.
  3. Glanz JM, McClure DL, Magid DJ, et al. Parental refusal of pertussis vaccination is associated with an increased risk of pertussis infection in children. Pediatrics 2009; 123:1446.
  4. Centers for Disease Control and Prevention. Vaccine safety. Thimerosal. http://www.cdc.gov/vaccinesafety/concerns/thimerosal (Accessed on January 12, 2012).
  5. Centers for Disease Control and Prevention. Epidemiology and Prevention of Vaccine-Preventable Diseases. The Pink Book: Course Textbook, 13th ed, Hamborsky J, Kroger A, Wolfe S, (Eds). Public Health Foundation, Washington, DC 2015 http://www.cdc.gov/vaccines/pubs/pinkbook/index.html (Accessed on July 09, 2015).

All topics are updated as new information becomes available. Our peer review process typically takes one to six weeks depending on the issue.