Researchers from Israel have found a possible link between some cases of chronic fatigue syndrome (CFS) and fibromyalgia (FM) and the hepatitis B vaccine. The study was published in Immunologic Research.

The purpose of this research was to gather information about people who had been diagnosed with FM or CFS after receiving the hepatitis B vaccination, spurred by patient reports of a possible association. The researchers used recently developed criteria for identifying autoimmune (auto-inflammatory) syndromes induced by adjuvants — known by the acronym ASIA — to try to find common clues that link FM, CFS and HBV vaccination.

Led by Nancy Agmon-Levin and Yaron Zafrir of The Zabludowicz Center for Autoimmune Diseases, Tel-Hashomer, Israel, the researchers analyzed medical records from 19 patients, with an average age of 29 years, who acquired CFS and/or FM after receiving a hepatitis B vaccine. All of the study participants received the vaccine between 1990-2008 at different medical centers in the United States. The investigators collected data on medical history, number of vaccine doses, immediate and long term post-immunization side effects and clinical problems. They also studied any available blood tests, imaging results, treatments and outcomes of those treatments.

The scientists found that 68% of the study participants were females and 21% had a background of autoimmune disease–either in their own medical history or in that of their family. The average time from the last dose of hepatitis B vaccine to the start of CFS or FM symptoms was 39 days, and lasted from several days up to a year. Eight of the patients continued with vaccination even though they had side effects from the treatment. Common side-effects were neurological (84%), musculoskeletal (79%), psychiatric (63%), fatigue (63%), gastrointestinal problems (58 %) and problems with mucus membranes (37%). In 71% the researchers found autoantibodies. All of the study participants fulfilled the ASIA criteria, which means that they had symptoms that indicated that they were experiencing side effects because of the vaccination, which is one of the ASIA criteria. A full explanation of ASIA criteria can be found at the following link.

The authors concluded that “This study suggests that in some cases CFS and FM can be temporally related to immunization, as part of ASIA syndrome. The appearance of adverse event during immunization, the presence of autoimmune susceptibility and higher titers of autoantibodies all can be suggested as risk factors.”

It should be noted that the study included a small number of subjects, so larger studies are warranted. However, this report may indicate a possible link between hepatitis B vaccination and the development of CFS or FM symptoms.