Most parents likely don’t think about the minimum age or minimum intervals between vaccines, as they just get their kids vaccinated according to the routine immunization schedule.
Things don’t always go according to schedule though…
Recommended and Minimum Ages for Vaccines
After their birth dose of the hepatitis B vaccine, your baby’s next vaccines are usually at two months.
Can you get them earlier?
Yes. The minimum age for the first dose of rotavirus, DTaP, IPV, Hib, Prevnar, is 6 weeks.
Some other vaccines can be given earlier than their recommended age too, including:
- the first MMR vaccine, which can be given as early as age 6 months in certain high risk situations, like traveling out of the country or in an outbreak situation, although this dose will have to be repeated once the child is 12 months old
- the 4th dose of DTaP, which can be given as early as age 12 to 15 months, as long as at least 4 to 6 months have passed since the third dose
- the 2nd dose of Varivax, which may be given as early as 1 to 3 months after the first dose
- the Tdap vaccine, which can be given as early as age 7 years, instead of the more typical 11 to 12 years
- the HPV vaccine, which can be given as early as age 9 years, instead of the more typical 11 to 12 years
Why would you get a vaccine early?
What if you are going to be traveling just before you infant is going to be 2 months old? Or your 9 year old stepped on a rusty nail, and it had been just over 5 years since his last tetanus (DTaP) shot?
Recommended and Minimum Intervals for Vaccines
In addition to earlier ages, you can sometimes get vaccines more quickly, on an accelerated schedule.
For example:
- the minimum interval between the 1st and 2nd dose of rotavirus, DTaP, IPV, Hib, Prevnar is 4 weeks, instead of the standard 2 months
- the minimum interval between the 2nd and 3rd dose of rotavirus, DTaP, IPV, Hib, Prevnar is 4 weeks, instead of the standard 2 months
- the minimum interval between the 1st and 2nd dose of HPV is either 4 weeks (3 dose schedule) or 5 months (2 dose schedule)
- the minimum interval between the 2nd and 3rd dose of HPV is 12 weeks
- the minimum interval between the 1st and 3rd dose of HPV is 5 months, instead of the standard 6 months
Why give these vaccines more quickly than usual?
The usual reason is that a child is a little behind and is working to get caught up.
Absolute Minimum Ages for Vaccines
It is important to remember that in some cases, there are some hard and fast rules about minimum ages. That means that if you get these vaccines any earlier, they won’t count and you will likely have to repeat them, including getting :
- the 3rd dose of hepatitis B before 6 months (24 weeks) or sooner than 8 weeks after 2nd dose and 16 weeks after 1st dose
- the first dose of MMR, Varivax or hepatitis A before 12 months
- the 4th dose of Hib before 12 months
- the 4th dose of Prevnar before 12 months
- the 4th dose of DTaP before 12 months
- the 5th dose of DTaP before 4 years
- the 4th dose of IPV before 4 years
Sticking to the routine schedule helps to avoid vaccine errors, like giving a vaccine too early. In some situations, the 4 day grace period helps if a vaccine is given a little early.
More on Recommended and Minimum Ages and Intervals Between Doses of Vaccines
- CDC – Recommended and Minimum Ages and Intervals Between Doses of Routinely Recommended Vaccines
- CDC – General Principles for Vaccine Scheduling
- CDC – Catch-Up Immunization Schedule for Persons Aged 4 Months Through 18 Years Who Start Late or Who Are More Than 1 Month Behind
- Ask the Experts about Scheduling Vaccines
- Minimum Ages and Minimum Intervals Between Doses of Vaccines in a Series – Why Does It Matter?
- WHO – Table 3: Recommendations* for Interrupted or Delayed Routine Immunization – Summary of WHO Position Papers