Are you an adult that needs to get caught up because you have never been vaccinated, your parents skipped or delayed some vaccines, or you lost your immunization records?
What happens if you get a vaccine a few days too early?
You may even know about the minimum ages or minimum intervals between vaccines, but what happens if your child gets a vaccine just a few days early?
Is There a Grace Period for Getting Vaccines?
Fortunately, in most cases, getting a vaccine just a little early isn’t going to mean that the vaccine dose has to be repeated.
“Doses administered too close together or at too young an age can lead to a suboptimal immune response. However, administering a dose a few days earlier than the minimum interval or age is unlikely to have a substantially negative effect on the immune response to that dose. Known as the “grace period”, vaccine doses administered ≤4 days before the minimum interval or age are considered valid; however, local or state mandates might supersede this 4-day guideline.”
General Best Practice Guidelines for Immunization: Best Practices Guidance of the Advisory Committee on Immunization Practices (ACIP)
That’s because the Advisory Committee on Immunization Practices (ACIP) allows a 4-day grace period for most vaccines. So if your child got their vaccines 3 or 4 days before their 1st birthday, instead of on or after turning 12 months old, they would still count!
It is important to keep in mind that:
day 1 is the day before the day that marks the minimum age or minimum interval for a vaccine.
if a vaccine is given 5 or more days too early, beyond the grace period, then the interval to the next dose starts from the day that invalid dose was given. For example, if the second dose of Hib is given two weeks after the first dose (instead of the minimum 4 weeks), then you don’t repeat this invalid dose in two weeks (four weeks from the first dose), but instead wait an additional four weeks from the invalid second dose
live vaccines must be given at least 28 days apart if they are not given at the same time and the grace period can not be used to shorten this interval
Most importantly, in place since 2002, the grace period protects kids from having to repeat vaccines because of minor vaccine scheduling errors.
Like a few other vaccines, Gardasil underwent Fast Track approval by the FDA.
“This is the first vaccine licensed specifically to prevent cervical cancer. Its rapid approval underscores FDA’s commitment to help make safe and effective vaccines available as quickly as possible. Not only have vaccines dramatically reduced the toll of diseases in infants and children, like polio and measles, but they are playing an increasing role protecting and improving the lives of adolescents and adults.”
Jesse Goodman, MD, MPH, Director of FDA’s Center for Biologics Evaluation and Research
But that doesn’t mean that any corners were cut in getting it quickly approved or that the vaccine isn’t safe.
Vaccine Fast Tracking
The Fast Track process can help get new drugs and vaccines approved more quickly by the FDA because they have:
more frequent meetings with the FDA to discuss the drug’s development plan and to help ensure the collection of appropriate data needed to support drug approval
more frequent written communication from the FDA about such things as the design of the proposed clinical trials and the use of biomarkers
eligibility for Accelerated Approval and Priority Review, if relevant criteria are met
a Rolling Review, which means that a drug company can submit completed sections of its Biologic License Application (BLA) or New Drug Application (NDA) for review by FDA, rather than waiting until every section of the NDA is completed before the entire application can be reviewed. BLA or NDA review usually does not begin until the drug company has submitted the entire application to the FDA.
In very simple terms, it is kind of like having a VIP pass at an amusement park. It gets you a guide and helps you jump to the front of many of the lines, but you still don’t get to operate the rides yourself.
It is a myth that vaccine fast tracking means that a vaccine gets approved too fast.
They include Gardasil, Vaxchora, a cholera vaccine, the MenB vaccines, and FluBlock, the flu vaccine that is made in insect cells.
Others that have Fast Track designation include vaccines for anthrax (NuThrax anthrax vaccine adsorbed with CPG 7909 adjuvant), chikungunya, Clostridium difficile (Clostridium difficile toxoid vaccine), malaria, RSV, Zika, Ebola, Invasive Staphylococcus aureus infections in surgical populations, Shigella (Flexyn2a), and Lyme disease. None are approved yet though.
And that all of these vaccines have Fast Track designation is a good reminder that it isn’t a guarantee of approval.
“With Fast Track designation, early and frequent communication between the FDA and the biopharmaceutical company is encouraged throughout the entire drug development and review process to help to quickly resolve any questions or issues that arise, potentially leading to an earlier approval and access by patients.”
Encouraging Vaccine Innovation: Promoting the Development of Vaccines that Minimize the Burden of Infectious Diseases in the 21st Century
It just puts them on a Fast Track to get approved if they meet all of the FDA requirements for safety and efficacy.
The ability to develop and approve new vaccines quickly is also important as we continue to face new emerging disease threats. Faced with a deadly global pandemic, everyone will be glad that we have the ability to Fast Track vaccines and other drugs.
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…
When necessary, many vaccines can be given earlier and faster than the standard schedule.
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
And like with most other vaccines, this shedding isn’t usually a cause for concern and definitely isn’t a reason to think about skipping or delaying your child’s vaccines.
Why not?
“All members of the household should wash their hands after changing the diaper of an infant. This minimizes rotavirus transmission, for an undetermined number of weeks after vaccination, from an infant who received rotavirus vaccine.”
General Recommendations on Immunization Recommendations of the Advisory Committee on Immunization Practices (ACIP)
If you wash your hands when you change your child’s diapers after they have been vaccinated, just like you hopefully do anyway, you can avoid any possible contact with any rotavirus vaccine virus that might be shed in your child’s stool.
Can I Get Rotavirus from My Recently Vaccinated Baby?
But what would be the risk of your getting sick if you did come into contact with shedding rotavirus vaccine virus in your child’s diaper?
Would you be at risk to get sick?
Did your baby get sick after getting the actual vaccine?
That’s the thing about shedding that many people don’t understand. These live vaccines are made with attenuated or weakened strains of viruses, so they don’t typically get you sick when you are vaccinated. And they don’t typically get you sick when you are exposed through shedding. In fact, this shedding can sometimes help build herd immunity, as more people get exposed to the weakened strain of vaccine virus.
But can they get you sick?
Yes, if you have a problem with your immune system, which is why there are warnings about giving live vaccines to folks who are immunocompromised. And there used to be warnings about giving the oral polio vaccine to kids if they were around anyone with an immune system problem.
Vaccine viruses could also get you sick if they mutated from their attenuated state and became more virulent. Fortunately, that rarely happens with most vaccines.
“The theoretical risk of HRV and PRV shedding, transmission to, and infection of immunocompromised contacts is much lower than the real risk of wildtype rotavirus infection transmitted from unvaccinated children.”
Anderson on Rotavirus vaccines: viral shedding and risk of transmission
And most importantly, since kids are much more likely to shed virus after natural infections, it is much safer for everyone to get vaccinated and protected with these vaccines.
Surprisingly, even children with asymptomatic natural rotavirus infections can shed virus for several weeks, which is likely why these infections used to spread so easily or without known contacts.
Something that will likely surprise some folks even more is the news that just because someone gets diarrhea after being exposed to the rotavirus vaccine, either because they were vaccinated or through shedding, it doesn’t mean that the vaccine was the cause of the diarrhea!
“Of note, among all six AGE cases which possessed Rotarix-derived strains, four (sample No.1, 5, 6 and 7) were suspected to be caused by other pathogens. Most likely, the infants were infected with other pathogens during the shedding period of Rotarix strain.”
Kaneko et al on Identification of vaccine-derived rotavirus strains in children with acute gastroenteritis in Japan, 2012-2015
When vaccine strain rotavirus have been detected in kids with gastroenteritis, they often have other reasons to have diarrhea.
What does this all mean?
Don’t believe all of the hype anti-vaccine folks push about shedding from vaccines.
Do you have a scar on your arm and you aren’t sure why it is there?
Having a smallpox vaccine scar makes you a part of history.
Is it from the smallpox vaccine?
Recognizing Old Vaccine Scars
Classically, there are two vaccines that can leave a scar – the ones that protect us against smallpox and tuberculosis.
“BCG scar is a surrogate marker of vaccination and an important index in the vaccination program.”
Dhanawade et al on Scar formation and tuberculin conversion following BCG vaccination in infants: A prospective cohort study
And there are a few easy ways to tell if you have a smallpox scar.
When were you born? Remember, the smallpox vaccine hasn’t been used in the United States since the early 1970s and its use stopped everywhere in 1986.
And where were you born?
The BCG (bacille Calmette-Guerin) vaccine, on the other hand, is still in use in many countries, and is given at birth to prevent tuberculosis disease, including meningitis and disseminated tuberculosis. It isn’t routinely used in the United States though “because of the low risk of infection with Mycobacterium tuberculosis, the variable effectiveness of the vaccine against adult pulmonary TB, and the vaccine’s potential interference with tuberculin skin test reactivity.”
Do you have a vaccine scar on your arm? Photo by Earl Hershfield
In general though:
the BCG vaccine scar has a raised center
the smallpox vaccine scar is depressed, with lines that radiate to the edges
Complicating matters is the fact that you can have multiple scars from each vaccine…
“In 1972, the National Advisory Committee on Immunization in Canada recommended that routine immunization of infants for smallpox be stopped. Very few Canadians born after 1972 have been immunized against smallpox. Those, like me, who were immunized prior to that date have little or no immunity left. Nothing, but a small scar as testimony to a grand global achievement.”
Remember, shedding occurs when an infectious agent, typically a virus, can be found in urine, stool, or other bodily secretions. Shedding is not specific to vaccines though. Shedding occurs very commonly after natural infections too, which is one reason they are so hard to control.
So does the Flumist vaccine shed?
Yes, it does, and it isn’t a secret.
There is actually a warning about shedding and Flumist – to avoid contact with severely immunosuppressed persons (e.g., hematopoietic stem cell transplant recipients in a protected enviornment) for seven days after vaccination because of the theoretical risk that their severe immunosuppression might allow the weakened flu strain to somehow cause disease.
This warning obviously doesn’t apply to the great majority of people though.
And it shouldn’t be surprising that it sheds, after all, it is a live virus vaccine that is squirted in your nose!
Why isn’t it usually a problem?
Flumist contains attenuated viral strains of the flu that are temperature-sensitive, so even if you did get infected with the weakened flu strains from Flumist via shedding, they wouldn’t cause disease.
Another way to think about it is that the folks who actually get the Flumist vaccine don’t get the flu, so why would you get the flu if you were simply exposed to the vaccine virus by shedding?
Anti-vaccine folks are sharing this table like they uncovered some secret, but it is important to understand that shedding from the Flumist vaccine doesn’t cause disease. And this table is in package insert for Flumist!
The real concern with shedding is when it leads to folks actually getting sick.
Trying to scare folks about Flumist shedding is just like when they talk about the MMR vaccine, pushing the idea that the rubella vaccine virus might shed into breast milk or measles vaccine virus into urine. Either might happen, but since it won’t cause infection or disease, it certainly isn’t a reason to skip or delay your child’s vaccines.
What to Know About Shedding and Flumist
The Flumist vaccine does indeed shed, but unless you are going to have contact with someone who is severely immunocompromised in a protected enviornment, this type of shedding isn’t going to get anyone sick and isn’t a reason to avoid this vaccine.
