RESUMO
BACKGROUND: Experimental findings have suggested that human cytomegalovirus (HCMV) infection of tumor cells may exert oncomodulatory effects that enhance tumor malignancy. However, controversial findings have been published on the presence of HCMV in malignant tumors. Here, we present the first study that systematically investigates HCMV infection in human nervous system tumors by highly sensitive immunohistochemistry in correlation with the HCMV serostatus of the patients. METHODS: Immunohistochemical and quantitative PCR-based methods to detect different HCMV antigens and genomic HCMV DNA were optimized prior to the investigation of pathological samples. Moreover, the pathological results were matched with the HCMV serostatus of the patients. RESULTS: HCMV immediate-early, late, and pp65 antigens could be detected in single cells from HCMV strain Hi91-infected UKF-NB-4 neuroblastoma cells after 1:1024 dilution with noninfected UKF-NB-4 cells. Genomic HCMV DNA could be detected in copy numbers as low as 430 copies/mL. However, we did not detect HCMV in tumors from a cohort of 123 glioblastoma, medulloblastoma, or neuroblastoma patients. Notably, we detected nonspecifically positive staining in tumor tissues of HCMV seropositive and seronegative glioblastoma patients. The HCMV serostatus of 67 glioblastoma patients matched the general epidemiological prevalence data for Western countries (72% of female and 57% of male glioblastoma patients were HCMV seropositive). Median survival was not significantly different in HCMV seropositive versus seronegative glioblastoma patients. CONCLUSIONS: The prevalence of HCMV-infected tumor cells may be much lower than previously reported based on highly sensitive detection methods.
Assuntos
Neoplasias Encefálicas/diagnóstico , Infecções por Citomegalovirus/diagnóstico , Citomegalovirus/isolamento & purificação , Glioblastoma/diagnóstico , Neuroblastoma/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Neoplasias Encefálicas/epidemiologia , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/virologia , Estudos de Casos e Controles , Citomegalovirus/genética , Infecções por Citomegalovirus/epidemiologia , Infecções por Citomegalovirus/mortalidade , Infecções por Citomegalovirus/virologia , DNA Viral/genética , Feminino , Seguimentos , Glioblastoma/epidemiologia , Glioblastoma/mortalidade , Glioblastoma/virologia , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neuroblastoma/epidemiologia , Neuroblastoma/mortalidade , Neuroblastoma/virologia , Prognóstico , Reação em Cadeia da Polimerase em Tempo Real , Estudos Soroepidemiológicos , Taxa de SobrevidaRESUMO
BACKGROUND: Intensive chemotherapy in children with cancer results in long-term impairment of humoral immunity. Whereas most studies to date focused on children with acute lymphoblastic leukemia (ALL), little data have been published on patients suffering from Hodgkin disease or from solid tumors. We therefore analyzed the loss of protective immunity (defined as immunity at the time of diagnosis and lack of immunity after completion of therapy) against vaccine-preventable diseases in children treated for various malignancies. METHODS: Children and adolescents <21 years of age at diagnosis and treated between 2001 and 2010 for various malignancies in the Department of Pediatric Hematology and Oncology, University of Frankfurt, were included in the retrospective chart review. Antibody levels against measles, mumps, rubella and varicella-zoster-virus (VZV) were routinely assessed at the time of diagnosis and within 12 months after completion of therapy. RESULTS: The study population consisted of 195 children (122 male); 80 patients had ALL, 15 acute myelogenous leukemia (AML), 18 non-Hodgkin lymphoma (NHL), 22 Hodgkin disease, and 60 various solid tumors. Overall, 27%, 47%, 19%, and 17% of the patients lost their humoral immunity against measles, mumps, rubella, and VZV, respectively. The risk of losing protective antibody titers depended on age with a higher risk in younger children. The loss of protective humoral immunity occurred significantly more often in patients with ALL compared to patients with any other underlying malignant disease (hematological malignancies such AML and NHL, Hodgkin disease or solid tumors). CONCLUSIONS: Our data demonstrate that a significant number of children lose pre-existing humoral immunity against measles, mumps, rubella, and VZV after completion of chemotherapy. This loss occurs more often in children with ALL than in children with AML, solid tumors and Hodgkin disease. Our results underline the need for post-chemotherapy revaccination of childhood cancer survivors.
Assuntos
Anticorpos Antivirais/sangue , Antineoplásicos/efeitos adversos , Imunidade Humoral , Neoplasias/imunologia , Adolescente , Antineoplásicos/uso terapêutico , Varicela/imunologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Sarampo/imunologia , Caxumba/imunologia , Neoplasias/tratamento farmacológico , Estudos Retrospectivos , Rubéola (Sarampo Alemão)/imunologia , Adulto JovemRESUMO
BACKGROUND: Immune response rates following influenza vaccination are often lower in HIV-infected individuals. Low vitamin D levels were correlated with weak immune response in cancer patients and are known to be lower in HIV-infected patients. METHODS: Diagnostic study to determine immune response against the H1N1v component after a single, intramuscular dose of the 2010/11 seasonal, trivalent influenza vaccine (TIV) in adult HIV-infected and healthy controls scheduled for influenza vaccination (ClinicalTrials.gov Identifier: NCT01017172). Influenza A/H1N1 antibody titers (AB) were determined before and 21 days after vaccination by hemagglutination inhibition assay. RESULTS: Immune response was not different between HIV-infected patients (n = 36) and healthy controls (n = 42) who were previously naïve to the H1N1v component of the TIV. Comparing HIV-infected patients (n = 55) and healthy controls (n = 63) who had received 1 or 2 doses of an AS03 adjuvanted H1N1 vaccine in the previous winter season (2009/10), seroconversion rate and the geometric mean AB titer after TIV of the HIV-infected patients were more than twice as high compared to healthy controls. This difference was mainly driven by the 2-dose schedule for HIV patients in 2009/10. Vitamin D levels were lower in HIV patients but did not correlate with immune response. CONCLUSION: HIV-infected patients who had received 1 or 2 doses of an adjuvanted H1N1 vaccine in the previous year (2009/10) had a significant higher seroconversion rate following TIV as compared to healthy controls, indicating a stronger memory cell response due to the 2-dose schedule.
Assuntos
Síndrome da Imunodeficiência Adquirida/imunologia , HIV-1 , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Adulto , Anticorpos Antivirais/sangue , Feminino , Humanos , Vacinas contra Influenza/administração & dosagem , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Virologic response-monitoring is essential for determining therapy duration in patients with chronic hepatitis C virus (HCV) infection. This is usually performed using highly sensitive HCV-RNA assays. However, HCV-RNA assays are time-consuming, expensive and require highly trained personnel. Quantitative determination of HCV core-antigen (HCVAg) levels may be used to supplement treatment monitoring. OBJECTIVES: The clinical utility of the ARCHITECT HCV Ag assay (Abbott Diagnostics) for response-guided therapy was investigated. STUDY DESIGN: We analyzed serum from 160 patients with HCV genotype 1 infection who had been treated with peg-interferon alfa-2b/ribavirin. HCVAg levels were determined at baseline, weeks 1, 2, 4 and 12. HCVAg levels were compared to those obtained with HCV-RNA assays: VERSANT HCV Quantitative 3.0 (bDNA) and Qualitative (TMA, both Siemens Healthcare) assay and the Abbott RealTime HCV assay (ART; Abbott Diagnostics). RESULTS: Baseline HCVAg levels correlated well with HCV-RNA as assessed by bDNA (r=0.91; p<0.0001) and ART (r=0.92; p<0.0001), respectively. Patients with undetectable HCVAg levels at week 1 had a 90.9% probability (positive predictive value) to achieve a rapid virologic response (HCV-RNA undetectable at week 4) based on TMA and 86.4% based on ART, respectively. Patients with less than 1 log(10) reduction in HCVAg between baseline and week 12 had a 90% probability (negative predictive value) to achieve a nonresponse (<2 log(10) decline in HCV-RNA between baseline and week 12) based on bDNA and 100% based on ART, respectively. CONCLUSIONS: Determination of HCVAg may be useful for antiviral response-monitoring in patients with HCV genotype 1 infection.
Assuntos
Antivirais/uso terapêutico , Monitoramento de Medicamentos/métodos , Antígenos da Hepatite C/sangue , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Imunoensaio/métodos , Adulto , Idoso , Feminino , Genótipo , Hepacivirus/genética , Hepatite C Crônica/sangue , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/uso terapêutico , Valor Preditivo dos Testes , RNA Viral/sangue , Proteínas Recombinantes/uso terapêutico , Ribavirina/uso terapêutico , Proteínas do Core Viral/sangueRESUMO
Infection with human herpes virus 8 (HHV8) is associated with development of Kaposi's sarcoma (KS); therefore also known as KS-associated herpes virus. KS is closely associated with human immunodeficiency virus (HIV) infection, and consequently HHV8 seroprevalence is higher in HIV-infected compared to HIV-negative patients. Currently, KS is rarely seen in clinical practice, which might be a consequence of an optimized anti-HIV treatment leading to an improved immunological status, or alternatively of a decrease in HHV8 prevalence. To determine the prevalence of HHV8 antibodies in HIV-positive compared to HIV-negative patients from the University Hospital Frankfurt/Main, Germany, and to compare our results with previously published data to illustrate trends in the spread of infection. Hundred serum samples each of HIV-positive and HIV-negative patients were analyzed for HHV8 antibodies by using an IgG immunofluorescence test. The overall HHV8 seroprevalence was 16% with no statistically significant gender-specific differences; however, the distribution between the HIV-infected patients and the HIV-negative control group was significantly different (30 and 2%, respectively). The highest rate of seroprevalence in HIV-infected patients was detected at the age of 40-49 (42%) and the lowest rate at the age of 20-29 years (16.6%). In comparison with formerly conducted studies, our data clearly showed an increase in the HHV8 seroprevalence in HIV-infected patients, both in men and women. Therefore, we conclude that the low rate of clinical KS is associated with an improved immunological status due to an optimized anti-HIV therapy.
Assuntos
Anticorpos Antivirais/sangue , Infecções por HIV/epidemiologia , HIV/imunologia , Herpesvirus Humano 8/imunologia , Sarcoma de Kaposi/epidemiologia , Adulto , Idoso , Feminino , Alemanha/epidemiologia , HIV/patogenicidade , Infecções por HIV/complicações , Infecções por HIV/imunologia , Infecções por HIV/virologia , Herpesvirus Humano 8/patogenicidade , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Sarcoma de Kaposi/complicações , Sarcoma de Kaposi/imunologia , Sarcoma de Kaposi/virologia , Estudos Soroepidemiológicos , Adulto JovemRESUMO
Seroconversion rates following influenza vaccination in patients with hematologic malignancies after hematopoietic stem cell transplantation (HSCT) are known to be lower compared to healthy adults. The aim of our diagnostic study was to determine the rate of seroconversion after 1 or 2 doses of a novel split virion, inactivated, AS03-adjuvanted pandemic H1N1 influenza vaccine (A/California/7/2009) in HSCT recipients (ClinicalTrials.gov Identifier: NCT01017172). Blood samples were taken before and 21 days after a first dose and 21 days after a second dose of the vaccine. Antibody (AB) titers were determined by hemagglutination inhibition assay. Seroconversion was defined by either an AB titer of ≤ 1:10 before and ≥ 1:40 after or ≥ 1:10 before and ≥ 4-fold increase in AB titer 21 days after vaccination. Seventeen patients (14 allogeneic, 3 autologous HSCT) received 1 dose and 11 of these patients 2 doses of the vaccine. The rate of seroconversion was 41.2% (95% confidence interval [CI] 18.4-67.1) after the first and 81.8% (95% CI 48.2-97.7) after the second dose. Patients who failed to seroconvert after 1 dose of the vaccine were more likely to receive any immunosuppressive agent (P = .003), but time elapsed after or type of HSCT, age, sex, or chronic graft-versus-host disease was not different when compared to patients with seroconversion. In patients with hematologic malignancies after HSCT the rate of seroconversion after a first dose of an adjuvanted H1N1 influenza A vaccine was poor, but increased after a second dose.
Assuntos
Anticorpos Antivirais/sangue , Transplante de Células-Tronco Hematopoéticas , Vírus da Influenza A Subtipo H1N1 , Vacinas contra Influenza/administração & dosagem , Pandemias , Adulto , Fatores Etários , Idoso , Anticorpos Antivirais/imunologia , Doença Crônica , Feminino , Doença Enxerto-Hospedeiro/sangue , Doença Enxerto-Hospedeiro/imunologia , Humanos , Vacinas contra Influenza/imunologia , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Transplante Autólogo , Transplante Homólogo , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/imunologiaRESUMO
Given that a significant proportion of children with acute lymphoblastic leukaemia (ALL) lose immune protection to tetanus, diphtheria, and poliomyelitis, revaccination is indicated after chemotherapy. Our randomized pilot study comparing different revaccination schedules suggests that children with ALL might be revaccinated with non-live vaccines as early as 3 months after chemotherapy.
Assuntos
Imunização Secundária/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Vacinas de Produtos Inativados/administração & dosagem , Adolescente , Anticorpos Antibacterianos/biossíntese , Anticorpos Antivirais/biossíntese , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Cápsulas Bacterianas/administração & dosagem , Cápsulas Bacterianas/imunologia , Criança , Pré-Escolar , Toxoide Diftérico/administração & dosagem , Toxoide Diftérico/imunologia , Feminino , Vacinas Anti-Haemophilus/administração & dosagem , Vacinas Anti-Haemophilus/imunologia , Humanos , Tolerância Imunológica/efeitos dos fármacos , Esquemas de Imunização , Imunoglobulinas/sangue , Subpopulações de Linfócitos/efeitos dos fármacos , Subpopulações de Linfócitos/imunologia , Masculino , Projetos Piloto , Vacinas contra Poliovirus/administração & dosagem , Vacinas contra Poliovirus/imunologia , Toxoide Tetânico/administração & dosagem , Toxoide Tetânico/imunologia , Vacinas de Produtos Inativados/imunologia , Adulto JovemRESUMO
BACKGROUND: The objective of this study was to assess the seroprevalence of coinfecting viruses and Treponema pallidum (T. pallidum) in a cohort of 205 antiretrovirally treated HIV-infected individuals (152 females and 53 males, aged: 19-71 years) in rural Lesotho. Furthermore agent-specific immune responses were investigated by analyzing antibody titers against herpes simplex virus type 2 (HSV-2) and against T. pallidum. METHODS: Serum samples were tested by enzyme-linked immunosorbent assay for antibodies against HSV-2, cytomegalovirus, hepatitis A, B, and C viruses, and T. pallidum. RESULTS: Seroprevalences (95% confidence intervals) were found to be 100% (98.5%-100%) for anti-cytomegalovirus, 98.5% (95.7%-99.7%) for anti-hepatitis A virus, 35.5% (28.9%-42.6%) for anti-HBc, 5.5% (2.8%-9.6%) for hepatitis B surface antigen, and 0.5% (0.0%-2.8%) for anti-hepatitis C virus. Only 78.5% (72.2%-84.0%) were anti-HSV-2 positive and 29.0% (22.8%-35.8%) had antibodies against T. pallidum. Only anti-HSV-2 titers showed gender- and CD4 cell-count dependent differences: females with >500 CD4 cells/microL had an average anti-HSV-2 titer of 446 compared with males of 398 AU/mL (not significant), but in those with 250 to 500 CD4 cells/microL, there was a significant difference with a mean titer of 467 compared to 302 AU/mL in males (P = 0.001). CONCLUSIONS: A high seroprevalence of CMV, HAV, and HBV was found in both genders. One-third of the patients had been exposed to HBV and T. pallidum. The generally high HSV-2 prevalence showed gender- and CD4 cell count-dependent differences in HSV-2 antibody titer.
Assuntos
Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Anticorpos Antibacterianos/sangue , Anticorpos Antivirais/sangue , Infecções por HIV/epidemiologia , Sífilis/epidemiologia , Viroses/epidemiologia , Infecções Oportunistas Relacionadas com a AIDS/etiologia , Infecções Oportunistas Relacionadas com a AIDS/imunologia , Adulto , Idoso , Contagem de Linfócito CD4 , Feminino , HIV/imunologia , Infecções por HIV/complicações , Infecções por HIV/imunologia , Infecções por HIV/virologia , Herpes Genital/complicações , Herpes Genital/epidemiologia , Herpes Genital/imunologia , Herpes Genital/virologia , Herpesvirus Humano 2/imunologia , Humanos , Lesoto/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Soroepidemiológicos , Fatores Sexuais , Sífilis/complicações , Sífilis/imunologia , Sífilis/microbiologia , Treponema pallidum/imunologia , Viroses/complicações , Viroses/imunologia , Viroses/virologiaRESUMO
BACKGROUND: An improved test version of the Abbott ARCHITECT anti-hepatitis C virus (HCV) test became available at the end of 2005. STUDY DESIGN: We compared the new test version with the Ortho Vitros anti-HCV test by evaluating 2034 serum samples in parallel on both systems under routine laboratory conditions. Discordant samples were tested in the Inno-LIA HCV Score assay as well as in the RIBA HCV 3.0. RESULTS: Of the 2034 samples 140 (6.9%) yielded positive and 1856 (91.2%) negative results in both assays. We observed discordant results in 38 samples (1.9%). All discrepant samples showed a low S/CO ratio of 1.0-6.9 (mean 2.8) in the Ortho assay and of 1.3-3.0 (mean 1.96) in the ARCHITECT assay. As expected, most of them could not be confirmed by immunoblot testing. Comparison of the results of the two immunoblots (Inno-LIA and RIBA) revealed a great variability in test results. CONCLUSIONS: This study represents the first comparative evaluation of the modified version of the Abbott ARCHITECT anti-HCV assay in comparison with the Ortho Vitros anti-HCV test. Under routine laboratory testing, we observed good overall concordance between the two assays and no evidence that one assay shows more false-reactive or negative results than the other.
Assuntos
Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/sangue , Hepatite C/diagnóstico , Kit de Reagentes para Diagnóstico , Feminino , Hepatite C/imunologia , Humanos , Imunoensaio/métodos , Immunoblotting , Medições Luminescentes , Programas de Rastreamento , Valor Preditivo dos Testes , Gravidez , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Virologia/métodosRESUMO
BACKGROUND: The most common causes for diarrhea both in children and adults are of viral genesis. Thereby rota-, noro-, adeno-, and astroviruses are mentioned in descending order. The diagnosis of these frequently nosocomial infections can easily result from virus antigen detection of stool samples. MATERIAL AND METHODS: In this retrospective epidemiologic survey of the number of annual stool samples of patients with gastroenteritis, the frequency scale of each virus as well as seasonal aspects, the genital arrangement, and age distribution of mainly patients of the University Hospital Frankfurt/Main and some other health institutions in the closer surrounding were analyzed during the period 2001-2006. RESULTS: The proficiency rate of viral investigations amounts to about 10-20%. Similar to previous years, the rotavirus infection poles the most frequent cause of infantile gastroenteritis in Germany. The second place is taken by another adeno- or by norovirus. Astrovirus infections have been seen more rarely in the last 3 years. CONCLUSION: In accordance with recent surveys in other regions it is shown that nowadays the main part of infectious gastroenteritis is caused by norovirus type 2 and--in opposition to rotavirus--elderly people are preferentially affected.
Assuntos
Gastroenterite/virologia , Infecções por Adenovirus Humanos/diagnóstico , Infecções por Adenovirus Humanos/epidemiologia , Infecções por Adenovirus Humanos/virologia , Adolescente , Adulto , Antígenos Virais/análise , Infecções por Astroviridae/diagnóstico , Infecções por Astroviridae/epidemiologia , Infecções por Astroviridae/virologia , Infecções por Caliciviridae/diagnóstico , Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/virologia , Criança , Pré-Escolar , Infecção Hospitalar/diagnóstico , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/virologia , Estudos Transversais , Diarreia Infantil/epidemiologia , Diarreia Infantil/virologia , Fezes/química , Gastroenterite/diagnóstico , Gastroenterite/epidemiologia , Alemanha , Humanos , Lactente , Mamastrovirus , Pessoa de Meia-Idade , Norovirus , Infecções por Rotavirus/diagnóstico , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Estações do AnoRESUMO
BACKGROUND: Medical students come into contact with infectious diseases early on their career. Immunity against vaccine-preventable diseases is therefore vital for both medical students and the patients with whom they come into contact. METHODS: The purpose of this study was to compare the medical history and serological status of selected vaccine-preventable diseases of medical students in Germany. RESULTS: The overall correlation between self-reported medical history statements and serological findings among the 150 students studied was 86.7 %, 66.7 %, 78 % and 93.3 % for measles, mumps, rubella and varicella, conditional on sufficient immunity being achieved after one vaccination. Although 81.2 % of the students' medical history data correlated with serological findings, significant gaps in immunity were found. CONCLUSION: Our findings indicate that medical history alone is not a reliable screening tool for immunity against the vaccine-preventable diseases studied.
Assuntos
Anticorpos Antivirais/sangue , Vacina contra Sarampo-Caxumba-Rubéola/imunologia , Estudantes de Medicina/estatística & dados numéricos , Vacinação/estatística & dados numéricos , Adulto , Feminino , Alemanha , Humanos , Técnicas Imunoenzimáticas , Masculino , Sarampo/imunologia , Anamnese , Pessoa de Meia-Idade , Caxumba/imunologia , Rubéola (Sarampo Alemão)/imunologia , Autorrevelação , Testes Sorológicos , Inquéritos e QuestionáriosRESUMO
OBJECTIVE: Health care workers (HCWs) are exposed to bloodborne pathogens, especially hepatitis B (HBV), hepatitis C (HCV), and human immunodeficiency virus (HIV) through job-related risk factors like needlestick, stab, scratch, cut, or other bloody injuries. Needlestick injuries can be prevented by safer devices. METHODS: The purpose of this study was to investigate the frequency and causes of needlestick injuries in a German university hospital. Data were obtained by an anonymous, self-reporting questionnaire. We calculated the share of reported needlestick injuries, which could have been prevented by using safety devices. RESULTS: 31.4% (n = 226) of participant HCWs had sustained at least one needlestick injury in the last 12 months. A wide variation in the number of reported needlestick injuries was evident across disciplines, ranging from 46.9% (n = 91/194) among medical staff in surgery and 18.7% (n = 53/283) among HCWs in pediatrics. Of all occupational groups, physicians have the highest risk to experience needlestick injuries (55.1%-n = 129/234). Evaluating the kind of activity under which the needlestick injury occurred, on average 34% (n = 191/561) of all needlestick injuries could have been avoided by the use of safety devices. Taking all medical disciplines and procedures into consideration, safety devices are available for 35.1% (n = 197/561) of needlestick injuries sustained. However, there was a significant difference across various medical disciplines in the share of needlestick injuries which might have been avoidable: Pediatrics (83.7%), gynecology (83.7%), anesthesia (59.3%), dermatology (33.3%), and surgery (11.9%). In our study, only 13.2% (n = 74/561) of needlestick injuries could have been prevented by organizational measures. CONCLUSION: There is a high rate of needlestick injuries in the daily routine of a hospital. The rate of such injuries depends on the medical discipline. Implementation of safety devices will lead to an improvement in medical staff's health and safety.