Tuberculosis outbreak in a long-term care facility

A systematic review on the causes of the transmission and control measures of outbreaks in long-term care facilities: Back to basics of infection control

BACKGROUND

The unique characteristics of long-term care facilities (LTCFs) including host factors and living conditions contribute to the spread of contagious pathogens. Control measures are essential to interrupt the transmission and to manage outbreaks effectively.

AIM

The aim of this systematic review was to verify the causes and problems contributing to transmission and to identify control measures during outbreaks in LTCFs.

METHODS

Four electronic databases were searched for articles published from 2007 to 2018. Articles written in English reporting outbreaks in LTCFs were included. The quality of the studies was assessed using the risk-of-bias assessment tool for nonrandomized studies.

FINDINGS

A total of 37 studies were included in the qualitative synthesis. The most commonly reported single pathogen was influenza virus, followed by group A streptococcus (GAS). Of the studies that identified the cause, about half of them noted outbreaks transmitted via person-to-person. Suboptimal infection control practice including inadequate decontamination and poor hand hygiene was the most frequently raised issue propagating transmission. Especially, lapses in specific care procedures were linked with outbreaks of GAS and hepatitis B and C viruses. About 60% of the included studies reported affected cases among staff, but only a few studies implemented work restriction during outbreaks.

CONCLUSIONS

This review indicates that the violation of basic infection control practice could be a major role in introducing and facilitating the spread of contagious diseases in LTCFs. It shows the need to promote compliance with basic practices of infection control to prevent outbreaks in LTCFs.

An outbreak of tuberculosis in a middle school in Henan, China: Epidemiology and risk factors

Background

In 2013, a tuberculosis (TB) outbreak occurred in a middle school in Henan province of China. An outbreak survey was carried out in the school.

Objectives

This study was undertaken to investigate the detection rate of TB cases and those with strong Mantoux positive (SMP), defined as tuberculin skin test (TST) indurations of 15mm or larger and/or blisters, necrosis or lymphangitis, and to identify their risk factors.

Methods

The TST, chest x-ray/radiography, and TB-suspicious symptoms interview were used to screen for TB cases. Their diagnosis was made by sputum smear microscopy, liquid culture, computed tomography (CT), and diagnostic therapy if necessary. We retrospectively analyzed the outbreak survey data of 4082 students and 278 staff in the school. Logistic regression models were used to identify the risk factors associated with SMP and TB disease.

Results

Approximately 3.55% of students and 16.55% of staff were SMP. SMP rate in students was significantly lower than that in staff (p<0.001). 55 TB cases in students and none in staff were identified in the school from February to November, 2013, with a detection rate of 1.35% for students. SMP and TB case detection rates were 20.29% and 41.77%, respectively, in the index class, both significantly higher than that in the other classes (3.26% and 0.55%, respectively; both p<0.001). In the index class, TB case detection rate over the study period in students with SMP was not significantly higher than that with TST indurations of <15mm (38.18% vs 21.43%, p = 0.24), but it was significantly higher in the other classes (7.81% vs 0.18%, p<0.001). Risk factors independently associated with SMP and TB cases shared the following with the index case: same dormitory-floor (adjusted odds ratio (AOR) 5.36, 95% CI 3.02–9.48, p<0.001 for SMP; AOR 2.67; 95% CI 1.03–6.96, p = 0.044 for TB cases), same classroom (AOR 4.01; 95% CI 1.95–8.26, p<0.001 for SMP; AOR 165.08; 95% CI 66.88–407.47, p<0.001 for TB cases), same teaching-floor in different classroom (AOR 5.41; 95% CI 3.02–9.71, p<0.001 for SMP; AOR 11.24; 95% CI 3.71–34.03, p<0.001 for TB cases) and same teaching-building on different floor (AOR 1.81; 95% CI 1.16–2.85, p = 0.009 for SMP; AOR 3.30; 95% CI 1.16–9.42, p = 0.025 for TB cases). The closer the contact was with the index case, the larger the AORs for SMP and TB cases were.

Conclusion

Same dormitory-floor, same classroom, same teaching-floor and same teaching-building with the index case were all risk factors for both TB infection and disease for students in the outbreak, and the closer the contact was with the index case, the higher the risk was observed. Attention should also be paid to students with TST indurations <15mm, as well as to those with that ≥15mm for the index class in dealing with the outbreak.

Using genotyping to delineate tuberculosis transmission in long-term care facilities: single facility 4-year experience

Background

Residents in long-term care facilities (LTCFs) are vulnerable to tuberculosis (TB) transmission; however, to delineate possible routes of TB transmission in LTCFs is difficult. This study aimed to address the use of regular genotyping surveillance to delineate TB transmission in LTCFs.

Methods

All of Mycobacterium tuberculosis isolates in the reported 620-bed LTCF between July 2011 and August 2015 were genotyped, and we retrospectively compared epidemiological data and genotyping results.

Results

A total of 42 subjects were diagnosed with culture-positive pulmonary TB infection during the 4-year period. Their median age was 76.5 years, and 64.3% (27/42) of them were male. Genotyping identified 5 clustered TB infections involving 76.2% (32/42) of all TB subjects. In a multivariate logistic regression model adjusted for age, sex, chronic obstructive pulmonary disease, and body mass index, subjects with clustered TB infection were less likely to be Activities of Daily Living (ADL)-dependence (adjOR 0.073, 95% CI 0.007–0.758) when compared with subjects having individual TB infections. Prolonged surveillance is essential given that the median interval to diagnose secondary subjects was 673 days. Finally, only 63.0% (17/27) of the 27 secondary TB subjects in this study had contact history with index subject in the same ward.

Conclusions

In conclusion, possible routes of TB transmission in a complex TB outbreak at LTCFs might be delineated by routine genotyping surveillance and regular health check-up.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-017-2526-2) contains supplementary material, which is available to authorized users.

Tuberculosis in Enclosed Populations

Transmission of tuberculosis (TB) is most effective in close contact indoor environments in various congregate settings including health care facilities, homeless shelters, correctional facilities, long-term care facilities, as well as community settings such as homes, schools, workplaces, and various modes of transportation. Outbreaks are fueled by numerous factors including the HIV epidemic, ease of global travel, unstable socio-economic and/or political situations, and lapses in response to potentially infectious patients. Organized approaches to TB control include an appropriate index of suspicion, identification and isolation of contagious patients in appropriate facilities, use of environmental controls, and personal protective equipment in accordance to national and international published guidelines. These all require tailoring to the various settings where TB is encountered using a determination of risk. Concerted efforts at the local, regional, national, and international levels at identifying patients with active disease, enforcing completion of treatment, and testing and fully treating patients with latent TB infection are paramount in reducing TB burden and continued transmission.

Tuberculosis in congregate settings: Policies and practices in various facilities in Mumbai, India

Congregate settings and correctional facilities have high risk of transmission of tuberculosis. They should have capacity to identify and diagnose cases early and initiate prompt treatment to prevent spread to inmates and staff. Appropriate interventions should ensure completion of treatment, documentation and reporting, and prevention of reactivation of successfully treated cases. This requires support from local health authorities. Although international policies and guidelines for infection control in congregate settings are available, there is very little information on how these are practiced in such settings. Our investigation highlights the policies and practices of various congregate facilities in the city of Mumbai.