Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 20 de 185
Filter
1.
Bull Math Biol ; 84(6): 66, 2022 May 13.
Article in English | MEDLINE | ID: covidwho-1844446

ABSTRACT

Testing individuals for pathogens can affect the spread of epidemics. Understanding how individual-level processes of sampling and reporting test results can affect community- or population-level spread is a dynamical modeling question. The effect of testing processes on epidemic dynamics depends on factors underlying implementation, particularly testing intensity and on whom testing is focused. Here, we use a simple model to explore how the individual-level effects of testing might directly impact population-level spread. Our model development was motivated by the COVID-19 epidemic, but has generic epidemiological and testing structures. To the classic SIR framework we have added a per capita testing intensity, and compartment-specific testing weights, which can be adjusted to reflect different testing emphases-surveillance, diagnosis, or control. We derive an analytic expression for the relative reduction in the basic reproductive number due to testing, test-reporting and related isolation behaviours. Intensive testing and fast test reporting are expected to be beneficial at the community level because they can provide a rapid assessment of the situation, identify hot spots, and may enable rapid contact-tracing. Direct effects of fast testing at the individual level are less clear, and may depend on how individuals' behaviour is affected by testing information. Our simple model shows that under some circumstances both increased testing intensity and faster test reporting can reduce the effectiveness of control, and allows us to explore the conditions under which this occurs. Conversely, we find that focusing testing on infected individuals always acts to increase effectiveness of control.


Subject(s)
COVID-19 , Epidemics , COVID-19/diagnosis , COVID-19/epidemiology , Epidemics/prevention & control , Humans , Mathematical Concepts , Models, Biological , SARS-CoV-2
2.
J R Soc Interface ; 19(190): 20220048, 2022 May.
Article in English | MEDLINE | ID: covidwho-1831585

ABSTRACT

Effective contact tracing is crucial to containing epidemic spreading without disrupting societal activities, especially during a pandemic. Large gatherings play a key role, potentially favouring superspreading events. However, the effects of tracing in large groups have not been fully assessed so far. We show that in addition to forward tracing, which reconstructs to whom the disease spreads, and backward tracing, which searches from whom the disease spreads, a third 'sideward' tracing is always present, when tracing gatherings. This is an indirect tracing that detects infected asymptomatic individuals, even if they have been neither directly infected by nor directly transmitted the infection to the index case. We analyse this effect in a model of epidemic spreading for SARS-CoV-2, within the framework of simplicial activity-driven temporal networks. We determine the contribution of the three tracing mechanisms to the suppression of epidemic spreading, showing that sideward tracing induces a non-monotonic behaviour in the tracing efficiency, as a function of the size of the gatherings. Based on our results, we suggest an optimal choice for the sizes of the gatherings to be traced and we test the strategy on an empirical dataset of gatherings on a university campus.


Subject(s)
COVID-19 , Epidemics , COVID-19/epidemiology , COVID-19/prevention & control , Contact Tracing/methods , Epidemics/prevention & control , Humans , Pandemics/prevention & control , SARS-CoV-2 , Universities
3.
Zhonghua Liu Xing Bing Xue Za Zhi ; 43(4): 466-477, 2022 Apr 10.
Article in Chinese | MEDLINE | ID: covidwho-1810386

ABSTRACT

The COVID-19 pandemic is still ongoing in the world, the risk of COVID-19 spread from other countries or in the country will exist for a long term in China. In the routine prevention and control phase, a number of local COVID-19 epidemics have occurred in China, most COVID-19 cases were sporadic ones, but a few case clusters or outbreaks were reported. Winter and spring were the seasons with high incidences of the epidemics; border and port cities had higher risk for outbreaks. Active surveillance in key populations was an effective way for the early detection of the epidemics. Through a series of comprehensive prevention and control measures, including mass nucleic acid screening, close contact tracing and isolation, classified management of areas and groups at risk, wider social distancing and strict travel management, the local COVID-19 epidemics have been quickly and effectively controlled. The experiences obtained in the control of the local epidemics would benefit the routine prevention and control of COVID-19 in China. The occurrence of a series of COVID-19 case clusters or outbreaks has revealed the weakness or deficiencies in the COVID-19 prevention and control in China, so this paper suggests some measures for the improvement of the future prevention and control of COVID-19.


Subject(s)
COVID-19 , Epidemics , COVID-19/epidemiology , COVID-19/prevention & control , China/epidemiology , Contact Tracing , Epidemics/prevention & control , Humans , Pandemics/prevention & control , SARS-CoV-2
4.
Nat Biotechnol ; 40(3): 301-302, 2022 03.
Article in English | MEDLINE | ID: covidwho-1805636
5.
Comput Math Methods Med ; 2022: 5693293, 2022.
Article in English | MEDLINE | ID: covidwho-1789046

ABSTRACT

This research was aimed at exploring the construction and evaluation method of the comprehensive emergency response system for public health emergencies under the COVID-19 (coronavirus disease 2019) epidemic situation based on discrete stochastic mathematical model. The response of the Centers for Disease Control and Prevention (CDCP) of Taiyuan city in the COVID-19 epidemic situation was taken as an example. A new discrete stochastic COVID-19 epidemic spread mathematical model which integrated public health intervention and input cases was proposed. The model was parameterized by multisource data, and the impact of different flow patterns on the risk of secondary outbreak was analyzed. The advantages and disadvantages of its emergency system construction were analyzed. Additionally, the improvement measures and suggestions for the existing problems were proposed. Results suggested that there was only one specialized disease prevention and control institution in Taiyuan, and there were only 11 centers for disease prevention and control, accounting for 6.2% (11/177) of the total in Shanxi Province. Through the analysis, it was found that the current public health emergency response system in Taiyuan city had imperfect management coordination mechanism, incomplete plan type, serious shortage of public health personnel, poor information communication efficiency, insufficient early warning efficiency of the epidemic detection system, and weak logistics material security links. Therefore, it was proposed to establish a sound coordination system of emergency health management and vigorously promote the construction of emergency health management institutions. Thus, a public health emergency management system integrating management coordination system, plan system, emergency team building system, material reserve management, and other functions was formed. The application of discrete stochastic mathematical model suggests that intermittent population flow and effective isolation of infected people in transient population can effectively reduce the risk of secondary outbreak. The system analysis here also provides theoretical basis for improving the construction of public health emergency response system in Taiyuan.


Subject(s)
COVID-19 , Epidemics , COVID-19/epidemiology , COVID-19/prevention & control , China/epidemiology , Disease Outbreaks/prevention & control , Epidemics/prevention & control , Humans , Models, Theoretical , Public Health
7.
Health Res Policy Syst ; 20(1): 25, 2022 Mar 02.
Article in English | MEDLINE | ID: covidwho-1779650

ABSTRACT

BACKGROUND: In the present COVID-19 crisis, one of the greatest challenges for research funding at both the international and national level is selecting the best research topic to achieve efficiency and equity in health research and to address the knowledge gap urgently raised due to the event. Despite international recommendations, countries should consider their context-specific situation and define local research priorities. We aimed to exercise a priority-setting activity to identify the knowledge gaps and suggest research priorities in response to the COVID-19 epidemic in Iran. METHODS: First, we tried to identify the contextual knowledge gaps based on an online survey, performing key informant interviews (i.e. health professionals, policy-makers and managers) and media analysis. We also performed a literature review and considered international research priorities for COVID-19. Subsequently, we prepared a list of research questions and challenges to respond to the COVID-19 crisis in Iran using a systems approach. Then we mapped approved COVID-19 research projects in the country to research questions. Finally, we compared the identified research questions (not challenges) with the prioritized research from international organizations and then prioritized them for Iran. RESULTS: We found risk factors and epidemiological dissemination patterns of the virus and its consequences in an epidemiology domain, implementation of clinical and hygiene in a clinical management domain, genetic studies for targeting prevention and treatment in a candidate treatment and vaccine research and development (R&D) knowledge domain, examination of the manifestations of ethics in society instead of ethics in research in an ethics domain, "care, access and health system" and "public health and participation in response to public health and clinical research" as two sub-domains of a social sciences domain, and finally, no new questions in either the virology, transmission, diagnosis or animal and environmental domain. CONCLUSIONS: In the event of global health crises like COVID-19, prioritization of research questions can be done globally, but some of the research priorities are context-specific and may vary by regional needs. To better manage research resources, researchers must respond to the challenges faced in each country based on its political, economic, social and cultural characteristics, and to make evidence-informed decisions, global knowledge gaps must be customized in each country.


Subject(s)
COVID-19 , Epidemics , Epidemics/prevention & control , Health Priorities , Humans , Iran , Research , SARS-CoV-2
8.
Math Biosci Eng ; 19(5): 4911-4932, 2022 Mar 14.
Article in English | MEDLINE | ID: covidwho-1776397

ABSTRACT

In this paper, an improved COVID-19 model is given to investigate the influence of treatment and media awareness, and a non-linear saturated treatment function is introduced in the model to lay stress on the limited medical conditions. Equilibrium points and their stability are explored. Basic reproduction number is calculated, and the global stability of the equilibrium point is studied under the given conditions. An object function is introduced to explore the optimal control strategy concerning treatment and media awareness. The existence, characterization and uniqueness of optimal solution are studied. Several numerical simulations are given to verify the analysis results. Finally, discussion on treatment and media awareness is given for prevention and treatment of COVID-19.


Subject(s)
COVID-19 , Communications Media , Epidemics , Basic Reproduction Number , COVID-19/prevention & control , Epidemics/prevention & control , Humans , Quarantine
9.
Front Public Health ; 9: 665584, 2021.
Article in English | MEDLINE | ID: covidwho-1771099

ABSTRACT

Background: ODK provides software and standards that are popular solutions for off-grid electronic data collection and has substantial code overlap and interoperability with a number of related software products including CommCare, Enketo, Ona, SurveyCTO, and KoBoToolbox. These tools provide open-source options for off-grid use in public health data collection, management, analysis, and reporting. During the 2018-2020 Ebola epidemic in the North Kivu and Ituri regions of Democratic Republic of Congo, we used these tools to support the DRC Ministère de la Santé RDC and World Health Organization in their efforts to administer an experimental vaccine (VSV-Zebov-GP) as part of their strategy to control the transmission of infection. Method: New functions were developed to facilitate the use of ODK, Enketo and R in large scale data collection, aggregation, monitoring, and near-real-time analysis during clinical research in health emergencies. We present enhancements to ODK that include a built-in audit-trail, a framework and companion app for biometric registration of ISO/IEC 19794-2 fingerprint templates, enhanced performance features, better scalability for studies featuring millions of data form submissions, increased options for parallelization of research projects, and pipelines for automated management and analysis of data. We also developed novel encryption protocols for enhanced web-form security in Enketo. Results: Against the backdrop of a complex and challenging epidemic response, our enhanced platform of open tools was used to collect and manage data from more than 280,000 eligible study participants who received VSV-Zebov-GP under informed consent. These data were used to determine whether the VSV-Zebov-GP was safe and effective and to guide daily field operations. Conclusions: We present open-source developments that make electronic data management during clinical research and health emergencies more viable and robust. These developments will also enhance and expand the functionality of a diverse range of data collection platforms that are based on the ODK software and standards.


Subject(s)
Epidemics , Hemorrhagic Fever, Ebola , Data Management , Electronics , Epidemics/prevention & control , Hemorrhagic Fever, Ebola/epidemiology , Hemorrhagic Fever, Ebola/prevention & control , Humans
10.
BMC Infect Dis ; 22(1): 296, 2022 Mar 28.
Article in English | MEDLINE | ID: covidwho-1765439

ABSTRACT

BACKGROUND: The global pandemic of coronavirus disease 2019 (COVID-19) has attracted great public health efforts across the world. Few studies, however, have described the potential impact of these measures on other important infectious diseases. METHODS: The incidence of 19 major infectious diseases in Zhejiang Province was collected from the National Notifiable Infectious Disease Surveillance System from January 2017 to October 2020. The entire epidemic control phase was divided into three stages. The government deployed the first level response from 24 January to 2 March (the most rigorous measures). When the outbreak of COVID-19 was under control, the response level changed to the second level from 3 to 23 March, and then the third level response was implemented after 24 March. We compared the epidemiological characteristics of 19 major infectious diseases during different periods of the COVID-19 epidemic and previous years. RESULTS: A total of 1,814,881 cases of 19 infectious diseases were reported in Zhejiang from January 2017 to October 2020, resulting in an incidence rate of 8088.30 cases per 1,000,000 person-years. After the non-pharmaceutical intervention, the incidence of 19 infectious diseases dropped by 70.84%, from 9436.32 cases per 1,000,000 person-years to 2751.51 cases per 1,000,000 person-years, with the large decrease in the first response period of influenza. However, we observed that the daily incidence of severe fever with thrombocytopenia syndrome (SFTS) and leptospirosis increased slightly (from 1.11 cases per 1,000,000 person-years to 1.82 cases per 1,000,000 person-years for SFTS and 0.30 cases per 1,000,000 person-years to 1.24 cases per 1,000,000 person-years for leptospirosis). There was no significant difference in the distribution of epidemiological characteristic of most infectious diseases before and during the implementation of COVID-19 control measures. CONCLUSION: Our study summarizes the epidemiological characteristics of 19 infectious diseases and indicates that the rigorous control measures for COVID-19 are also effective for majority of infectious diseases.


Subject(s)
COVID-19 , Communicable Diseases , Epidemics , COVID-19/epidemiology , Communicable Diseases/epidemiology , Disease Outbreaks/prevention & control , Epidemics/prevention & control , Humans , Incidence
11.
BMC Infect Dis ; 22(1): 251, 2022 Mar 14.
Article in English | MEDLINE | ID: covidwho-1741928

ABSTRACT

BACKGROUND: Forecasting new cases, hospitalizations, and disease-induced deaths is an important part of infectious disease surveillance and helps guide health officials in implementing effective countermeasures. For disease surveillance in the US, the Centers for Disease Control and Prevention (CDC) combine more than 65 individual forecasts of these numbers in an ensemble forecast at national and state levels. A similar initiative has been launched by the European CDC (ECDC) in the second half of 2021. METHODS: We collected data on CDC and ECDC ensemble forecasts of COVID-19 fatalities, and we compare them with easily interpretable "Euler" forecasts serving as a model-free benchmark that is only based on the local rate of change of the incidence curve. The term "Euler method" is motivated by the eponymous numerical integration scheme that calculates the value of a function at a future time step based on the current rate of change. RESULTS: Our results show that simple and easily interpretable "Euler" forecasts can compete favorably with both CDC and ECDC ensemble forecasts on short-term forecasting horizons of 1 week. However, ensemble forecasts better perform on longer forecasting horizons. CONCLUSIONS: Using the current rate of change in incidences as estimates of future incidence changes is useful for epidemic forecasting on short time horizons. An advantage of the proposed method over other forecasting approaches is that it can be implemented with a very limited amount of work and without relying on additional data (e.g., data on human mobility and contact patterns) and high-performance computing systems.


Subject(s)
COVID-19 , Epidemics , Influenza, Human , COVID-19/epidemiology , Epidemics/prevention & control , Forecasting , Humans , Influenza, Human/epidemiology , Seasons
12.
Int J Environ Res Public Health ; 17(9)2020 04 30.
Article in English | MEDLINE | ID: covidwho-1725593

ABSTRACT

The COVID-19 pandemic is spreading fast globally. Vietnam's strict containment measures have significantly reduced the spread of the epidemic in the country. This was achieved through the use of emergency control measures in the epidemic areas and integration of resources from multiple sectors including health, mass media, transportation, education, public affairs, and defense. This paper reviews and shares specific measures for successful prevention and control of COVID-19 in Vietnam, which could provide useful learning for other countries.


Subject(s)
Coronavirus Infections/epidemiology , Coronavirus Infections/prevention & control , Epidemics/prevention & control , Pandemics/prevention & control , Pneumonia, Viral/epidemiology , Pneumonia, Viral/prevention & control , COVID-19 , Humans , Vietnam/epidemiology
13.
Zhonghua Yi Xue Za Zhi ; 102(7): 463-467, 2022 Feb 22.
Article in Chinese | MEDLINE | ID: covidwho-1698668

ABSTRACT

In early 2020, an outbreak of coronavirus disease 2019 (COVID-19) epidemic happened in China. In the following three months, 42 600 medical personnels and more than 9 000 public health employees were "rushed out" of their own position and onto Wuhan and other areas in Hubei Province. They helped to strengthen the treatment of severe cases and the isolation of mild cases, and actively carried out community screenings, and eventually won victory in the defense of Wuhan. During the normalization stage of prevention and control of the epidemic of COVID-19, China adopted the expanded preventive strategy by focusing on widely implement PCR testing, and integrate general and emergency departments to improve the performance of public health system. In this stage, China put out the cluster of epidemics that have occurred in several places one after another, and effectively controlled the spread of the epidemic in 2 to 3 incubation periods. In the stage of "dynamic zeroing", China emphasized the strategy of "grasping early, grasping the basics", focused on specific measures such as precise prevention in key areas. The rule of golden 24 hours was used to control the spread of the epidemic within one incubation period. During the epidemic, China continues to adopt active prevention and control strategies. This self-confidence and determination depends on adhering to the leadership of the Communist Party of China, the distinct essence of medical and health services, and significant advantages of social governance on health.


Subject(s)
COVID-19 , Epidemics , China/epidemiology , Disease Outbreaks , Epidemics/prevention & control , Humans , SARS-CoV-2
14.
Zhonghua Liu Xing Bing Xue Za Zhi ; 43(1): 1-4, 2022 Jan 10.
Article in Chinese | MEDLINE | ID: covidwho-1674892

ABSTRACT

The problems and shortcomings revealed in our response to COVID-19 epidemic have suggested us to take measures to improve the disease control and prevention system of China. For the reform and development of China's disease control and prevention institution in the new era,we need to rethink the function orientation of the disease control and prevention institution, the key and difficult points in institutional mechanism reform and the building of core competence and essential capacity of disease control and prevention system.


Subject(s)
COVID-19 , Epidemics , China/epidemiology , Epidemics/prevention & control , Health Facilities , Humans , SARS-CoV-2
15.
Sci Rep ; 12(1): 2002, 2022 02 07.
Article in English | MEDLINE | ID: covidwho-1671636

ABSTRACT

Thailand was the first country reporting the first Coronavirus disease 2019 (COVID-19) infected individual outside mainland China. Here we delineated the course of the COVID-19 outbreak together with the timeline of the control measures and public health policies employed by the Thai government during the first wave of the COVID-19 outbreak in Thailand. Based on the comprehensive epidemiological data, we reconstructed the dynamics of COVID-19 transmission in Thailand using a stochastic modeling approach. Our stochastic model incorporated the effects of individual heterogeneity in infectiousness on disease transmission, which allows us to capture relevant features of superspreading events. We found that our model could accurately capture the transmission dynamics of the first COVID-19 epidemic wave in Thailand. The model predicted that at the end of the first wave, the number of cumulative confirmed cases was 3091 (95%CI: 2782-3400). We also estimated the time-varying reproduction number (Rt) during the first epidemic wave. We found that after implementing the nationwide interventions, the Rt in Thailand decreased from the peak value of 5.67 to a value below one in less than one month, indicating that the control measures employed by the Thai government during the first COVID-19 epidemic wave were effective. Finally, the effects of transmission heterogeneity and control measures on the likelihood of outbreak extinction were also investigated.


Subject(s)
COVID-19/epidemiology , COVID-19/transmission , Epidemics/prevention & control , Models, Statistical , SARS-CoV-2 , Adult , COVID-19/prevention & control , COVID-19/virology , Communicable Disease Control/methods , Female , Humans , Male , Middle Aged , Stochastic Processes , Thailand/epidemiology , Young Adult
16.
Nat Commun ; 13(1): 411, 2022 01 20.
Article in English | MEDLINE | ID: covidwho-1641963

ABSTRACT

Prior research using electronic health records for Covid-19 vaccine safety monitoring typically focuses on specific disease groups and excludes individuals with multimorbidity, defined as ≥2 chronic conditions. We examine the potential additional risk of adverse events 28 days after the first dose of CoronaVac or Comirnaty imposed by multimorbidity. Using a territory-wide public healthcare database with population-based vaccination records in Hong Kong, we analyze a retrospective cohort of patients with chronic conditions. Thirty adverse events of special interest according to the World Health Organization are examined. In total, 883,416 patients are included and 2,807 (0.3%) develop adverse events. Results suggest vaccinated patients have lower risks of adverse events than unvaccinated individuals, multimorbidity is associated with increased risks regardless of vaccination, and the association of vaccination with adverse events is not modified by multimorbidity. To conclude, we find no evidence that multimorbidity imposes extra risks of adverse events following Covid-19 vaccination.


Subject(s)
COVID-19 Vaccines/immunology , COVID-19/immunology , SARS-CoV-2/immunology , Vaccination/statistics & numerical data , Aged , COVID-19/epidemiology , COVID-19/virology , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/adverse effects , Databases, Factual/statistics & numerical data , Epidemics/prevention & control , Female , Hong Kong/epidemiology , Humans , Male , Middle Aged , Multimorbidity , Public Health/statistics & numerical data , Retrospective Studies , Risk Factors , SARS-CoV-2/physiology , Vaccination/adverse effects
17.
Int J Health Plann Manage ; 37(3): 1205-1220, 2022 May.
Article in English | MEDLINE | ID: covidwho-1640712

ABSTRACT

Eight versions of the Protocol on Prevention and Control of Coronavirus Disease 2019 (COVID-19) (the Protocol) were issued successively by the Chinese authority to guide the local responses since the first COVID-19 case appeared in Wuhan, China. This study aimed to investigate the evolution of the overall strategy and specific measures in these Protocols, and several recommendations were provided after analysing China's response to the epidemic resurgence. As a result, we found a gradual expanding trend in case surveillance, early screening, and epidemiological investigation, as well as a progressively rigorous tendency in isolation measures and close contact management. With the Protocol's guidance, China had achieved success in several recent fights against domestic COVID-19 resurgences. The city lockdown and multiple city-wide nucleic acid tests adopted were deemed necessary in COVID-19 resurgence's battle. Besides, the large-scale distance centralised quarantine, which is, quarantine in a purpose-built isolation station away from communities where people under quarantine lived, was promoted in rural areas. China's anti-epidemic achievements provide ideas for the global battle against COVID-19.


Subject(s)
COVID-19 , Epidemics , COVID-19/prevention & control , China/epidemiology , Communicable Disease Control , Epidemics/prevention & control , Humans , Quarantine
18.
PLoS One ; 16(12): e0252972, 2021.
Article in English | MEDLINE | ID: covidwho-1598722

ABSTRACT

SARS-CoV-2 has clearly shown that efficient management of infectious diseases requires a top-down approach which must be complemented with a bottom-up response to be effective. Here we investigate a novel approach to surveillance for transboundary animal diseases using African Swine (ASF) fever as a model. We collected data both at a population level and at the local level on information-seeking behavior respectively through digital data and targeted questionnaire-based surveys to relevant stakeholders such as pig farmers and veterinary authorities. Our study shows how information-seeking behavior and resulting public attention during an epidemic, can be identified through novel data streams from digital platforms such as Wikipedia. Leveraging attention in a critical moment can be key to providing the correct information at the right moment, especially to an interested cohort of people. We also bring evidence on how field surveys aimed at local workers and veterinary authorities remain a crucial tool to assess more in-depth preparedness and awareness among front-line actors. We conclude that these two tools should be used in combination to maximize the outcome of surveillance and prevention activities for selected transboundary animal diseases such as ASF.


Subject(s)
African Swine Fever/epidemiology , Epidemics/prevention & control , Epidemiological Monitoring , Livestock/virology , Animals , Awareness , Estonia/epidemiology , Farmers , Internet , Statistics, Nonparametric , Surveys and Questionnaires , Swine
19.
PLoS One ; 16(12): e0261424, 2021.
Article in English | MEDLINE | ID: covidwho-1599330

ABSTRACT

The COVID-19 outbreak has caused two waves and spread to more than 90% of Canada's provinces since it was first reported more than a year ago. During the COVID-19 epidemic, Canadian provinces have implemented many Non-Pharmaceutical Interventions (NPIs). However, the spread of the COVID-19 epidemic continues due to the complex dynamics of human mobility. We develop a meta-population network model to study the transmission dynamics of COVID-19. The model takes into account the heterogeneity of mitigation strategies in different provinces of Canada, such as the timing of implementing NPIs, the human mobility in retail and recreation, grocery and pharmacy, parks, transit stations, workplaces, and residences due to work and recreation. To determine which activity is most closely related to the dynamics of COVID-19, we use the cross-correlation analysis to find that the positive correlation is the highest between the mobility data of parks and the weekly number of confirmed COVID-19 from February 15 to December 13, 2020. The average effective reproduction numbers in nine Canadian provinces are all greater than one during the time period, and NPIs have little impact on the dynamics of COVID-19 epidemics in Ontario and Saskatchewan. After November 20, 2020, the average infection probability in Alberta became the highest since the start of the COVID-19 epidemic in Canada. We also observe that human activities around residences do not contribute much to the spread of the COVID-19 epidemic. The simulation results indicate that social distancing and constricting human mobility is effective in mitigating COVID-19 transmission in Canada. Our findings can provide guidance for public health authorities in projecting the effectiveness of future NPIs.


Subject(s)
COVID-19/prevention & control , COVID-19/transmission , Epidemics/prevention & control , SARS-CoV-2 , Travel/statistics & numerical data , Basic Reproduction Number/statistics & numerical data , COVID-19/epidemiology , Canada/epidemiology , Humans , Incidence , Models, Statistical , Physical Distancing , Quarantine/methods
20.
Sci Rep ; 11(1): 24124, 2021 12 16.
Article in English | MEDLINE | ID: covidwho-1585805

ABSTRACT

The quantification of spreading heterogeneity in the COVID-19 epidemic is crucial as it affects the choice of efficient mitigating strategies irrespective of whether its origin is biological or social. We present a method to deduce temporal and individual variations in the basic reproduction number directly from epidemic trajectories at a community level. Using epidemic data from the 98 districts in Denmark we estimate an overdispersion factor k for COVID-19 to be about 0.11 (95% confidence interval 0.08-0.18), implying that 10 % of the infected cause between 70 % and 87 % of all infections.


Subject(s)
Algorithms , Basic Reproduction Number/statistics & numerical data , COVID-19/transmission , Models, Theoretical , SARS-CoV-2/isolation & purification , COVID-19/epidemiology , COVID-19/virology , Denmark/epidemiology , Epidemics/prevention & control , Geography , Humans , SARS-CoV-2/physiology
SELECTION OF CITATIONS
SEARCH DETAIL