Accidental Needlestick Exposure Research Articles

Syringe type and drug injector risk for HIV infection: a case study in Texas

Studies of accidental needlestick exposure to blood containing human immunodeficiency virus (HIV) have shown that the volume of blood in an exposure is a strong predictor of subsequent infection. Illicit drug injectors, a group at elevated risk for HIV transmission, use syringes manufactured in two styles, one of which (the integral cannula type) retains substantially less blood after intravenous use than the other (the detachable needle type). In this report, we examine some of the factors associated with use of syringes with detachable needles among drug injectors in San Antonio, Texas using data from epidemiological surveys, ethnographic studies, and historical observations. We compare personal history of syringe type use with HIV serostatus in a sample of 501 active drug injectors interviewed and screened for HIV in 1997–1998. Ninety-nine percent of these respondents reported that they currently used only integral cannula syringes, but 13% had used a syringe with a detachable needle within the past 2 years, and 37% had used one in their lifetime. Only 9% had ever used one ⩾20 times in a year. Hispanic (Mexican American) respondents were significantly less likely than other ethnic groups to have ever used a detachable needle syringe. HIV seroprevalence was <1% among heterosexual injectors who had never used a detachable needle syringe compared to 4% among those who had used one ( p<0.05).

Determinants of viral clearance and persistence during acute hepatitis C virus infection.

The virological and immunological features of hepatitis C virus (HCV) infection were studied weekly for 6 months after accidental needlestick exposure in five health care workers, four of whom developed acute hepatitis that progressed to chronicity while one subject cleared the virus. In all subjects, viremia was first detectable within 1-2 weeks of inoculation, 1 month or more before the appearance of virus-specific T cells. The subject who cleared the virus experienced a prolonged episode of acute hepatitis that coincided with a CD38+ IFN-gamma- CD8+ T cell response to HCV and a small reduction in viremia. Subsequently, a strong CD4+ T cell response emerged and the CD8+ T cells became CD38- and started producing IFN-gamma in response to HCV, coinciding with a rapid 100,000-fold decrease in viremia that occurred without a corresponding surge of disease activity. Chronic infection developed in two subjects who failed to produce a significant T cell response and in two other subjects who initially mounted strong CD4+ T cell responses that ultimately waned. In all subjects, viremia was higher at the peak of acute hepatitis than it was when the disease began, and the disease improved during the viremia. These results provide the first insight into the host-virus relationship in humans during the incubation phase of acute HCV infection, and they provide the only insight to date into the virological and immunological characteristics of clinically asymptomatic acute HCV infection, the commonest manifestation of this disease. In addition, the results suggest that the vigor and quality of the antiviral T cell response determines the outcome of acute HCV infection, that the ability of HCV to outpace the T cell response may contribute to its tendency to persist; that the onset of hepatitis coincides with the onset of the CD8+ T cell response, that disease pathogenesis and viral clearance are mediated by different CD8+ T cell populations that control HCV by both cytolytic and noncytolytic mechanisms, and that there are different pathways to viral persistence in asymptomatic and symptomatic acute HCV infection.

Accidental Needlesticks in the Phlebotomy Service of the Department of Laboratory Medicine and Pathology at Mayo Clinic Rochester

To determine the change in accidental needlestick rates in the Phlebotomy Service at Mayo Clinic Rochester and to identify safety practices implemented from 1983 through 1996. We retrospectively reviewed yearly Phlebotomy Service accidental needlestick rates from 1983 through 1996. Interviews were conducted with representatives of the Infection Control Committee and the management team for the Phlebotomy Service, and minutes of meetings of these two groups were reviewed to identify implemented safety improvements that may have had an effect on accidental needlestick exposures. Accidental needlestick exposures in the Phlebotomy Service declined from a high of 1.5/10,000 venipunctures to 0.2/10,000 venipunctures. Several safety improvements were made during that time, including the implementation of a one-handed recapping block, change to single-use evacuated tube holders, increased number and improved locations of disposal containers for needles, implementation of resheathing needles and retractable capillary puncture devices, discontinuation of the practice of changing needles before inoculation of blood culture bottles, increased emphasis on safety for new and experienced phlebotomists, and improved exposure reporting tools. We believe that the decrease in our accidental needlestick exposure rate is correlated with the changes in education, practices, and products that we have implemented.

Detection of infectious human immunodeficiency type 1 virus in discarded syringes of intravenous drug users.

Detection of infectious human immunodeficiency type 1 virus in discarded syringes of intravenous drug users.

High prevalence of antibodies to hepatitis C virus in three haemodialysis centres in south-western Poland

We assessed the prevalence of anti-hepatitis C virus (anti-HCV) antibodies and markers of hepatitis B virus (HBV) infection in patients of three haemodialysis centres before initiating anti-HBV vaccinations. Of the 94 patients, 39 (41.5%) were anti-HCV positive (+) and 81 (86.2%) were anti-hepatitis B core antigen (HBc) positive. There was a high rate of anti-HBc positivity among anti-HCV (+) patients (92.3%), although the presence of anti-HCV and anti-HBc antibodies were not significantly related to each other. Multiple blood transfusions (> 5 units) was a risk factor for development of HCV infection (P < 0.02), while none of our patients admitted intravenous drug abuse. Although 53.8% of anti-HCV (+) patients have had moderate serum alanine aminotransferase (ALT) elevations during the study period, none has had considerable liver disease, nor did the increased ALT correlate with the presence of anti-HCV. Only two of 17 staff members participating in the survey were anti-HCV (+), though almost every one gave a history of accidental needlestick exposure. All the study subjects were human immunodeficiency virus (HIV) negative. Our results, obtained with the second-generation, highly specific enzyme immunoassay and verified by the immunoblot assay for anti-HCV antibodies, support a recent suggestion that earlier reports might have underestimated the true prevalence of anti-HCV antibodies in haemodialysis patients.

Needlestick Injury Associated With Venipuncture

To the Editor. —Accidental needlestick exposure to human immunodeficiency virus (HIV) during venipuncture has been attributed to recapping or disposal of needles, 1 inexperience, 2 and failure to take recommended precautions. 3 Herein we report that experienced personnel are at risk of needlestick exposure even under apparently low-risk conditions. Over the past 5 years, we have been studying the psychological and behavioral effects of HIV testing and counseling. 4 Before engaging in our study, three nurse venipuncturists received extensive training in the procedures and recommended precautions for avoiding needlestick injury. The nurses were aware that there was no urgency in obtaining the blood samples either at entry or at follow-up assessments. They also knew that subjects were at high risk for HIV infection: of 702 adults, 247 (35%) were HIV positive. Nevertheless, after the nurses had worked in the study for at least 6 months, four accidental needlestick exposures occurred.

Determination of HIV-1 Status of Discarded Sharps: Polymerase Chain Reaction Using Minute Quantities of Blood

To the Editor.— As the number of individuals infected with human immunodeficiency virus type 1 (HIV-1) grows, the potential for accidental needle-stick injuries with contaminated blood increases. Strict adherence to infectioncontrol guidelines may limit this hazard. However, needle-stick injuries by discarded sharps present a special problem if the patient source of the needle is unknown. Report of a Case.— A nurse in an outpatient medical office had an accidental needle-stick exposure with a discarded angiocatheter. Many catheterization procedures had been performed, and the patient source was unknown. On the day of the accident, the angiocatheter was submitted to our laboratory and approximately 60 μL of serum was aspirated from the clotted blood in the hub of the needle. The sample was reactive to HIV-1 by Western immunoblot. 1 The needle was flushed with 300 μL of phosphate-buffered saline, and the eluant was processed for DNA extraction and polymerase

Factors Influencing Postexposure Immunprophylaxis of Hepatitis B Virus Infection With Hepatitis B Immune Globulin: High Deoxyribonucleic Acid Polymerase Activity in the Inocula of Unsuccessful Cases

Hepatitis B immune globulin was given intramuscularly to 102 staff members of a dialysis unit within 48 h after the accidental needlestick exposure to blood containing hepatitis B surface antigen (HBsAg). Hepatitis B virus (HBV) infection developed in 11 of 56 persons (20%) who had been exposed to blood containing hepatitis B e antigen (HBeAg). Among 56 HBeAg-positive inocula, HBsAg-associated deoxyribonucleic acid polymerase activity in the 11 inocula that transmitted HBV infection was significantly higher than that in the remaining 45 inocula that did not (log counts per minute 3.27 +/- 0.57 vs. 2.09 +/- 1.19, p less than 0.001). These 11 HBeAg-positive inocula revealed higher hemagglutination titers of HBsAg (geometric mean 13.5 +/- 1.4 vs. 11.2 +/- 3.2, p less than 0.001). The receptor for polymerized human serum albumin was detected significantly more often in the inocula that transmitted HBV infection than those that did not (10/11 vs. 24/45, p less than 0.05). Based on the results obtained, the failure in protecting all of those exposed to HBeAg-positive blood would be attributable to a high concentration of HBV in some HBeAg-positive inocula and the inability of intramuscular injection to raise a protective level of antibody in the circulation immediately.