Roy W. Stevens

MOTHER-TO-INFANT TRANSMISSION OF HUMAN IMMUNODEFICIENCY VIRUS TYPE 1: ASSOCIATION WITH PREMATURITY OR LOW ANTI-gp120

In a prospective study of pregnant women infected with human immunodeficiency virus type 1 (HIV-1) in Brooklyn, New York, USA, 16 (29%) of 55 evaluable infants were infected with HIV-1. 9 infants had paediatric acquired immunodeficiency syndrome, 6 had less severe clinical manifestations of HIV-1 infection, and 1 was symptom-free but was seropositive for HIV-1 beyond 15 months of age. The 10 infants born at 37 weeks of gestation or earlier were at higher risk of HIV-1 infection than infants born at 38 weeks of gestation or later (60% vs 22%) but the median age at appearance of disease was approximately 5 months in both groups. The HIV-1 transmission rate was not associated with predelivery levels of maternal T cells, anti-p24, or neutralising antibodies but it was higher, among full-term infants, for those with mothers in the lowest third of the distribution of anti-gp120 levels (53%). On immunoblot, transmitting mothers lacked a gp120 band but not other bands. Protection was not associated with antibody to recombinant peptides from the hypervariable region of the major neutralising gp120 epitope, and the anti-gp120 endpoint dilution titre was similar in transmitting and non-transmitting mothers. Mothers of uninfected full-term infants appear to confer immunological protection against HIV-1 infection of their offspring by way of a high-affinity antibody to a gp120 epitope, whose specificity has importance for vaccine development and possibly perinatal immunotherapy.

The relationship of cocaine use to syphilis and human immunodeficiency virus infections among inner city parturient women

To study the relationship of cocaine use to syphilis and human immunodeficiency virus infections a blinded urine and serum survey was performed among parturient women at an inner city hospital. Discarded urine samples of 1206 parturient women were saved and given code numbers that were also assigned to data sheets containing nonidentifying information, including prenatal care status and syphilis serologic results. In the latter part of the study blood remaining after syphilis serologic tests were performed (n = 480) were tested for human immunodeficiency virus antibodies. Overall 12.9% of urine samples had cocaine derivatives, 1.4% opiates, 1.5% marijuana, 0.0% benzodiazepine, and 0.3% methadone. The prevalence of positive rapid plasma reagin tests was 18.7% among patients with positive urine toxicologic tests for cocaine and 2.41% for patients with negative urine tests (odds ratio = 9.3, 95% confidence interval 5.2 to 16.5, p less than 0.001). Fluorescent treponemal antibodies were also significantly more frequent among patients with positive urine samples. Four of 53 (7.6%) patients with positive urine toxicologic screens were human immunodeficiency virus antibody positive compared with six of 427 (1.4%) women with negative screens (odds ratio = 5.7, 95% confidence interval = 1.4 to 21.5, p = 0.019). Cocaine patients with positive cocaine screens and with syphilis or human immunodeficiency virus had prenatal care in 6 of 21 (28.6%) and 0 of 4 (0%) cases, respectively, while patients with negative cocaine screens and syphilis or human immunodeficiency virus had prenatal care in 13 of 18 (72.2%) and 5 of 6 (83.3%) cases, respectively (p = 0.010 and p = 0.048). Cocaine use appears to be associated with both the acquisition of human immunodeficiency virus and syphilis and the failure of infected individuals to utilize prenatal services.

Toxoplasma gondii: purification of trophozoites propagated in cell culture.

Abstract A new procedure is described for the purification of trophozoites from the virulent RH strain of Toxoplasma gondii propagated in baby hamster kidney (BHK-21) cell cultures. The culture medium containing host cell debris and trophozoites was filtered through glass-wool filtering fiber, which removed most host cell material. The filtrate containing trophozoites was centrifuged, and the trophozoite pellet was resuspended and washed in phosphate-buffered saline. An average of about 75% of the original number of trophozoites was recovered. No loss of trophozoite viability was observed as determined by the rate of host cell culture monolayer destruction. The amount of host cell material contamination in the final trophozoite fraction was negligible as determined by measuring radioactivity in the trophozoite fraction after cofiltration with noninfected host cell material which had been prelabeled with radioactive precursors.

Fluorescent Treponemal Antibody Test Using the Reiter Treponeme.

Summary A fluorescence test for treponemal antibody using the in vitro cultured Reiter treponeme compares favorably in sensitivity and specificity for syphilis with one requiring the virulent Nichols strain of T. pallidum which must be cultivated in vivo.

Possible Typhus‐Group Infection in New York State: Presentation of Four Suspect Cases

Epidemiologic investigations were recently conducted on four cases which were reported in New York State in 1986 and 1987, three of which were within one family. These included hospital chart reviews, case or family interviews, animal trappings, and ectoparasite surveys. Serologic tests and immunoblots were performed on blood samples obtained from these patients. All four patients had acute febrile illnesses; two required hospitalization and one died. Microimmunofluorescence test results using Rickettsia typhi and R. prowazekii antigens showed a greater than or equal to 4-fold increase in titer with paired sera from three patients. The remaining patient had a single serum titer of 4096 with both antigens. In addition, sera from all patients reacted with R. typhi in the immunoblot test and, from the three patients for whom sera were available, also with R. prowazekii. Results suggest that the four patients were exposed to the typhus-group rickettsiae or to an organism which shares a common epitope(s).

Inhibition of Trichinella spiralis complement fixation by immune macroglobulin.

Summary Trichinella spiralis immune human serum macroglobulin inhibits complement fixation with Trichinella carbohydrate and whole serum. The macroglobulin preparations possess specific agglutination activity and the inhibitor is characterized as immunoglobulin M (IgM) which does not incorporate complement in its union with antigen.