A look-back investigation of patients of an HIV-infected physician. Public health implications

BACKGROUND

Transmission of the human immunodeficiency virus (HIV) to five patients receiving care from an HIV-infected dentist in Florida has recently been reported. Current data indicate that the risk of HIV transmission from health care workers to patients is low. Despite this low risk, programs to notify patients of past exposure to an HIV-infected health care worker are being conducted with increasing frequency.

METHODS

We recently conducted an investigation of all the patients cared for by an HIV-infected family physician during a period when he had severe dermatitis caused by Mycobacterium marinum on his hands and forearms. After reviewing the patients' records, we notified 336 patients who had undergone one or more procedures (digital examination of a body cavity or vaginal delivery) placing them at potentially increased risk of HIV infection. The patients were offered tests for HIV infection and counseling.

RESULTS

Of the 336 patients, 325 (97 percent) had negative tests for HIV antibody, 3 (1 percent) refused testing, 1 (less than 1 percent) died of a cause unrelated to HIV infection before notification, and the HIV-antibody status of 7 (2 percent) remained unknown. The direct and indirect public health costs of this investigation were approximately $130,000.

CONCLUSIONS

The results of this investigation raise important questions about the risk of HIV transmission from health care workers to patients and the usefulness of HIV look-back programs, particularly in the light of recently published recommendations from the Centers for Disease Control. We propose that before a look-back investigation is undertaken, there should be a clearly identifiable risk of transmission of the infection, substantially higher than the risk requiring limitation of an HIV-infected health care worker's practice prospectively.

Nonmosaic verruca plantaris: treatment with a salicylic acid polymeric matrix delivery system

Ten patients who presented with nonmosaic plantar warts were treated with a new polymeric matrix patch delivery system containing salicylic acid USP, 21 percent. Clinicians then assessed the potential value of this patch system in terms of efficacy, length of treatment time required, patient compliance, and tolerance.

Unavailability of polynuclear aromatic hydrocarbons from coal particles to the eastern oyster

The accumulation by oysters of polycyclic aromatic hydrocarbons (PAH) from coal dust entering the estuarine environment has been postulated in the vicinity of coal transfer operations. Oysters Crassostrea virginica were exposed to coal dust plus 15 day leachate at concentrations of 10 mg litre(-1) and 1 mg litre(-1) coal dust for 28 days in a flow-through test system. Potential effects of the exposures were measured by comparing the uptake of PAH and the growth of the exposed animals versus control groups. Oysters sampled at 7, 14 and 28 days did not exhibit an increase in PAH body burden over control animals provided the guts were first purged of particulates. Even at the high test concentrations (10 mg litre(-1)), no effect of the exposure on shell growth was observed.

Methylphenidate and children with attention deficit disorder. Dose effects on classroom academic and social behavior

The short-term, dose-response effects of methylphenidate hydrochloride were evaluated on academic and social classroom measures in 29 children with attention deficit disorder. In a double-blind, cross-over design with order randomized, children received a placebo for two weeks and three doses of methylphenidate hydrochloride (0.15 mg/kg, 0.3 mg/kg, and 0.6 mg/kg) for one week each. Dependent measures included the output and accuracy of performance in grade-appropriate reading comprehension workbooks and arithmetic problems, spelling word acquisition, and observations of disruptive and on-task behavior. Beneficial drug effects and linear dose-response curves on all dependent measures were found. The results suggest that beneficial methylphenidate effects on classroom behavior may be accompanied by enhanced academic achievement in some hyperactive children.

Epidermodysplasia verruciformis in a setting of common variable immunodeficiency

A 14-year-old native American female with common variable immunodeficiency was admitted for bone marrow transplantation. Preoperative evaluation showed a generalized lichenoid papular eruption present for several years. Light microscopy revealed expansion of the epidermis by atypical keratinocytes; electron microscopy showed intranuclear papillomavirus inclusions within the granular keratinocytes; DNA hybridization revealed a type 5-related human papilloma virus homology. Four days after bone marrow transplantation the lichenoid papules blackened and began to disappear. Within 30 days after bone marrow transplantation the distribution and appearance of the papules was similar to that of the pretransplantation evaluation. One year after transplantation the patient showed evidence of a successful T lymphocyte graft. No transformation to squamous cell carcinoma had occurred. Epidermodysplasia verruciformis has been associated with deficient cell-mediated immunity, the varying severity of which does not predict the tendency to neoplasm formation (2, 5). Several distinct human papillomavirus genomes have been recovered with DNA hybridization techniques in these patients. It is hoped that the bone marrow transplantation might be associated with diminished transformation to squamous cell carcinoma.

Immunology of human papillomavirus: warts

Great progress has been made over the last five years in our understanding of papillomavirus (PV) biology. New technology has enabled investigators to understand the relationship between the PV and its host. The PV cannot be cultured in vitro, and this has led to limitations for those wishing to study the biology of this virus. However, utilizing recombinant DNA technology, investigators now have abundant quantities of human papillomavirus (HPV) DNA for study. Such HPV genomes may be labeled with a radioisotope such as P32 and used as a "probe" in hybridization studies to see if a given tissue contains HPV DNA. No longer are we limited to electron microscopy and immune studies in our efforts to identify HPV within benign or malignant tissues. Ultimately, we hope to understand the relationship between the virus and its host. This paper will concentrate on one aspect of this relationship--the immunology of HPV.

ECOLOGICAL EFFECTS OF EXPERIMENTAL OIL SPILLS ON EASTERN COASTAL PLAIN ESTUARINE ECOSYSTEMS

Five segments of a mesohaline marsh located off the York River in Virginia were physically isolated from the surrounding area, except for allowing subtidal flow, and dosed with fresh and artificially weathered South Louisiana crude oil. The experimental design and field site utilized in this study are described. The mini-ecosystems each contained about 695 m2 of marsh, 100 m2 of open water and 15 m2 of intertidal mud flat. In September 1975, three barrels (5701) of each of the experimental oils were spilled into replicate systems.

Overall, the artificially weathered oil was shown to have as great an ecological impact on the communities as the fresh crude. Phytoplankton and fish populations all showed greater declines following the spills in the weathered oil systems. Phytoplankton production declined immediately after both oil spills but had recovered to control values within seven days. Species composition was not affected by the oils, while periphyton biomass, as measured by adenosine triphosphate (ATP), increased after both treatments. Marsh grass production was reduced in both spill units. Benthic animals, showing population declines after both oil spills, included nereid polychaetes, insect larvae and amphipods. Oligochaete populations decreased shortly after the fresh crude spill, returned to normal within 30 days, and then declined again relative to the control in both treatments 11 weeks after the spill. Mortalities offish, Fundulus heteroclitus, held in live boxes were noted only in the weathered treatment systems.