FIG. 1.

Chronology of PBMC and plasma samplings for the two nurses and the patient. Rectangles represent periods of hospitalization; vertical plain and dashed arrows indicate sampling of lymphocytes and plasma, respectively. Nurse 1 and nurse 2 had been in contact, between May 28 and June 8, 1996, each during two nights (indicated by asterisks), with the patient, who had a negative HIV-1 serology and no detectable viral RNA at the time of her hospitalization. Nurse 1 had been aware of his HIV-1 seropositivity for 5 years, and HIV-1 sequences were characterized from lymphocytes (N1) obtained on February 19, 1997, i.e., after the virological investigation was requested. Nurse 2's HIV serological status was unknown until she was diagnosed with HIV-1 and HCV infection during a hospitalization that started on June 20, 1996. The first nurse 2 HIV sequence (N2) used for molecular epidemiology analyses was from lymphocytes obtained on May 7, 1997, 1 month after introduction of antiretroviral treatment. Retrospectively, we also characterized viral sequences from cryopreserved plasma samples (JV44 and JV27) obtained during nurse 2's hospitalization. The second hospitalization (July to August 1996) of the patient was for HIV-1 primary infection. Plasma (JV32 and JV48) and lymphocyte (P) samples were obtained from the patient for viral sequence amplification. HIV-1 viral load, when available, is indicated (logarithm of the number of copies per milliliter) above corresponding sampling pointers.