1. Grant Medical College and Sir JJ Hospital, Byculla, Mumbai, India.
2. Laboratoire de Virologie EA 2968, Université de Bordeaux 2, 33076 Bordeaux, France.
3. Haffkine Institute, Parel, Mumbai, India.
4. Laboratoire de Virologie EA 2968, Universit. de Bordeaux 2, 33076 Bordeaux, France.