Tag: pregnancy

Did Your Hepatitis B Antibody Test Come Back Negative?

Hepatitis B can be prevented.Three doses of the hepatitis B vaccines have been shown to provide long lasting protection in most people.

Do you need to get your titers checked to make sure you are immune?

Usually not. Simply being fully vaccinated with the  vaccine is  good enough evidence that you are immune in most, but not all circumstances.

A few circumstances in which you might need to be tested can include:

  • a baby who was born to a HBsAg (hepatitis B surface antigen) mother
  • being a healthcare worker who has a job and who is in a work setting that puts them at higher risk for exposure to blood or body fluids from patients who are positive for HBsAg
  • being immunocompromised, so you are not sure if the vaccine is going to work, or patients requiring chronic dialysis
  • someone who has sex or shares needles with a person who has a chronic hepatitis B infection

The screening test for vaccine immunity that is done checks the persons level of anti-HBs (antibody to the hepatitis B surface antigen). It should be done one to two months after your last dose of hepatitis B vaccine, but not later.

“Persons determined to have anti-HBs concentrations of ≥10 mIU/mL after receipt of the primary vaccine series are considered immune, and the result should be documented. Immunocompetent persons have long-term protection and do not need further periodic testing to assess anti-HBs levels.”

CDC on Immunization of Health-Care Personnel

The alternative to screening healthcare workers after they complete their vaccination series is to do postexposure management. In this method, in the case of a needlestick or other blood or body fluid exposure, both the source patient and the health care worker are tested and postexposure prophylaxis is given as necessary.

Don’t pregnant women get tested for hepatitis B? They do, but not to see if they are immune from immunization. They routinely have a HBsAg test to see if they have a chronic hepatitis B infection, which can be passed on to their baby.

Other screening tests that can be done include anti-HBc (antibody to hepatitis B core antigen) and IgM anti-HBc (IgM subclass to hepatitis B core antigen). These two tests can help you figure out if a person has an acute infection or is immune from a past infection.

Non-Immune Hepatitis B Titer Levels

Why check the anti-HBs level?

Because of the devastating effects of chronic hepatitis B infections, it is good to have all of the information you can get to help prevent a possible infection if you are exposed to blood or body fluids while working.

Having a positive anti-HBs level, typically defined as a level of ≥10 IU/mL, means that you are immune and protected.

But what if your level is negative? What if your level is <10 IU/mL after you have already gotten three doses of hepatitis B vaccine?

Then you get another dose of hepatitis B vaccine and the level is checked again in one to two months. If it is still <10 IU/mL, then you get two more doses of hepatitis B vaccine and the level is checked again in one to two months.

If you are still negative after six or more doses of hepatitis B vaccine, then you are considered a non-responder. You would then require postexposure testing and possible prophylaxis if you are exposed to a patient’s blood or body fluids.

What If You Lost Your Hepatitis B Immunity?

There is a reason that they don’t recommend testing more than one to two months after your last dose of hepatitis B vaccine.

“Studies indicate that immunologic memory remains intact for at least 20 years and confers protection against clinical illness and chronic HBV infection, even though anti-HBs levels that once measured adequate might become low or decline below detectable levels. If one is challenged with HBV, people whose immune systems are competent will mount an anamnestic response and develop protective anti-HBs.”

Immunization Action Coalition on Hepatitis B Questions

It is known that anti-HBs levels can decrease over time.

Fortunately, this does not lead to waning immunity in typical circumstances. Because of an anamnestic response, the hepatitis B vaccine provides long lasting protection, even if your antibody levels appear to have dropped.

Avoiding Hepatitis B

Since health care workers should practice universal precautions whether or not they are immune to hepatitis B, being a non-responder isn’t going to change how you do things too much.

Plus, there are other diseases that are not yet vaccine preventable that you could get if you are stuck with a needle, so you are hopefully still very careful, no matter how immune you are to hepatitis B.

Still, it is very nice to have one less thing to worry about in this situation.

“Unvaccinated or incompletely vaccinated persons who experience a workplace exposure from persons known to be HBsAg-positive should receive 1 dose of hepatitis B immune globulin HBIG (i.e., passive vaccination) as soon as possible after exposure (preferably within 24 hours).”

CDC on Immunization of Health-Care Personnel

If you are a non-responder and and are exposed to hepatitis B, then one thing that is different is that you will likely require two doses of HBIG (hepatitis B immune globulin) for protection. Others can get one dose of HBIG and can repeat the hepatitis B vaccine. Those who are fully vaccinated and known to be immune likely won’t have to do anything to protect themselves from hepatitis B, although each incident should be investigated to make sure.

But it is not just healthcare workers who are at risk for accidental needlesticks. What if a healthcare worker sticks themselves and then you or your child? Or what if your child gets stuck with a discarded needle at the park?

What to Know About Hepatitis B Titers

Get vaccinated and follow the latest guidelines if you are exposed to hepatitis B, especially if you are a non-responder to the vaccine with low titer levels.

More on Hepatitis B Titers and Immunity

Did Your Rubella Titer Come Back Negative?

Two doses of the MMR vaccines give the great majority of people long lasting immunity to measles, mumps, and rubella. Well, measles and rubella anyway. Unfortunately, the mumps part of the vaccine has some issues with waning immunity.

Do you need to get your titers checked to make sure you are immune?

Usually not. Simply being fully vaccinated with the MMR vaccine is  good enough evidence that you are immune in most, but not all circumstances

Getting or being pregnant is one of those circumstances in which it is important to know for sure. It is really one of the only circumstances. Health care works are no longer routinely tested after they are vaccinated, as proof of vaccination is good evidence of immunity for the MMR vaccine.

The American College of Obstetricians and Gynecologists recommends that all pregnant women be screened for rubella.
The American College of Obstetricians and Gynecologists recommends that all pregnant women be screened for rubella.

That screening test is a rubella serum IgG levels or as it is more commonly known as, a titer level.

Non-Immune Rubella Titers

Why check it?

Because of the devastating effects of congenital rubella syndrome, all pregnant women are screened early in their pregnancy.

Babies with congenital rubella syndrome may have cataracts and many other birth defects.
Babies with congenital rubella syndrome may have cataracts and many other birth defects. Photo courtesy PHIL

Having a positive rubella titer, typically defined as a IgG level of ≥10 IU/mL, means that you are immune and protected.

But what if your rubella titer is negative? What if your level is <10 IU/mL?

We know that levels of vaccine-induced rubella antibodies can decrease over time, but unlike mumps and pertussis, this does not seem lead to waning immunity with rubella.

Still, the current recommendations from the Advisory Committee on Immunization Practices (ACIP) are that:

  1. Vaccinated women of childbearing age who have received one or two doses of rubella-containing vaccine and have a rubella serum IgG levels that is not clearly positive should be administered one additional dose of MMR vaccine, with a maximum of three doses.
  2. After this additional dose, they do not need to be retested for serologic evidence of rubella immunity.
  3. Since MMR is a live vaccine, the additional dose should not be given during pregnancy or within a month of when you plan to get pregnant. You can get it while you are breastfeeding though.

How much should you be concerned about a negative rubella titer?

Although congenital rubella syndrome is not uncommon in other countries that don’t routinely vaccinate for rubella, there has not been a case of congenital rubella syndrome in the United States since – 2017.

That’s right, we have actually had two cases of congenital rubella syndrome in the US this year! In past years, these cases have all been linked to pregnant women becoming infected outside the US though, as there are thought to be very few rubella infections locally.

And two cases is a far cry from when rubella caused 2,100 neonatal deaths and 20,000 infants to be born with congenital rubella syndrome during an epidemic in the mid-1960s, before the first rubella vaccine was available.

That’s because vaccines work.

Wait, then why do some of these folks have a negative titer when they are tested?

While the easy answer is to say that they aren’t immune, it is more complicated than that. For example, some of the negative results could be false negatives (a negative test result that really should be positive). Others could possibly have low antibody levels, but they are still immune. Still, since one dose of a rubella containing vaccine is only about 97% effective, some of them could be non-responders.

Will a second or third booster dose of vaccine help increase your antibody levels? Yes, but in this situation, they will likely just rise temporarily. The second or third dose of MMR isn’t technically a booster dose, but rather a dose for those who didn’t respond to the previous doses, particularly for the measles component.

Avoiding Rubella

With a negative rubella titer, especially if you have not been previously vaccinated with one or more rubella-containing vaccines, you should likely try to avoid anyone who might have rubella.

There aren’t a lot of guidelines on how to avoid rubella though.

If you want to avoid rubella, avoid folks who aren't vaccinated against rubella.
If you want to avoid rubella, avoid folks who aren’t vaccinated against rubella. Photo courtesy of PHIL

That probably surprises you, especially with all of the information out there on how to avoid the flu, measles, mumps, and other infectious diseases, but it shouldn’t.

Symptoms of a rubella infection can include swollen lymph glands, low grade fever, a mild case of pink eye, and a red rash that can be hard to see, unless the person is overheated, like after a bath. Most importantly, people with rubella can be contagious for another few weeks, even as all of the symptoms have gone away. Also, like most viral infections, they were contagious for a few days even before they developed their first symptoms. And, believe it or not, some people with rubella might have no symptoms at all and still be contagious.

So how do you avoid someone who doesn’t even know that they are sick and are still contagious?

You basically want to try and away from anyone who might become sick and contagious…

While that sounds impossible, avoiding kids and adults who are intentionally unvaccinated, especially those who are intentionally unvaccinated and have recently traveled out of the country, can be a good start.

And like someone with a medical exemptions to getting vaccinated, if you have been vaccinated and lost your immunity to rubella, feel free to hide in the herd. This is one of the reasons everyone gets vaccinated!

What to Know About Rubella Titers

Get vaccinated and follow the latest guidelines if you are pregnant and your rubella titer is negative.

More on Rubella Titers and Immunity

Precautions vs Contraindications When Vaccinating Your Kids

Believe it or not, there are some anti-vaccine folks who believe that all vaccines are dangerous and unnecessary. And they believe that pediatricians push vaccines on kids in all situations, using a one-size-fits-all kind of immunization schedule.

Of course, neither is true.

Vaccines are safe and necessary.

There are some true medical contraindications and precautions to getting vaccinated though. Still, it is important to remember that even more things are simply “conditions incorrectly perceived as contraindications to vaccination.”

Contraindications To Vaccinating Your Kids

There are actually some good reasons to delay or skip one or a few of your child’s vaccines, but only in some very specific situations.

These very specific situations are called contraindications and are what count as medical exemptions.

“A vaccine should not be administered when a contraindication is present; for example, MMR vaccine should not be administered to severely immunocompromised persons.”

CDC on Vaccine Contraindications and Precautions

Fortunately, there are not that many of these contraindications, they are usually specific to just one or a few vaccines, and they are usually, but not always, temporary.

That’s why it would be really unusual to get a true permanent medical exemption for all vaccines. Even if you had a severe allergy to a vaccine that contained yeast, latex, or gelatin, since vaccines contain different ingredients, you would very likely be able to safely get the others.

Remember, your doctor can’t, or at least shouldn’t, just make up contraindications and exemptions to help you avoid getting your kids vaccinated and help you keep them in school.

“I do not believe vaccines had anything to do with my child’s autism. I never noticed any change in his speech, behavior or development with vaccines. I believe the protection and benefits of vaccines far outweigh the risks!”

Michele Han, MD, FAAP

Autism, for example, has been shown to not be associated with vaccines, so it is not a contraindication to getting vaccinated. That’s why many parents vaccinate and protect their autistic kids!

Precautions To Vaccinating Your Kids

In addition to contraindications to getting vaccinated, there is an accompanying list of  precautions.

“A precaution is a condition in a recipient that might increase the risk for a serious adverse reaction, might cause diagnostic confusion, or might compromise the ability of the vaccine to produce immunity (e.g., administering measles vaccine to a person with passive immunity to measles from a blood transfusion administered up to 7 months prior). A person might experience a more severe reaction to the vaccine than would have otherwise been expected; however, the risk for this happening is less than the risk expected with a contraindication. In general, vaccinations should be deferred when a precaution is present. However, a vaccination might be indicated in the presence of a precaution if the benefit of protection from the vaccine outweighs the risk for an adverse reaction.”

CDC on Vaccine Contraindications and Precautions

Again, we are fortunate that most of the conditions that are listed as precautions are temporary.

The vaccine information sheet that you get with each vaccine will list contraindications and precautions on who should not get the vaccine.
The vaccine information sheet that you get with each vaccine will list contraindications and precautions on who should not get the vaccine.

In fact, the most common is having a “moderate or severe acute illness with or without fever.”

Don’t want to get your child vaccinated when he or she has a severe illness?

Don’t worry.

Your pediatrician usually doesn’t want to vaccinate your child in that situation either.

It is easy enough to wait a few days or a week to get vaccinated, when the illness has passed, keeping in mind that a “mild acute illness with or without fever” is neither a precaution nor a contraindication to getting vaccinated. So you can still get your child their recommended vaccines if they just have a cold, stomach bug, or ear infection, etc.

What to Know About Precautions and Contraindications to Vaccines

Although there are some true medical exemptions or contraindications and precautions to getting vaccinated, most are vaccine specific and many are temporary, so they shouldn’t keep you from getting your child at least mostly vaccinated and protected.

More on Precautions and Contraindications to Vaccines