A possible mode of transfer of infection by syringes used for mass inoculation

Infection Prevention and Control in the Podiatric Medical Setting. Challenges to Providing Consistently Safe Care

Unsafe practices are an underestimated contributor to the disease burden of bloodborne viruses. Outbreaks associated with failures in basic infection prevention have been identified in nonhospital settings with increased frequency in the United States during the past 15 years, representing an alarming trend and indicating that the challenge of providing consistently safe care is not always met. As has been the case with most medical specialties, public health investigations by state and local health departments, and the Centers for Disease Control and Prevention, have identified some instances of unsafe practices that have placed podiatric medical patients at risk for viral, bacterial, and fungal infections. All health-care providers, including podiatric physicians, must make infection prevention a priority in any setting in which care is delivered.

US outbreak investigations highlight the need for safe injection practices and basic infection control

Current understanding of viral hepatitis transmission in United States health care settings indicates progress over the past several decades with respect to the risks from transfusions or blood products. Likewise, risks to health care providers from sharps injuries and other blood and body fluid exposures have been reduced as a consequence of widespread hepatitis B vaccination and the adoption of safer work practices. Increasing recognition of outbreaks involving patient-to-patient spread of hepatitis B and hepatitis C virus infections, however, has uncovered a disturbing trend. This article highlights the importance of basic infection control and the need for increased awareness of safe injection practices.

Knowledge of HIV survival on skin-piercing instruments among young adults in Nyanza Province, Kenya

In countries with generalized HIV epidemics, people may be exposed to blood-borne HIV at their home as well as during health care and cosmetic services. We asked young adults from the Luo and Kisii ethnic groups in Nyanza Province, Kenya, how long HIV survives in blood and how to clean skin-piercing instruments. Only 21% thought that HIV could survive more than an hour in dry conditions (although it can survive for days), and only 24% thought it could survive more than a week in wet conditions (although it can survive more than four weeks). The Kisii, with lower HIV prevalence, were more knowledgeable than the Luo about HIV survival. Survey participants reported that barbers and other service providers often cleaned instruments by wiping with alcohol or bleach, a practice which does not reliably inactivate HIV. People we interviewed, at risk from blood-borne HIV, did not know enough to protect themselves.

Outbreak of hepatitis C virus infection during sclerotherapy of varicose veins: long-term follow-up of 196 patients (4535 patient-years)

BACKGROUND/AIMS

The aim of this study was to describe the natural history of a HCV infection outbreak in 196 patients who had sclerotherapy by a same physician and to confirm patient-to-patient transmission using phylogenetic analysis in a large series of patients.

METHODS

Demographic information included clinical and biological parameters. Fibrosis evaluation was performed using liver biopsy or transient elastography. Follow-up was maintained until death, or the end of the observation period. In order to determine if the virus had been transmitted between the HCV genotype 2 patients, sequence analysis was undertaken of a part of the NS5b region of the genomes in samples of patients.

RESULTS

The mean duration of follow-up was 23.1+/-6.7 years (4535 patient-years). In patients with fibrosis evaluation, 55.7% had no or mild fibrosis and 44.3% had significant fibrosis. No patient died from HCV-related disease. Nucleotide sequence analysis of a part of the NS5b region revealed that patients were all infected with the same HCV subtype (genotype 2d). The most evident feature of the tree is the clustering of all patients involved in the outbreak without any unrelated isolates.

CONCLUSION

This study emphasizes the risk for nosocomial spread of HCV during intravenous therapy.

Efficiency of human immunodeficiency virus transmission through injections and other medical procedures: evidence, estimates, and unfinished business

OBJECTIVE

To estimate the transmission efficiency of human immunodeficiency virus (HIV) through medical injections and other invasive procedures.

DESIGN

We searched our own files and Medline (from 1966-2004, using the keywords ["iatrogenic" or "nosocomial" or "injections"] and "HIV") for reports of iatrogenic outbreaks worldwide, except outbreaks traced to receipt of contaminated blood or blood products. We also analyzed information from a case-control study of percutaneous exposures to healthcare workers.

SETTING

Worldwide healthcare settings. EVENTS: We identified 8 iatrogenic outbreaks that met our study criteria; published information from 4 outbreaks was sufficient to estimate transmission efficiency.

RESULTS

From the 4 documented iatrogenic outbreaks, we estimated that 1 iatrogenic infection occurred after 8-52 procedures involving HIV-infected persons. Although only 0.3% of healthcare workers seroconvert after percutaneous exposure, a case-control study reported that deep injuries and other risk factors collectively increased seroconversion risk by as much as 50 times. Laboratory investigations demonstrate HIV survival through time and various rinsing regimens. We estimate that the transmission efficiency in medical settings with no or grossly insufficient efforts to clean equipment ranges from 0.5% to 3% for lower risk procedures (eg, intramuscular injections) and from 10% to 20% or more for high-risk procedures. Efforts to clean equipment, short of sterilization, may cut the transmission efficiency by 0%-100%. Procedures that contaminate multidose vials may accelerate transmission efficiency.

CONCLUSION

To achieve better estimates of the transmission efficiency for a range of medical procedures and settings, investigations of iatrogenic outbreaks should be accorded high priority.

Epidemiological and phylogenetic evidence for patient-to-patient hepatitis C virus transmission during sclerotherapy of varicose veins

The aim of this study was to provide evidence for patient-to-patient nosocomial hepatitis C virus (HCV) transmission during sclerotherapy of varicose veins. Forty-three patients who had evidence of current infection by genotype 2 HCV have had sclerotherapy by the same physician. Based on this observation, a detailed epidemiological questionnaire on risk factors for HCV in genotype 2 infected patients was conducted. Seventeen sequences in the hypervariable region 1 (HVR1) of the HCV genome obtained from 17 HCV RNA positive patients with a past history of sclerotherapy, were compared with 17 sequences derived from genotype 2 patients with no past history of sclerotherapy, and with 25 sequences sampled from GenBank. Two hundred seven genotype 2 HCV infected patients were included. The main risk factors for HCV infection were transfusion (n = 76), drug use (n = 6), and sclerotherapy of varicose veins (n = 62 including 43 (20.8%) by the same physician), other or unknown (n = 76). These sclerotherapy sessions were carried out in the 1980s for many years. Five of these 43 patients had jaundice within a few weeks after a sclerotherapy session. Sequence analysis of HVR1 from 17 patients who had sclerotherapy by the same physician revealed that they were all infected with HCV genotype 2c. The phylogenetic tree indicated clustering of the patients with a past history of sclerotherapy. The method by which infection was likely to have been transmitted was probably the use of a single vial for multiple patients. This study provides strong evidence that sclerotherapy of varicose veins is a risk factor for HCV infection.

Risk of transmission of hepatitis B virus through childhood immunization in northwestern China

Transmission of bloodborne pathogens by means of unsafe injection practices is a significant public health problem in developing countries. Although the overall proportion for immunization is low among injections, unsafe immunization practices affect mostly infants, a population with an increased likelihood of becoming hepatitis B virus carriers. This study estimated the prevalence of unsafe injection among vaccinators working at the peripheral level in northwestern China and the risk of HBV infections among infant vaccinees, and analyzed factors contributing to the most prevalent unsafe practice: the reuse of a non-sterilized reusable syringe among infants. A knowledge-attitude-practice survey was conducted in which 180 peripheral vaccinators selected by multi-stage cluster sampling in each of four provinces and one autonomous region completed a self-administered questionnaire. The lack of observational data for assessing the validity of the self-reported practices made the study prone to systematic respondent bias that may have skewed the results towards underestimation of unsafe practices. The minimum estimate of the percentage of peripheral vaccinators reusing a syringe and/or needle without sterilization between infants was 7.2-55.0%, whereas the percentage of those disposing of used disposable syringes and needles inappropriately was 8.9-23.3% by province. According to a model-based estimate, the annual number of HBV infections among 100,000 fully immunized children due to unsafe immunization injection was at least 135-3120. An insufficient supply of syringes and the attitude to justify reuse were significantly associated with the unsafe reuse of a reusable syringe in most part of the area studied. Introduction of auto-disable syringes may contribute to curb the unsafe practices, but the development of safe collection and disposal procedures for used syringes and needles is prerequisite. Sufficient supply of equipment as well as training, supervision, and monitoring targeting specifically on the risk behaviors and concerned attitudes are essential for behavior changes among the vaccinators.

The transmission of hepatitis virus by routine immunization procedures

The returns relating to naval personnel who were reported to the Admiralty to have acquired non-surgical jaundice between 1944 and 1947 were examined.

Where the dates of onset of illness and of inoculation were available, the numbers who developed the illness within 11–40 days of inoculation were greater than the numbers to be expected if there was no association between the dates of onset of illness and the dates of inoculation. During 1945 the observed numbers were also greater than the expected numbers when 41–70 days intervened between inoculation and the illness.

The interpretation and practical implications of the findings are discussed.

This paper is published by kind permission of the Medical Director General of the Navy, Surgeon Vice-Admiral Sir Alexander Ingleby-Mackenzie.

I am indebted to Dr F. O. MacCallum for his continued interest and for invaluable suggestions; to Dr J. O. Irwin for scrutinizing the script; to Miss H. M. Ferres who applied the statistical tests to the figures in Table 1; to Surgeon Commander M. A. Rugg-Gunn, Royal Navy, for the information about the ratings' pay books, and to Senior Commissioned Wardmaster J. L. T. Burns, Royal Navy, and Sick Berth Petty Officer (L) D. E. Lee, Royal Navy, who tabulated the numerical data.

Transmission of hepatitis C in a pharmacologic study

OBJECTIVE

To describe an outbreak of hepatitis C in a clinical research study.

DESIGN

Observational study.

SETTING

Tertiary-care hospital.

PATIENTS

Healthcare workers who volunteered to be subjects in a study of the metabolic effects of inhaled and oral corticosteroids who were unwittingly exposed to hepatitis C virus (HCV).

METHODS

Epidemiological investigation and serological analyses.

RESULTS

One chronic carrier of HCV was identified. Four fellow workers volunteering in the studies became infected with HCV, with 96% homology among strains. There was no evidence of spread from infected healthcare workers to patients on whom they had performed arterial punctures (2 of 214 positive, unrelated to each other and to the outbreak strain).

CONCLUSION

Infection control standards in clinical research must be maintained vigorously to prevent transmission of blood-borne pathogens such as HCV.

Glucose-6-phosphate dehydrogenase deficiency and sulfadimidin acetylation phenotypes in Egyptian oases

Screening of 1315 males from two Egyptian oases for glucose-6-phosphate dehydrogenase deficiency (G-6PD) found an incidence of 5.9%. The rate of acetylation of sulfadimidin was also studied, and a bimodal distribution was found with 73% rapid acetylators. There is a correlation between high frequency of G-6PD deficiency and high frequency of slow acetylation rate.