Long-term monitoring of virus antibody titers in human intravenous immunoglobulin lots derived from donors in Japan.

BACKGROUND: Intravenous immunoglobulin (IVIG) contains immunoglobulin G against various viruses, except those that have been screened, such as human immunodeficiency and hepatitis C viruses. Antivirus titers reflect the serostatus of the blood donor population in the collection region and are of clinical interest.

STUDY DESIGN AND METHODS: During the past 10 years, measles, mumps, rubella, varicella-zoster, hepatitis A and B, Epstein-Barr, and human respiratory syncytial viruses; human parainfluenza viruses 1, 2, and 3; human herpes simplex viruses 1 and 2; human herpesvirus 6; cytomegalovirus (CMV); human adenoviruses (HAdVs) 1, 2, 3, 7, and 11; human parvovirus B19; and human echovirus 9 and 11 titers in IVIG lots have been measured by a commercial testing facility. A viral neutralizing assay for CMV has been used at our facility. Herein, we summarize the measurements and results of a regression analysis of the trends in virus antibody titers.

RESULTS: IVIG lots contained significant titers against all of the above viruses, except for HAdV 7. Three patterns-stable, increasing, and decreasing-were observed, without any drastic changes. Although these trends reflect the seroprevalence in Japan, the titers were not obviously affected by the cycle of epidemics. On the other hand, the prevalence data suggest that titers against hepatitis A virus and other viruses will decrease in the near future, although they are currently stable.

CONCLUSION: Monitoring the titer of IVIG lots and seroprevalence of donor populations is important for anticipating future changes in virus antibody titers of IVIG lots and can provide useful information of clinical interest.