Paul D. Parkman

Isolation of Attenuated Rubella-Vaccine Virus from Human Products of Conception and Uterine Cervix

Abstract To evaluate the fetal hazard of accidental administration of live rubella vaccine during pregnancy, the vaccine was given to 35 women certified for legal abortion. Twenty-four of these wer...

Inadvertent Rubella Virus Vaccination during Pregnancy

Abstract Studies concerning nine pregnant women inadvertently inoculated with live rubella virus vaccine confirmed that the attenuated virus can produce chronic placental infection. None of the women had been tested for rubella susceptibility before vaccination; however, serologic testing of later serum specimens indicated seroconversion of one. This subject and one other reported symptoms consistent with vaccine-virus infection. In both women the attenuated virus was isolated from conceptuses collected 69 and 28 days respectively after immunization. Attempts at virus isolation were negative on specimens from the remaining six women. Histologic changes in placenta or decidua consistent with rubella infection were detected in the two virus-positive cases and in one negative case. These data underscore the need for caution in vaccinating postpubertal women.

Immune Status of Children One to Four Years of Age as Determined by History and Antibody Measurement

Abstract Measurement of serum antibody levels in children one to four years old, living in three city and one suburban census tract, revealed that 63 per cent of the total study population were susceptible to rubella and approximately 33 per cent had inadequate titers of measles antibody. Antitoxin levels to diphtheria and tetanus were low in 24 and 7 per cent respectively of the entire study group. A large proportion (57 per cent) of these children had serum antibody levels of less than 10 to one or more types of poliovirus. Many had low antibody levels after the recommended number of immunizations; others had not received adequate poliomyelitis vaccine. Although those with low levels may not contract paralytic disease, if reinfected with wild poliovirus, they may spread the infectious agent to susceptible persons in the environment. Increased effort should be made to immunize all preschool children. Advisory committees should consider the need for periodic reimmunization. (N Engl J Med 289:231–235, 1973)

Enhancement of Polio-RNA Infectivity by Dimethylsulfoxide

Summary Dimethylsulfoxide (DMSO) has been shown to enhance infection by polio-RNA. This enhancement was present for all concentrations of DMSO from 5% to 80%. The enhancement was optimal at 40% DMSO with a 20-minute absorption period at room temperature. A significant percentage of the nucleic acid infectivity was absorbed in the first two minutes. Dimethylsulfoxide enhanced RNA infection to a greater degree than M MgSO4, protamine, his tone, and DEAE-dex-tran when tested under the same conditions. There was no enhancement of intact viral infectivity by either DMSO or DEAE-dextran. Addendum: Recently Koch et at(20) have shown an enhancement of polio-RNA infectivity using Poly-L-Ornithine which appears to be slightly greater than DEAE-dextran. The technical assistance of Mr. Bruce Mann is greatly appreciated.

Density Gradient Ultracentrifugation of Rubella Virus

Summary The buoyant density of rubella virus HA was determined to be 1.23 in Cs2SO4. A density of 1.33 was obtained in CsCl. Rubella virus HA, either Tween-80. ether-treated or untreated, and infectivity could not be separated on sucrose by rate zonal or density gradient techniques. These activities also could not be separated on CsCl and Cs2SO4 density gradients. The banding density of rubella virus HA preparations was unaffected by the type of cell culture used for antigen production; neither the passage level nor the strain of virus altered the point at which rubella virus HA banded in CsCl.