Tuberculosis transmission from healthcare workers to patients and co-workers: a systematic literature review and meta-analysis

Risk of tuberculosis transmission by healthcare workers to children - a comprehensive review

Background

Children <15 years are at elevated risk of becoming infected with M. tuberculosis complex (Mtbc).

Objective

To assess the magnitude of Mtbc transmission by healthcare workers (HCW) to children.

Methods

Medline, Google Scholar and Cochrane library were searched to select primary studies in which HCW was the presumed index case and exposed infants and children aged below 15 years were screened for latent TB infection (LTBI).

Results

Of 4,702 abstracts, 19 original case reports covering one HCW each as presumed source case of Mtbc transmission to children, were identified. In sum, 11,511 children, of those 5,881 infants (51.1%), mostly in newborn nurseries, were considered contact persons and underwent tuberculin skin (TST) or Interferon gamma release assay (IGRA) testing. Test positivity was reported in 492/11,511 children (4.3%) coming from 14 studies. When test results considered falsely positive were excluded, the number of latently infected children decreased to 365/10,171 (3.6%). In all studies, the presumed duration of infectivity of the source case was, but the actual intensity and duration of exposure were not, decisive for the initiation of contact investigations. In only two of the studies, the contact time of the children towards the corresponding source case was estimated.

Conclusions

The results of our review suggest that the risk of Mtbc transmission from HCW to children in healthcare setting is considerably lower than reported in household settings. However, as the preselection of pediatric contacts appeared in most cases to be vague, the data found in the literature probably underestimates the actual risk.

Risk of tuberculosis transmission by children to healthcare workers - a comprehensive review

Background

Healthcare workers (HCWs) are at increased risk of becoming infected with M. tuberculosis complex (Mtbc).

Objective

To assess the magnitude of Mtbc transmission by children under the age of 15 years to HCW.

Methods

Medline, Google Scholar and Cochrane library were searched to select primary studies in which a child was the presumed index case and exposed HCW were screened for latent TB infection (LTBI).

Results

Of 4,702 abstracts, 15 original case reports covering 16 children with TB were identified. In sum, 1,395 HCW were contact persons and underwent testing. Ten of the studies reported TST conversion, amounting to 35 (2.9%) of the 1,228 HCW tested. In three of the TST-based and both of the studies that used IGRA testing, conversion was absent. 12 of the 15 studies (80%) reported exposure of HCW in neonatal intensive units (NICUs) to premature infants suffering from congenital pulmonary TB. One study including two infants addressed possible pulmonary Mtbc transmission in a general pediatric ward. Extrapulmonary transmission by aerosolized Mtbc was suggested in two patients, an infant with tuberculous peritonitis and a 12-year-old adolescent with pleurisy, and culture-confirmed only after the child had undergone video-assisted thoracoscopic surgery. Routine use of protective facemasks by HCW before exposure was not mentioned in any of the included studies.

Conclusions

The results suggest that the risk of Mtbc transmission from children to HCW is low. Particular attention should be paid to infection risk during respiratory manipulations in NICUs. The consistent wearing of facemasks may further reduce the risk of Mtbc transmission.

Healthcare workers' acceptance of and adherence to latent tuberculosis treatment

BACKGROUND

Healthcare workers (HCWs) with latent tuberculosis infection (LTBI) have a high risk of active tuberculosis and need systematic LTBI screening and treatment. However, acceptance and adherence rates of LTBI treatment are low.

AIMS

To examine the specific reasons for the loss at each LTBI treatment-cascade stage: acceptance, continuation and completion of LTBI treatment in HCWs.

METHODS

This retrospective descriptive study was conducted among 61 HCWs with an interferon-gamma release assay-confirmed LTBI diagnosis who were prescribed LTBI treatment at a tertiary hospital in the Republic of Korea. Data were analysed using Pearson's chi-square, Fisher's exact, independent t-test and Mann-Whitney U-test. A word cloud analysis was used to describe the perceived meaning of LTBI in HCWs.

RESULTS

HCWs who refused or discontinued LTBI treatment perceived LTBI as 'not a big deal', whereas HCWs who completed LTBI treatment had a high-risk perception of the LTBI prognosis, such as 'frightened about adverse prognosis'. Determinants of non-adherence to the recommended LTBI treatment included a busy work schedule, side effects of anti-tuberculosis agents and the inconvenience of regularly taking anti-tuberculosis agents.

CONCLUSIONS

To ensure LTBI treatment adherence in HCWs, effective interventions that are customized to each stage of the LTBI treatment should be developed, with due consideration of the stage-specific perceived facilitators and barriers in the LTBI treatment cascade.

Examining pulmonary TB patient management and healthcare workers exposures in two public tertiary care hospitals, Bangladesh

Implementation of tuberculosis (TB) infection prevention and control (IPC) guidelines in public tertiary care general hospitals remain challenging due to limited evidence of pulmonary TB (PTB) patients' duration of hospital stay and management. To fill this evidence gap, this study examined adult PTB patient management, healthcare workers' (HCWs) exposures and IPC practices in two public tertiary care hospitals in Bangladesh.Between December 2017 and September 2019, a multidisciplinary team conducted structured observations, a hospital record review, and in-depth interviews with hospital staff from four adult medicine wards.Over 20 months, we identified 1,200 presumptive TB patients through the hospital record review, of whom 263 were confirmed PTB patients who stayed in the hospital, a median of 4.7 days without TB treatment and possibly contaminated the inpatients wards. Over 141 observation hours, we found a median of 3.35 occupants present per 10 m2 of floor space and recorded a total of 17,085 coughs and 316 sneezes: a median of 3.9 coughs or sneezes per 10 m2 per hour per ward. Only 8.4% of coughs and 21% of sneezes were covered by cloths, paper, tissues, or by hand. The HCWs reportedly could not isolate the TB patients due to limited resources and space and could not provide them with a mask. Further, patients and HCWs did not wear any respirators.The study identified that most TB patients stayed in the hospitals untreated for some duration of time. These PTB patients frequently coughed and sneezed without any facial protection that potentially contaminated the ward environment and put everyone, including the HCWs, at risk of TB infection. Interventions that target TB patients screening on admission, isolation of presumptive TB patients, respiratory hygiene, and HCWs' use of personal protective equipment need to be enhanced and evaluated for acceptability, practicality and scale-up.

Tuberculosis Screening, Testing, and Treatment of US Health Care Personnel: ACOEM and NTCA Joint Task Force on Implementation of the 2019 MMWR Recommendations

: On May 17, 2019, the US Centers for Disease Control and Prevention and National Tuberculosis Controllers Association issued new Recommendations for Tuberculosis Screening, Testing, and Treatment of Health Care Personnel, United States, 2019, updating the health care personnel-related sections of the Guidelines for Preventing the Transmission of Mycobacterium tuberculosis in Health-Care Settings, 2005. This companion document offers the collective effort and experience of occupational health, infectious disease, and public health experts from major academic and public health institutions across the United States and expands on each section of the 2019 recommendations to provide clarifications, explanations, and considerations that go beyond the 2019 recommendations to answer questions that may arise and to offer strategies for implementation.

Determinants of Latent Tuberculosis Treatment Acceptance and Completion in Healthcare Personnel

BACKGROUND

US public health strategy for eliminating tuberculosis (TB) prioritizes treatment of latent TB infection (LTBI). Healthcare personnel (HCP) are less willing to accept treatment than other populations. Little is known about factors associated with HCP LTBI therapy acceptance and completion.

METHODS

We conducted a retrospective chart review to identify all employees with LTBI at time of hire at a large academic medical center during a 10-year period. Personal demographics, occupational factors, and clinic visit variables were correlated with LTBI treatment acceptance and completion rates using multivariate logistic regression.

RESULTS

Of 470 HCP with LTBI for whom treatment was recommended, 193 (41.1%) accepted treatment, while 137 (29.1%) completed treatment. Treatment adherence was better with 4 months of rifampin than 9 months of isoniazid (95% vs 68%, P < .005). Increased age of the healthcare worker was independently associated with lower rates of treatment acceptance (odds ratio [95% confidence interval]: 0.97 [0.94-0.99] per year), as was having an occupation of clinician (0.47 [0.26-0.85]) or researcher (0.34 [0.19-0.64]). Male gender was associated with higher treatment acceptance (1.90 [1.21-2.99]). Treatment completion was associated with being from a low- (9.49 [2.06-43.73]) or medium- (8.51 [3.93-18.44]) TB-burden country.

CONCLUSIONS

Geographic and occupational factors affect acceptance and completion of LTBI therapy. Short-course regimens may improve adherence. Physicians, researchers, and HCP from high-TB-burden countries have lower treatment rates than other HCP. Improving LTBI treatment in HCP will require attending to cultural and occupational differences.

The Effectiveness of Individual and Environmental Infection Control Measures in Reducing the Transmission of Mycobacterium tuberculosis: A Systematic Review

Background

Transmission of Mycobacterium tuberculosis in healthcare settings is a preventable driver of the global tuberculosis epidemic. We aimed to assess the evidence for infection control interventions, including cough etiquette, engineering and personal respiratory protection measures, to prevent transmission of M. tuberculosis in healthcare settings.

Methods

Three independent systematic reviews were performed using 6 databases and clinical trials websites. Randomized trials, cohort studies, before-after studies, and case-control studies were included. Searches were performed for controlled studies evaluating respiratory hygiene, engineering, and personal respiratory protection measures. Outcome measures included the incidence of tuberculosis infection and disease. Studies involving transmission to either humans or animals were included.

Results

Evaluation of respiratory hygiene and cough etiquette interventions identified 4 human studies, with 22 855 participants, and 1 guinea pig study. Studies in humans evaluated the effects of multiple concurrent interventions. Patient use of surgical masks reduced infection by 14.8%, and tuberculosis disease was reduced by between 0.5% and 28.9%. Engineering and environmental interventions were evaluated in 10 studies of humans, including 31 776 human participants, and 2 guinea pig studies. Mechanical ventilation was associated with between 2.9% and 14% less infection. Nine studies of personal respiratory protection were included, including 33 913 participants. Infection was reduced by between 0% and 14.8% in studies where particulate respirators were used. The quality of included studies was assessed as low.

Conclusions

Respiratory hygiene, engineering, and environmental infection controls and personal respiratory protection interventions were associated with reduced transmission of M. tuberculosis and reduced tuberculosis disease in healthcare settings.

Addressing the threat from within: Investigation of respiratory symptoms in a health care worker with untreated latent tuberculosis infection

Tuberculosis (TB) in the health care worker demands orchestrated efforts from health care institutions to promptly identify cases and address community risk. We describe a pediatric intensive care unit nurse with latent TB infection who developed hemoptysis and a lung infiltrate concerning for active TB. Her evaluation and contact investigation were facilitated by our institution's command center. Although TB was ultimately ruled out, this case tested our team-based care in response to a suspected high-consequence pathogen.

Effectiveness of interventions for reducing TB incidence in countries with low TB incidence: a systematic review of reviews

AIMS

What is the evidence base for the effectiveness of interventions to reduce tuberculosis (TB) incidence in countries which have low TB incidence?

METHODS

We conducted a systematic review of interventions for TB control and prevention relevant to low TB incidence settings (<10 cases per 100 000 population). Our analysis was stratified according to "direct" or "indirect" effects on TB incidence. Review quality was assessed using AMSTAR2 criteria. We summarised the strength of review level evidence for interventions as "sufficient", "tentative", "insufficient" or "no" using a framework based on the consistency of evidence within and between reviews.

RESULTS

We found sufficient review level evidence for direct effects on TB incidence/case prevention of vaccination and treatment of latent TB infection. We also found sufficient evidence of beneficial indirect effects attributable to drug susceptibility testing and adverse indirect effects (measured as sub-optimal treatment outcomes) in relation to use of standardised first-line drug regimens for isoniazid-resistant TB and intermittent dosing regimens. We found insufficient review level evidence for direct or indirect effects of interventions in other areas, including screening, adherence, multidrug-resistant TB, and healthcare-associated infection.

DISCUSSION

Our review has shown a need for stronger evidence to support expert opinion and country experience when formulating TB control policy.

Stigma against tuberculosis may hinder non-household contact investigation: a qualitative study in Thailand

Setting

A northern province in Thailand.

Objectives

To explore experiences and perspectives on tuberculosis (TB) contact investigations in non-household contacts.

Design

Focus group discussions and in-depth interviews with eight groups: three groups of former TB patients (teachers, students and hospital staff) and five groups of representatives from congregate settings such as schools and workplaces. Data were analysed using the modified grounded theory.

Result

Annual health check-ups at the workplace contributed to the early detection of active TB in teachers. Former TB patients were highly exposed to non-household contacts, but contact investigations were limited to household contacts only. Barriers and facilitators for non-household contact investigations are associated with five factors, including information, awareness and knowledge about TB; stigma; empathy; health system response and informing non-household contacts about TB exposure. Stigma may be the main barrier to investigations among non-household contacts because TB patients tend to withhold information about their diagnosis from colleagues. Lack of knowledge and misperceptions regarding TB transmission contributed to stigma. Empathy with other people encouraged TB patients to inform non-household contacts.

Conclusion

Non-household contact investigations are not performed despite the risk of TB transmission. To promote contact investigations in congregate settings, interventions to overcome TB stigma and improve public knowledge about TB transmission are required.

Risk of tuberculosis infection among health care workers and nursing students in Japan

It is important to evaluate the risk of tuberculosis (TB) infection among health care workers (HCWs) and nursing students in Japan to propose the optimal countermeasure against new TB infection for them. To estimate the annual incidence of TB infection in HCWs at a Japanese university hospital without TB wards and in nursing students at a Japanese university using interferon-gamma release assay (IGRA). Serial IGRAs were prospectively conducted on the HCWs between August 2010 and December 2015. For nursing students, two IGRA tests were conducted before commencement of clinical training and at employment as nurses between April 2007 and December 2015. A total of 328 HCWs and 298 nursing students were followed for 670.15 and 1212.80 person-years, respectively. Assuming IGRA-positive conversions were all attributable to true infection, the incidence of TB infection in HCWs and nursing students was 0.149/100 and 0.0825/100 person-years, respectively. At a Japanese university hospital without TB wards and a Japanese university, the annual incidence of TB infection among HCWs and nursing students estimated from serial IGRA results was low, but continued vigilance for the prevention of TB infection is essential.

Prevalence and risk factors of tuberculosis in developing countries through health care workers

In the last two decades, tuberculosis (TB) have threatened the public across the globe and continuing new TB cases and their transmission pooled with the global emergence of drug-resistant strains present an enduring occupational risk for health care workers (HCWs). Since last decade, government and funding agencies has given a significant amount of funds to tackle the problem of TB infection among medical staff or HCW in hospitals of developing countries, but the effects of these efforts have not yet been reported. Working environments are the major risk factors for TB infections among the HCW in hospital settings. Twenty-two high burden countries endorsed to the preponderance of worldwide tuberculosis cases in 2015. Urgent preventive strategies and mediations are needed to ensure the safety and sustained availability of these exquisite healthcare resources. This timeline review will provide the theoretical basis of high TB burden among the HCW which can be used for further improvement in strategies for the prevention of TB infections in hospital settings and provide a reliable basis for improving the personal health of HCW or medical staff.

BCG and New Preventive Tuberculosis Vaccines: Implications for Healthcare Workers

Healthcare workers (HCWs) are at high risk of Mycobacterium tuberculosis (Mtb) infection and tuberculosis disease, but also play a crucial role in implementing healthcare. Preexposure tuberculosis vaccination, including revaccination with BCG, might benefit Mtb-uninfected HCWs, but most HCWs in tuberculosis-endemic countries are already sensitized to mycobacteria. A new postexposure tuberculosis vaccine offers greatest potential for protection, in the setting of repeated occupational Mtb exposure. Novel strategies for induction of mycobacteria-specific resident memory T cells in the lung by aerosol administration, or induction of T cells with inherent propensity for residing in mucosal sites, such as CD1-restricted T cells and mucosa-associated innate T cells, should be explored. The need for improved protection of HCWs against tuberculosis disease is clear. However, health systems in tuberculosis-endemic countries would need significantly improved occupational health structures to implement a screening and vaccination strategy for HCWs.

Early diagnosis and effective treatment regimens are the keys to tackle antimicrobial resistance in tuberculosis (TB): A report from Euroscicon's international TB Summit 2016

To say that tuberculosis (TB) has regained a strong foothold in the global human health and wellbeing scenario would be an understatement. Ranking alongside HIV/AIDS as the top reason for mortality due to a single infectious disease, the impact of TB extends far into socio-economic context worldwide. As global efforts led by experts and political bodies converge to mitigate the predicted outcome of growing antimicrobial resistance, the academic community of students, practitioners and researchers have mobilised to develop integrated, inter-disciplinary programmes to bring the plans of the former to fruition. Enabling this crucial requirement for unimpeded dissemination of scientific discovery was the TB Summit 2016, held in London, United Kingdom. This report critically discusses the recent breakthroughs made in diagnostics and treatment while bringing to light the major hurdles in the control of the disease as discussed in the course of the 3-day international event. Conferences and symposia such as these are the breeding grounds for successful local and global collaborations and therefore must be supported to expand the understanding and outreach of basic science research.

Regular Sputum Check-Up for Early Diagnosis of Tuberculosis after Exposure in Healthcare Facilities

Background

The early diagnosis of patients with TB disease is critical after an outbreak of tuberculosis (TB) infection in healthcare facilities. In this study, we report a catastrophic TB outbreak in a psychiatric healthcare facility and analyze the role of regular sputum check-ups and other diagnostic tools to facilitate an early diagnosis.

Methods

Every exposed participant received regular sputum check-ups and chest X-rays (CXR) as part of the outbreak management protocol. We retrospectively analyzed data from the contact participants to identify risk factors for eventual TB development and investigated the diagnostic efficacy of regular sputum check-ups.

Results

Among 133 contact participants, 16 (12.0%) developed TB during the 4-year follow-up period. Low body-mass-index (BMI) (<21) (adjusted hazard ratio (aHR) 3.16, 95% confidence interval (CI) 1.11–8.98) and long duration of contact (>3 months) (aHR 8.70, 95% CI, 1.14–63.34) independently predicted the development of TB. Even though regular sputum check-ups required significant resources, they did facilitate the early identification of new TB cases among the contact participants. Regular sputum check-ups for high-risk patients based on BMI, contact duration and CXR findings may be a practical approach when compared with universal sputum follow-up, with a slightly decreased sensitivity but high positive likelihood ratio (88%, [95% CI, 62–98%] and 5.12, [95%CI, 3.30–7.95], respectively).

Conclusion

While regular sputum check-ups for all contact participants facilitated the early identification of cases after the outbreak of TB in the healthcare facility, regular sputum check-ups for high-risk patients might be an effective alternative in resource-limited settings.

Tuberculosis: Occupational risk among dental healthcare workers and risk for infection among dental patients. A meta-narrative review

OBJECTIVES

Tuberculosis transmission among healthcare workers (HCWs) and patients is due to the level of Mycobacterium tuberculosis (MT) circulation in the community and in the healthcare settings where HCWs are active. In contrast, most papers about dentistry report that dental HCWs (DHCWs) and patients are at relatively high risk, mainly based on tuberculosis case series that occurred in the 80's-90's. This meta-narrative review was designed to evaluate the tuberculosis risk in dentistry accounting for the historical-geographical contexts.

DATA

All available studies reporting data on MT infection (active/latent tuberculosis, tuberculin skin test) among patients and DHCWs.

SOURCES

PubMed, Scopus, GOOGLE Scholar.

KEYWORDS

MT/tuberculosis and dentistry/dentist/dental/dent*.

RESULTS

238 of the 351 titles were excluded because did not concern dental healthcare providing, 94 papers were excluded because they did not provide original data. Thirteen studies on occupational risk, nine on transmission to patients remained. Some, often non-confirmed, cases of MT infection among patients were reported in specific historical-geographical contexts where MT was endemic. The risk of active pulmonary tuberculosis transmission from infected DHCWs to patients is minimal today, provided that the basic infection control guidelines are applied. The development of active tuberculosis among DHCWs is occasional and is associable to MT circulation rather than dental healthcare providing.

CLINICAL SIGNIFICANCE

Tuberculosis transmission in dental healthcare settings was due to the lack of basic infection control measures, while the risk is acceptable (i.e., similar to the general population) nowadays. Therefore, tuberculosis transmission can be safely prevented wearing gloves and surgical mask and providing regular air changes in the operative and non-operative dental healthcare settings. Precautionary Principle-based measures are implementable when patients with active pulmonary tuberculosis are routinely treated.