What immunizations are recommended for a 4-year-old, including Diphtheria, Tetanus, and Pertussis (DTaP) vaccine, Measles, Mumps, and Rubella (MMR) vaccine, and Varicella vaccine?

Recommended Immunizations for 4-Year-Olds

A 4-year-old child should receive the fifth dose of DTaP vaccine, the fourth dose of IPV (inactivated poliovirus vaccine), the second dose of MMR vaccine, and the second dose of varicella vaccine, all of which can be administered simultaneously at this visit. 1

Core Vaccines Due at Age 4-6 Years

DTaP (Diphtheria, Tetanus, and Pertussis)

• Administer the final (fifth) dose of DTaP at age 4-6 years, completing the childhood series 1
• This dose should be given at least 6 months after the fourth dose 1
• The fifth dose provides critical booster protection, with vaccine effectiveness of 98.1% within the first year after administration 1

Inactivated Poliovirus Vaccine (IPV)

• Give the fourth and final dose of IPV at age 4-6 years 1, 2
• This completes the childhood polio vaccination series 1
• Can be administered as a combination vaccine (DTaP-IPV) to reduce the number of injections 1

MMR (Measles, Mumps, and Rubella)

• Administer the second dose of MMR at age 4-6 years 1
• This dose may be given earlier than age 4-6 years if desired, provided at least 4 weeks (28 days) have elapsed since the first dose 1
• All children achieve seroprotective antibody levels for measles, mumps, and rubella after this second dose 1

Varicella Vaccine

• Give the second dose of varicella vaccine at age 4-6 years 1
• This dose can be administered earlier if needed, provided 3 months have elapsed since the first dose (though a dose given at ≥28 days does not need to be repeated) 1
• The second dose significantly boosts immunity against chickenpox 2

Practical Administration Considerations

Combination Vaccines

• DTaP-IPV combination vaccines (Kinrix or Quadracel) are FDA-approved and preferred to reduce the number of injections from four to three 1
• Kinrix is specifically licensed for children aged 4-6 years as the fifth DTaP dose and fourth IPV dose 1
• These combination vaccines have comparable safety and immunogenicity to separately administered vaccines 1

Simultaneous Administration

• All four vaccines (DTaP, IPV, MMR, and varicella) can and should be administered during the same visit 1, 3, 4, 5
• Co-administration does not interfere with immune responses to any of the vaccine antigens 1, 3, 4, 5
• Studies demonstrate that DTaP-IPV given with MMR and varicella vaccines maintains excellent immunogenicity for all components 3, 4, 5
• Administer vaccines at different anatomic sites when giving multiple injections 1

Additional Vaccine to Consider

Influenza Vaccine

• Annual influenza vaccination is recommended for all children aged 6 months and older 1, 2
• Children under 9 years who have received fewer than two lifetime doses of influenza vaccine need two doses given at least 4 weeks apart 2
• This can be administered at the same visit as the other vaccines 3

Important Clinical Caveats

Vaccine Interchangeability

• Whenever feasible, use the same manufacturer's DTaP vaccine throughout the series, but vaccination should never be delayed if the previous manufacturer is unknown or unavailable 1
• If DTaP-IPV combination vaccine is inadvertently given earlier in the series, count it as valid if minimum intervals were met 1

Safety Profile

• The most common adverse events are injection-site pain and fever 5, 6
• Solicited local reactions at the DTaP-IPV injection site and general adverse events are similar whether vaccines are given separately or as combinations 3, 4
• No vaccine-related serious adverse events have been reported with this vaccination schedule 3, 4

Timing Flexibility

• While the recommended age is 4-6 years, these vaccines can be given as early as age 4 years if the child is unlikely to return for a later visit 1
• The final DTaP dose should not be given before age 4 years 1