scholarly journals Performance of GeneXpert MTB/RIF for diagnosing tuberculosis among symptomatic household contacts of index patients in South Africa

2021 ◽  
Author(s):  
Kavindhran Velen ◽  
Laura J Podewils ◽  
N Sarita Shah ◽  
James J Lewis ◽  
Tiro Dinake ◽  
...  
Keyword(s):  
South Africa ◽  
Test Performance ◽  
Predictive Value ◽  
Poor Performance ◽  
Cross Sectional Study ◽  
Smear Microscopy ◽  
Cross Sectional ◽  
Household Contacts ◽  
Mgit Culture ◽  
Index Cases

Abstract Background We describe the performance of GeneXpert MTB/RIF (Xpert) for diagnosing tuberculosis (TB) among symptomatic household contacts (HHCs) of rifampicin-resistant and drug-sensitive index cases. Methods We conducted a cross-sectional study among HHCs of recently diagnosed (<2 weeks) smear-positive and Xpert-positive index cases in the Bojanala District, South Africa. HHCs were screened for TB symptoms; persons with ≥1 TB symptom provided one sputum for smear microscopy, Xpert and MGIT culture. Diagnostic test performance of Xpert was determined using MGIT as reference standard. Results From August 2013 to July 2015, 619 HHCs from 216 index cases were enrolled: 60.6% were female, median age was 22 years (inter-quartile range: 9, 40) and 126 (20.4%) self-reported/tested HIV-positive. 54.3% (336/619) of contacts had ≥1 TB symptom (cough, fever, night sweats, weight loss), of which 297/336 (88.4%) provided a sputum; 289 (97.3%) had complete testing and 271 were included in the analysis. In total, 42 (6.8%) of 619 HHCs had microbiologically-confirmed TB. MGIT identified 33 HHCs as positive for Mycobacterium tuberculosis (MTB); of these, 7 were positive on Xpert resulting in a sensitivity of 21.2% (95% confidence interval [CI]: 9.0, 38.9), specificity 98.3% (95% CI: 95.6, 99.5), positive predictive value (PPV) 63.6% (95% CI: 30.8, 89.1), negative predictive value (NPV) 90.0 (95% CI: 85.7, 93.4). Conclusions Among symptomatic HHCs investigated for TB, Xpert performed sub-optimally compared to MGIT culture. The poor performance of Xpert for diagnosing TB suggests that a more sensitive test, such a Xpert Ultra or culture, may be needed to improve yield of contact investigation, where feasible.

Blinded Rechecking of AFB smear Microscopy performance in Selected private health facilities in Tigray, Northern Ethiopia

2020 ◽  
Author(s):  
Letebrhan Weldemhret
Keyword(s):  
Predictive Value ◽  
Cost Effective ◽  
Cross Sectional Study ◽  
Health Facilities ◽  
Sputum Smear ◽  
Smear Microscopy ◽  
Northern Ethiopia ◽  
Major Error ◽  
Cross Sectional ◽  
Tigray Region

Abstract Background: Sputum smear microscopy remains the most cost-effective tool for tuberculosis diagnosis and treatment monitoring in resource constrained settings. Random blinded rechecking is a reliable tool to measure and improve smear microscopy. So, this study was intended to assess random blinded rechecking of AFB smear microscopy performance in selected private health facilities in Tigray region, Northern Ethiopia.Methods: A cross sectional study was conducted from April 1st 2017 to May 30, 2017. The data was collected using standard data collection form. Statistical analysis was done using SPSS version 25 and the reading agreement was done using kappa statistics.Results: Of the total 269 blinded rechecked smears, 4.8% was found discrepant findings. The major and minor errors were reported by 2.6% (7/269) and 2.2% (6/269) respectively. Likewise, the major error was reported by 50% (5/10) of health facilities with microscopic center. Overall, the sensitivity, specificity, positive predictive value, and negative predictive value of the blinded rechecking smears were 87.5%, 98%, 89.7% and 97.8%, respectively with substantial reading agreement, kappa value= 0.80.Conclusions: The overall performance of blinded rechecking was satisfactory with good smear reading agreement. But, the major error reported indicated unacceptable performance. To minimize the discrepancy, private health facilities with tuberculosis smear microscopic center should adhere to national tuberculosis guidelines.

scholarly journals Isoniazid Preventative Therapy uptake for child household contacts of tuberculosis index cases, Kisumu County, Kenya, 2014-2015

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Barbara Burmen ◽  
Kennedy Mutai ◽  
Timothy Malika
Keyword(s):  
Cross Sectional Study ◽  
Diagnostic Tools ◽  
Case Detection ◽  
Preventative Therapy ◽  
Cross Sectional ◽  
Worker Training ◽  
Household Contacts ◽  
Isoniazid Preventative Therapy ◽  
Pediatric Tb ◽  
Index Cases

Isoniazid Preventative Therapy (IPT) is recommended for children aged less than 5 years that have been in contact with an open case of TB, and screen negative for TB, to prevent the risk of TB progression. We examined IPT uptake among child household contacts of TB index cases, within a TB case detection study, in a high TB burden region. A cross-sectional study involving all IPT-eligible children drawn from a TB case detection study was done in Kisumu County, Kenya between 2014 and 2015. By linking a subset of the study database to the TB program IPT register, we described Child contacts as initiated on IPT and TB index cases as having child contacts initiated on IPT based on whether their names or their child contacts names respectively, were found in the IPT register. Logistic regression analysis was used to describe index and contact characteristics associated with IPT initiation. Of 555 TB index cases recruited into the study, 243 (44%) had a total of 337 IPT-eligible child contacts. Forty-seven (19%) index cases that had child contacts initiated on IPT; they were more likely to have been diagnosed with smear positive TB compared to those who were diagnosed with smear negative TB (OR 5.1, 95% CI 1.1-23.2; P=0.03) and to reside in rural Kisumu compared to those in urban Kisumu (OR 3.3, 95% CI 1.6-6.8; P<0.01). The 51 (15%) child contacts that were initiated on IPT were more likely to be were first degree relatives of the index case compared to those who were not (OR 2.6, 95% CI 1.2-5.5; P=0.02) and to reside in rural Kisumu compared to those in urban Kisumu (OR 2.6, 95% CI 1.2-5.1; P<0.01). IPT initiation, which is influenced by index and contact characteristics, is suboptimal. The TB program should provide health worker training, avail appropriate pediatric TB diagnostic tools, job aids and monitoring tools, and ensure continuous supply of medication, and to facilitate IPT implementation. Additionally, targeted health education interventions should be formulated to reach those who are unlikely to accept IPT.

scholarly journals Psychological capital, job demands and organisational commitment of employees in a call centre in Durban, South Africa

2014 ◽  
Vol 14 (1) ◽  
Author(s):  
Kreshona Pillay ◽  
Johanna H. Buitendach ◽  
Herbert Kanengoni
Keyword(s):  
South Africa ◽  
Significant Relationship ◽  
Predictive Value ◽  
Psychological Capital ◽  
Job Demands ◽  
Cross Sectional Study ◽  
Medium Effect ◽  
Call Centre ◽  
Organisational Commitment ◽  
Cross Sectional

Orientation: The South African call centre industry is growing as call centres are increasingly used as a means of service delivery to customers. Positive psychologists posit that psychological capital could lead to positive outcomes such as organisational commitment of call centre staff.Research purpose: This study investigated the relationship between psychological capital, job demands and organisational commitment and intended to determine whether psychological capital and job demands predict call centre employees’ organisational commitment.Motivation for the study: The study aimed to explore potential links between psychological capital, job demands and organisational commitment of call centre employees. It is premised on previous research that call centre job demands may be related to commitment to the organisation.Research approach, design and method: This cross-sectional study sampled 117 call centre employees from Durban, South Africa, and used a biographical questionnaire, psychological capital questionnaire, the job-demands-resources scale and the organisational commitment questionnaire to collect data.Main findings: Findings indicated a statistically significant relationship between psychological capital and work overload, as well as a practically and statistically significant relationship (medium effect) between psychological capital and continuance organisational commitment. The results showed that psychological capital has predictive value for continuance organisational commitment.Practical/managerial implications: Psychological capital has predictive value for continuance organisational commitment. Organisations can develop initiatives to enhance positive psychological states and address this relationship.Contribution: The findings could be beneficial to management and employees in considering ways to boost psychological capital in order to improve organisational commitment.

scholarly journals Performance of LED Fluorescence Microscopy for the Diagnosis of Pulmonary Tuberculosis in HIV Positive Individuals in Addis Ababa, Ethiopia

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Konjit Getachew ◽  
Tamrat Abebe ◽  
Abebaw Kebede ◽  
Adane Mihret ◽  
Getachew Melkamu
Keyword(s):  
Pulmonary Tuberculosis ◽  
Predictive Value ◽  
Addis Ababa ◽  
Sputum Sample ◽  
Cross Sectional Study ◽  
Hiv Positive ◽  
Smear Microscopy ◽  
Lower Sensitivity ◽  
Cross Sectional ◽  
Sensitivity Specificity

Background. Despite its lower sensitivity, smear microscopy remains the main diagnostic method for pulmonary tuberculosis (PTB) in resource-limited countries as TB culturing methods like LJ (Lowenstein-Jensen) are expensive to use as a routine base. This study aimed to evaluate the performance of LED-FM for the diagnosis of PTB in HIV positive individuals.Methods. Cross-sectional study was conducted in Zewditu Memorial Hospital and Teklehaimanot Health Center HIV/ART clinics in Addis Ababa, Ethiopia. Each sample was stained with ZN and Auramine O staining and examined with bright-field microscope and LED-FM microscope, respectively. LJ culture was used as a reference.Results. Out of 178 study participants, twenty-four (13.5%) patients were confirmed as positive for MTB with LJ culture. The yield of ZN microscopy and LED-FM in direct and concentrated sample was 3.9%, 8.4%, 6.2%, and 8.4%, respectively. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of direct ZN microscopy were 29.2%, 100%, 100%, and 90.1%, respectively, and of LED-FM microscopy in direct sputum sample were 62.5%, 100%, 100%, and 94.5%, respectively.Conclusion. LED-FM has better sensitivity for the diagnosis of PTB in HIV positive individuals as compared to conventional ZN microscopy. LED-FM can be used as an alternative to conventional ZN microscopy.

scholarly journals On the SARS-CoV-2 “Variolation Hypothesis”: No Association Between Viral Load of Index Cases and COVID-19 Severity of Secondary Cases

2021 ◽  
Vol 12 ◽  
Author(s):  
Mattia Trunfio ◽  
Bianca Maria Longo ◽  
Francesca Alladio ◽  
Francesco Venuti ◽  
Francesco Cerutti ◽  
...  
Keyword(s):  
Viral Load ◽  
Cross Sectional Study ◽  
Pharyngeal Swab ◽  
Cross Sectional ◽  
Household Contacts ◽  
Negative Findings ◽  
Novel Coronavirus ◽  
Public Health Strategies ◽  
Index Cases ◽  
Exact Quantification

Background: Emerging evidence supports the “variolation hypothesis” in severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), but the derivative idea that the viral load of index cases may predict disease severity in secondary cases could be unsubstantiated. We assessed whether the prevalence of symptomatic infections, hospitalization, and deaths in household contacts of 2019 novel coronavirus disease (COVID-19) cases differed according to the SARS-CoV-2 PCR cycle threshold (Ct) from nasal-pharyngeal swab at diagnosis of linked index cases.Methods: Cross-sectional study on household contacts of COVID-19 cases randomly sampled from all the infections diagnosed in March at our Microbiology Laboratory (Amedeo di Savoia, Turin). Data were retrospectively collected by phone interviews and from the Piedmont regional platform for COVID-19 emergency. Index cases were classified as high (HVl) and low viral load (LVl) according to two exploratory cut-offs of RdRp gene Ct value. Secondary cases were defined as swab confirmed or symptom based likely when not tested but presenting compatible clinical picture.Results: One hundred thirty-two index cases of whom 87.9% symptomatic and 289 household contacts were included. The latter were male and Caucasian in 44.3 and 95.8% of cases, with a median age of 34 years (19–57). Seventy-four were swab confirmed and other 28 were symptom based likely secondary cases. Considering both, the contacts of HVl and LVl did not differ in the prevalence of symptomatic infections nor COVID-19-related hospitalization and death. No difference in median Ct of index cases between symptomatic and asymptomatic, hospitalized and not hospitalized, or deceased and survived secondary cases was found. Negative findings were confirmed after adjusting for differences in time between COVID-19 onset and swab collection of index cases (median 5 days) and after removing pediatric secondary cases.Conclusions: The amount of SARS-CoV-2 of the source at diagnosis does not predict clinical outcomes of linked secondary cases. Considering the impelling release of assays for SARS-CoV-2 RNA exact quantification, these negative findings should inform clinical and public health strategies on how to interpret and use the data.

scholarly journals Isoniazid preventative therapy uptake for child household contacts of TB index cases, Kisumu County, Kenya, 2014-2015

2018 ◽  
Vol 9 (1) ◽  
Author(s):  
Barbara Burmen ◽  
Kennedy Mutai ◽  
Timothy Malika
Keyword(s):  
Cross Sectional Study ◽  
Diagnostic Tools ◽  
Case Detection ◽  
Preventative Therapy ◽  
Cross Sectional ◽  
Worker Training ◽  
Household Contacts ◽  
Isoniazid Preventative Therapy ◽  
Pediatric Tb ◽  
Index Cases

Background Isoniazid Preventative Therapy (IPT) is recommended for children aged less than 5 years that have been in contact with an open case of TB and screen negative for TB to prevent the risk of TB progression. We examined IPT uptake among child household contacts of TB index cases within a TB case detection study in a high TB burden region. Methods A cross-sectional study involving all IPT eligible children drawn from a TB case detection study was done in Kisumu County, Kenya between 2014 and 2015. By linking a subset study database to the TB program IPT register, we described Child contacts as ‘initiated on IPT’ and TB index cases as ‘having child contacts initiated on IPT’ based on whether their names or their child contacts names respectively, were found in the IPT register. Logistic regression analysis was used to describe index and contact characteristics associated with IPT initiation Results Of 555 TB index cases into the study, 243 (44%) had a total of 337 IPT-eligible child household contacts. Forty-seven (19%) index cases that had child contacts initiated on IPT; they were more likely to have been diagnosed with smear positive TB compared to those who were diagnosed with smear negative TB (OR 5.1, 95% CI 1.1-23.2; p=0.03) and to reside in rural Kisumu compared to those in urban Kisumu (OR 3.3, 05% CI 1.6-6.8; p<0.01). The 51 (15%) child contacts that were initiated on IPT were more likely to be were first degree relatives of the index case compared to those who were not (OR 2.6, 95% CI 1.2-5.5; p=0.02) and to reside in rural Kisumu compared to those in urban Kisumu (OR 2.6, 95% CI 1.2-5.1; p<0.01). Conclusion IPT initiation, which is influenced by index and contact characteristics, is suboptimal. The TB program should provide health worker training, avail appropriate pediatric TB diagnostic tools and continuous supply of medication, and job aids and monitoring tools to facilitate IPT implementation. Additionally, targeted health education interventions should be formulated to reach those who are unlikely to accept IPT.

scholarly journals Evaluation of Truenat MTB/RIF Test in Comparison with Microscopy and Culture for Diagnosis of Extrapulmonary Tuberculosis in a Tertiary Care Centre

2021 ◽  
Author(s):  
Reena Anie Jose ◽  
Krishna Gopal ◽  
Abel K Samuel Johnson ◽  
Jennie Ann Johnson Samuel ◽  
Sherin Susan Abraham ◽  
...  
Keyword(s):  
Predictive Value ◽  
Point Of Care ◽  
Extrapulmonary Tuberculosis ◽  
Tertiary Care ◽  
Cost Effective ◽  
Cross Sectional Study ◽  
Smear Microscopy ◽  
Tertiary Care Centre ◽  
Cross Sectional ◽  
Fitting In

Introduction: Worldwide, Extrapulmonary Tuberculosis (EPTB) accounts for 15-20% of all cases of TB. The diagnosis of EPTB is a big challenge, as the number of Mycobacterium tuberculosis(MTB) bacilli in the tissues and other organs is often very low. Truenat MTB/RIF (rifampicin) is a novel method, which is battery operated, point-of-care and chip-based Real Time Polymerase Chain Reaction (RT-PCR) micro device. Aim: To evaluate Truenat as a screening test in the diagnosis of EPTB in comparison with microscopy and culture. Materials and Methods: A prospective cross-sectional study was carried out over a year in which samples from suspected cases of EPTB fitting in the inclusion criteria were subjected to Ziehl-Neelsen (ZN) staining for smear microscopy, culture on Lowenstein Jensen (LJ) medium and PCR for MTB by Truenat. Comparisons were made between the tests and the data was presented using summary statistics with 95% Confidence Interval (CI). Results: A total of 248 samples were received from suspected cases of EPTB. Out of the different samples tested, 9 (3.6%) were positive with Truenat MTB. The predominant type of EPTB observed in the study was lymph node Tuberculosis (TB) (66.6%) followed by intestinal, pleural and skeletal TB. Out of the 106 samples tested for culture, four were culture positive for MTB and out of 178 samples tested for microscopy, three were positive for acid fast bacilli. Sensitivity, specificity, Negative Predictive Value (NPV), Positive Predictive Value (PPV), observed agreement of Truenat with culture and microscopy were 100%, 95.1%, 100%, 44.4%, 95.3% and 100%, 96.6%, 100%, 33.3%, 96.6%, respectively. Conclusion: Truenat MTB test is a cost-effective rapid molecular test with good sensitivity and specificity for the diagnosis of EPTB in low resource settings.

scholarly journals Willingness to Take Multidrug-resistant Tuberculosis (MDR-TB) Preventive Therapy Among Adult and Adolescent Household Contacts of MDR-TB Index Cases: An International Multisite Cross-sectional Study

2019 ◽  
Vol 70 (3) ◽  
pp. 436-445
Author(s):  
Nishi Suryavanshi ◽  
Matthew Murrill ◽  
Amita Gupta ◽  
Michael Hughes ◽  
Anneke Hesseling ◽  
...  
Keyword(s):  
Multidrug Resistant ◽  
Cross Sectional Study ◽  
Preventive Therapy ◽  
Sectional Study ◽  
Cross Sectional ◽  
Household Contacts ◽  
Resistant Tuberculosis ◽  
Multidrug Resistant Tuberculosis ◽  
Mdr Tb ◽  
Index Cases

Abstract Background Household contacts (HHCs) of individuals with multidrug-resistant tuberculosis (MDR-TB) are at high risk of infection and subsequent disease. There is limited evidence on the willingness of MDR-TB HHCs to take MDR-TB preventive therapy (MDR TPT) to decrease their risk of TB disease. Methods In this cross-sectional study of HHCs of MDR-TB and rifampicin-resistant tuberculosis (RR-TB) index cases from 16 clinical research sites in 8 countries, enrollees were interviewed to assess willingness to take a hypothetical, newly developed MDR TPT if offered. To identify factors associated with willingness to take MDR TPT, a marginal logistic model was fitted using generalized estimating equations to account for household-level clustering. Results From 278 MDR-TB/RR-TB index case households, 743 HHCs were enrolled; the median age of HHCs was 33 (interquartile range, 22–49) years, and 62% were women. HHC willingness to take hypothetical MDR TPT was high (79%) and remained high even with the potential for mild side effects (70%). Increased willingness was significantly associated with current employment or schooling (adjusted odds ratio [aOR], 1.83 [95% confidence interval {CI}, 1.07–3.13]), appropriate TB-related knowledge (aOR, 2.22 [95% CI, 1.23–3.99]), confidence in taking MDR TPT (aOR, 7.16 [95% CI, 3.33–15.42]), and being comfortable telling others about taking MDR TPT (aOR, 2.29 [95% CI, 1.29–4.06]). Conclusions The high percentage of HHCs of MDR-TB/RR-TB index cases willing to take hypothetical MDR TPT provides important evidence for the potential uptake of effective MDR TPT when implemented. Identified HHC-level variables associated with willingness may inform education and counseling efforts to increase HHC confidence in and uptake of MDR TPT.

scholarly journals Increased Transmissibility of the SARS-CoV-2 Alpha Variant in a Japanese Population

2021 ◽  
Vol 18 (15) ◽  
pp. 7752
Author(s):  
Hideo Tanaka ◽  
Atsushi Hirayama ◽  
Hitomi Nagai ◽  
Chika Shirai ◽  
Yuki Takahashi ◽  
...  
Keyword(s):  
Japanese Population ◽  
Error Variance ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
Fourth Group ◽  
Household Contacts ◽  
The Third ◽  
Before And After ◽  
Alpha Variant ◽  
Index Cases

To assess the relative transmissibility of the SARS-CoV-2 Alpha variant compared to the pre-existing SARS-CoV-2 in Japan, we performed a cross-sectional study to determine the secondary attack rate of COVID-19 in household contacts before and after the Alpha variant became dominant in Osaka. We accessed 290 household contacts whose index cases were diagnosed between 1 and 20 December 2020 (the third epidemic group), at a time when Osaka was free of the Alpha variant. We also accessed 398 household contacts whose index cases were diagnosed between 20 April and 3 May 2021 (the fourth epidemic group), by which time the Alpha variant had become dominant. We identified 124 household contacts whose index case was determined positive for the Alpha variant (Alpha group) in this fourth group. The secondary attack rates in the fourth group (34.7%) and the Alpha group (38.7%) were significantly higher than that in the third group (19.3%, p < 0.001). Multivariable Poisson regression analysis with a robust error variance showed a significant excess risk in the fourth group (1.90, 95% CI = 1.47–2.48) and the Alpha group (2.34, 95% CI = 1.71–3.21). This finding indicates that the SARS-CoV-2 Alpha variant has an approximately 1.9–2.3-fold higher transmissibility than the pre-existing virus in the Japanese population.

scholarly journals Excess Risk of Tuberculosis Infection Among Extra-household Contacts of Tuberculosis Cases in an African City

2020 ◽  
Author(s):  
Robert Kakaire ◽  
Noah Kiwanuka ◽  
Sarah Zalwango ◽  
Juliet N Sekandi ◽  
Trang Ho Thu Quach ◽  
...  
Keyword(s):  
Cross Sectional Study ◽  
Excess Risk ◽  
Tuberculosis Infection ◽  
African City ◽  
Cross Sectional ◽  
Control Networks ◽  
Household Contacts ◽  
Prevalence Difference ◽  
And Control ◽  
Index Cases

Abstract Background Although households of tuberculosis (TB) cases represent a setting for intense transmission of Mycobacterium tuberculosis, household exposure accounts for &lt;20% of transmission within a community. The aim of this study was to estimate excess risk of M. tuberculosis infection among household and extra-household contacts of index cases. Methods We performed a cross-sectional study in Kampala, Uganda, to delineate social networks of TB cases and matched controls without TB. We estimated the age-stratified prevalence difference of TB infection between case and control networks, partitioned as household and extra-household contacts. Results We enrolled 123 index cases, 124 index controls, and 2415 first-degree network contacts. The prevalence of infection was highest among household contacts of cases (61.5%), lowest among household contacts of controls (25.2%), and intermediary among extra-household TB contacts (44.9%) and extra-household control contacts (41.2%). The age-adjusted prevalence difference between extra-household contacts of cases and their controls was 5.4%. The prevalence of infection was similar among the majority of extra-household case contacts and corresponding controls (47%). Conclusions Most first-degree social network members of TB cases do not have adequate contact with the index case to experience additional risk for infection, but appear instead to acquire infection through unrecognized exposures with infectious cases in the community.

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