1 Carol Davila University of Medicine and Pharmacy, Bucharest, Romania; Dr Victor Babes Clinical Hospital of Infectious and Tropical Diseases, Bucharest, Romania. Electronic address: cornel160@yahoo.com.
2 Carol Davila University of Medicine and Pharmacy, Bucharest, Romania; Dr Victor Babes Clinical Hospital of Infectious and Tropical Diseases, Bucharest, Romania.
3 Carol Davila University of Medicine and Pharmacy, Bucharest, Romania; Stefan S. Nicolau Institute of Virology, Bucharest, Romania.