1. M. P. Chumakov Institute of Poliomyelitis and Viral Encephalitides, Moscow, 142782, Russia.
2. A. N. Belozersky Institute of Physical-Chemical Biology, M. V. Lomonosov Moscow State University, Moscow, 119899, Russia.
3. Department of Molecular Genetics and Microbiology, School of Medicine, Stony Brook University, Stony Brook, NY 11794, USA.
4. Center for Biologics Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, MD 20903, USA.
5. NIAID, NIH, Bethesda, MD 20892, USA.