1. Department of Human Retrovirology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
2. Institute of Epidemiology and Infectious Diseases, Academy of Medical Sciences of Ukraine, 03038 Kiev, Ukraine
3. Department of Human Retrovirology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands; D.I. Ivanovsky Institute of Virology, Russian Academy of Medical Sciences, 123098 Moscow, Russia