scholarly journals The Efficacy of Contact Tracing for the Containment of the 2019 Novel Coronavirus (COVID-19)

2020 ◽  
Author(s):  
Matt J Keeling ◽  
T Déirdre Hollingsworth ◽  
Jonathan M Read
Keyword(s):  
Close Contact ◽  
Control Measure ◽  
Disease Outbreaks ◽  
Contact Tracing ◽  
Public Health Response ◽  
Central Public Health ◽  
Increased Risk ◽  
Definition Of ◽  
Novel Coronavirus ◽  
The Impact

Contact tracing is a central public health response to infectious disease outbreaks, especially in the early stages of an outbreak when specific treatments are limited. Importation of novel Coronavirus (COVID-19) from China and elsewhere into the United Kingdom highlights the need to understand the impact of contact tracing as a control measure. Using detailed survey information on social encounters coupled to predictive models, we investigate the likely efficacy of the current UK definition of a close contact (within 2 meters for 15 minutes or more) and the distribution of secondary cases that may go untraced. Taking recent estimates for COVID-19 transmission, we show that less than 1 in 5 cases will generate any subsequent untraced cases, although this comes at a high logistical burden with an average of 36.1 individuals (95th percentiles 0-182) traced per case. Changes to the definition of a close contact can reduce this burden, but with increased risk of untraced cases; we estimate that any definition where close contact requires more than 4 hours of contact is likely to lead to uncontrolled spread.

scholarly journals Efficacy of contact tracing for the containment of the 2019 novel coronavirus (COVID-19)

2020 ◽  
pp. jech-2020-214051 ◽  
Author(s):  
Matt J Keeling ◽  
T Deirdre Hollingsworth ◽  
Jonathan M Read
Keyword(s):  
Close Contact ◽  
Control Measure ◽  
Disease Outbreaks ◽  
Contact Tracing ◽  
Public Health Response ◽  
Central Public Health ◽  
Increased Risk ◽  
Novel Coronavirus ◽  
The Uk ◽  
The Impact

ObjectiveContact tracing is a central public health response to infectious disease outbreaks, especially in the early stages of an outbreak when specific treatments are limited. Importation of novel coronavirus (COVID-19) from China and elsewhere into the UK highlights the need to understand the impact of contact tracing as a control measure.DesignDetailed survey information on social encounters from over 5800 respondents is coupled to predictive models of contact tracing and control. This is used to investigate the likely efficacy of contact tracing and the distribution of secondary cases that may go untraced.ResultsTaking recent estimates for COVID-19 transmission we predict that under effective contact tracing less than 1 in 6 cases will generate any subsequent untraced infections, although this comes at a high logistical burden with an average of 36 individuals traced per case. Changes to the definition of a close contact can reduce this burden, but with increased risk of untraced cases; we find that tracing using a contact definition requiring more than 4 hours of contact is unlikely to control spread.ConclusionsThe current contact tracing strategy within the UK is likely to identify a sufficient proportion of infected individuals such that subsequent spread could be prevented, although the ultimate success will depend on the rapid detection of cases and isolation of contacts. Given the burden of tracing a large number of contacts to find new cases, there is the potential the system could be overwhelmed if imports of infection occur at a rapid rate.

scholarly journals Digital proximity tracing on empirical contact networks for pandemic control

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
G. Cencetti ◽  
G. Santin ◽  
A. Longa ◽  
E. Pigani ◽  
A. Barrat ◽  
...  
Keyword(s):  
Large Scale ◽  
Disease Outbreaks ◽  
Physical Distance ◽  
Contact Tracing ◽  
Reproductive Number ◽  
Modeling Framework ◽  
Infectious Disease Outbreaks ◽  
Contact Patterns ◽  
Contact Data ◽  
The Impact

AbstractDigital contact tracing is a relevant tool to control infectious disease outbreaks, including the COVID-19 epidemic. Early work evaluating digital contact tracing omitted important features and heterogeneities of real-world contact patterns influencing contagion dynamics. We fill this gap with a modeling framework informed by empirical high-resolution contact data to analyze the impact of digital contact tracing in the COVID-19 pandemic. We investigate how well contact tracing apps, coupled with the quarantine of identified contacts, can mitigate the spread in real environments. We find that restrictive policies are more effective in containing the epidemic but come at the cost of unnecessary large-scale quarantines. Policy evaluation through their efficiency and cost results in optimized solutions which only consider contacts longer than 15–20 minutes and closer than 2–3 meters to be at risk. Our results show that isolation and tracing can help control re-emerging outbreaks when some conditions are met: (i) a reduction of the reproductive number through masks and physical distance; (ii) a low-delay isolation of infected individuals; (iii) a high compliance. Finally, we observe the inefficacy of a less privacy-preserving tracing involving second order contacts. Our results may inform digital contact tracing efforts currently being implemented across several countries worldwide.

scholarly journals 368. Clinical Characteristics of Hospitalized COVID-19 American Indian Patients in Rural Arizona

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S253-S254
Author(s):  
Amy Nham ◽  
Ryan M Close
Keyword(s):  
American Indians ◽  
Median Number ◽  
Clinic Visit ◽  
Contact Tracing ◽  
Shortness Of Breath ◽  
Early Referral ◽  
Increased Risk ◽  
Wbc Count ◽  
The Impact ◽  
D Dimer

Abstract Background American Indians have an increased risk of serious complications from COVID-19 due to the high prevalence of comorbidities such as diabetes, heart disease, obesity, and asthma. To date, there has been limited analysis of COVID-19 in the AI population. This study describes the characteristics of hospitalized COVID-19 patients from a well-defined AI population in eastern Arizona. Additionally, we explored the impact of early referral via contact tracing versus those who self-presented. Methods Retrospective chart reviews were completed for patients hospitalized for COVID from March 29 to May 16, 2020. Summary statistics were used to describe demographics, symptoms, pre-existing conditions, and hospitalization data. Results We observed 447 laboratory-confirmed cases of COVID-19, resulting in 71 (15.9%) hospitalizations over a 7-week period and a hospitalization rate of 159 per 1,000 persons. Of the 50 hospitalizations reviewed sequentially, 56% were female, median age of 55 (IQR 44–65). Median number of days hospitalized was 4 (2–6), with 16% requiring intensive care unit support, 15% intubated, 12% readmitted, and 10% deceased. 67% had an epidemiological link, and 32% had an emergency department or outpatient clinic visit within 7 days of hospitalization. All patients were symptomatic; the most common symptoms were cough (90%), shortness of breath (78%), and subjective fever (66%). 86% of patients had a pre-existing condition; the most common pre-existing conditions were diabetes (66%), obesity (58%), and hypertension (52%, Figure 1). All patients had elevated LDH, 94% had elevated CRP, 86% had elevated d-dimer, and 40% had lymphopenia; only 10% had an elevated WBC count and 26% had thrombocytopenia (Table 1). 26% of the patients were referred in by the tracing team (Table 2). Analysis of 500 hospitalizations will be available in October 2020. Conclusion Most AI patients hospitalized had a pre-existing condition, symptoms of cough or shortness of breath, and elevated LDH, CRP, and d-dimer. More research is needed to understand the patterns of COVID-19 related disease in vulnerable populations, like AI/AN, and to examine the utility of early referral by contact tracing teams in rural settings which may guide future tracing strategies. Disclosures All Authors: No reported disclosures

scholarly journals Effect of COVID-19 on childhood Mycoplasma pneumoniae infection in Chengdu, China

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Ying Zhang ◽  
Yijie Huang ◽  
Tao Ai ◽  
Jun Luo ◽  
Hanmin Liu
Keyword(s):  
Public Health ◽  
Mycoplasma Pneumoniae ◽  
Close Contact ◽  
Serum Antibody ◽  
Pathogen Transmission ◽  
Western China ◽  
Public Health Response ◽  
The Public ◽  
Health Response ◽  
The Impact

Abstract Background Following the outbreak of the COVID-19 pandemic, a change in the incidence and transmission of respiratory pathogens was observed. Here, we retrospectively analyzed the impact of COVID-19 on the epidemiologic characteristics of Mycoplasma pneumoniae infection among children in Chengdu, one of the largest cities of western China. Method M. pneumoniae infection was diagnosed in 33,345 pediatric patients with respiratory symptoms at the Chengdu Women’s & Children’s Central Hospital between January 2017 and December 2020, based on a serum antibody titer of ≥1:160 measured by the passive agglutination assay. Differences in infection rates were examined by sex, age, and temporal distribution. Results Two epidemic outbreaks occurred between October-December 2017 and April-December 2019, and two infection peaks were detected in the second and fourth quarters of 2017, 2018, and 2019. Due to the public health response to COVID-19, the number of positive M. pneumoniae cases significantly decreased in the second quarter of 2020. The number of M. pneumoniae infection among children aged 3–6 years was higher than that in other age groups. Conclusions Preschool children are more susceptible to M. pneumoniae infection and close contact appears to be the predominant factor favoring pathogen transmission. The public health response to COVID-19 can effectively control the transmission of M. pneumoniae.

Impact of the Ebola epidemic on clinical outcomes of HIV-infected soldiers and their dependents in Sierra Leone

2018 ◽  
Vol 30 (2) ◽  
pp. 106-112 ◽  
Author(s):  
Elizabeth Nagel ◽  
Michael J Blackowicz ◽  
Foday Sahr ◽  
Olamide D Jarrett
Keyword(s):  
Clinical Outcomes ◽  
Sierra Leone ◽  
Repeated Measures ◽  
Disease Outbreaks ◽  
Armed Forces ◽  
Hiv Treatment ◽  
Hiv Care ◽  
Increased Risk ◽  
The Republic ◽  
The Impact

The impact of the 2014–2016 Ebola epidemic in West Africa on human immunodeficiency virus (HIV) treatment in Sierra Leone is unknown, especially for groups with higher HIV prevalence such as the military. Using a retrospective study design, clinical outcomes were evaluated prior to and during the epidemic for 264 HIV-infected soldiers of the Republic of Sierra Leone Armed Forces (RSLAF) and their dependents receiving HIV treatment at the primary RSLAF HIV clinic. Medical records were abstracted for baseline clinical data and clinic attendance. Estimated risk of lost to follow-up (LTFU), default, and number of days without antiretroviral therapy (DWA) were calculated using repeated measures general estimating equations adjusted for age and gender. Due to missing data, 262 patients were included in the final analyses. There was higher risk of LTFU throughout the Ebola epidemic in Sierra Leone compared to the pre-Ebola baseline, with the largest increase in LTFU risk occurring at the peak of the epidemic (relative risk: 3.22, 95% CI: 2.22–4.67). There was an increased risk of default and DWA during the Ebola epidemic for soldiers but not for their dependents. The risk of LTFU, default, and DWA stabilized once the epidemic was largely resolved but remained elevated compared to the pre-Ebola baseline. Our findings demonstrate the negative and potentially lasting impact of the Ebola epidemic on HIV care in Sierra Leone and highlight the need to develop strategies to minimize disruptions in HIV care with future disease outbreaks.

scholarly journals Systematic Review on Food Safety and Supply Chain Risk Assessment Post Pandemic: Malaysian Perspective

2021 ◽  
Vol 5 ◽  
Author(s):  
Md Saad Nurul Eiman ◽  
Firdaus Muhammad Nurul Azmi Aida ◽  
Trias Mahmudiono ◽  
Siva Raseetha
Keyword(s):  
Supply Chain ◽  
Food Safety ◽  
Food Supply ◽  
Small Scale ◽  
Supply Chain Risk ◽  
Food Supply Chain ◽  
Economic Sectors ◽  
Definition Of ◽  
Novel Coronavirus ◽  
The Impact

The novel coronavirus disease 2019, or COVID-19, is a recent disease that has struck the entire world. This review is conducted to study the impacts of the COVID-19 pandemic to food safety as well as the food supply chain. The pandemic has caused various changes around the world as numerous countries and governments have implemented lockdowns and restrictions to help curb the rising cases due to COVID-19. However, these restrictions have impacted many aspects of everyday life, including the economic sectors such as the food industry. An overview of the current COVID-19 situation in Malaysia was discussed in this review along with its implication on food safety and food supply chain. This is followed by a discussion on the definition of food safety, the impact of the pandemic to food safety, as well as the steps to be taken to ensure food safety. Hygiene of food handlers, complete vaccination requirement, kitchen sanitation and strict standard operating procedures (SOPs) should be in place to ensure the safety of food products, either in food industries or small scale business. Additionally, the aspect of the food supply chain was also discussed, including the definition of the food supply chain and the impact of COVID-19 to the food supply chain. Travel restriction and lack of manpower had impacted the usual operation and production activities. Lack of customers and financial difficulties to sustain business operational costs had even resulted in business closure. As a conclusion, this article provides insight into crucial factors that need to be considered to effectively contain COVID-19 cases and highlights the precaution methods to be taken through continuous monitoring and implementation by Malaysian government.

scholarly journals Ethics of instantaneous contact tracing using mobile phone apps in the control of the COVID-19 pandemic

2020 ◽  
Vol 46 (7) ◽  
pp. 427-431 ◽  
Author(s):  
Michael J Parker ◽  
Christophe Fraser ◽  
Lucie Abeler-Dörner ◽  
David Bonsall
Keyword(s):  
Public Health ◽  
Infectious Disease ◽  
Mobile Phone ◽  
Public Health Practice ◽  
Disease Outbreaks ◽  
Contact Tracing ◽  
Mobile Phone Data ◽  
Public Health Response ◽  
Infectious Disease Outbreaks ◽  
Ethical Implications

In this paper we discuss ethical implications of the use of mobile phone apps in the control of the COVID-19 pandemic. Contact tracing is a well-established feature of public health practice during infectious disease outbreaks and epidemics. However, the high proportion of pre-symptomatic transmission in COVID-19 means that standard contact tracing methods are too slow to stop the progression of infection through the population. To address this problem, many countries around the world have deployed or are developing mobile phone apps capable of supporting instantaneous contact tracing. Informed by the on-going mapping of ‘proximity events’ these apps are intended both to inform public health policy and to provide alerts to individuals who have been in contact with a person with the infection. The proposed use of mobile phone data for ‘intelligent physical distancing’ in such contexts raises a number of important ethical questions. In our paper, we outline some ethical considerations that need to be addressed in any deployment of this kind of approach as part of a multidimensional public health response. We also, briefly, explore the implications for its use in future infectious disease outbreaks.

scholarly journals The revised definition of pulmonary hypertension: exploring the impact on patient management

2019 ◽  
Vol 21 (Supplement_K) ◽  
pp. K4-K8 ◽  
Author(s):  
Gérald Simonneau ◽  
Marius M Hoeper
Keyword(s):  
Pulmonary Hypertension ◽  
Scientific Evidence ◽  
Management Strategies ◽  
Pulmonary Vascular Disease ◽  
Close Monitoring ◽  
Mean Pulmonary Arterial Pressure ◽  
Increased Risk ◽  
Patient Groups ◽  
Definition Of ◽  
The Impact

Abstract At the 6th World Symposium on Pulmonary Hypertension (PH), it was proposed that the mean pulmonary arterial pressure (mPAP) threshold used to define PH should be lowered from ≥25 mmHg to >20 mmHg. The rationale for this change is that the ≥25 mmHg threshold is arbitrary, whereas the revised threshold is based on scientific evidence. For the definition of all forms of pre-capillary PH, the inclusion of a pulmonary vascular resistance (PVR) ≥3 Wood Units was also proposed, placing greater emphasis on an elevated PVR to identify pulmonary vascular disease. Here, we discuss the possible impact of the revised definition of PH on future clinical management. This change may facilitate earlier PH detection, particularly in at-risk patient groups that are already undergoing screening programmes, e.g. those with systemic sclerosis or mutations associated with PH. As an mPAP above the upper limit of normal (>20 mmHg) but <25 mmHg is associated with increased risk of morbidity and mortality compared with a normal mPAP, early identification of patients in this group is important to enable close monitoring and timely treatment initiation once clinically indicated. Treatments currently approved for PH are not necessarily suitable for patients with an mPAP 21–24 mmHg, as the management of this group has not been widely examined. The revised definition may facilitate inclusion of these patients in prospective trials, allowing the evaluation of appropriate management strategies.

scholarly journals Digital Proximity Tracing in the COVID-19 Pandemic on Empirical Contact Networks

2020 ◽  
Author(s):  
Giulia Cencetti ◽  
Gabriele Santin ◽  
Antonio Longa ◽  
Emanuele Pigani ◽  
Alain Barrat ◽  
...  
Keyword(s):  
Disease Outbreaks ◽  
Contact Tracing ◽  
Reproductive Number ◽  
Modeling Framework ◽  
Effective Measure ◽  
Epidemic Dynamics ◽  
Contact Patterns ◽  
Contact Data ◽  
High Level ◽  
The Impact

Abstract Digital contact tracing is increasingly considered as a tool to control infectious disease outbreaks. As part of a broader test, trace, isolate, and quarantine strategy, digital contract tracing apps have been proposed to alleviate lock-downs, and to return societies to a more normal situation in the ongoing COVID-19 crisis. Early work evaluating digital contact tracing did not consider important features and heterogeneities present in real-world contact patterns which impact epidemic dynamics. Here, we fill this gap by considering a modeling framework informed by empirical high-resolution contact data to analyze the impact of digital contact tracing apps in the COVID-19 pandemic. We investigate how well contact tracing apps, coupled with the quarantine of identified contacts, can mitigate the spread of COVID-19 in realistic scenarios such as a university campus, a workplace, or a high school. We find that restrictive policies are more effective in confining the epidemics but come at the cost of quarantining a large part of the population. It is possible to avoid this effect by considering less strict policies, which only consider contacts with longer exposure and at shorter distance to be at risk. Our results also show that isolation and tracing can help keep re-emerging outbreaks under control provided that hygiene and social distancing measures limit the reproductive number to 1.5. Moreover, we confirm that a high level of app adoption is crucial to make digital contact tracing an effective measure. Our results may inform app-based contact tracing efforts currently being implemented across several countries worldwide.

scholarly journals A modelling framework to assess the likely effectiveness of facemasks in combination with ‘lock-down’ in managing the COVID-19 pandemic

2020 ◽  
Vol 476 (2238) ◽  
pp. 20200376 ◽  
Author(s):  
Richard O. J. H. Stutt ◽  
Renata Retkute ◽  
Michael Bradley ◽  
Christopher A. Gilligan ◽  
John Colvin
Keyword(s):  
Mobile Apps ◽  
Population Level ◽  
Disease Spread ◽  
Contact Tracing ◽  
Lower Efficiency ◽  
The Public ◽  
Molecular Tests ◽  
Modelling Framework ◽  
Increased Risk ◽  
The Impact

COVID-19 is characterized by an infectious pre-symptomatic period, when newly infected individuals can unwittingly infect others. We are interested in what benefits facemasks could offer as a non-pharmaceutical intervention, especially in the settings where high-technology interventions, such as contact tracing using mobile apps or rapid case detection via molecular tests, are not sustainable. Here, we report the results of two mathematical models and show that facemask use by the public could make a major contribution to reducing the impact of the COVID-19 pandemic. Our intention is to provide a simple modelling framework to examine the dynamics of COVID-19 epidemics when facemasks are worn by the public, with or without imposed ‘lock-down’ periods. Our results are illustrated for a number of plausible values for parameter ranges describing epidemiological processes and mechanistic properties of facemasks, in the absence of current measurements for these values. We show that, when facemasks are used by the public all the time (not just from when symptoms first appear), the effective reproduction number, R e , can be decreased below 1, leading to the mitigation of epidemic spread. Under certain conditions, when lock-down periods are implemented in combination with 100% facemask use, there is vastly less disease spread, secondary and tertiary waves are flattened and the epidemic is brought under control. The effect occurs even when it is assumed that facemasks are only 50% effective at capturing exhaled virus inoculum with an equal or lower efficiency on inhalation. Facemask use by the public has been suggested to be ineffective because wearers may touch their faces more often, thus increasing the probability of contracting COVID-19. For completeness, our models show that facemask adoption provides population-level benefits, even in circumstances where wearers are placed at increased risk. At the time of writing, facemask use by the public has not been recommended in many countries, but a recommendation for wearing face-coverings has just been announced for Scotland. Even if facemask use began after the start of the first lock-down period, our results show that benefits could still accrue by reducing the risk of the occurrence of further COVID-19 waves. We examine the effects of different rates of facemask adoption without lock-down periods and show that, even at lower levels of adoption, benefits accrue to the facemask wearers. These analyses may explain why some countries, where adoption of facemask use by the public is around 100%, have experienced significantly lower rates of COVID-19 spread and associated deaths. We conclude that facemask use by the public, when used in combination with physical distancing or periods of lock-down, may provide an acceptable way of managing the COVID-19 pandemic and re-opening economic activity. These results are relevant to the developed as well as the developing world, where large numbers of people are resource poor, but fabrication of home-made, effective facemasks is possible. A key message from our analyses to aid the widespread adoption of facemasks would be: ‘my mask protects you, your mask protects me’.

Sign in / Sign up

Export Citation Format

Share Document