George J Pazin
George J Pazin
1From the Departments of Infectious Diseases and Microbiology and of Biostatistics, Graduate School of Public Health
2
Departments of Medicine and of Obstetrics and Gynecology, School of Medicine, University of Pittsburgh, Pennsylvania
3
Department of Virology, Central Public Health Laboratory, Helsinki, Finland
1,2,3,
James H Harger
James H Harger
1From the Departments of Infectious Diseases and Microbiology and of Biostatistics, Graduate School of Public Health
2
Departments of Medicine and of Obstetrics and Gynecology, School of Medicine, University of Pittsburgh, Pennsylvania
3
Department of Virology, Central Public Health Laboratory, Helsinki, Finland
1,2,3,
John A Armstrong
John A Armstrong
1From the Departments of Infectious Diseases and Microbiology and of Biostatistics, Graduate School of Public Health
2
Departments of Medicine and of Obstetrics and Gynecology, School of Medicine, University of Pittsburgh, Pennsylvania
3
Department of Virology, Central Public Health Laboratory, Helsinki, Finland
1,2,3,
Mary K Breinig
Mary K Breinig
1From the Departments of Infectious Diseases and Microbiology and of Biostatistics, Graduate School of Public Health
2
Departments of Medicine and of Obstetrics and Gynecology, School of Medicine, University of Pittsburgh, Pennsylvania
3
Department of Virology, Central Public Health Laboratory, Helsinki, Finland
1,2,3,
Richard J Caplan
Richard J Caplan
1From the Departments of Infectious Diseases and Microbiology and of Biostatistics, Graduate School of Public Health
2
Departments of Medicine and of Obstetrics and Gynecology, School of Medicine, University of Pittsburgh, Pennsylvania
3
Department of Virology, Central Public Health Laboratory, Helsinki, Finland
1,2,3,
Karl Cantell
Karl Cantell
1From the Departments of Infectious Diseases and Microbiology and of Biostatistics, Graduate School of Public Health
2
Departments of Medicine and of Obstetrics and Gynecology, School of Medicine, University of Pittsburgh, Pennsylvania
3
Department of Virology, Central Public Health Laboratory, Helsinki, Finland
1,2,3,
Monto Ho
Monto Ho
1From the Departments of Infectious Diseases and Microbiology and of Biostatistics, Graduate School of Public Health
2
Departments of Medicine and of Obstetrics and Gynecology, School of Medicine, University of Pittsburgh, Pennsylvania
3
Department of Virology, Central Public Health Laboratory, Helsinki, Finland
1,2,3,✉
1From the Departments of Infectious Diseases and Microbiology and of Biostatistics, Graduate School of Public Health
2
Departments of Medicine and of Obstetrics and Gynecology, School of Medicine, University of Pittsburgh, Pennsylvania
3
Department of Virology, Central Public Health Laboratory, Helsinki, Finland
✉Please address requests for reprints to Dr. Monto Ho, Crabtree Hall A-427, University of Pittsburgh, Pittsburgh, Pennsylvania 15261.
Received 1987 Feb 2; Revised 1987 Jul 10; Issue date 1987 Dec.
© 1987 The University of Chicago
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