Vaccination has become a controversial subject lately, especially in the United States. A fraudulent paper, published in 1998, claimed there was a link between children getting an MMR (measles, mumps, and rubella) vaccine and developing autism. That paper has long since been debunked and retracted, but the fears it highlighted in parents have persisted. This is relevant to the recent outbreak of 50 or so cases of measles, which was linked to unvaccinated individuals at Disneyland in California. In fact, measles seems to be returning; there were more cases of measles in 2014 than in the previous four years combined, and this is likely due to non-compliance with recommended vaccinations. This article isn’t about vaccinations in general; rather, it discusses celiac disease and vaccinations, specifically.
Celiac disease is an autoimmune disorder that can occur in genetically predisposed people where the ingestion of gluten leads to damage in the small intestine. People with celiac disease are also at more risk for other autoimmune diseases. Therefore, it is not unreasonable to wonder if the immune system of celiac patients is different in other ways, such as how they respond to vaccinations. However, other than the autoimmune issues, patients with celiac disease have healthy and functioning immune systems, and for the most part, vaccinations work just as effectively as they do in the general population. There is one notable exception that has been uncovered: hepatitis B.
Hepatitis B is a disease that affects the liver. Caused by the hepatitis B virus (HBV), it can be transmitted through blood and other bodily fluids. Hepatitis B can present either chronically or acutely, but both kinds can be fatal. The disease in present in less than 1% of North Americans, but is still common in sub-Saharan Africa and East Asia.
The hepatitis B vaccine has been around since the 1980s and it is one of the safest vaccines available. The World Health Organization suggests vaccinating infants in their first day of life, as well as later on for the full protective effect. Like all vaccines, there is some percentage of people who simply do not respond, and therefore do not develop immunity to the disease. There are many factors that are associated with non-responsiveness, such as smoking habits, age, and obesity. This is one reason, among others, that it is important for as many people as possible to get vaccinated, so that these “non-responders” are protected from the disease through “herd immunity”. When enough people are successfully immunized against a disease, it helps protect people who are still vulnerable by reducing their contact to the disease. Even if someone had no response to a vaccine against a harmful disease, as long as everyone around them was vaccinated, the person won’t ever have the chance to contract the disease; this is herd immunity. In the general population, about 4-10% of people are non-responders.
For celiac patients, the hepatitis B vaccine is just as safe, but it is far less effective. In a study published back in 2003, Dr. Joseph Murray of the CDF Medical Advisory Board, and other researchers, searched through a medical database and found that out of 19 people with celiac disease who also were vaccinated for hepatitis B, 13 did not show an adequate response. Many studies have confirmed that celiac patients have a very high rate of non-response to the hepatitis B vaccine.
The exact reason for this phenomenon is most likely genetic, at least in part. Interestingly, a 2007 study out of Hungary found that celiac patients who were already being treated with a gluten-free diet fared much better than those still eating gluten. The paper, titled “Gluten Intake Interferes With the Humoral Immune Response to Recombinant Hepatitis B Vaccine in Patients With Celiac Disease,” monitored blood antibody levels in children to keep track of both celiac disease activity (transglutaminase and endomysium antibodies) and hepatitis B immunity (anti-HBs).
The researchers in that study found that not only did the children on a gluten-free diet respond as well as the control group to the hepatitis B vaccine, but children who initially showed no response to the vaccine were able to later develop immunity by going on a gluten-free diet and getting re-vaccinated. The authors also suggest that patients who do not respond to the hepatitis B vaccine be tested for celiac disease.
These results were mirrored by another study done in Turkey around the same time in 2010. The group of researchers tested known celiac patients who had been vaccinated for hepatitis B, and found that the rate of non-response was significantly higher in the celiac patients when compared to controls (32.5% versus 14.8% respectively). But in celiac patients who were vaccinated after they were diagnosed and already on a gluten-free diet, the difference in response rate was insignificant. From these studies, it seems that only patients with active and untreated celiac disease are at risk for not responding to the hepatitis B vaccine.