Florence Lot

A case-control study of HIV seroconversion in health care workers after percutaneous exposure

BACKGROUND The average risk of human immunodeficiency virus (HIV) infection after percutaneous exposure to HIV-infected blood is 0.3 percent, but the factors that influence this risk are not well understood. METHODS We conducted a case-control study of health care workers with occupational, percutaneous exposure to HIV-infected blood. The case patients were those who became seropositive after exposure to HIV, as reported by national surveillance systems in France, Italy, the United Kingdom, and the United States. The controls were health care workers in a prospective surveillance project who were exposed to HIV but did not seroconvert. RESULTS Logistic-regression analysis based on 33 case patients and 665 controls showed that significant risk factors for seroconversion were deep injury (odds ratio= 15; 95 percent confidence interval, 6.0 to 41), injury with a device that was visibly contaminated with the source patients blood (odds ratio= 6.2; 95 percent confidence interval, 2.2 to 21), a procedure involving a needle placed in the source patients artery or vein (odds ratio=4.3; 95 percent confidence interval, 1.7 to 12), and exposure to a source patient who died of the acquired immunodeficiency syndrome within two months afterward (odds ratio=5.6; 95 percent confidence interval, 2.0 to 16). The case patients were significantly less likely than the controls to have taken zidovudine after the exposure (odds ratio=0.19; 95 percent confidence interval, 0.06 to 0.52). CONCLUSIONS The risk of HIV infection after percutaneous exposure increases with a larger volume of blood and, probably, a higher titer of HIV in the source patients blood. Postexposure prophylaxis with zidovudine appears to be protective.Background The average risk of human immunodeficiency virus (HIV) infection after percutaneous exposure to HIV-infected blood is 0.3 percent, but the factors that influence this risk are not well understood. Methods We conducted a case–control study of health care workers with occupational, percutaneous exposure to HIV-infected blood. The case patients were those who became seropositive after exposure to HIV, as reported by national surveillance systems in France, Italy, the United Kingdom, and the United States. The controls were health care workers in a prospective surveillance project who were exposed to HIV but did not seroconvert. Results Logistic-regression analysis based on 33 case patients and 665 controls showed that significant risk factors for seroconversion were deep injury (odds ratio = 15; 95 percent confidence interval, 6.0 to 41), injury with a device that was visibly contaminated with the source patients blood (odds ratio = 6.2; 95 percent confidence interval, 2.2 to 21), a procedure inv...

Risk factors for hepatitis C virus transmission to health care workers after occupational exposure: A European case-control study

BACKGROUND Factors that influence the risk for HCV infection after occupational exposure to hepatitis C virus (HCV) have not yet been determined. The objective of this study was to assess potential risk factors for Hepatitis C seroconversion after occupational exposure to HCV. METHODS We conducted a European matched case-control study from 01/01/1991 through 31/12/ 2002. Cases were Health Care Workers (HCWs) who were HCV seronegative at the time of exposure, sustained a documented exposure to HCV, and present documented HCV seroconversion temporally associated with the exposure. Controls-HCWs had a documented exposure to HCV, were HCV seronegative at the time of exposure, and remained so at least 6 months later. Controls were matched to cases for the center and the time period of the exposure occurrence. RESULTS 60 cases and 204 controls were included. All cases were exposed to HCV-infected materials through percutaneous injuries. Those for whom information was available (61.6%) were exposed to viremic source patients. Multivariate conditional logistic regression analysis, in which HCV viral load was not introduced because of missing values, identified needle placed in the source patients vein or artery (Odds Ratio [OR]=100.1; 95% Confidence Interval [CI]=7.3-1365.7), deep injury (OR=155.2; 95%CI=7.1-3417.2), and HCWs gender (M vs. F: OR=3.1; 95%CI=1.0-10.0) as risk factors for HCV infection. In univariate unmatched analysis the risk of HCV transmission was increased 11-fold (C195%=1.1-114.1) in HCWs exposed to sources with a viral load>6 log10 copies/mL when compared to sources with a HCV viral load<4 log10 copies/mL. CONCLUSION The risk of HCV transmission after percutaneous exposure increases with a larger volume of blood, and, a higher titer of HCV in the source patients blood. The role of HCWs gender need to be further investigated. The results of this study have important implications for counselling and follow-up of HCWs after exposure.

Probable Transmission of HIV from an Orthopedic Surgeon to a Patient in France

Since the beginning of the AIDS epidemic, transmission of HIV from an infected health care worker to patients has been reported only once (1). To better quantify the risk that patients may become infected with HIV during invasive procedures, several investigations of patients exposed to an infected health care worker have been undertaken. In 1995, the Centers for Disease Control and Prevention (CDC) summarized the results of all published and unpublished investigations (2). Of 22 171 patients tested who were treated by 51 HIV-infected health care workers, 113 HIV-positive patients were reported, but epidemiologic and laboratory follow-up did not show that a health care worker was the source of HIV infection for any of the patients. We report on an epidemiologic investigation that supports transmission of HIV from an orthopedic surgeon to a patient during surgery. Methods History In July 1995, a French medical newspaper reported that an orthopedic surgeon practicing in the hospital of Saint-Germain-en-Laye (a public hospital in the Paris suburbs) had been accidentally infected with HIV while performing surgery 12 years earlier. In September 1995, the surgeon asked the hospital director to screen all of his former patients and informed the press of his request. In October 1995, the French Ministry of Health offered HIV testing to patients who had been operated on by the surgeon. An epidemiologic investigation was initiated that included review of the surgeons medical history, assessment of the surgeons practices and comparison with the practices of other surgeons and the infection-control personnel of the hospital, and identification and HIV testing of patients on whom the surgeon had performed an invasive procedure. Medical Evaluation of the Surgeon An infectious disease specialist and a medical epidemiologist interviewed the surgeon by using an unpublished CDC questionnaire (Risk ascertainment questionnaire for adult/adolescent HIV/AIDS cases reported without risk information, 1994). The questionnaire inquires about all known avenues of exposure to HIV to determine the most likely date of infection. A medical epidemiologist interviewed the surgeons health care providers to obtain the surgeons medical history. Evaluation of the Surgeons Practices Two infection-control physicians interviewed the surgeon to review operating room practices. Information was collected on blood exposures, surgical procedures, and infection-control precautions. The surgeons practices were compared with those of all of the other surgeons of the hospital (1 orthopedic surgeon and 11 other surgeons), who were interviewed by using the same questionnaire. In addition, the disinfection and sterilization procedures of the operating room were evaluated by interviewing an operating room nurse, the head nurse, and the pharmacist in charge of sterilizing the surgical and medical devices of the hospital. Identification and Evaluation of Patients at Risk An information center with a toll-free telephone number was set up at the hospital on 19 October 1995. The center handled telephone calls, identified and notified patients at risk, managed consultations, and received exposed patients for counseling and HIV testing. Patients at risk were defined as those on whom the surgeon had performed an invasive procedure during the period from the presumed date of his infection until he ceased practicing surgery. An invasive procedure was defined as a procedure involving an open wound or incision in the skin. Patients at risk were identified from surgical reports that the surgeon had signed as the responsible surgeon or co-surgeon and that specified an invasive procedure. Patients were sent a letter informing them they had been operated on by the unnamed HIV-infected surgeon. The letter discussed the low risk for HIV infection in this context and suggested that patients make an appointment with their physician or call the toll-free telephone number. For patients whose letters were returned as undeliverable, attempts were made to obtain the current address from the hospitals admission department and, if necessary, from the French national health insurance system. A second letter was sent to all nonresponders. The content of this letter was more specific; it offered free counseling and HIV testing at the information center. At the hospital laboratory, enzyme-linked immunosorbent assay was used to test serum samples for antibody to HIV-1. Patients who wanted to be tested by their own physician were asked to report the results to the information center. All general practitioners and private laboratories of the district were asked to report the HIV serology results of exposed patients who had been tested outside the hospital laboratory (with the consent of the patients). A computerized database of all patients at risk was created with the agreement of the French National Committee on Information and Privacy. Procedures were classified into three categories according to the risk for exposure: major surgery (prosthetic joint replacement, spine procedures, open reduction of fracture, ligamentoplasty of knee or ankle, amputation, osteotomy, or arthrotomy), medium surgery (hardware removal), and minor surgery (arthroscopy, resection of cysts, exploration of cuts, whitlow, punctures, and operations on metatarsi or metacarpi). If a patient had undergone more than one procedure within the same category of exposure, the date of the most recent procedure was taken as the date of exposure. For patients who had undergone procedures within different categories, the date of the procedure that carried the highest risk for exposure was taken as the date of exposure. With the agreement of the French National Committee on Information and Privacy, all untested patients were matched by date of birth, first name, and initial of last name to the national mandatory AIDS case registry to identify any former patients who were reported to have AIDS and had no other identified risk factors. HIV-Positive Patient and Molecular Investigation An infectious disease specialist interviewed the one identified HIV-positive patient about risk factors for HIV infection and a potential seroconversion syndrome. The patients surgical record, the operating room register, and the ward logbook were reviewed for possible patient exposure to the blood of the surgeon or another health care worker. The national reference center for virology and immunology of human retroviruses performed molecular analysis to compare viral sequences from the surgeon and the HIV-positive patient. At different dates, blood samples were collected with consent from the surgeon (November 1995 and September 1996) and his patient (February 1996). After amplification by using polymerase chain reaction, the env and gag sequences from the viral genomes were cloned and sequenced. Phylogenetic analysis was performed by using the software package Phylip (Department of Genetics, University of Washington, Seattle, Washington). Pairwise evolutionary distances were estimated by using the Kimura two-parameter model. Phylogenetic trees were constructed by the neighbor-joining and maximum likelihood methods. The phylogenetic relations among the sequences obtained from the surgeon and the patient were determined. Representative sequences of different HIV-1 subtypes were used for comparison. Details of these methods have been published elsewhere. (3). Results Medical Evaluation of the Surgeon The 53-year-old surgeon received a diagnosis of AIDS in March 1994, when he presented with HIV encephalopathy. At that time, his CD4 cell count was 46 cells/mL. He had stopped performing surgery in October 1993 because of depression, but he was not tested for HIV at that time. At the time of the interview in January 1996, the surgeon did not present with any further neurologic disorders and had been receiving triple therapy (zidovudine, dideoxycytidine, and ritonavir) for 10 months. The surgeon was married, had only heterosexual contacts with his wife, denied using injection drugs, never received a blood transfusion, and traveled only to various European countries. He had been vaccinated against hepatitis B, tested negative for hepatitis C, and had no history of sexually transmitted diseases. He reported that in May 1983, he had a needlestick injury while operating on a patient who had received multiple transfusions and whose HIV serologic status was not known. This patient later died. Thirty days after the needlestick, the surgeon developed a febrile illness characterized by fatigue, weight loss, and rashsymptoms consistent with the HIV seroconversion syndromethat resulted in interruption of his normal activities. In 1988, the surgeon had diarrhea lasting 4 months. Stool cultures tested positive only for Aeromonas hydrophila. In November 1992, viral pneumonitis was diagnosed. Bronchoscopy showed reactive mucous membranes; biopsy and bronchoalveolar lavage were not done. Evaluation of the Surgeons Practices The surgeon had been practicing as an orthopedic specialist in the same hospital since 1970. He had never received specific training about universal precautions but was aware of their principles. The surgeon reported frequent opportunities for blood exposures, as well as frequent actual blood exposures (Table). For example, he often tightened suture wires with his fingers and sometimes tied sutures with the needle still attached. Although his fingers sometimes directed the needle, he did not report digital palpation of the needle tip while suturing. However, he did report using digital palpation of the needle tip during placement of bone pins. He used metallic wires for tendinous sutures and mentioned that his fingers were sometimes confined with sharp objects in a blind cavity. Table. Surgical Techniques and Occupational Blood Exposure of the HIV-Infected Surgeon and the Other Surgeons of the Hospital The surgeon reported that percutaneous injuries

Monitoring the Dynamics of the HIV Epidemic Using Assays for Recent Infection and Serotyping among New HIV Diagnoses: Experience after 2 Years in France

BACKGROUND New tools to better monitor dynamics of human immunodeficiency virus (HIV) transmission are needed. METHODS National surveillance of newly HIV diagnoses included the collection of dried serum spots to identify both recent infections (<6 months) and HIV serotypes. Multivariate analyses were used to identify factors associated with recent infection and infection with non-B subtypes. RESULTS Between 2003 and March 2005, 7902 new HIV diagnoses were reported. The overall proportion of recent infections was 24.9% (95% confidence interval, 23.8%-26.0%) and was highest among men who have sex with men (MSM; 46%). Recent infection was associated with being an MSM, <30 years old, of French nationality, and living in Paris. Nearly half of newly HIV-1 diagnoses were with non-B subtypes. The highest proportion of non-B infections was reported among African heterosexual persons (81%), but important proportions were reported among French heterosexual persons (34%) and MSM (12%). Being infected by a non-B subtype was independently associated with being African, <30 years old, heterosexual, and living in Paris. The proportion of HIV-2 infection was 1.9%, and 11 cases of HIV-1 group O infection were identified, mainly among West Africans. CONCLUSIONS There is evidence of high levels of HIV transmission among MSM in France and transmission of non-B subtypes within the indigenous French population.

European recommendations for the management of healthcare workers occupationally exposed to hepatitis B virus and hepatitis C virus

Exposure prevention is the primary strategy to reduce the risk of occupational bloodborne pathogen infections in healthcare workers (HCW). HCWs should be made aware of the medicolegal and clinical relevance of reporting an exposure, and have ready access to expert consultants to receive appropriate counselling, treatment and follow-up. Vaccination against hepatitis B virus (HBV), and demonstration of immunisation before employment are strongly recommended. HCWs with postvaccinal anti-HBs levels, 1-2 months after vaccine completion, >10 mIU/mL are considered as responders. Responders are protected against HBV infection: booster doses of vaccine or periodic antibody concentration testing are not recommended. Alternative strategies to overcome non-response should be adopted. Isolated anti-HBc positive HCWs should be tested for anti-HBc IgM and HBV-DNA: if negative, anti-HBs response to vaccination can distinguish between infection (anti-HBs >50 mUI/ml 30 days after 1st vaccination: anamnestic response) and false positive results(anti-HBs >10 mUI/ml 30 days after 3rd vaccination: primary response); true positive subjects have resistance to re-infection. and do not need vaccination The management of an occupational exposure to HBV differs according to the susceptibility of the exposed HCW and the serostatus of the source. When indicated, post-exposure prophylaxis with HBV vaccine, hepatitis B immunoglobulin or both must be started as soon as possible (within 1-7 days). In the absence of prophylaxis against hepatitis C virus (HCV) infection, follow-up management of HCV exposures depends on whether antiviral treatment during the acute phase is chosen. Test the HCW for HCV-Ab at baseline and after 6 months; up to 12 for HIV-HCV co-infected sources. If treatment is recommended, perform ALT (amino alanine transferase) activity at baseline and monthly for 4 months after exposure, and qualitative HCV-RNA when an increase is detected.

Phylogenetic Analyses Indicate an Atypical Nurse-to-Patient Transmission of Human Immunodeficiency Virus Type 1

ABSTRACT A human immunodeficiency virus (HIV)-negative patient with no risk factor experienced HIV type 1 (HIV-1) primary infection 4 weeks after being hospitalized for surgery. Among the medical staff, only two night shift nurses were identified as HIV-1 seropositive. No exposure to blood was evidenced. To test the hypothesis of a possible nurse-to-patient transmission, phylogenetic analyses were conducted using two HIV-1 genomic regions (pol reverse transcriptase [RT] and env C2C4), each compared with reference strains and large local control sets (57 RT and 41 C2C4 local controls). Extensive analyses using multiple methodologies allowed us to test the robustness of phylogeny inference and to assess transmission hypotheses. Results allow us to unambiguously exclude one HIV-positive nurse and strongly suggest the other HIV-positive nurse as the source of infection of the patient.

Prevalence of HIV-2 and HIV-1 group O infections among new HIV diagnoses in France: 2003-2006.

French national surveillance of new HIV diagnoses included the collection of dried serum spots to identify HIV serotypes. Between January 2003 and June 2006, 10 184 new diagnoses were reported. The proportions of HIV-2 and HIV-1 group O infections were 1.8 and 0.1%, respectively. Most of these cases occurred in patients infected through heterosexual contact and originated from the corresponding endemic areas. Three cases of HIV-2 infections were reported in non-African men having sex with men.

Preliminary results from the new HIV surveillance system in France

In addition to AIDS surveillance, data on HIV infection are necessary to better follow the dynamics of the epidemic. We report the first results of Frances mandatory anonymous HIV notification system, which is linked to a virological surveillance of recent HIV infections and of circulating HIV types, groups and subtypes. HIV notifications are initiated by microbiologists who create an anonymous code of patients identity. Clinicians complete the notification form with epidemiological and clinical data. Notifications are sent to the local health authorities and passed to the Institut de Veille Sanitaire (InVS).

Cost-effectiveness of HIV post-exposure prophylaxis in France.

ObjectiveTo assess the cost-effectiveness of HIV post-exposure prophylaxis (PEP) in France. MethodsWe used a decision tree to evaluate, from a societys perspective, the cost of PEP per quality-adjusted life-year (QALY) saved. We used 1999–2003 PEP surveillance data and literature-derived data on per event transmission probabilities, PEP efficacy and quality of life with HIV. HIV prevalence and lifetime cost of HIV/AIDS management in the HAART era were derived from French studies. We assumed that mean life expectancy in full health was 65 years among uninfected individuals and that the mean survival time after HIV infection was 22.5 years. The costs of PEP drugs and follow-up were derived from the French public sector. A 3% annual rate was used to discount future costs and effects. ResultsDuring 1999–2003, PEP was prescribed to 8958 individuals (heterosexual sex: 47.6%; homosexual sex: 28.4%; occupational exposure: 23.4%; drug injection: 0.6%); of those, 2143 were exposed to a known HIV-infected source. PEP was estimated to prevent 7.7 infections and saved 64.5 QALY at a net cost of &U20AC;5.7 million, resulting in an overall cost-effectiveness ratio of &U20AC;88 692 per QALY saved. PEP was cost saving for 4.4% of cases and cost effective (< &U20AC;50 000 per QALY) in a further 11.3% of cases. In contrast, 72 and 52% of prescriptions had a cost-effectiveness ratio exceeding &U20AC;200 000 and &U20AC;2 millions, respectively, per QALY saved. ConclusionOverall, the French PEP programme is only moderately cost effective. PEP guidelines should be revised to target high-risk exposures better.

Post-Exposure Prophylaxis of HIV Infection in Healthcare Workers: Recommendations for the European Setting

The European Commission funded a project for the standardisation of the management of occupational exposures to HIV/blood-borne infections and antiretroviral post-exposure prophylaxis (PEP) in Europe. Within this project, the following recommendations and rationale were formulated by experts representative of participating countries. Based on assessment of the exposure, material, and source characteristics, PEP should be started as soon as possible with any triple combination of antiretrovirals approved for the treatment of HIV-infected patients; initiation is discouraged after 72 hours Rapid HIV testing of the source could reduce inappropriate PEP. HIV testing should be performed at baseline, 4, 12, and 24 weeks, with additional clinical and laboratory monitoring of adverse reactions and potential toxicity at week 1 and 2. HIV resistance tests in the source and direct virus assays in the exposed HCW are not recommended routinely. These easy-to-use recommendations seek to maximise PEP effect while minimising its toxicity and inappropriate use.