Hepatitis A vaccine is the most frequently used traveler's vaccine, yet data on its ability to induce protective immunity in immunosuppressed travelers are scarce. The investigators assess the hepatitis A virus (HAV) antibody response in patients with rheumatoid arthritis (RA) treated with Tumor Necrosis Factor (TNF) - inhibitors and/or methotrexate (Mtx).

In a previous study, 2 doses were not considered effective and there is therefore need for a study with an additional dose

Methods: Parameters registered at baseline were: age, sex, duration of disease, medications, activity of disease (Visual Analogue Scale), Health Assessment Questionnaire Disability Index, Disease Activity Score, Acute phase reactant and total immunoglobulin G in plasma). Hepatitis A vaccine (Epaxal or Havrix) were given at 0 and 6 months. Hepatitis A virus (HAV) antibodies is measured before vaccination and at month 1, 6 (before dose 2), 7 and 12 with quantitative HAV IgG, using the HAVAb-IgG Architect System, and by the HAVAB 2.0 assay on the AxSYM machine from Abbott. The level of protective immunity to HAV is defined as HAV IgG > 10mIU/mL.

Inclusion Criteria:

• Diagnosis of rheumatoid arthritis
• TNF-alfa blocker and / or methotrexate in use as a medication against RA
• A desire to get protected against hepatitis A
• Men and women age 18-65 years
• Written informed consent
• Women of childbearing potential must use effective contraception -

Exclusion Criteria:

• Treatment with rituximab within 9 months before study start
• Known previous hepatitis A infection
• Previous vaccination against hepatitis A
• Allergy to eggs or formaldehyde
• Pregnancy or lactation
• Excessive use of alcohol
• Mental retardation
• Acute disease at the time of examination (fever > 38 degrees)
• Volunteer works as an employee of the researchers
• Previous vaccination against hepatitis A
• Egg-, hen-protein- or formaldehyde allergy
• Pregnancy or lactation
• Excessive use of alcohol
• Another vaccine given within a month
• Acute disease at the time of examination (fever > 38 degrees)
• Not suitable for other reason in the investigator's opinion (other serious disease, i.e. AIDS/HIV-positive, cancer with ongoing cytostatic treatment)