Tuberculosis infection among close contacts of patients with pulmonary tuberculosis in China: a population-based, multicentered study.

OBJECTIVES: Limited information is currently available on the prevalence of and risk factors for tuberculosis infection (TBI) among close contacts of patients with pulmonary TB (PTB) in China. In this study, we estimated the burden of TBI among close contacts using QuantiFERON-TB Gold In-Tube assay (QFT) and identified factors associated with TB transmission among this high-risk population. METHODS: From January 1, 2018 to August 31, 2020, we identified laboratory-confirmed patients with PTB from a population-based, multicentered, cluster-randomized control trial for tuberculosis preventive treatment. Close contacts of these patients were identified, interviewed, and tested using the QFT assay. We estimated TBI prevalence and calculated ORs and 95% CIs for TBI risk factors. RESULTS: A total of 3138 index cases and 8117 close contacts were identified. Of these contacts, 36 had PTB (a prevalence of 443.51 cases/100 000 population). Among the remaining 7986 close contacts; 3124 (39.12%) reported a positive QFT result. QFT positivity was significantly associated with older age (adjusted OR, 1.77; [95% CI, 1.27-2.47], 2.20; [95% CI, 1.59-3.05], and 2.74; [95% CI, 1.96-3.82]) for age groups: 35-44, 45-54, and 55-64, respectively) when compared with a younger age group: 5-14; longer contact duration (adjusted OR, 1.44; 95% CI, 1.22-1.69); and sharing of a bedroom (adjusted OR, 1.39; 95% CI, 1.18-1.65). DISCUSSION: Our findings indicate a high TBI burden among the close contacts of PTB. The results also highlighted that contact tracing and investigation for TBI are necessary and beneficial, particularly for those who are older, have had a longer contact duration, and share a bedroom.

Effect of Smoking on Longitudinal Interferon-ϒ Release Assay Results among Close Contacts of People with Pulmonary Tuberculosis.

Diagnosis of M. tuberculosis (Mtb) infection in close contacts is critical for TB control. Smoking is a risk factor for Mtb infection and TB disease but its effect on longitudinal interferon-gamma release assay (IGRA) results remains unknown. We conducted a multi-site prospective study in Brazil between 2015-2019, among close contacts of adults with culture-confirmed pulmonary TB. IGRA was performed at baseline, month 6 if negative at baseline, and month 24-30 after enrollment. IGRA results were categorized as IGRA-positive (maintained from baseline to last visit), IGRA-conversion (from negative to positive at any time), IGRA-reversion (from positive to negative at any time), and IGRA-negative (maintained from baseline to last visit). Associations between IGRA results and smoking status at baseline (current/former vs never) in contacts were evaluated using propensity score-adjusted logistic regression models. Estimated propensity score was used as a covariate in models, which regressed the outcome (IGRA-positive, IGRA-conversion, IGRA-reversion) on smoking status. Of 430 close contacts, 89 (21%) were IGRA-positive, 30 (7%) were converters, 30 (7%) were reverters and 22 were indeterminate. Smoking frequency was 26 (29%) among IGRA-positive contacts, 7 (23%) in converters, and 3 (10%) in reverters. Smoking in contacts was associated with lower odds of IGRA-reversion (adjusted odds ratio = 0.16; 95% confidence interval = [0.03-0.70]). We did not detect associations between smoking and IGRA-positive or IGRA-conversion. Our findings highlight the importance of smoking on longitudinal IGRA results. This has implications for clinical care and clinical trials in which IGRA status is monitored or used as an outcome.

Association Studies of Serum Levels of TNF- α, IL-10, IFN-γ and CXCL 5 with Latent Tuberculosis Infection in Close Contacts.

Purpose: Early recognition and treatment of latent tuberculosis infection(LTBI) is key to tuberculosis(TB) prevention. However, the emergence of LTBI is influenced by a combination of factors, of which the role of individual immune cytokines remains controversial. The aim of this study is to explore the influencing factors of LTBI and their effects with cytokines on LTBI. Patients and Methods: Close contacts of tuberculosis in Urumqi City from 2021 to 2022 were selected for the study to conduct a field survey. It used logistic regression model to analyse the influencing factors of LTBI, principal component analysis to extract a composite indicators of cytokines, and structural equation modelling to explore the direct and indirect effects of cytokines and influencing factors on LTBI. Results: LTBI infection rate of 33.3% among 288 TB close contacts. A multifactorial Logistic model showed that factors influencing LTBI included education, daily contact hours, eating animal liver, and drinking coffee (P<0.05); After controlling for confounding factors and extracting composite indicators of cytokines using principal component analysis, CXCL5 and IFN-γ is a protective factor for LTBI(OR=0.572, P=0.047), IL-10 and TNF-α is a risk factor for LTBI(OR=2.119, P=0.010); Structural equation modelling shows drinking coffee, eating animal liver, daily contact hours, and IL-10 and TNF-α had direct effects on LTBI and educations had indirect effects on LTBI(P<0.05). Conclusion: IL-10 and TNF-α are involved in the immune response and are directly related to LTBI. By monitoring the cytokine levels of TB close contacts and paying attention to their dietary habits and exposure, we can detect and intervene in LTBI at an early stage and control their progression to TB.

Behavioral intentions of self-isolation and informing close contacts after developing mpox-related symptoms among young men who have sex with men in China.

The 2022 multi-country mpox outbreak raised public concern globally. Self-isolation and informing close contacts after developing mpox-related symptoms are critical measures in controlling the outbreak. This study investigated behavioral intentions of self-isolation and informing close contacts after developing mpox-related symptoms and associated factors among young men who have sex with men (YMSM) aged 18-29 years in China. The cross-sectional study was conducted among 2493 YMSM in six provincial regions in China from September 10th to 30th, 2022. Descriptive and logistic analyses were applied, using the intentions of self-isolation and informing close contacts after developing mpox-related symptoms as binary outcomes. The mean age of the participants was 24.6 (SD = 2.9) years. The prevalence of having intentions of self-isolation and informing close contacts after developing mpox-related symptoms was 88.6% (95% CI: 87.3%-89.9%) and 84.9% (95% CI: 83.5%-86.3%). Participants who were employed (adjusted odds ratio (AOR) = 1.474, 95% CI: 1.035-2.097; AOR = 1.371, 95% CI:1.002, 1.876), had higher mpox knowledge scores (AOR = 1.474, 95% CI: 1.035-2.097; AOR = 1.371, 95% CI: 1.002-1.876), and had higher perceived threats of mpox (AOR = 1.079, 95% CI: 1.030-1.130; AOR = 1.045, 95% CI: 1.002-1.090) were more likely to intend to self-isolate and inform close contacts. Participants who had MSM in-person gatherings in the past 6 months were more likely to intend to self-isolate (AOR = 1.392, 95% CI: 1.066-1.208). Participants with higher depression scores (AOR = 0.968, 95% CI: 0.948-0.989) and self-stigma (AOR = 0.975, 95% CI: 0.954-0.997) were less likely to intend to self-isolate and inform close contacts, respectively. Self-isolation and informing close contacts when developing disease-related symptoms are acceptable measures in response to mpox in China. Strengthening targeted risk communication and self-efficacy, raising disease knowledge, providing mental support, and reducing stigma toward the affected community are warranted.

The Xpert® MTB/RIF cycle threshold value predicts M. tuberculosis transmission to close contacts in a Brazilian prospective multicenter cohort.

BACKGROUND: The Xpert® MTB/RIF rapid molecular test provides a quantitative measure of Mycobacterium tuberculosis (Mtb) DNA in the form of cycle threshold (Ct) values. This information can be translated into mycobacterial load and used as a potential risk measure of bacterial spread for tuberculosis cases, which can impact infection control. However, the role of Ct values in assessing Mtb transmission to close contacts has not yet been demonstrated. METHODS: A prospective study was performed to investigate the association between Xpert® MTB/RIF Ct values and Mtb transmission to close contacts of patients with culture-confirmed pulmonary TB in a multi-center Brazilian cohort. We evaluated clinical and laboratory data, such as age, sex, race, smoking habits, drug use, alcohol use, chest radiograph, Xpert® MTB/RIF results among pulmonary tuberculosis cases, and QuantiFERON(QFT)-Plus results at baseline and after six months for close contacts who had a negative result at baseline. RESULTS: A total of 1,055 close contacts of 382 pulmonary tuberculosis cases were included in the study. The median Ct values from pulmonary tuberculosis cases of QFT-Plus positive (at baseline or six months) close contacts were lower compared with those who were QFT-Plus negative. An adjusted logistic regression demonstrated that reduced Ct values from the index cases were independently associated with QFT-Plus conversion from negative to positive (OR: 1.61, 95% CI: 1.12-2.32) after adjusting for clinical characteristics. CONCLUSION: Close contacts of pulmonary TB index cases exhibiting low Xpert MTB/RIF Ct values displayed higher rates of TB infection, reflecting Mtb transmission.

Association of Mycobacterium tuberculosis infection test results with risk factors for tuberculosis transmission.

Background: Close contacts infected with Mycobacterium tuberculosis are at high risk of tuberculosis (TB) disease and a priority for preventive treatment. Three tests measure infection: two interferon-gamma release assays (IGRAs) and the tuberculin skin test (TST). The objective of our study was to assess the association of positive test results in contacts with infectiousness of the presumed TB source case. Methods: Contacts in a cohort study at 10 United States sites received both IGRAs (QuantiFERON-TB Gold In-Tube (QFT-GIT) and T-SPOT.TB (T-SPOT)) and TST. We defined test conversion as negative for all tests at baseline and positive for at least one on retest. Risk ratios (RR) and 95% confidence intervals (CI) assessed association of positive test results with increased infectiousness of the TB case-defined as acid-fast bacilli (AFB) on sputum microscopy or cavities on chest radiographs- and contact demographics. Results: Adjusted for contacts' age, nativity, sex, and race, IGRAs (QFT-GIT RR = 6.1, 95% CI 1.7-22.2; T-SPOT RR = 9.4, 95% CI 1.1-79.1), but not TST (RR = 1.7, 95% CI 0.8-3.7), were more likely to convert among contacts exposed to persons with cavitary TB disease. Conclusions: Because IGRA conversions in contacts are associated with infectiousness of the TB case, their use may improve efficiency of health department contact investigations by focusing efforts on those likely to benefit from preventive treatment in the United States.

LTBI-negative close contacts of tuberculosis are more likely to develop the disease: enlightenment and lessons from a cluster outbreak.

Background: Tuberculosis (TB) prevention and control among groups living together, such as students, workers, older adults in nursing homes, and prisoners, present many challenges due to their particular age and environmental factors, which can make them more susceptible to TB clusters with significant societal impact. This study aimed to evaluate a TB cluster outbreak epidemic in a university and provide suggestions for improving TB control strategies for groups living together. Methods: Pulmonary TB screening and close-contact investigation were conducted using acid-fast staining, sputum culture, GeneXpert testing, tuberculin skin testing (TST), interferon-gamma release assay (IGRA), and chest computed tomography (CT). GraphPad Prism 9.5.1 was utilized for data analysis. Collected epidemic data were comprehensively analyzed by rate comparison. Results: The TB cluster outbreak epidemic was identified with an index case confirmed positive. The initial screening was conducted on potential close contacts of the index case, and the TST's positive rate (diameter ≥ 5 mm) and strong positive rate (diameter ≥ 15 mm) among these close contacts were 65.60% (21/32) and 34.40% (11/32), respectively. Moreover, the latent TB infection (LTBI) rate (diameter ≥ 10 mm) was 43.75% (14/32), and the IGRA's positive rate was 9.30% (3/32). Chest CT scans did not reveal any abnormalities. Surprisingly, 5 of the close contacts developed active TB in the second screening, accompanied by changes from negative to positive TST and/or IGRA results, after 3 months of follow-up. Accordingly, we expanded the screening scope to include another 28 general contacts. We found that the positive rate (78.00%, 25/32), strong positive rate (50.00%, 16/32), and LTBI rate (62.50%, 20/32) of the 32 close contacts were significantly higher than those of the additional general contacts (28.00%, 8/28; 14.3%, 4/28; 25.00%, 7/28), as indicated by p < 0.05. Conclusion: In the event of an epidemic TB outbreak, it is essential to rapidly identify the source of infection and initiate timely screening of close contacts. The initial screening should be focused on individuals without LTBI, who are at higher risk of developing TB. In purified protein derivative-negative individuals living in groups, additional vaccination or revaccination with Bacille Calmette-Guérin may help prevent cluster outbreaks of TB.

[Outbreak of monkeypox in the Canary Islands from may 15 to june 6, 2022]. / Estudio descriptivo del brote de viruela del simio en las Islas Canarias, mayo a octubre de 2022.

OBJECTIVE: Since May 2022, non-endemic countries reported the appearance of non-imported cases of monkeypox (Mpox). Spain was one of the most affected countries. The objective of the study was to describe the clinical-epidemiological characteristics of the first confirmed cases of Mpox in the Canary Islands and the main difficulties in contact tracing. METHODS: Retrospective observational descriptive study with confirmed cases of Mpox and their close contacts in the Autonomous Community of the Canary Islands. We conducted a descriptive analysis, using frequencies and percentages for qualitative variables, and median (interquartile range) for quantitative variables. RESULTS: One hundred and seventy-seven cases of Mpox were reported in the Canary Islands, with a median age of 39 years (32.8-48.3); 46.6% were HIV seropositive, and 6.8% were foreign. The most frequent clinical symptom was anogenital rash (68.8%), and at pustules stage (61.4%). One hundred and three declared risky sexual behaviors. Only fifty-three (30%) collaborated in the identification of close contacts. There were difficulties in: establishing communication with the cases, communicating the isolation measures, requesting tests, and due to delayed sample processing. CONCLUSIONS: Most common clinical symptom at diagnosis is anogenital rash in pustule stage. Most of the cases report risky sexual relations. The main barriers in contact tracing are the difficulty in contacting cases, the lack of identification data and the lack of experience of health professionals regarding Mpox.

OBJETIVO: Desde mayo de 2022, países no endémicos notificaron la aparición de casos no importados de viruela del simio (Mpox), siendo España uno de los más afectados. El objetivo del estudio fue describir las características clínico-epidemiológicas de los casos confirmados de Mpox en las Islas Canarias y las principales dificultades en el rastreo de contactos. METODOS: Se realizó un estudio retrospectivo observacional descriptivo con casos confirmados de Mpox y sus contactos estrechos en la Comunidad Autónoma de Canarias. Se realizó un análisis descriptivo, indicando frecuencias y porcentajes para variables cualitativas y mediana (rango intercuartílico) para cuantitativas. RESULTADOS: Se notificaron ciento setenta y siete casos de Mpox en las Islas Canarias, con una mediana de edad de 39 años (32,8-48,3), un 46,6% de seropositivos por VIH, y un 6,8% de extranjeros. La manifestación clínica más frecuente fue exantema anogenital (68,8 %), y en estadio de pústulas (61,4%). Ciento tres declararon conductas sexuales de riesgo. Solo cincuenta y tres (30%) colaboraron en la identificación de contactos estrechos. Se produjeron dificultades al establecer comunicación con los casos, al comunicar las medidas de aislamiento, en la solicitud de pruebas y, finalmente, debido al procesamiento de muestras con retraso. CONCLUSIONES: La manifestación clínica más frecuente al diagnóstico es el exantema anogenital en estadio de pústulas. La mayoría de los casos reportan relaciones sexuales de riesgo. Las principales barreras en el rastreo de contactos resultan la dificultad para contactar con los casos, la falta de datos de identificación y la inexperiencia de los profesionales sanitarios en relación con Mpox.

Syntheses and crystal structures of four 4-(4-meth-oxy-phen-yl)piperazin-1-ium salts: tri-fluoro-acetate, 2,3,4,5,6-penta-fluoro-benzoate, 4-iodo-benzoate, and a polymorph with 4-methyl-benzoate.

Syntheses and X-ray crystal structures of four 4-(4-meth-oxy-phen-yl)piperazin-1-ium (MeOPP) salts, with 2,2,2-tri-fluoro-acetate, C11H17N2O+·C2F3O2 - (I), 2,3,4,5,6-penta-fluoro-benzoate, C11H17N2O+·C7F5O2 -·H2O (II), 4-iodo-benzoate C11H17N2O+·C7H4IO2 -·H2O (III), and 4-methyl-benzoate, C11H17N2O+·C8H7O2 -·H2O (IV) anions are presented. The salts form directly from equimolar qu-anti-ties of N-(4-meth-oxy-phen-yl)piperazine and the corresponding organic acid in methanol and crystallize from 1:1 methanol/ethyl acetate. Salt I is anhydrous whereas II, III, and IV are all monohydrates. In all cases, the MeOPP cation conformation is determined by the torsion about the N-C bond between the piperazinium and 4-meth-oxy-benzene rings. Crystal packing in each structure is largely dictated by N-H⋯O and (in II, III, and IV) O-H⋯O hydrogen bonds, although each also features weak C-H⋯O-type hydrogen bonds. Salt II also has π-π-stacking inter-actions between cation and anion arene rings, and III exhibits I⋯I close contacts.

Estudio descriptivo del brote de viruela del simio en las Islas Canarias, mayo a octubre de 2022 / Outbreak of monkeypox in the Canary Islands from may 15 to june 6, 2022

Fundamentos: Desde mayo de 2022, países no endémicos notificaron la aparición de casos no importados de viruela del simio(Mpox), siendo España uno de los más afectados. El objetivo del estudio fue describir las características clínico-epidemiológicas delos casos confirmados de Mpox en las Islas Canarias y las principales dificultades en el rastreo de contactos.Métodos: Se realizó un estudio retrospectivo observacional descriptivo con casos confirmados de Mpox y sus contactos estrechos en la Comunidad Autónoma de Canarias. Se realizó un análisis descriptivo, indicando frecuencias y porcentajes para variablescualitativas y mediana (rango intercuartílico) para cuantitativas.Resultados: Se notificaron ciento setenta y siete casos de Mpox en las Islas Canarias, con una mediana de edad de 39 años(32,8-48,3), un 46,6% de seropositivos por VIH, y un 6,8% de extranjeros. La manifestación clínica más frecuente fue exantemaanogenital (68,8 %), y en estadio de pústulas (61,4%). Ciento tres declararon conductas sexuales de riesgo. Solo cincuenta y tres(30%) colaboraron en la identificación de contactos estrechos. Se produjeron dificultades al establecer comunicación con los casos,al comunicar las medidas de aislamiento, en la solicitud de pruebas y, finalmente, debido al procesamiento de muestras con retraso.Conclusiones: La manifestación clínica más frecuente al diagnóstico es el exantema anogenital en estadio de pústulas. Lamayoría de los casos reportan relaciones sexuales de riesgo. Las principales barreras en el rastreo de contactos resultan la dificultadpara contactar con los casos, la falta de datos de identificación y la inexperiencia de los profesionales sanitarios en relación con Mpox.(AU)

Background: Since May 2022, non-endemic countries reported the appearance of non-imported cases of monkeypox (Mpox).Spain was one of the most affected countries. The objective of the study was to describe the clinical-epidemiological characteristicsof the first confirmed cases of Mpox in the Canary Islands and the main difficulties in contact tracing.Methods: Retrospective observational descriptive study with confirmed cases of Mpox and their close contacts in the AutonomousCommunity of the Canary Islands. We conducted a descriptive analysis, using frequencies and percentages for qualitative variables, andmedian (interquartile range) for quantitative variables.Results: One hundred and seventy-seven cases of Mpox were reported in the Canary Islands, with a median age of 39 years(32.8-48.3); 46.6% were HIV seropositive, and 6.8% were foreign. The most frequent clinical symptom was anogenital rash (68.8%),and at pustules stage (61.4%). One hundred and three declared risky sexual behaviors. Only fifty-three (30%) collaborated in theidentification of close contacts. There were difficulties in: establishing communication with the cases, communicating the isolationmeasures, requesting tests, and due to delayed sample processing.Conclusions: Most common clinical symptom at diagnosis is anogenital rash in pustule stage. Most of the cases report riskysexual relations. The main barriers in contact tracing are the difficulty in contacting cases, the lack of identification data and the lackof experience of health professionals regarding Mpox.(AU)

Effect of Lianhua Qingwen capsules on the positive rate of COVID-19 close contacts: A retrospective analysis of a large-scale population-based cohort study.

OBJECTIVE: Coronavirus disease 2019 (COVID-19) is still spreading worldwide. COVID-19 close contact is a key point of this epidemic. However, no medication is now available for close contact. This study aims to evaluate the beneficial effect and safety of the Lianhua Qingwen capsule (LHQW) on COVID-19 close contacts via a large, retrospective cohort study. METHODS: A total of 25,002 close contacts from 199 quarantine sites in Changchun, Jilin, who underwent medical observation, were included. The information about these close contacts were collected for further epidemiological research. Moreover, subjects were divided into an exposure group (LHQW group, oral, 4 capsules/time, t.i.d.; 18,579 subjects) and a non-exposure group (control group; 6,423 subjects). Inverse probability of treatment weighting (IPTW) with propensity score was employed to evaluate the positive rate of the SARS-CoV-2 nucleic acid test in nasal and throat swabs confirmed by polymerase chain reaction (PCR). RESULTS: A total of 22,975 subjects were included in the analysis, 17,286 cases in the LHQW group and 5,689 cases in the control group. The positive rate of nucleic acid testing in the LHQW group was 5.12%, and that in the control group was 9.70% before the adjustment of IPTW of the propensity score; the difference between the two groups was -4.58% (95% CI -5.44- -3.77%, p <  0.001). After adjusting IPTW, the positive rate of nucleic acid testing in the LHQW group and the control group was 5.10% and 9.80%, respectively; the difference between the two groups was -4.70% (95% CI -5.18- -4.23, p < 0.001). The conclusions before and after the IPTW adjustment were consistent. No test drug-related adverse reactions were observed during the study period. CONCLUSION: LHQW has a beneficial effect and safety on the close contacts of SARS-CoV-2 who are under medical observation at the quarantine sites and can be used as an optional drug for those close contacts.

Test and Treat Model for Tuberculosis Preventive Treatment among Household Contacts of Pulmonary Tuberculosis Patients in Selected Districts of Maharashtra: A Mixed-Methods Study on Care Cascade, Timeliness, and Early Implementation Challenges.

Tuberculosis preventive treatment (TPT) is an important intervention in preventing infection and reducing TB incidence among household contacts (HHCs). A mixed-methods study was conducted to assess the "Test and Treat" model of TPT care cascade among HHCs aged ≥5 years of pulmonary tuberculosis (PTB) patients (bacteriologically/clinically confirmed) being provided TPT care under Project Axshya Plus implemented in Maharashtra (India). A quantitative phase cohort study based on record review and qualitative interviews to understand the challenges and solutions in the TPT care cascade were used. Of the total 4181 index patients, 14,172 HHCs were screened, of whom 36 (0.3%) HHCs were diagnosed with tuberculosis. Among 14,133 eligible HHCs, 10,777 (76.3%) underwent an IGRA test. Of them, 2468 (22.9%) tested positive for IGRA and were suggested for chest X-ray. Of the eligible 2353 HHCs, 2159 (91.7%) were started on TPT, of whom 1958 (90.6%) completed the treatment. The median time between treatment initiation of index PTB patient and (a) HHC screening was 31 days; (b) TPT initiation was 64 days. The challenges in and suggested solutions for improving the TPT care cascade linked to subthemes were tuberculosis infection testing, chest X-ray, human resources, awareness and engagement, accessibility to healthcare facilities, TPT drugs, follow-up, and assessment. A systematic monitoring and time-based evaluation of TPT cascade care delivery followed by prompt corrective actions/interventions could be a crucial strategy for its effective implementation and for the prevention of tuberculosis.

Qualitative Study on Psychological Experience of Close Contacts with COVID-19 during the Centralized Isolation Medical Observation Period / 中国医学伦理学

To analyze the psychological experience of close contacts with COVID-19 during the centralized isolation medical observation (centralized isolation for short) period, 17 close contacts of COVID-19 who received medical isolation observation at designated locations in a city of China were selected by purposive sampling using qualitative study methods, and the interviewees were interviewed by full-coverage structured telephone. By analyzing the obtained data and summarizing the themes, it was found that the psychological status of the COVID-19 close contacts during the centralized isolation period could be classified into three themes: obvious negative emotions, somatization of psychological problems, and demand for social support. During the epidemic, when close contacts were quarantined as high-risk groups, they often had complex and difficult psychological experiences. Relevant departments should actively carry out online guidance channels and offline knowledge dissemination, actively conduct psychological interventions for close contacts, assist them to develop life plans to enrich the life of the centralized isolation period. At the same time, relevant departments should do a good job in logistics and life support services, create a comfortable isolated living environment, and effectively relieve the negative emotions of close contacts of COVID-19 during centralized isolation through a variety of positive and effective measures to ensure physical and mental health.

Evaluation of screening methods for the students who had close contact with pulmonary tuberculosis patients in Shanghai / 上海预防医学

ObjectiveTo evaluate the current screening methods for the students who were in close contact with tuberculosis patients， that could accurately identify the preventive treatment subjects， and to improve the tuberculosis prevention and control in Shanghai schools. MethodsThe freshman/sophomore who were in close contact with active tuberculosis patients in the colleges in 2019 were recruited. All the subjects underwent both tuberculin skin test （TST） and QuantiFERON-TB gold in-tube （QFT） test at the enrollment. After signed the informed consent， all of the participants filled in a questionnaire and determined their baseline tuberculosis infection status. They were followed up for 2 years to monitor the conversion of infection status and the incidence of tuberculosis. ResultsFour of 9 （44.4%） positive participants had conversion to negative results， and 5 of 300 （1.7%） negative participants had conversion to positive during the 2-year follow-up， one of which was diagnosed with active tuberculosis. We assessed diagnostic agreement between QFT and TST at different cut-off values. The highest coincidence rate was 94.0% when choosing 15 mm as the cut-off value， with Kappa coefficient of 0.45 （95%CI： 0.32‒0.59）. ConclusionAlthough stricter than the national work requirements， the prevention and control of tuberculosis in Shanghai schools still need to be carried out meticulously. It's necessary to strengthen daily prevention and control measures， and improve the ability of management.

How to reduce the exposure risk of medical staff from SARS-CoV-2 by reducing environmental contamination: Experience from designated hospitals in China.

Background: Using daily monitoring of environmental surfaces and personal protective equipment (PPE), we found an increase in environmental contamination since August 18, 2021, in a designated hospital for COVID-19 patients in China, which may lead to an increased risk of exposure to medical staff. Methods: To investigate the cause of increased environmental contamination and effect of our intervention, we obtained environmental samples at pre-intervention (August 18-21, 2021) and post-intervention (August 22-28, 2021) from six infection isolation rooms with windows for ventilation and other auxiliary areas at 105 and 129 sites before routine daily cleaning, respectively. In addition, we obtained PPE samples from 98 medical staff exiting the patient rooms/contaminated areas at 482 sites. Between August 22 and 24, 2021, we took measures to reduce environmental contamination based on sampling and inspection results. Findings: At pre-intervention, the positivity rates for contamination of environmental surfaces and PPE samples were significantly higher for critical patients (37.21 and 27.86%, respectively) than severely ill patients (25.00 and 12.50%, respectively) and moderately ill patients (0.00 and 0.00%, respectively) (Pearson's Chi-square: χ2 = 15.560, p = 0.000; Fisher's exact test: χ2 = 9.358, p = 0.007). Therefore, we inferred that the source of contamination of environmental surfaces and PPE was mainly the room of critically ill patients, likely through the hands of medical staff to the potentially contaminated areas. A critically ill patient had emergency tracheal intubation and rescue on August 18, 2021, due to worsened patient condition. The ventilator tube used for first aid did not match the ventilator, and the ventilator tube fell off multiple times on August 18-21, 2021, which may explain the increased contamination of environmental surfaces and PPE from critically ill patients, as well as lead to indirect contamination of potentially contaminated areas. The contamination positivity rates of environmental surfaces and PPE were reduced by replacing the appropriate ventilator catheter, limiting the number of people entering the isolation room simultaneously, increasing the frequency of environmental disinfection, standardizing the undressing process, setting up undressing monitoring posts to supervise the undressing process, and preventing the spread of virus infections in the hospital during an epidemic. Conclusions: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was spread on object surfaces in isolation rooms mainly by touch, and the contamination of environmental surfaces and PPE was greater in rooms of patients with greater disease severity and higher surface touch frequency. Therefore, strict protective measures for medical staff, frequent environmental cleaning for isolation rooms, and compliance with mask wearing by patients when conditions permit should be advised to prevent SARS-CoV-2 spread in hospitals.

Infection rate and factors affecting close contacts of COVID-19 cases: A systematic review.

OBJECTIVE: Contact tracing plays an essential role in mitigating the impact of an epidemic. During the COVID-19 pandemic, studies of those who have been in close contact with confirmed cases offer critical insights to understand the epidemiological characteristics of SARS-CoV-2 better. This study conducts a meta-analysis of existing studies' infection rates and affecting factors. METHODS: We searched PubMed, Web of Science and CNKI from the inception to April 30 2022 to identify systematic reviews. Two reviewers independently extracted the data and assessed risk of bias. Meta-analyses were conducted to calculate pooled estimates by using Stata/SE 15.1 software. RESULTS: There were 47 studies in the meta-analysis. Among COVID-19 close contacts, older age (RR = 1.94, 95% CI: 1.70, 2.21), contacts in households (RR = 2.83, 95% CI: 2.20, 3.65), and people in close contact with symptomatic infections (RR = 3.62, 95% CI: 1.88, 6.96) were associated with higher infection rates. CONCLUSION: On average, each primary infection corresponded to 5.8 close contacts. Among COVID-19 close contacts, older age and contacts in households were associated with higher infection rates, and people in close contact with symptomatic infections had three times higher risk of infection compared to people in close contact with asymptomatic infections. In general, there are significantly more studies from China about close contacts, and the infection rate among close contacts was lower compared to other countries.

Prevalence of latent tuberculosis infection and incidence of active tuberculosis in school close contacts in Shanghai, China: Baseline and follow-up results of a prospective cohort study.

Background: The management of latent tuberculosis infection (LTBI) is a key action for the realization of the "End tuberculosis (TB) Strategy" worldwide, and it is important to identify priority populations. In this prospective cohort study, we evaluated the prevalence of LTBI and incidence of active TB among close contacts and explored the suitable TB control strategy in schools. Methods: We designed a cohort with 2 years of follow-up, recruiting freshman/sophomore TB patients' close contacts from three administrative districts in Shanghai. These were chosen based on different levels of TB incidence reported in 2019. Questionnaires were included and all participants received both tuberculin skin test (TST) and QuantiFERON-TB Gold (QFT) at baseline, then tracked the outcomes of them during the follow-up period. Results: The prevalence of LTBI was 4.8% by QFT. Univariate analysis showed that the risk of LTBI was higher in those contacting bacteriologically confirmed patients or did not have BCG scars, including smokers. The risk increased with poor lighting and ventilation conditions at contact sites. Multivariate analysis showed that those contacting with bacteriologically confirmed patients (OR=4.180; 95%CI, 1.164-15.011) or who did not have BCG scars (OR=5.054; 95%CI, 2.278-11.214) had a higher risk of being LTBI, as did the current smokers (OR=3.916; 95%CI, 1.508-10.168) and those who had stopped smoking (OR=7.491; 95%CI, 2.222-25.249). During the 2-year follow-up period, three clinically diagnosed cases of TB were recorded, the 2-year cumulative incidence was 0.4% (95%CI 0.1-1.2), the median duration for TB occurrence was 1 year, the incidence rate of active TB was 2.0 per 1000 person-years with a total of 1497.3 observation person-years. For those LTBI, no one initiated preventive treatment, in the QFT (+) cohort, 1 TB case was observed, 71 person-years with an incidence rate of 14.1 14.1 (95%CI 2.5-75.6) per 1000 person-years, in the TST (+++) cohort, 2 TB cases were observed 91.5 person-years with an incidence rate of 21.9 (95%CI 6.0-76.3) per 1000 person-years. Conclusions: The results suggest that school close contacts are one of the key populations for LTBI management. Measures should be taken to further reduce the prevalence of LTBI and the incidence of active TB among them.

Epidemiological and clinical characteristics of pertussis in children and their close contacts in households: A cross-sectional survey in Zhejiang Province, China.

Background: Despite the expanded immunization programs, the "re-emergence of pertussis" has become a global concern in recent years. At present, the prevalence of pertussis in China is seriously underestimated, and the role of close contact on the disease spreading in children remains unclear. Objectives: Our study aimed to investigate pertussis's epidemiological and clinical characteristics in children and their close contacts in households, as well as the antimicrobial resistance of Bordetella pertussis (B. pertussis) in Zhejiang Province, China. Methods: We have collected the retrospective and prospective data of children who were suspected of pertussis and their close contacts in households from January 1, 2018, to December 31, 2020, in the Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China. Nasopharyngeal swabs were collected and cultured for B. pertussis. Antibiotics susceptibility test was determined by using E-test methods. Clinical information was collected from the medical records systems. Results: A total of 350 index patients and their 946 family members (close contacts in households) from 350 families were recruited. B. pertussis strains were isolated from 130 (37.1%) index patients and 116 (12.3%) close contacts. 37 index patients had negative culture results for B. pertussis while their close contacts were positive. A higher positive rate was found in female adults than that in male adults (16.3% vs. 5.1%, P < 0.01). The positive rate in index patients from multi-child families was significantly higher than that from one-child families (51.7% vs. 37.7%, P < 0.05). 53.3% of the pertussis patients were under 6 months of age. 98 (75.4%) isolates had MICs ≥ 256 mg/L to erythromycin, azithromycin, and clindamycin, and 127 (97.7%) had MICs < 0.016 mg/L to piperacillin. Conclusion: Infants under 6 months of age are at high risk of pertussis, and close contacts in households are prone to cluster infection. Culture for B. pertussis both in children and their close contacts contributes to improving the diagnosis rate of pertussis in children. Isolates of B. pertussis in China are highly resistant to macrolides.

Family clustering of SARS-CoV-2 in Qazvin, Northwest of Iran.

Background: Human infection affected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been recognized as a global health concern. We report the epidemiological and clinical characteristics of patients with a familial cluster of SARS-CoV-2 from Qazvin province (located in the northwest of Iran). Methods: In this cross-sectional study, we enrolled 332 hospitalized patients that were confirmed SARS-CoV-2 diseases with laboratory-based (PT-PCR) test in Qazvin province, Iran. Having family infection transmission and subsequently, family clustering of SARS-COV-2 disease was assessed with the Generalized Estimating Equation model in patients. Results: Crude odds ratio estimates of creating family clustering of SARS-CoV-2 infection was 0.47 times [95% CI: 0.23, 0.98, p=0.045] less for female compared to the males; 2.26 [95% CI: 1.11, 4.58, p=0.024] and 2.69 [95% CI: 1.47, 4.93, p=0.001] for SARS-CoV-2 patients that had digestive and muscle pain in comparison with those did not this mentioned symptoms, respectively. 1.52 [95% CI: 1.05, 2.23, p=0.024] for patients with a longer hospitalization compared with patients that had shorter duration of hospitalization and adjusted odds ratio estimates were 2.13 [95% CI: 1.12, 4.03, p=0.020] for patients who receive public health services in comparison those did not receive public health services. Conclusion: Our findings confirm the person-to-person transmission of this novel coronavirus in family settings and hospitals, and the reports of infected travelers in other geographical regions. Major gaps in our knowledge about the potential factors in creating family clustering of SARS-CoV-2 infection, epidemiology, duration of human transmission and etc. need fulfillment by future studies.

COVID-19 contact tracing in the hospitals located in the North Denmark region: A retrospective review.

Background: The Department of Infection Control, at our University Hospital conducted contact tracing of COVID-19 positive patients and staff members at all hospitals in the North Denmark Region. Aim: To describe the contact tracing performed during the COVID-19 pandemic in the Region and its outcomes. Methods: Data from each contact tracing were collected prospectively during 14 May 2020-26 May 2021. Data included information about the index case (patient or hospital staff member), presentation (asymptomatic vs symptomatic), probable source of transmission (community-acquired or hospital-acquired), number of close contacts and if any of these were SARS-CoV-2 PCR-test positive. Findings: 362 contact tracing were performed. A total of 573 COVID-19 positive cases were identified among 171 (30%) patients and 402 (70%) staff members. 192 (34%) of all cases were tested due to symptoms of COVID-19, whereas two-third were tested for other reasons including outbreak and systematic screening tests. A total of 1575 close contacts were identified, including 225 (14%) patients and 1350 (86%) staff members. 100 (6%) close contacts, including 24 patients and 76 staff members, were infected with SARS-CoV-2, of which 33 (43%) staff members was positive at day 0 i.e. the same day as being identified as close contacts. Discussion: We found a three to one of close contacts to each index case, but only 6% became SARS-CoV-2 positive, with a surprisingly high number of those identified at day 0. Our data confirm that regular testing of patients and staff will identify asymptomatic carriers and thereby prevent new cases.