Variability of Virus Antibodies in Intravenous Immune Globulins: West Nile Virus, Echo Viruses 9, 11, 13, 30

Abstract

RATIONALE: Individual lots of IVIG are produced from thousands of plasma donations, and thus reflect the serostatus of a large donor population. The titers against emerging viruses (e.g. West Nile Virus) or viruses with fluctuating epidemiology (e.g. Echo viruses) may still vary in IVIG, depending on where/from which donor community plasma was collected. METHODS: Neutralizing antibodies were determined for • West Nile Virus • Echo virus serotypes 9, 11, 13, 30 in IVIG lots produced from plasma collected in different • geographies, i.e. Europe and the US • donor communities, i.e. plasmapheresis vs. recovered from blood donations RESULTS: Testing IVIG lots produced from plasma collected prior to and after the 1999 introduction of WNV into the US, the seroconversion of parts of the US population (approx. 1%) is demonstrated. The WNV neutralization titers of currently produced IVIG lots still differ significantly, ranging from undetectable to comparable with individuals with past WNV infection. Echovirus neutralization titers in IVIG lots vary widely, for different serotypes as well as different geographies and plasma donor communities. The information may be relevant in the rare situations when Echovirus infections occur even in IVIG substituted individuals. CONCLUSIONS: IVIG lots reflect the virus epidemiology of specific donor communities, and some of the differences observed may potentially be of relevance in certain clinical circumstances.