The aims of this study were the following: a) to perform Epstein-Barr virus (EBV) strain type assignment in three groups of Hodgkin's disease(HD): adult ordinary (39 cases), paediatric (24 cases), and HIV-associated (30 cases) and to compare the prevalence of type 1 and type 2 in each of the groups with that existing in two reference populations made up of 50 adults and 39 children; b) to assess the frequency of latent membrane protein-1 (LMP-1) 30-base pair (bp) deletions in the HD groups and in the healthy controls; and c) to relate the presence of LMP-1 deletions with EBV type. Type 2 EBV was observed in 12.8% of ordinary HD, in 26.7% of HIV-associated HD, in 25% of paediatric HD, in 4% of adult controls, and in none of the healthy children. The existence of double infections by type 1 and 2 EBV was also observed in 5.1% of ordinary HD, in 6.7% of HIV-associated HD, and in 10% of adult controls. The 30-bp deletion was identified overall in 33.3% of ordinary HD, in 83.3% of HIV-positive HD, 79.2% of paediatric HD, 34.7% of adult controls, and 36.4% of healthy children. Statistical analysis showed a significant association of the deleted strains with HD occurring in HIV-positive patients (P= 0.00003) and childhood HD (P= 0.006). On the other hand, the prevalence of the 30-bp deletion in the adult ordinary HD group reflects the prevalence of the deletion in the general population. Co-infections by deleted and non-deleted EBV strains were detected in 12.8% of ordinary HD, in 33.3% of HIV-associated HD, in 50% of paediatric HD, in 26.5% of adult controls, and in 27.3% of healthy children. Concerning the relationship between the deletion and the EBV typing, 26% of type 1 specimens carried the 30-bp deletion in an isolated manner compared with 64.7% of type 2. The statistical analysis showed that the deletion was associated with type 2 strains when coinfections were excluded and only the cases in which the deletion appeared alone were considered (P=0.003).