Tag: rotavirus

How Much Shedding Would a Vaccine Shed…

Are you still confused about vaccine shedding?

You should be worried about wild diseases, not shedding from vaccines.
You should be worried about wild diseases, not shedding from vaccines.

As this infographic describes, it really isn’t that complicated…

What Does Vaccine Shedding Really Mean?

To clear up some things:

  • yes, some vaccines do actually shed, but it is rarely a reason to avoid getting vaccinated and protected
  • of the vaccines that we use routinely, shedding is limited to the rotavirus vaccines, FluMist, and the chickenpox vaccines
  • some other vaccines that can shed include the oral polio vaccine and the smallpox vaccine
  • the rubella component of MMR may very rarely shed, but only in breastmilk

If vaccines do shed, why shouldn’t we be more concerned about it?

Well, for one thing, most vaccines don’t shed.

DTaP, hepatitis A, hepatitis B, Hib, flu, IPV, HPV, meningococcal, pneumococcal, and Tdap shots – none of them shed.

And then there is the fact that:

  • when a vaccine sheds, it is the weakened or attenuated vaccine strain, not the wild strain that would cause more serious disease. Putting it another way, if the vaccine strain doesn’t make the person who is getting immunized sick, then why would it get someone else sick if they got it through shedding? Of course, there is a situation in which even a vaccine strain could be dangerous, and that’s for those who are severely immunosuppressed. Still, natural disease would be bad for these kids too!
  • even with oral polio vaccines, the problem isn’t really shedding, which actually provides a type of passive immunization in areas where polio is still not well controlled. The problem is that very rarely, the attenuated virus in the oral polio vaccine can revert to a form that can cause the person who was vaccinated to actually develop polio (VAPP). Now, shedding of this strain would be a problem, but only if the other person wasn’t immune.
  • rotavirus vaccines only shed in stool. You can avoid it by washing your hands when you change your child’s diapers, which you hopefully do anyway.
  • FluMist is attenuated and cold-adapted, which means that it won’t replicate well in our warmer nasal passages and respiratory tracts.
  • you have to actually get a rash, which is rare, for the chickenpox vaccine to shed.
  • it is only kids with eczema that usually get sick if they are exposed to someone who recently had the smallpox vaccine. Since the smallpox vaccine causes skin reactions, even the attenuated vaccine strain can cause severe reactions if a child’s skin is already broken down, like with eczema.

Are you still concerned about shedding?

Can a Vaccinated Person Transmit Measles Through Shedding?

To put your mind at ease, understand that you are not going to get measles from shedding.

“In this systematic review, we have determined that there have been no confirmed cases of human-to-human transmission of the measles vaccine virus.”

Greenwood et al on A systematic review of human-to-human transmission of measles vaccine virus

Well, at least not from someone who was recently vaccinated shedding a vaccine-strain of measles

If you aren’t vaccinated and protected, you could easily get it from someone who has measles and who is shedding the wild type virus though. Measles is so contagious, you just have to be in the same room as someone with measles and you will likely get sick. In fact, you can enter a room a few hours after they have left and sill catch measles!

And in theory, if someone developed vaccine-associated measles – they got sick with a vaccine-strain of measles after getting vaccinated – then they could spread the virus to someone who wasn’t immune. That’s just because they would be contagious though, not anything specific to vaccines and shedding. Also, it is basically unheard of for this to happen.

Dectecting vaccine strain measles in urine isn't something to be concerned about because it can't lead to an infection. Measles is spread through respiratory secretions, not urine.
Dectecting vaccine strain measles in urine isn’t something to be concerned about because it can’t lead to an infection. Measles is spread through respiratory secretions, not urine.

What about all of those folks who test positive for vaccine-strain measles during an outbreak?

That’s not about shedding either.

They aren’t even people with measles. Instead, they typically have a vaccine reaction, a rash and/or fever after getting their MMR and they test positive for the vaccine strain of measles because they just got a live virus vaccine.

Is Vaccine Shedding a Threat?

Shedding isn’t the threat that anti-vaccine folks make it out to me.

Think about it. If it really was a big problem, then why don’t more intentionally unvaccinated kids with exemptions get sick when they are around kids who are vaccinated?

“Health officials should require a two-week quarantine of all children and adults who receive vaccinations. This is the minimum amount of time required to prevent transmission of infectious diseases to the rest of the population, including individuals who have been previously vaccinated.”

Sally Fallon Morell, president of the Weston A. Price Foundation

We don’t actually quarantine anyone after they are vaccinated, so why don’t more kids with immune system problems get sick via shedding?

Or just think about what happens in a typical daycare or school. All of the kids don’t get vaccinated on the same day, so if shedding was an issue, wouldn’t the kids who had gotten their vaccines first shed on the ones who weren’t yet vaccinated, getting them sick?

Of course, this doesn’t happen. Again, shedding isn’t the threat that anti-vaccine folks make it out to be.

More on Vaccine Shedding

Can I Get Rotavirus from My Recently Vaccinated Baby?

Your two month old recently got her vaccines, including the rotavirus vaccine.

Shedding Season is not a real thing.
Shedding Season is not a real thing.

Now you have diarrhea.

Was it from shedding from your child’s rotavirus vaccine?

Does the Rotavirus Vaccine Shed?

Like some other live virus vaccines, it is well known that the rotavirus vaccine can shed.

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.

More on Shedding and Rotavirus Vaccines

Do You Know What Vaccine-Preventable Diseases Look Like?

Odds are that you have never seen anyone with smallpox, but what about measles or mumps?

No?

Have you ever even seen someone with chicken pox?

Photos of Vaccine-Preventable Disease

Maybe if more folks knew what typical vaccine-preventable diseases looked like, then they wouldn’t be so quick to think about skipping or delaying their kids vaccines.

And they certainly wouldn’t think that these are mild diseases that they wanted their kids to get, thinking natural immunity would be better than the immunity that they could more easily and safely get from a vaccine.

Severe dehydration in a child with a rotavirus infection.
Severe dehydration in a child with a rotavirus infection.

Kids with diphtheria develop a bull neck and a thick pseudomembrane that covers their throat.
Kids with diphtheria develop a bull neck and a thick pseudomembrane that covers their throat. Photo by the Japanese Society of Tropical Medicine

Can an unvaccinated child really get tetanus after a toe nail injury?
Can an unvaccinated child really get tetanus after a toe nail injury? Photo by Petrus Rudolf de Jong (CC BY 3.0)

Newborns and infants have the highest rates of death from pertussis.
Newborns and infants have the highest rates of death from pertussis or whooping cough.

An infant with measles during the 2014 outbreaks in the Philippines.
An infant with measles during the 2014 outbreaks in the Philippines. Photo by Jim Goodson, M.P.H.

Mumps causes kids to have fever, puffy cheeks, and a painful, swollen jaw.
Mumps causes kids to have fever, puffy cheeks, and a painful, swollen jaw.

A baby with a congenital cataract and blueberry muffin rash - classic signs of congenital rubella syndrome.
A baby with a congenital cataract and blueberry muffin rash – classic signs of congenital rubella syndrome. (CC BY-NC-SA)

In addition to respiratory problems (think iron lungs), polio causes muscle atrophy.
In addition to respiratory problems (think iron lungs), polio causes muscle atrophy. (CC BY-NC 4.0)

This 2016 hepatitis A outbreak linked to frozen strawberries led to 143 cases and 56 hospitalizations.
This 2016 hepatitis A outbreak linked to frozen strawberries led to 143 cases and 56 hospitalizations.

Chronic hepatitis B is a silent killer.
Chronic hepatitis B is a silent killer.

A papilloma caused by HPV on the vocal cords of a child with recurrent respiratory papillomatosis.
A papilloma caused by HPV on the vocal cords of a child with recurrent respiratory papillomatosis. (CC BY 4.0)

Even if they survive, kids can lose fingers, toes, or even arms and legs to meningococcemia.
Even if they survive, kids can lose fingers, toes, or even arms and legs to meningococcal disease.

In addition to pneumonia and meningitis, the Hib bacteria can cause epiglottitis, making it very difficult to breath.
In addition to pneumonia and meningitis, the Hib bacteria can cause epiglottitis, making it very difficult to breath. Seen here are the ‘thumb sign’ on X-ray and the cherry red epiglottis.

Before wide use of the Hib and Prevnar vaccines, infants with fever would routinely get spinal taps and you would hope for clear fluid (cloudy fluid could be a sign of a bacterial infection).
Before wide use of the pneumococcal vaccines, infants with fever would routinely a get spinal tap to make sure that they didn’t have bacterial meningitis.

If a mother get chicken pox late in her pregnancy, her baby will be exposed before he is born and will develop chicken pox, often severe, in his first week of life.
If a mother get chicken pox late in her pregnancy, then her baby will be exposed before he is born and will develop chicken pox, often severe, in his first week of life. (CC by 3.0)

Although rare, even infants can develop shingles, most commonly if their mothers had a chicken pox infection while pregnant.
Although rare, even infants can develop shingles, most commonly if their mothers had a chicken pox infection while pregnant. (CC by 3.0)

Never touch a bat that you find on the ground during the day, as it might have rabies.
Animals acting strangely may have rabies. Photo by Radu Privantu (CC BY 2.0)

As in most years, flu deaths in children mostly occurred in kids who weren't vaccinated.
As in most years, flu deaths in children mostly occurred in kids who weren’t vaccinated.

Two kids with smallpox - one vaccinated and one unvaccinated. Can you guess which is which?
Two kids with smallpox – one vaccinated and one unvaccinated. Can you guess which is which?

Surprisingly, treatments haven't changed much since this photo was taken of a patient with yellow fever in 1898.
Surprisingly, treatments haven’t changed much since this photo was taken of a patient with yellow fever in 1898.

Mary Mallon (Typhoid Mary) was quarantined because she continued to work as a cook, spreading Salmonella typhi bacteria to other people.
Mary Mallon (Typhoid Mary) was quarantined because she continued to work as a cook, spreading Salmonella Typhi bacteria to other people.

Japanese encephalitis is spread by mosquito bites.
Japanese encephalitis is spread by mosquito bites.

I know what some of you are thinking. And no, just because these vaccine-preventable diseases aren’t as common as they used to be doesn’t mean that any of these vaccines aren’t necessary.

Why not?

We don’t see them as much as we did in the pre-vaccine era simply because these vaccines work!

“I also warn them not to share their fears with their neighbors, because if too many people avoid the MMR, we’ll likely see the diseases increase significantly.”

Dr. Bob Sears in The Vaccine Book

We all know what happens if we stop vaccinating.

And it is not just that we get a few updated photos of kids with measles, mumps, diphtheria, and other vaccine-preventable diseases…

More on Photos of Vaccine-Preventable Diseases

 

Why Can’t My 9-Month-Old Get the Rotavirus Vaccine?

The rotavirus vaccines are typically given when infants are two to six months old.

The first dose can be given as early as 6 weeks or as late as 15 weeks though.

The rotavirus vaccines are given between 6 weeks to 32 weeks.

And the final dose can be given as late 8 months (32 weeks).

Why Can’t My 9-Month-Old Get the Rotavirus Vaccine?

What happens if your child didn’t get their rotavirus vaccine on time?

While these vaccines are usually given on either a two and four month (Rotarix) or two, four, and six month (RotaTeq) schedule, as you can see above, there is some flexibility in that timing.

Still, the first dose of the rotavirus vaccine can’t be given any later than 15 weeks and the final dose can’t be given any later than 8 months though, so there is no way that a nine-month-old would be able to get vaccinated.

What would happen if your child did?

“Vaccination should not be initiated for infants aged 15 weeks and 0 days or older because of insufficient data on safety of dose 1 of rotavirus vaccine in older infants. The minimum interval between doses of rotavirus vaccine is 4 weeks; no maximum interval is set. All doses should be administered by age 8 months and 0 days.”

Prevention of Rotavirus Gastroenteritis Among Infants and Children Recommendations of the Advisory Committee on Immunization Practices

The rotavirus vaccines are only licensed at these specific ages, so were not studied in older infants and toddlers. If your 9-month-old did receive a rotavirus vaccine, it would be considered a vaccination error and should be reported.

So why not study them in older kids?

Since severe rotavirus infections mostly occur in younger children between the ages of 4 and 23 months, it doesn’t make any sense to wait until they are older to get them vaccinated.

“To minimize potential risk of intussusception, the World Health Organization (WHO) recommends that rotavirus immunization should be initiated by age 15 weeks and completed before age 32 weeks.”

Age restrictions for rotavirus vaccination: evidence-based analysis of rotavirus mortality reduction versus risk of fatal intussusception by mortality stratum

Also, although the risk is low, a small risk of intussusception after getting the rotavirus vaccine is thought to increase with increasing age of the first dose.

What does all of this mean?

It means that you should follow the immunization schedule and get your kids vaccinated and protected on time.

What to Know About Rotavirus Vaccine Timing

Don’t delay getting your child’s rotavirus vaccine or you may not be able to get it at all, as unlike most other vaccines, these vaccines have strict upper limits for when they can be given.

More on Rotavirus Vaccine Timing