scholarly journals Investigating the Impact of Asymptomatic Carriers on COVID-19 Transmission

2020 ◽  
Author(s):  
Jacob B. Aguilar ◽  
Jeremy Samuel Faust ◽  
Lauren M. Westafer ◽  
Juan B. Gutierrez
Keyword(s):  
Disease Surveillance ◽  
Reproduction Number ◽  
Clinical Symptoms ◽  
Communicable Disease ◽  
Average Rate ◽  
Point Estimate ◽  
Surveillance Systems ◽  
Average Case ◽  
Asymptomatic Carriers ◽  
The Impact

Coronavirus disease 2019 (COVID-19) is a novel human respiratory disease caused by the SARS-CoV-2 virus. Asymptomatic carriers of the virus display no clinical symptoms but are known to be contagious. Recent evidence reveals that this sub-population, as well as persons with mild disease, are a major contributor in the propagation of COVID-19. The asymptomatic sub-population frequently escapes detection by public health surveillance systems. Because of this, the currently accepted estimates of the basic reproduction number (ℛ0) of the disease are inaccurate. It is unlikely that a pathogen can blanket the planet in three months with an ℛ0 in the vicinity of 3, as reported in the literature (1–6). In this manuscript, we present a mathematical model taking into account asymptomatic carriers. Our results indicate that an initial value of the effective reproduction number could range from 5.5 to 25.4, with a point estimate of 15.4, assuming mean parameters. The first three weeks of the model exhibit exponential growth, which is in agreement with average case data collected from thirteen countries with universal health care and robust communicable disease surveillance systems; the average rate of growth in the number of reported cases is 23.3% per day during this period.

scholarly journals Community perspectives on the benefits and risks of technologically enhanced communicable disease surveillance systems: a report on four community juries

2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Chris Degeling ◽  
Stacy M. Carter ◽  
Antoine M. van Oijen ◽  
Jeremy McAnulty ◽  
Vitali Sintchenko ◽  
...  
Keyword(s):  
Disease Surveillance ◽  
Communicable Disease ◽  
Surveillance Systems ◽  
Community Perspectives

scholarly journals Analyses of the 1957 (Asian) influenza pandemic in the United Kingdom and the impact of school closures

2007 ◽  
Vol 136 (2) ◽  
pp. 166-179 ◽  
Author(s):  
E. VYNNYCKY ◽  
W. J. EDMUNDS
Keyword(s):  
United Kingdom ◽  
Reproduction Number ◽  
Clinical Symptoms ◽  
Influenza Pandemic ◽  
School Closures ◽  
Epidemic Size ◽  
The United Kingdom ◽  
Contact Patterns ◽  
Potential Impact ◽  
The Impact

SUMMARYMany countries plan to close schools during a future influenza pandemic, although the potential impact is poorly understood. We apply a model of the transmission dynamics of pandemic influenza to consultation, serological and clinical data from the United Kingdom from the 1957 (Asian) influenza pandemic, to estimate the basic reproduction number (R0), the proportion of infected individuals who experience clinical symptoms and the impact of school/nursery closures. The R0 for Asian influenza was about 1·8 and 60–65% of infected individuals were estimated to have experienced clinical symptoms. During a future pandemic, closure of schools/nurseries could reduce the epidemic size only by a very small amount (<10%) if R0 is high (e.g. 2·5 or 3·5), and modest reductions, e.g. 22% might be possible if it is low (1·8) and schools are closed early, depending on assumptions about contact patterns. Further data on contact patterns and their dependence on school closures are needed.

scholarly journals Global Landscape Review of Serotype-Specific Invasive Pneumococcal Disease Surveillance among Countries Using PCV10/13: The Pneumococcal Serotype Replacement and Distribution Estimation (PSERENADE) Project

2021 ◽  
Vol 9 (4) ◽  
pp. 742 ◽  
Author(s):  
Maria Deloria Knoll ◽  
Julia Bennett ◽  
Maria Garcia Quesada ◽  
Eunice Kagucia ◽  
Meagan Peterson ◽  
...  
Keyword(s):  
Invasive Pneumococcal Disease ◽  
Disease Surveillance ◽  
Pneumococcal Disease ◽  
Surveillance Systems ◽  
Eligibility Criteria ◽  
Distribution Estimation ◽  
Serotype Replacement ◽  
Pneumococcal Serotype ◽  
Adult Immunization ◽  
The Impact

Serotype-specific surveillance for invasive pneumococcal disease (IPD) is essential for assessing the impact of 10- and 13-valent pneumococcal conjugate vaccines (PCV10/13). The Pneumococcal Serotype Replacement and Distribution Estimation (PSERENADE) project aimed to evaluate the global evidence to estimate the impact of PCV10/13 by age, product, schedule, and syndrome. Here we systematically characterize and summarize the global landscape of routine serotype-specific IPD surveillance in PCV10/13-using countries and describe the subset that are included in PSERENADE. Of 138 countries using PCV10/13 as of 2018, we identified 109 with IPD surveillance systems, 76 of which met PSERENADE data collection eligibility criteria. PSERENADE received data from most (n = 63, 82.9%), yielding 240,639 post-PCV10/13 introduction IPD cases. Pediatric and adult surveillance was represented from all geographic regions but was limited from lower income and high-burden countries. In PSERENADE, 18 sites evaluated PCV10, 42 PCV13, and 17 both; 17 sites used a 3 + 0 schedule, 38 used 2 + 1, 13 used 3 + 1, and 9 used mixed schedules. With such a sizeable and generally representative dataset, PSERENADE will be able to conduct robust analyses to estimate PCV impact and inform policy at national and global levels regarding adult immunization, schedule, and product choice, including for higher valency PCVs on the horizon.

scholarly journals Protocol: Leveraging a demographic and health surveillance system for Covid-19 Surveillance in rural KwaZulu-Natal

2020 ◽  
Vol 5 ◽  
pp. 109 ◽  
Author(s):  
Mark J. Siedner ◽  
Guy Harling ◽  
Anne Derache ◽  
Theresa Smit ◽  
Thandeka Khoza ◽  
...  
Keyword(s):  
Disease Surveillance ◽  
Surveillance Program ◽  
Surveillance Systems ◽  
Risk Minimization ◽  
Middle Income ◽  
Resource Limited ◽  
Kwazulu Natal ◽  
Public Sector Health ◽  
Demographic Surveillance Systems ◽  
The Impact

A coordinated system of disease surveillance will be critical to effectively control the coronavirus disease 2019 (Covid-19) pandemic. Such systems enable rapid detection and mapping of epidemics and inform allocation of scarce prevention and intervention resources. Although many lower- and middle-income settings lack infrastructure for optimal disease surveillance, health and demographic surveillance systems (HDSS) provide a unique opportunity for epidemic monitoring. This protocol describes a surveillance program at the Africa Health Research Institute’s Population Intervention Platform site in northern KwaZulu-Natal. The program leverages a longstanding HDSS in a rural, resource-limited setting with very high prevalence of HIV and tuberculosis to perform Covid-19 surveillance. Our primary aims include: describing the epidemiology of the Covid-19 epidemic in rural KwaZulu-Natal; determining the impact of the Covid-19 outbreak and non-pharmaceutical control interventions (NPI) on behaviour and wellbeing; determining the impact of HIV and tuberculosis on Covid-19 susceptibility; and using collected data to support the local public-sector health response. The program involves telephone-based interviews with over 20,000 households every four months, plus a sub-study calling 750 households every two weeks. Each call asks a household representative how the epidemic and NPI are affecting the household and conducts a Covid-19 risk screen for all resident members. Any individuals screening positive are invited to a clinical screen, potential test and referral to necessary care – conducted in-person near their home following careful risk minimization procedures. In this protocol we report the details of our cohort design, questionnaires, data and reporting structures, and standard operating procedures in hopes that our project can inform similar efforts elsewhere.

Establishing communicable disease surveillance systems

2021 ◽  
pp. bmjmilitary-2021-001803
Author(s):  
Thomas Falconer Hall ◽  
D A Ross
Keyword(s):  
Data Collection ◽  
Disease Surveillance ◽  
Communicable Disease ◽  
Control Measures ◽  
Public Health Approach ◽  
Recent Experience ◽  
Surveillance Systems ◽  
Military Health ◽  
Humanitarian Emergencies ◽  
Disaster Relief Operations

Humanitarian emergencies can result in an increase of communicable diseases, leading to a rise in mortality and/or morbidity in vulnerable populations. This requires a public health approach to re-establish control of communicable disease. Communicable disease surveillance systems play a key role, providing the information required for disease control measures, through systematic data collection, analysis, interpretation and dissemination. In humanitarian emergencies, they use the principles, practices and processes of wider surveillance systems, while being more focused on urgent priorities. However, communicable disease surveillance systems in humanitarian emergencies are constrained by multiple environmental, epidemiological and sociopolitical factors. Basic data collection, the bedrock of surveillance systems, can be extremely challenging and may require additional methods to estimate population size and prioritise diseases. Surveillance systems may be operating in conditions of weak state capacity with little physical or institutional infrastructure to support their operation. However, there are examples of successful self-sustaining disease surveillance systems in these circumstances, such as the deployment of WHO’s Early Warning Alert and Response System in a Box. Individuals and organisations charged with establishing communicable disease surveillance systems in emergencies would be well advised to learn from recent examples of success, use the sources of planning guidance outlined in this article and seek advice from organisations with recent experience. This is a paper commissioned as a part of the Humanitarian and Disaster Relief Operations special issue of BMJ Military Health.

scholarly journals Is group C meningococcal disease increasing in Europe? A report of surveillance of meningococcal infection in Europe 1993–6

1999 ◽  
Vol 122 (1) ◽  
pp. 41-49 ◽  
Author(s):  
M. CONNOLLY ◽  
N. NOAH
Keyword(s):  
Meningococcal Disease ◽  
Disease Surveillance ◽  
Communicable Disease ◽  
Age Distribution ◽  
Case Fatality ◽  
European Countries ◽  
Meningococcal Infection ◽  
Slow Increase ◽  
Set Up ◽  
The Impact

A surveillance system to assess the impact and changing epidemiology of invasive meningococcal disease in Europe was set up in 1987. Since about 1991, contributors from national reference laboratories, national communicable disease surveillance centres and institutes of public health in 35 European countries provided information on all reported cases of meningococcal disease in their country. We describe some trends observed over the period 1993–6. The main findings were: the overall incidence of meningococcal disease was 1·1 per 100000 population but there was some evidence of a slow increase over time and with northern European countries tending to have a higher incidence (Kendall correlation 0·5772, P<0·001), an increasing predominance of serogroup C, and a shift in the age distribution towards teenagers and away from younger children (χ2 test for trend 44·56, P<0·0001), although about half of the cases were under 5 years of age. The overall case fatality rate was 8·3% and the most common serosubtypes were B[ratio ]15[ratio ]P1.7,16 and C[ratio ]2a[ratio ]P1.2,5.

scholarly journals Institutionalising wastewater surveillance systems to minimise the impact of COVID-19: cases of Indonesia, Japan and Viet Nam

2020 ◽  
Author(s):  
T. Takeda ◽  
M. Kitajima ◽  
N. T. T. Huong ◽  
A. S. Setiyawan ◽  
T. Setiadi ◽  
...  
Keyword(s):  
Surveillance System ◽  
Disease Surveillance ◽  
Current Status ◽  
Viet Nam ◽  
Surveillance Systems ◽  
Rapid Rate ◽  
Disease Surveillance System ◽  
The Impact ◽  
Potential Tool ◽  
Actual Prevalence

Abstract This mini review describes the current status and challenges regarding institutionalisation of wastewater surveillance systems against COVID-19. Monitoring SARS-CoV-2 in wastewater has been proposed to be a potential tool to understand the actual prevalence of COVID-19 in the community, and it could be an effective approach to monitor the trend during the COVID-19 pandemic. However, challenges to institutionalise wastewater surveillance systems are still abundant and unfolding at a rapid rate given that the international understanding regarding the scientific knowledge and socio-political impacts of COVID-19 are in the developing stages. To better understand the existing challenges and bottlenecks, a comparative study between Japan, Viet Nam, and Indonesia was carried out in the present study. Through gaining a better understanding of common issues as well as issues specific to each country, we hope to contribute to building a robust multistakeholder system to monitor SARS-CoV-2 in wastewater as an effective disease surveillance system for COVID-19.

scholarly journals Advances in spatiotemporal models for non-communicable disease surveillance

2020 ◽  
Vol 49 (Supplement_1) ◽  
pp. i26-i37
Author(s):  
Marta Blangiardo ◽  
Areti Boulieri ◽  
Peter Diggle ◽  
Frédéric B Piel ◽  
Gavin Shaddick ◽  
...  
Keyword(s):  
Disease Surveillance ◽  
Communicable Disease ◽  
Surveillance Systems ◽  
Complex Data ◽  
Bayesian Hierarchical ◽  
Complex Models ◽  
Intervention Policy ◽  
Spatiotemporal Models ◽  
Modelling Process ◽  
Non Communicable Disease

Abstract Surveillance systems are commonly used to provide early warning detection or to assess an impact of an intervention/policy. Traditionally, the methodological and conceptual frameworks for surveillance have been designed for infectious diseases, but the rising burden of non-communicable diseases (NCDs) worldwide suggests a pressing need for surveillance strategies to detect unusual patterns in the data and to help unveil important risk factors in this setting. Surveillance methods need to be able to detect meaningful departures from expectation and exploit dependencies within such data to produce unbiased estimates of risk as well as future forecasts. This has led to the increasing development of a range of space-time methods specifically designed for NCD surveillance. We present an overview of recent advances in spatiotemporal disease surveillance for NCDs, using hierarchically specified models. This provides a coherent framework for modelling complex data structures, dealing with data sparsity, exploiting dependencies between data sources and propagating the inherent uncertainties present in both the data and the modelling process. We then focus on three commonly used models within the Bayesian Hierarchical Model (BHM) framework and, through a simulation study, we compare their performance. We also discuss some challenges faced by researchers when dealing with NCD surveillance, including how to account for false detection and the modifiable areal unit problem. Finally, we consider how to use and interpret the complex models, how model selection may vary depending on the intended user group and how best to communicate results to stakeholders and the general public.

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