Tag: needle stick

How Often Should You Do Vaccine Titer Testing?

We sometimes hear about folks doing vaccine titer testing.

A vaccine titer is a blood test that can determine whether or not you are immune to a disease after you get a vaccine.

While that sounds good, after all, why not check and be sure, it has downsides. Chief among them is that the results aren’t always accurate.

That’s right. You can sometimes have a negative titer test, but still be immune because of memory B cells and the anamnestic response.

How Often Should You Do Vaccine Titer Testing?

So how often should you do vaccine titer testing?

It depends, but most folks might never have it done!

Why not?

Vaccines work very well, so you would typically not need to routinely check and confirm that you are immune after being vaccinated. And, this is also important, the vaccine titer tests don’t always work that well, titer testing isn’t available for all vaccines (you can’t do titer testing for Hib and pertussis), and the testing can be expensive.

So we usually just do the testing (a quantitative titer) for folks that are in high risk situations, including:

  • pregnancy – rubella titer only (HBsAg is also done, but that’s not a vaccine titer test, but rather to see if you are chronically infected with hepatitis B)
  • healthcare workers – anti-HBs (antibody to the hepatitis B surface antigen to confirm immunity after being vaccinated)
  • students in nursing school and medical school, etc. – anti-HBs
  • children and adults exposed in an outbreakmeasles, chicken pox, mumps, etc., but only if we are unsure if they were previously vaccinated and protected
  • after a needlestick injury, etc. – to confirm immunity to hepatitis B
  • babies born to a mother with hepatitis B – to confirm that their hepatitis B vaccine worked

Vaccine titer testing might also be done for:

  • internationally adopted children – to confirm that they are immune if we unsure about all of the vaccines the child got in other countries
  • children and adults with lost vaccine records – to confirm that they are immune, since we are unsure about all of the vaccines they got
  • evaluation of children and adults with immune system problems – to help identify what immune system problems they might have – typically involves checking pneumococcal titers, giving Prevnar, and then checking pneumococcal titers again
  • people at continuous or frequent risk for rabies – rabies titer testing every 6 months to 2 years
  • patients with inflammatory bowel disease, before starting immunosuppressive therapy – hepatitis A and hepatitis B titers, as they might be at increased risk for hepatitis

While checking titers is easy, it is sometimes harder to know what to do with the results you get.

Of all of these different titers, only one tells you that you are immune due to vaccination.
Of all of these different titers, only one tells you that you are immune due to vaccination.

It is especially important to know that:

  • most people don’t need to have their titers checked routinely if they are not in one of the high-risk groups noted above
  • it isn’t practical to get titers tested as a method of potentially skipping one or more doses of your child’s vaccines, after all, if the titer is negative, then you are still going to have to get vaccinated
  • a healthcare provider with a negative measles titer after two doses of the MMR vaccine does not need another dose of vaccine
  • a healthcare provider who has anti-HBs <10 mIU/mL (negative titer) after three doses of the hepatitis B vaccine should get another dose of vaccine and repeat testing in 1 to 2 months – if still <10 mIU/mL, they should then get two more doses of hepatitis B vaccine (for a total of 6 doses) and repeat testing. If still negative, these documented nonresponders will need HBIG as post-exposure prophylaxis for any future hepatitis B exposures, but no further doses of hepatitis B vaccine.
  • vaccinated women of childbearing age who have received one or two doses of rubella-containing vaccine and have rubella serum IgG levels that is not clearly positive should be administered one additional dose of MMR vaccine, with a maximum of three doses, and should not be tested again
  • postvaccination titer testing is not recommended after the chicken pox vaccine
  • in addition to not being able to test titers for pertussis and Hib immunity, it is becoming difficult to test poliovirus type 2 titers, as the test uses a live virus that isn’t routinely available anymore (type 2 polio has been eradicated)

Still think you need vaccine titer testing?

More on Vaccine Titer Testing

What to Do If Your Child Is Exposed to Hepatitis B

Hepatitis B is a vaccine-preventable disease.

“In the United States, based on national health surveys, there are approximately 850,000 persons living with chronic HBV infection. However, estimates based on other methods and data yield estimates as high as 1.29 to 2.2 million persons with chronic HBV infection.”

Manual for the Surveillance of Vaccine-Preventable Diseases

That doesn’t mean that your child can’t be exposed at some point though.

What to Do If Your Child Is Exposed to Hepatitis B

Hepatitis B is mainly spread through blood and body fluids, which is why some folks consider the hepatitis B vaccine an STD vaccine.

“If you are concerned that you might have been exposed to the Hepatitis B virus, call your health professional or your health department. If a person who has been exposed to Hepatitis B virus gets the Hepatitis B vaccine and/or a shot called “HBIG” (Hepatitis B immune globulin) within 24 hours, Hepatitis B infection may be prevented.”

CDC on Hepatitis B FAQs for the Public

It is also possible to get hepatitis B from exposure from an infected family member or caretaker, or much more rarely, in a daycare or school setting.

So what do you do if your child is exposed to hepatitis B?

It depends.

Kids should complete the three dose hepatitis B vaccine series by the time they are 18 months old.
Kids should complete the three dose hepatitis B vaccine series by the time they are 18 months old.

Not surprisingly, one of the biggest factors that will determine what needs to be done is whether or not your child has completed a three dose hepatitis B vaccine series.

First things first though.

Before going any further, you will want to confirm that the person that exposed your child actually has hepatitis B (has a positive HBsAg level).

Next, confirm that it was a real exposure, which the AAP Red Book defines as “a discrete, identifiable percutaneous (eg, needlestick, laceration, bite or nonintact skin), mucosal (eg, ocular or mucous membrane), or sexual exposure to blood or body fluids.”

Keep in mind that the hepatitis B virus is not spread by casual contact, like hugging, kissing, holding hands, or even sharing silverware. It can be spread by having unprotected sex or sharing needles with someone who is infected, but also by coming into contact with open sores, getting bitten, sharing personal-care items, sharing chewing gum, or an unintentional needle stick at a doctor or dentist office or from a needle picked up in the community (park, playground, or street, etc.).

And of course, a newborn baby can be exposed if their mother has hepatitis B.

Biting and Hepatitis B

Young kids, especially toddlers, often go through a biting phase.

Do you have to worry about hepatitis B every time your child gets bit or bites someone?

Fortunately, no.

If any of the kids involved include one that is known to have hepatitis B, then talk to your pediatrician and follow the exposure guidelines.

Keep in mind that one of the reasons we don’t have to worry about these very low risk situations is because most kids are now vaccinated. There were more reports of kids and adults getting hepatitis B in unusual ways in the pre-vaccine era.

What to Do If Your Unvaccinated Child Is Exposed to Hepatitis B

If your unvaccinated child, or incompletely vaccinated child, is exposed to hepatitis B, you should talk to your pediatrician or local health department about starting post-exposure prophylaxis as soon as possible and preferably within 24 hours of the exposure (and not longer than 7), including:

  • a dose of HBIG
  • the first dose of hepatitis B vaccine, with plans to complete the three dose series as quickly as possible over the next 6 months

If you aren’t sure if the person had hepatitis B, then your unvaccinated child should likely just complete the three dose hepatitis B series without getting HBIG.

What to Do If Your Vaccinated Child Is Exposed to Hepatitis B

Unfortunately, if your vaccinated child is exposed to hepatitis B, you can’t simply assume that your child is protected and ignore the exposure. That is, unless your child has already had testing to confirm that he was a responder to the hepatitis B vaccine series – a HBsAb level of 10 or greater.

Since this titer test isn’t routinely done, your child will likely need a booster dose of the hepatitis B vaccine. A dose of HBIG isn’t needed.

If you aren’t sure if the person that exposed your child had hepatitis B, then your fully vaccinated child doesn’t need any additional treatment.

Getting Exposed to Hepatitis B in a Healthcare Setting

It should be noted that the guidelines are a little different and more aggressive if you are exposed in a healthcare setting vs your child having a nonoccupational exposure to hepatitis B.

Why?

There is probably more risk of getting infected from an occupational exposure where patients might be sick with hepatitis B. That’s why post-exposure testing on the exposed person is routinely done.

And since they are at risk for continued exposures, post-treatment testing, if required, to confirm a good response to the hepatitis B vaccine is also usually done.

What to Know About Getting Exposed to Hepatitis B

Hepatitis B exposures can come from more than just having sex or getting stuck with a needle. Learn what to do if your child is exposed to hepatitis B, especially if they aren’t already fully vaccinated and protected.

More on Getting Exposed to Hepatitis B

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