Tuberculosis among health care workers

To assess the annual risk for latent tuberculosis infection (LTBI) among health care workers (HCWs), the incidence rate ratio for tuberculosis (TB) among HCWs worldwide, and the population-attributable fraction of TB to exposure of HCWs in their work settings, we reviewed the literature. Stratified pooled estimates for the LTBI rate for countries with low (<50 cases/100,000 population), intermediate (50-100/100,000 population), and high (>100/100,000 population) TB incidence were 3.8% (95% confidence interval [CI] 3.0%-4.6%), 6.9% (95% CI 3.4%-10.3%), and 8.4% (95% CI 2.7%-14.0%), respectively. For TB, estimated incident rate ratios were 2.4 (95% CI 1.2-3.6), 2.4 (95% CI 1.0-3.8), and 3.7 (95% CI 2.9-4.5), respectively. Median estimated population-attributable fraction for TB was as high as 0.4%. HCWs are at higher than average risk for TB. Sound TB infection control measures should be implemented in all health care facilities with patients suspected of having infectious TB.     

Nosocomial transmission of Mycobacterium tuberculosis found through screening for severe acute respiratory syndrome--Taipei, Taiwan, 2003

The emergence of severe acute respiratory syndrome (SARS) has highlighted the importance of hospital infection-control programs. Prevention of Mycobacterium tuberculosis transmission also requires effective infection control in health-care facilities. In Taipei, Taiwan, an area with moderate to high incidence of tuberculosis (TB) (50-74 cases per 100,000 population), health-care workers (HCWs) are at increased risk for M. tuberculosis (Taiwan Center for Disease Control, unpublished data, 2002). In April 2003, SARS-related screening in a hospital in Taipei resulted in the detection of suspected TB among HCWs. This report summarizes how SARS screening led to the discovery of 60 cases of TB. HCWs in Taiwan should remain vigilant for cases of TB so persons suspected of having TB are evaluated and treated promptly.     

Tuberculosis in health care workers in Malawi.

Although sub-Saharan Africa has the highest rates of tuberculosis (TB) and human immunodeficiency virus (HIV) infection in the world, the rates of TB amongst its health care workers (HCWs) are poorly documented. We therefore conducted a country-wide investigation. All district/government and mission hospitals in Malawi that diagnose and care for TB patients were visited in order to obtain information on hospital-based HCWs and their incidence of TB in 1996. Hospital TB case loads, country-wide TB notification numbers and national population estimates for 1996 were obtained, which enabled TB case notification rates to be calculated. In 1996, 108 (3.6%) of 3042 HCWs from 40 hospitals were registered and treated for TB: 22 with smear-positive pulmonary TB (PTB), 40 with smear-negative PTB and 46 with extrapulmonary TB. The overall case fatality rate was 24%. Compared with the adult general population aged > or = 15 years, the relative risk [95% confidence interval (CI)] in HCWs of all types of TB was 11.9 [9.8-14.4], of smear-positive PTB 5.9 [3.9-9.0], of smear-negative PTB 13.0 [9.5-17.7] and of extrapulmonary TB 18.4 [13.8-24.6], P < 0.05. The 1996 hospital TB case load ranged from 29 to 915: there were no cases of TB in HCWs in hospitals whose case load was < or = 100 patients, while the TB case rate among HCWs was similar in hospitals with annual case loads of 101-300 or > 300. The annual risk of TB was high among all categories of HCW, especially clinical officers. This study shows a high rate of TB in HCWs in Malawi, and emphasizes the need for practical and affordable control measures for the protection of HCWs from TB in low-income countries.     

Risk of tuberculous infection among healthcare workers in a tertiary-care hospital in Ankara, Turkey.

OBJECTIVE: To determine risk factors for tuberculin skin test (TST) positivity among healthcare workers (HCWs). DESIGN: Two-step TST was performed in 2002. SETTING: Tertiary-care hospital in Ankara, Turkey. PARTICIPANTS: A sample of 491 hospital HCWs were included. Information related to demographics, profession, work duration, department, and individual and family history of tuberculosis (TB) was obtained by a structured questionnaire. RESULTS: Four hundred eight (83%) had two-step TST positivity. On multivariate analysis, male physicians (relative risk [RR], 1.5; 95% confidence interval [CI95], 1.23-1.69; P = .001), nurses (RR, 1.5; CI95, 1.29-1.66; P = .005), radiology technicians (RR, 1.7; CI95, 1.35-1.73; P = .002), laboratory technicians (RR, 1.6; CI95, 1.3-1.74; P = .007), and male housekeepers (RR, 1.6; (HCWs). CI95, 1.38-1.7; P < .001) had a higher risk than did female physicians. Among laboratory technicians, radiology technicians had the highest TST positivity (85%). HCWs working for less than 1 year (RR, 0.8; CI95, 0.72-0.98; P = .027) had a lower risk of infection. The HCWs having bacille Calmette-Guerin vaccination (RR, 1.12; CI95, 1.08-1.45) had higher TST positivity. CONCLUSION: Male physicians, nurses, and laboratory technicians had increased risk of Mycobacterium tuberculosis infection in this setting, but community exposure likely accounted for most infections.     

Local problems, local solutions: improving tuberculosis control at the district level in Malawi

OBJECTIVE: To examine the causes of a low cure rate at the district level of a tuberculosis (TB) control programme and to formulate, implement, and evaluate an intervention to improve the situation. METHODS: The study setting was Mzuzu (population 60,000), where the annual smear-positive pulmonary TB incidence was 160 per 100,000 and the human immunodeficiency virus (HIV) seroprevalence was 67% among TB patients. There is one TB treatment unit, but several other organizations are involved with TB control. An examination of case-holding activities was carried out, potential areas for improvement were identified, and interventions performed. FINDINGS: In 1990-91, the cure rate was 24% among smear-positive cases (29% among survivors to end of treatment). Problems identified included a fragmented TB control programme; inadequate training and supervision; suboptimal recording of patients' addresses; and nonadherence to national TB control programme protocols. These problems were addressed, and in 1992-93 the cure rate rose to 68% (relative risk (RR) = 2.85 (95% confidence interval (CI) = 1.63, 4.96)) and to 92% among survivors to the end of treatment (RR = 3.12 (95% CI = 1.84, 5.29)). High cure rates are therefore achievable despite high HIV prevalence. CONCLUSIONS: Simple, inexpensive, local programmatic interventions can dramatically improve TB case holding. This study demonstrates the need for evaluation, training, and supervision at all levels of the programme.     

Factors associated with tuberculin reactivity in two general hospitals in Mexico.

OBJECTIVE: To identify risk factors associated with tuberculin reactivity in healthcare workers (HCWs). DESIGN: Cross-sectional survey of tuberculin reactivity (2 TU of purified protein derivative (PPD) RT23, using the Mantoux two-step test). SETTING: Two general hospitals located in a region with a high prevalence of tuberculosis and high bacille Calmette-Guerin (BCG) coverage. PARTICIPANTS: Volunteer sample of HCWs. RESULTS: 605 HCWs were recruited: 71.2% female; mean age, 36.4 (standard deviation [SD], 8.2) years; 48.9% nurses, 10.4% physicians, 26.8% administrative personnel; mean time of employment, 10.9 (SD, 6.7) years. PPD reactivity (> or =10 mm) was found in 390 (64.5%). Multivariate analysis revealed an association of tuberculin reactivity with occupational exposure in the hospital: participation in autopsies (odds ratio [OR], 9.3; 95% confidence interval [CI95], 2.1-40.5; P=.003.), more than 1 year of employment (OR, 2.4; CI95, 1.1-5.0; P=.02), work in the emergency or radiology departments (OR, 2.0; CI95, 1.03-3.81; P=.04), being physicians or nurses (OR, 1.5; CI95, 1.04-2.11; P=.03), age (OR, 1.04; CI95, 1.02-1.07 per year of age; P<.001), and BCG scar (OR, 2.1; CI95, 1.2-3.4; P=.005). CONCLUSIONS: Although the studied population has a high baseline prevalence of tuberculosis infection and high coverage of BCG vaccination, nosocomial risk factors associated with PPD reactivity were identified as professional risks; strict early preventive measures must be implemented accordingly.     

Nutritional risk factors for tuberculosis among adults in the United States, 1971-1992

The risk of developing tuberculosis (TB) may be related to nutritional status. To determine the impact of nutritional status on TB incidence, the authors analyzed data from the First National Health and Nutrition Examination Survey (NHANES I) Epidemiologic Follow-up Study (NHEFS). NHANES I collected information on a probability sample of the US population in 1971-1975. Adults were followed up in 1982-1992. Incident TB cases were ascertained through interviews, medical records, and death certificates. TB incidences were compared across different levels of nutritional status after controlling for potential confounding using proportional hazards regression appropriate to the complex sample design. TB incidence among adults with normal body mass index was 24.7 per 100,000 person-years (95% confidence interval (CI): 13.0, 36.3). In contrast, among persons who were underweight, overweight, and obese, estimated TB incidence rates were 260.2 (95% CI: 98.6, 421.8), 8.9 (95% CI: 2.2, 15.6), and 5.1 (95% CI: 0.0, 10.5) per 100,000 person-years, respectively. Adjusted hazard ratios were 12.43 (95% CI: 5.75, 26.95), 0.28 (95% CI: 0.13, 0.63), and 0.20 (95% CI: 0.07, 0.62), respectively, after controlling for demographic, socioeconomic, and medical characteristics. A low serum albumin level also increased the risk of TB, but low vitamin A, thiamine, riboflavin, and iron status did not. A population's nutritional profile is an important determinant of its TB incidence.     

Nosocomial transmission of Mycobacterium tuberculosis from an extrapulmonary site.

OBJECTIVE: To assess the extent of nosocomial transmission and risk factors associated with tuberculin skin test (TST) conversions among healthcare workers (HCWs) exposed to a patient with genitourinary Mycobacterium tuberculosis. DESIGN: Retrospective cohort study of exposed HCWs. SETTING: A 275-bed community hospital in Middle Tennessee. PARTICIPANTS: A total of 128 exposed HCWs and the index patient, who required drainage of a prostatic abscess and bilateral orchiectomy and expired after a 27-day hospitalization. Disseminated tuberculosis was diagnosed at autopsy. METHODS: Contact tracing was performed on exposed HCWs. Logistic regression was used to identify independent risk factors associated with TST conversion. RESULTS: A total of 128 HCWs were exposed to the index patient. There was no evidence of active pulmonary tuberculosis throughout the patient's hospitalization; TST conversions occurred only among HCWs who were exposed to the patient during or after his surgical procedures. A total of 12 (13%) of 95 exposed HCWs who were previously nonreactive had newly positive TST: 6 of 28 nurses, 3 of 3 autopsy personnel, 2 of 17 respiratory therapists, and 1 of 12 surgical staff. By logistic regression, irrigation or packing of the surgical site was the only independent risk factor associated with TST conversion among nurses (odds ratio, 9; 95% confidence interval, 1.2-67; P=.03). CONCLUSION: Manipulation of infected tissues of the genitourinary tract can result in nosocomial transmission of tuberculosis.     

医务人员结核病相关知识与实施防护措施调查

目的了解综合性医疗机构医务人员结核病相关知识及职业防护的知晓情况。方法采用结核病防治知识问卷,对某综合医院临床科室医务人员进行结核病相关知识及职业防护行为的问卷调查。结果共收回有效问卷333份,医务人员对结核病相关知识的正确应答率为62.84%～93.09%;国家针对结核病政策方面的内容,医务人员正确应答率为59.52%～77.27%。医务人员中结核病相关知识知晓组与不知晓组职业防护措施实施率［（10.74%～79.34%）vs（10.38%～82.55%）］无明显差异（P＞0.05）,但知晓组每次参加医院组织的定期体检的实施率（92.56%）高于不知晓组（79.25%）,差异有统计学意义（P＜0.05）。结论 综合性医疗机构的医务人员应强化结核病相关知识培训,落实职业防护措施。     

Occupational tuberculosis in healthcare workers in sub-Saharan Africa: A systematic review

ABSTRACT

This article investigates the incidence, prevalence and factors associated with occupational tuberculosis (TB) in healthcare workers (HCWs) in sub-Saharan Africa (SSA). Studies were extracted from MEDLINE, PsycINFO, CINAHL, Cochrane Library, and SCOPUS databases following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement from inception to the 2^nd of June 2017. Twenty-one studies met the inclusion criteria. The median prevalence of latent TB infection in HCWS was 62% (IQR 22%) and the median incidence of TB disease was 3871/100,000 (IQR 9314/100,000). The risk factors associated with LTBI or active TB disease were workplace, history of contact with TB patients, and longer duration of employment. The findings of this review demonstrate that the risk of acquiring TB among HCWs in SSA is high. This may impact on the recruitment, longevity and retention of HCWs.     

Occupational health policies and practices related to tuberculosis in health care workers in KwaZulu-Natal,South Africa

Setting:

Three district hospitals in KwaZulu-Natal, South Africa, with specialized drug-resistant tuberculosis (TB) wards.

Objective:

To increase understanding of the implementation of occupational health (OH) and infection control (IC) guidelines for the prevention and control of TB among health care workers (HCWs).

Design:

An operational cross-sectional study conducted between July and September 2011, consisting of interviews with OH and IC nurses and chart review of OH medical records.

Results:

Although general national and provincial OH policies are in place, no specific OH policies exist for hospital settings. Two of three hospitals had a full-time OH nurse and all had a full-time IC nurse. All hospitals offered TB symptom screening; however, only 19% of HCWs were screened in 2010. TB incidence among HCWs was 1958 per 100 000 population in 2010. All hospitals offered HIV counseling and testing; however, only 22% of staff were tested across sites. Two hospitals offered isoniazid preventive therapy to HIV-positive staff and reassigned these staff to low TB risk areas.

Conclusions:

While OH policies and procedures are in place, implementation of these policies and procedures is inconsistent. This potentially places HCWs at risk of acquiring TB. These findings support the need for strengthening OH and IC services to prevent TB.     

Tuberculosis notifications in Australia, 2000.

Australia has one of the lowest incidences of tuberculosis (TB) in the world. The annual incidence rate has remained stable at between 5 and 6 per 100,000 population, since 1991. In 2000, there were 1,060 TB notifications in Australia, of which 1,004 were newly diagnosed cases and 56 were relapse cases. The corresponding incidence rate for new and relapsed TB was 5.2 and 0.3 cases per 100,000 population, respectively. The highest incidence of TB disease in Australia continues to be among the overseas-born (18.0 per 100,000 population) and Indigenous Australians (15.3 per 100,000 population). By contrast, the incidence of disease in the non-indigenous Australian-born population remains low (1.2 per 100,000 population).     

A survey of latent tuberculosis infection among laboratory healthcare workers in New York City.

OBJECTIVE: To determine the prevalence of positive tuberculin skin tests (TSTs), incidence of TST conversion, risk factors for positive TSTs, and history of active TB among HCWs in microbiology laboratories in New York City. DESIGN: Two-year survey from May 1999 to June 2001. SETTING: Nineteen microbiology laboratories. RESULTS: During the first year, interviews were conducted with 345 laboratory HCWs (mean, 18 HCWs per site; range, 2 to 51) to assess the prevalence of positive TSTs, but 3 (1%) could not recall their result and were excluded from further analyses. The mean age of the remaining 342 HCWs was 48 years; 68% (n = 233) were female, 54% (n = 183) received bacille Calmette-Guerin (BCG) vaccination, and 71% (n = 244) were foreign born. The prevalence of a positive TST was 57% (n = 196), but only 20% (n = 39) of the HCWs received isoniazid. The incidence of TST conversion in the second year of the study was 1% (1 of 108). Multivariate analysis identified age (odds ratio [OR] per year, 1.05; 95% confidence interval [CI95], 1.02-1.08), foreign birth (OR, 3.80; CI95, 1.98-7.28), BCG immunization (OR, 4.89; CI95, 2.72-8.80), and employment in a mycobacteriology laboratory (OR, 2.14; CI95, 1.25-3.68) as risk factors for a positive TST. Only one HCW had been treated for active TB. CONCLUSIONS: The prevalence of positive TSTs was high among laboratory HCWs, but the TST conversion rate was low. Higher rates of treatment for latent TB infection are desirable.     

Nosocomial tuberculosis exposure in an outpatient setting: evaluation of patients exposed to healthcare providers with tuberculosis.

OBJECTIVE: To evaluate the risk of tuberculosis (TB) transmission to patients potentially exposed to two healthcare providers who worked in outpatient settings for several weeks prior to being diagnosed with acid-fast bacilli smear-positive pulmonary TB. DESIGN: Potentially exposed patients were notified by letter and television reports of the recommended evaluation for TB infection or disease and availability of free screening at the hospital. Prevalence of infection in the screened patients and the incidence rate of TB over the subsequent 2 years were compared to those of a control group of unexposed outpatients. SETTING: An urban inner-city hospital. PATIENTS: 1,905 patients with potential exposure to the ill healthcare workers; 487 (25%) presented for evaluation. Controls consisted of 951 unexposed patients. RESULTS: 361 potentially exposed patients had their tuberculin test read; 97 (27%) had a purified protein derivative > or = 10 mm. In the comparison group, 148 (25%) of 600 with test readings had a > or = 10-mm reaction (risk ratio, 1.18; 95% confidence interval, 0.86-1.60). In multivariate analysis, male gender, non-white race, and older age were significantly associated with a positive tuberculin test; exposure was not. No TB cases were identified during screening. Two years after the exposure, 7 TB cases had been reported to the state registry among 1,905 potentially exposed patients (184 cases/100,000 person-years) versus 4 cases in the comparison group of 951 (210 cases/100,000 person-years). CONCLUSIONS: Evaluation of patients exposed to healthcare workers with TB disease in ambulatory settings of an inner-city hospital revealed no evidence of transmission of Mycobacterium tuberculosis due to the exposure.     

Improving hand sensibility in vibration induced neuropathy: A case-series

Introduction

Results of systematic screening of healthcare workers (HCWs) for tuberculosis (TB) with the tuberculin skin test (TST) and interferon-γ release assays (IGRA) in a Portuguese hospital from 2007 to 2010 are reported.

Methods

All HCWs are offered screening for TB. Screening is repeated depending on risk assessment. TST and QuantiFERON Gold In-Tube (QFT) are used simultaneously. X-ray is performed when TST is > 10 mm, IGRA is positive or typical symptoms exist.

Results

The cohort comprises 2,889 HCWs. TST and IGRA were positive in 29.5%, TST-positive but IGRA-negative results were apparent in 43.4%. Active TB was diagnosed in twelve HCWs - eight cases were detected during screening and four cases were predicted by IGRA as well as by TST. However, the progression rate in IGRA-positive was higher than in TST-positive HCWs (0.4% vs. 0.2%, p-value 0.06).

Conclusions

The TB burden in this cohort was high (129.8 per 100,000 HCWs). However, the progression to active TB after a positive TST or positive IGRA was considerably lower than that reported in literature for close contacts in low-incidence countries. This may indicate that old LTBI prevails in these HCWs.     

Analysis of risk factors for laboratory-acquired brucella infections

The aim of the study was to determine the risk factors for acquiring brucella infection among healthcare workers (HCWs). The study was performed in Ankara Numune Education and Research Hospital, Turkey, before the introduction of Biosafety III measures. A questionnaire was given to HCWs, who were at risk of brucella infection. Twelve HCWs with brucella infection were detected, an incidence of 8% per employee-year. A multivariate analysis of risk factors in seven of the cases and 48 control HCWs was performed. Male physicians were found to be associated with a higher risk of acquiring brucella infection [odds ratio, 25.3; confidence interval (CI), 2.3-283.7; P=0.008]. Using gloves was found to be protective (odds ratio, 0.02; CI, 0.008-0.4; P=0.017).     

Trends in tuberculosis incidence--United States, 2006

In 2006, a total of 13,767 tuberculosis (TB) cases (4.6 per 100,000 population) were reported in the United States, representing a 3.2% decline from the 2005 rate. This report summarizes provisional 2006 TB incidence data from the National TB Surveillance System and describes trends since 1993. The TB rate in 2006 was the lowest recorded since national reporting began in 1953, but the rate of decline has slowed since 2000. The average annual percentage decline in the TB incidence rate decreased from 7.3% per year during 1993-2000 (95% confidence interval [CI] = 6.9%-7.8%) to 3.8% during 2000-2006 (CI = 3.1%-4.5%). Foreign-born persons and racial/ethnic minority populations continue to be affected disproportionately by TB in the United States. In 2006, the TB rate among foreign-born persons in the United States was 9.5 times that of U.S.-born persons. The TB rates among blacks, Asians, and Hispanics were 8.4, 21.2, and 7.6 times higher than rates among whites, respectively. The slowing of the decline in the overall national TB rate and the inability to effectively address persistent disparities in TB rates between U.S.-born and foreign-born persons and between whites and racial/ethnic minority populations threaten progress toward the goal of eliminating TB in the United States. In 1989, CDC and the Advisory Committee for the Elimination of Tuberculosis issued a strategic plan for the elimination of TB, setting an interim target case rate of 3.5 per 100,000 population by 2000 and ultimately the elimination of TB (i.e., <1 case per 1 million population) in the United States by 2010.     

In-hospital contact investigation among health care workers after exposure to pulmonary tuberculosis in an intermediate tuberculosis prevalence area: A prospective study

We carried out in-hospital contact investigations of patients with pulmonary tuberculosis and analyzed the prevalence of latent tuberculosis infection (LTBI) among health care workers (HCWs) after TB exposure. A prospective study was conducted of 872 HCWs who were exposed to 55 index cases diagnosed with active pulmonary TB. HCWs after TB exposure were evaluated both TST and chest X-ray at the time of enrollment and 12 weeks after exposure; 625 HCWs (71.6%) underwent both initial assessments; 41 HCWs (6.6%) had a positive TST result. After 12 weeks, 71.1% of HCWs with initial negative TST (n = 415) underwent a second assessment. Ten HCWs had TST conversion. One HCW (0.2%) developed active pulmonary TB. In multivariable analysis, age over 30 years was associated with TST conversion (p = .02). Point prevalence of latent TB was 6.6%, and incidence of LTBI was estimated as 2.4 per 100 HCWs. Strict infection control measures should be emphasized in intermediate TB-burden, BCG-vaccinated countries, especially in HCWs with high risk for TB exposure.     

Tuberculosis notifications in Australia, 2004

The National Notifiable Disease Surveillance System received 1,076 tuberculosis (TB) notifications in 2004, of which 1,043 were new cases and 33 were relapses. The incidence of TB in Australia has remained at a stable rate since 1985 and was 5.4 cases per 100,000 population in 2004. The high-incidence groups remain people born overseas and Indigenous Australians at 21.7 and 8.1 cases per 100,000 population, respectively. By contrast, the incidence of TB in the non-Indigenous Australian-born population was 1.0 cases per 100,000 population. Comparison of the 2004 TB notification data against the performance indicators set by National Tuberculosis Advisory Committee highlights that enhanced TB control measures should be considered among these high-risk groups.     

传染病医院医务人员结核感染状况

目的了解传染病医院医务人员结核(TB)感染现况,探讨其感染TB的危险性及影响因素。方法对某传染病医院的全体医务工作者进行问卷调查和TB菌素纯蛋白衍化物（PPD）试验检测。结果该传染病医院全体职工TB感染发病率为48.18%。不同科室医务工作者的TB感染情况差异无统计学意义（P＞0.05）,不同工作年限、不同年龄、不同职称的医务工作者TB感染情况差异均有统计学意义（均P＜0.05）。文化程度、职称、目前居住情况、在结核感染门诊或病区的工作时间是TB感染的危险因素,其OR(95%CI)分别为1.70（1.03～2.80）、1.95（1.10～3.45）、1.84（1.03～3.28）、2.38（1.40～4.04）;个人防护是TB感染的保护因素［OR及OR95%CI为0.92（0.85～0.99）］。结论传染病医院的医务工作者是TB感染的高危人群,应加强自我防护意识,及早采取防护措施。