scholarly journals Identification of subclinical tuberculosis in household contacts using exposure scores and contact investigations

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Gry Klouman Bekken ◽  
Christian Ritz ◽  
Sumithra Selvam ◽  
Nelson Jesuraj ◽  
Anneke C. Hesseling ◽  
...  
Author(s):  

AbstractBetween January 24 and March 10, of a total of 2,370 individuals who had contacted the first 30 cases of COVID-19, 13 were found to have COVID-19, resulting secondary attack rate of 0.55% (95% CI 0.31 – 0.96). Of 119 household contacts, 9 had infections resulting secondary attack rate of 7.56 (95% CI 3.73 – 14.26).


2020 ◽  
Author(s):  
Camila Massae Sato ◽  
Omar Ariel Espinosa Domínguez ◽  
Gutembergue Santos de Sousa ◽  
Fabiane Verônica da Silva ◽  
Roberta Olmo Pinheiro ◽  
...  

BACKGROUND Leprosy contacts are sensitive indicator of the magnitude of severity, and a high risk for infection and disease, especially if the individuals are exposed to the bacillus with multibacillary cases, which reinforces the need for chemoprophylactic measures, such as the use single-dose rifampicin (SDR) combined with BCG vaccine. OBJECTIVE Our study will analyze the serological response of anti-NDO-LID, HO-1/HMOX and serum IFN-γ concentration as a prophylactic measure after the use of single-dose rifampicin (SDR) combined with the Bacillus Calmette-Guérin vaccine (BCG) among multibacillary leprosy household contacts. METHODS Intervention study based on a prospective cohort of household contacts of new cases of multibacillary leprosy diagnosed and registered in the Information System on Diseases of Compulsory Declaration (SINAN – Sistema de Informação de Agravos de Notificação) and residents in the municipalities of Cuiabá and Cáceres, Mato Grosso, in the years 2019 and 2020. Contacts with no signs and symptoms compatible with the disease of the intervention group will receive single-dose rifampicin (SDR) combined with BCG vaccine and will be compared to the control group. The follow-up of the cohort will last 12 months. The analyses of the anti-NDO-LID, HO-1/HMOX and serum concentration of IFN-γ tests as immunological markers before, 6 and 12 months after the intervention will be conducted in a reference laboratory (FIOCRUZ). RESULTS The study is still recruiting participants and is expected to be completed in September 2020. CONCLUSIONS Our study seeks to analyze the response of anti-NDO-LID, HO-1/HMOX tests and serum IFN-γ concentration as a prophylactic measure after the use of single-dose rifampicin (SDR) combined with the Bacillus Calmette-Guérin vaccine (BCG) in home contacts of multibacillary leprosy cases. CLINICALTRIAL Brazilian Registry of Clinical Trials (ReBEC), RBR-6yg2z9. Retrospectively registered on 3 de Out. de 2019.


Author(s):  
James Peng ◽  
Jamin Liu ◽  
Sabrina A Mann ◽  
Anthea M Mitchell ◽  
Matthew T Laurie ◽  
...  

Abstract Background Sequencing of the SARS-CoV-2 viral genome from patient samples is an important epidemiological tool for monitoring and responding to the pandemic, including the emergence of new mutations in specific communities. Methods SARS-CoV-2genomicsequencesweregeneratedfrompositivesamplescollected,alongwithepidemiologicalmetadata,atawalk-up, rapid testing site in the Mission District of San Francisco, California during November 22-December 1, 2020 and January 10-29, 2021. Secondary household attack rates and mean sample viral load were estimated and compared across observed variants. Results A total of 12,124 tests were performed yielding 1,099 positives. From these, 928 high quality genomes were generated. Certain viral lineages bearing spike mutations, defined in part by L452R, S13I, and W152C, comprised 54.4% of the total sequences from January, compared to 15.7% in November. Household contacts exposed to the “California” or “West Coast” variants (B.1.427 and B.1.429) were at higher risk of infection compared to household contacts exposed to lineages lacking these variants (0.36 vs 0.29, RR=1.28; 95% CI:1.00-1.64). The reproductive number was estimated to be modestly higher than other lineages spreading in California during the second half of 2020. Viral loads were similar among persons infected with West Coast versus non-West Coast strains, as was the proportion of individuals with symptoms (60.9% vs 64.3%). Conclusions The increase in prevalence, relative household attack rates, and reproductive number are consistent with a modest transmissibility increase of the West Coast variants.


BMJ Open ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. e047210
Author(s):  
Anurag Bhargava ◽  
Madhavi Bhargava ◽  
Banurekha Velayutham ◽  
Kannan Thiruvengadam ◽  
Basilea Watson ◽  
...  

IntroductionIndia has the largest burden of cases and deaths related to tuberculosis (TB). Undernutrition is the leading risk factor accounting for TB incidence, while severe undernutrition is a common risk factor for mortality in patients with TB in India. The impact of nutritional supplementation on TB incidence is unknown, while few underpowered studies have assessed its impact on TB mortality. We designed an open-label, field-based cluster randomised trial to assess the impact of nutritional supplementation (with food rations) on TB incidence in a group at higher risk of TB infection and disease, viz household contacts (HHC) of patients with microbiologically confirmed pulmonary TB (PTB) in Jharkhand, a state with a high prevalence of undernutrition.Methods and analysisWe shall enrol 2800 adult patients with PTB of the national TB programme, across 28 treatment units in 4 districts, and their approximately 11 200 eligible contacts. The sample size has 80% power to detect the primary outcome of 50% reduction in incidence of active TB in HHC over 2 years of follow-up. Patients and HHC in both the arms will undergo nutritional assessment and counselling. Patients will receive monthly food rations (supplying 1200 kcal and 52 g proteins/day) and multivitamins along with antitubercular treatment. The HHC in the intervention arm will receive food rations (supplying 750 kcal and 23 g proteins/day) and multivitamins while HHC in control arm will be on usual diet. The secondary outcomes in HHC will include effects on nutritional status, non-TB infections. Secondary outcomes in patients are effects on TB mortality, adherence, adverse effects, nutritional and performance status. Substudies will examine micronutrient status and effects on dietary intake, body composition, muscle strength and immune function.Ethics and disseminationThe institutional ethics committee of ICMR-NIRT, Chennai, approved the study (289/NIRT-IEC/2018). The results will be disseminated in publications and presentations.Trial registration numberClinical Trial Registry of India: CTRI/2019/08/020490.


Author(s):  
Antti Kontturi ◽  
Satu Kekomäki ◽  
Eeva Ruotsalainen ◽  
Eeva Salo

AbstractTuberculosis (TB) risk is highest immediately after primary infection, and young children are vulnerable to rapid and severe TB disease. Contact tracing should identify infected children rapidly and simultaneously target resources effectively. We conducted a retrospective review of the paediatric TB contact tracing results in the Hospital District of Helsinki and Uusimaa from 2012 to 2016 and identified risk factors for TB disease or infection. Altogether, 121 index cases had 526 paediatric contacts of whom 34 were diagnosed with TB disease or infection. The maximum delay until first contact investigation visit among the household contacts under 5 years of age with either TB disease or infection was 7 days. The yield for TB disease or infection was 4.6% and 12.8% for household contacts, 0.5% and 0% for contacts exposed in a congregate setting and 1.4% and 5.0% for other contacts, respectively. Contacts born in a TB endemic country (aOR 3.07, 95% CI 1.10–8.57), with household exposure (aOR 2.96, 95% CI 1.33–6.58) or a sputum smear positive index case (aOR 3.96, 95% CI 1.20–13.03) were more likely to have TB disease or infection.Conclusions: Prompt TB investigations and early diagnosis can be achieved with a well-organised contact tracing structure. The risk for TB infection or disease was higher among contacts with household exposure, a sputum smear positive index case or born in a TB endemic country. Large-scale investigations among children exposed in congregate settings can result in a very low yield and should be cautiously targeted. What is Known:• Vulnerable young children are a high priority in contact tracing and should be evaluated as soon as possible after TB exposure What is New:• Prompt investigations for paediatric TB contacts and early diagnosis of infected children can be achieved with a well-organised contact tracing structure• Large-scale investigations among children exposed in congregate settings can result in a very low yield and should be cautiously targeted


Pathogens ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 911
Author(s):  
Marie Pouquet ◽  
Dorine Decarreaux ◽  
Pol Prévot-Monsacré ◽  
Corentin Hervé ◽  
Andréas Werner ◽  
...  

Background: The protocol study will focus on the seroprevalence of IgG antibodies to SARS-CoV-2 achieved by vaccination and/or natural protection as well as the history, symptoms, and risk factors for SARS-CoV-2 in four primary health-care workers (PHCWs) and their household contacts in metropolitan France. Methods: Here, we propose a protocol for a nationwide survey to determine the seroprevalence of IgG antibodies to SARS-CoV-2 achieved by vaccination and/or natural protection in four PHCW populations (general practitioners, pediatricians, pharmacists and assistants, and dentists and assistants) and their household contacts. Participants will be included from June to July 2021 (Phase 1) among PHCW populations located throughout metropolitan France. They will be asked to provide a range of demographic and behavioral information since the first SARS-CoV-2 wave and a self-sampled dried blood spot. Phase 1 will involve also a questionnaire and serological study of PHCWs’ household contacts. Seroprevalence will be estimated using two ELISAs designed to detect specific IgG antibodies to SARS-CoV-2 in humoral fluid, and these results will be confirmed using a virus neutralization test. This study will be repeated from November to December 2021 (Phase 2) to evaluate the evolution of immune status achieved by vaccination and/or natural protection of PHCWs and to describe the history of exposure to SARS-CoV-2.


Author(s):  
J A Hall ◽  
R J Harris ◽  
A Zaidi ◽  
S C Woodhall ◽  
G Dabrera ◽  
...  

Abstract Background Household transmission of SARS-CoV-2 is an important component of the community spread of the pandemic. Little is known about the factors associated with household transmission, at the level of the case, contact or household, or how these have varied over the course of the pandemic. Methods The Household Transmission Evaluation Dataset (HOSTED) is a passive surveillance system linking laboratory-confirmed COVID-19 cases to individuals living in the same household in England. We explored the risk of household transmission according to: age of case and contact, sex, region, deprivation, month and household composition between April and September 2020, building a multivariate model. Results In the period studied, on average, 5.5% of household contacts in England were diagnosed as cases. Household transmission was most common between adult cases and contacts of a similar age. There was some evidence of lower transmission rates to under-16s [adjusted odds ratios (aOR) 0.70, 95% confidence interval (CI) 0.66–0.74). There were clear regional differences, with higher rates of household transmission in the north of England and the Midlands. Less deprived areas had a lower risk of household transmission. After controlling for region, there was no effect of deprivation, but houses of multiple occupancy had lower rates of household transmission [aOR 0.74 (0.66–0.83)]. Conclusions Children are less likely to acquire SARS-CoV-2 via household transmission, and consequently there was no difference in the risk of transmission in households with children. Households in which cases could isolate effectively, such as houses of multiple occupancy, had lower rates of household transmission. Policies to support the effective isolation of cases from their household contacts could lower the level of household transmission.


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