scholarly journals The effect of notification window length on the epidemiological impact of COVID-19 contact tracing mobile applications

2021 ◽  
Author(s):  
Trystan Leng ◽  
Edward M Hill ◽  
Matt J Keeling ◽  
Michael J Tildesley ◽  
Robin N Thompson
Keyword(s):  
Mobile Applications ◽  
Epidemiological Model ◽  
Control Measures ◽  
Positive Test ◽  
Contact Tracing ◽  
Window Length ◽  
Trade Off ◽  
England And Wales ◽  
Before And After ◽  
Epidemiological Impact

The reduction in SARS-CoV-2 transmission from contact tracing applications (apps) depends both on the number of contacts notified and on the probability that those contacts quarantine after notification.Referring to the number of days preceding a positive test that contacts are notified as an app's notification window, we use an epidemiological model of SARS-CoV-2 transmission that captures the profile of infection to consider the trade-off between notification window length and active app-usage. We focus on 5-day and 2-day windows, the lengths used by the NHS COVID-19 app in England and Wales before and after 2nd August 2021, respectively. Short windows can be more effective at reducing transmission if they are associated with higher levels of active app usage and adherence to isolation upon notification, demonstrating the importance of understanding adherence to control measures when setting notification windows for COVID-19 apps.

scholarly journals Staff to staff transmission as a driver of healthcare worker infections with COVID-19

2020 ◽  
Author(s):  
Claire L Gordon ◽  
Jason A Trubiano ◽  
Natasha E Holmes ◽  
Kyra YL Chua ◽  
Jeff Feldman ◽  
...  
Keyword(s):  
Healthcare Workers ◽  
Control Measures ◽  
Positive Test ◽  
Contact Tracing ◽  
Positive Test Result ◽  
Tertiary Referral ◽  
Tertiary Referral Hospital ◽  
Healthcare Settings ◽  
Austin Health ◽  
Test Result

ABSTRACTObjectivesTo investigate the COVID-19 infections among staff at our institution and determine the interventions required to prevent subsequent staff infections.DesignRetrospective cohort studyParticipants and settingStaff working at a single tertiary referral hospital who returned a positive test result for SARS-CoV-2 between 25 January 2020 and 25 November 2020.Main outcome measuresSource of COVID-19 infection.ResultsOf 45 staff who returned a positive test result for SARS-CoV-2, 19 were determined to be acquired at Austin Health. Fifteen (15/19; 79% [95% CI: 54–94%]) of these were identified through contact tracing and testing following exposures to other infected staff and were presumed to be staff-staff transmission, including 10 healthcare workers (HCWs) linked to a single ward that cared for COVID-19 patients. Investigation of the outbreak identified the staff tearoom as the likely location for transmission, with subsequent reduction in HCW infections and resolution of the outbreak following implementation of enhanced control measures in tearoom facilities. No HCW contacts (0/204; 0% [95% CI: 0–2%]) developed COVID-19 infection following exposure to unrecognised patients with COVID-19.ConclusionsUnrecognised infections among staff may be a significant driver of HCW infections in healthcare settings. Control measures should be implemented to prevent acquisition from other staff as well as patient-staff transmission.

An Epidemiological Analysis of COVID-19 Confirmed Cases, Reported at National Institute of Health, Pakistan (Preprint)

2020 ◽  
Author(s):  
Ambreen Chaudhry
Keyword(s):  
Age Groups ◽  
Target Population ◽  
Control Measures ◽  
Contact Tracing ◽  
Bivariate Analysis ◽  
Travel History ◽  
Disease Epidemiology ◽  
Hygiene Practices ◽  
Multi Center Study ◽  
Epidemiological Characteristics

BACKGROUND Coronavirus disease (Covid-19) is a zoonotic disease of novel origin that posed a continuous threat to health worldwide after taking the shape of the pandemic. An understanding of disease epidemiology is supportive in timely preventive and control measures as well as contact tracing and curbing surveillance activities. OBJECTIVE The objective of our study was to determine the epidemiological characteristics of COVID-19 confirmed cases reported at the National Institute of Health Pakistan and elements of its spread in Pakistan. METHODS A retrospective record review was conducted at the National Institute of Health (NIH) Islamabad, Pakistan from January 25 to April 4, 2020. Univariate and bivariate analysis was done with 95% CI and p<0.05. RESULTS A total of 14,422 samples of suspected COVID-19 cases were received with a positivity rate of 9% (n=1348). Among all 70% (n=939) were male. The median age was 41years of age (range: 01-99Years). Among all, 19% were from 30-39 years old followed by 50-59 years old (17%). Children remained the least affected by 3% (n=35). Of the total reported cases, 55% (n=735) have reported the travel history within the last 14 days. Among these travelers’ international travelers were 23% (n=166) and domestic travelers were 77% (n=569). Travel history including both international and domestic remained significantly associated with the different age groups and Young adults remained more vulnerable to COVID-19 (P=0.03). Fever, SOB, and Cough remained the most significantly associated (P<0.05) in all age groups. CONCLUSIONS A higher incidence of COVID-19 among elderly men suggests robust quarantine measures for this target population. An escalating incidence of local transmission needs strict social distancing and hygiene practices to help flatten the curve. An extensive multi-center study is also recommended for a full understanding of disease dynamics.

scholarly journals Reduction in mobility and COVID-19 transmission

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Pierre Nouvellet ◽  
Sangeeta Bhatia ◽  
Anne Cori ◽  
Kylie E. C. Ainslie ◽  
Marc Baguelin ◽  
...  
Keyword(s):  
Predictive Ability ◽  
Control Measures ◽  
Social Distancing ◽  
Beneficial Effects ◽  
Mobility Data ◽  
Strict Control ◽  
Before And After ◽  
Proxy Measure ◽  
Lower Transmission ◽  
The Relationship

AbstractIn response to the COVID-19 pandemic, countries have sought to control SARS-CoV-2 transmission by restricting population movement through social distancing interventions, thus reducing the number of contacts. Mobility data represent an important proxy measure of social distancing, and here, we characterise the relationship between transmission and mobility for 52 countries around the world. Transmission significantly decreased with the initial reduction in mobility in 73% of the countries analysed, but we found evidence of decoupling of transmission and mobility following the relaxation of strict control measures for 80% of countries. For the majority of countries, mobility explained a substantial proportion of the variation in transmissibility (median adjusted R-squared: 48%, interquartile range - IQR - across countries [27–77%]). Where a change in the relationship occurred, predictive ability decreased after the relaxation; from a median adjusted R-squared of 74% (IQR across countries [49–91%]) pre-relaxation, to a median adjusted R-squared of 30% (IQR across countries [12–48%]) post-relaxation. In countries with a clear relationship between mobility and transmission both before and after strict control measures were relaxed, mobility was associated with lower transmission rates after control measures were relaxed indicating that the beneficial effects of ongoing social distancing behaviours were substantial.

scholarly journals Evaluating the effectiveness of measures to control the novel coronavirus disease 2019 in Jilin Province, China

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Qinglong Zhao ◽  
Yao Wang ◽  
Meng Yang ◽  
Meina Li ◽  
Zeyu Zhao ◽  
...  
Keyword(s):  
Prevention And Control ◽  
Good Control ◽  
Asymptomatic Infection ◽  
Jilin Province ◽  
Control Measures ◽  
First Case ◽  
Before And After ◽  
Novel Coronavirus ◽  
Reported Data ◽  
And Control

Abstract Background Based on differences in populations and prevention and control measures, the spread of new coronary pneumonia in different countries and regions also differs. This study aimed to calculate the transmissibility of coronavirus disease 2019 (COVID-19), and to evaluate the effectiveness of measures to control the disease in Jilin Province, China. Methods The data of reported COVID-19 cases were collected, including imported and local cases from Jilin Province as of March 14, 2019. A Susceptible–Exposed–Infectious–Asymptomatic–Recovered/Removed (SEIAR) model was developed to fit the data, and the effective reproduction number (Reff) was calculated at different stages in the province. Finally, the effectiveness of the measures was assessed. Results A total of 97 COVID-19 infections were reported in Jilin Province, among which 45 were imported infections (including one asymptomatic infection) and 52 were local infections (including three asymptomatic infections). The model fit the reported data well (R2 = 0.593, P < 0.001). The Reff of COVID-19 before and after February 1, 2020 was 1.64 and 0.05, respectively. Without the intervention taken on February 1, 2020, the predicted cases would have reached a peak of 177,011 on October 22, 2020 (284 days from the first case). The projected number of cases until the end of the outbreak (on October 9, 2021) would have been 17,129,367, with a total attack rate of 63.66%. Based on the comparison between the predicted incidence of the model and the actual incidence, the comprehensive intervention measures implemented in Jilin Province on February 1 reduced the incidence of cases by 99.99%. Therefore, according to the current measures and implementation efforts, Jilin Province can achieve good control of the virus’s spread. Conclusions COVID-19 has a moderate transmissibility in Jilin Province, China. The interventions implemented in the province had proven effective; increasing social distancing and a rapid response by the prevention and control system will help control the spread of the disease.

scholarly journals Resilience and vulnerability of maternity services in Zimbabwe: a comparative analysis of the effect of Covid-19 and lockdown control measures on maternal and perinatal outcomes, a single-centre cross-sectional study at Mpilo Central Hospital

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Clare Shakespeare ◽  
Handsome Dube ◽  
Sikhangezile Moyo ◽  
Solwayo Ngwenya
Keyword(s):  
Perinatal Outcomes ◽  
Control Measures ◽  
Central Hospital ◽  
Cross Sectional ◽  
Maternity Services ◽  
Before And After ◽  
The Mean ◽  
Significant Change ◽  
The Impact ◽  
Mpilo Central Hospital

Abstract Background On the 27th of March 2020 the Zimbabwean government declared the Covid-19 pandemic a ‘national disaster’. Travel restrictions and emergency regulations have had significant impacts on maternity services, including resource stock-outs, and closure of antenatal clinics during the lockdown period. Estimates of the indirect impact of Covid-19 on maternal and perinatal mortality was expected it to be considerable, but little data was yet available. This study aimed to examine the impact of Covid-19 and lockdown control measures on non-Covid outcomes in a government tertiary level maternity unit in Bulawayo, Zimbabwe, by comparing maternal and perinatal morbidity and mortality before, and after the lockdown was implemented. Methods This was a retrospective, observational study, using a cross-sectional design to compare routine monthly maternal and perinatal statistics three months before and after Covid-19 emergency measures were implemented at Mpilo Central Hospital. Results Between January-March and April-June 2020, the mean monthly deliveries reduced from 747.3 (SD ± 61.3) in the first quarter of 2020 to 681.0 (SD ± 17.6) during lockdown, but this was not statistically significant, p = 0.20. The Caesarean section rates fell from a mean of 29.8% (SD ± 1.7) versus 28.0% (SD ± 1.7), which was also not statistically significant, p = 0.18. During lockdown, the percentage of women delivering at Mpilo Central Hospital who were booked at the hospital fell from a mean of 41.6% (SD ± 1.1) to 35.8% (SD ± 4.3) which was statistically significant, p = 0.03. There was no significant change, however, in maternal mortality or severe maternal morbidity (such as post-partum haemorrhage (PPH), uterine rupture, and severe preeclampsia/eclampsia), stillbirth rate or special care baby unit admission. There was an increase in the mean total number of early neonatal deaths (ENND) (mean 18.7 (SD ± 2.9) versus 24.0 (SD ± 4.6), but this was not statistically significant, p = 0.32. Conclusions Overall, maternity services at Mpilo showed resilience during the lockdown period, with no significant change in maternal and perinatal adverse outcomes, with the same number of man-hours worked before and during the lockdown Maternal and perinatal outcomes should continue to be monitored to assess the impact of Covid-19 and the lockdown measures as the pandemic in Zimbabwe unfolds. Further studies would be beneficial to explore women’s experiences and understand how bookings and deliveries at local clinics changed during this time.

POLICY OF PROMOTING ALCOHOL CONSUMPTION IN TIMES OF COVID-19 LOCKDOWN IN INDIA: A MEDICAL AND CONSTITUTIONAL ANALYSIS.

2021 ◽  
pp. 21-24
Author(s):  
Neha Sharma ◽  
Ayush Anand ◽  
Shreyas Joshi ◽  
Samrat Ray
Keyword(s):  
Mobile Application ◽  
Prospective Observational Study ◽  
Social Contact ◽  
Contact Tracing ◽  
Family Welfare ◽  
Cumulative Number ◽  
Test Results ◽  
Before And After ◽  
The Given ◽  
Constitutional Analysis

BACKGROUND: India, with the declaration of COVID-19 as a pandemic, started imposing restrictions in the country th and initiated a nationwide lockdown under Section 6 of the Disaster Management Act, 2005 on 24 March 2020, followed by four phases of lockdown and then gradual unlock of the country. The rationale behind the same was to avoid social contact. Alcohol dispensing was also stopped during this time and was among the rst services to be reopened by the States. We propose in this paper that this lifting of ban on alcohol sale during the pandemic has led to a signicant increase in the number of COVID-19 cases in the country. METHODS: This is a prospective, observational study, done by collecting data from the Aargya Setu App, which is a mobile application launched by the Ministry of Health and Family Welfare on 2 April 2020 for contact tracing and elf assessment of COVID-19. The data of cumulative number of cases in 12 selected states of the country were compared before and after the lift of ban of alcohol and signicance was shown by the paired t test. RESULTS: The number of COVID-19 positive cases in the country during nationwide lockdown with simultaneous ban on alcohol sale when compared to cumulative number of cases after the lift of ban of alcohol sale during Lockdown and initial Unlock is statistically signicant (p = 0.04) CONCLUSION: We found that the decision to restart the sale of Alcohol could have been a factor for rise in number of cases in the country in the given timeframe. The decision to start the sale has also not been in accordance with the Indian Constitution and against the nation's founding ethics.

Predictors to use mobile apps for monitoring COVID-19 symptoms and contact tracing: A survey among Dutch citizens. (Preprint)

2021 ◽  
Author(s):  
Stephanie Maria Jansen-Kosterink ◽  
Marian Hurmuz ◽  
Marjolein den Ouden ◽  
Lex van Velsen
Keyword(s):  
Mobile Applications ◽  
Mobile Application ◽  
Online Survey ◽  
Reproduction Number ◽  
Mobile Apps ◽  
Contact Tracing ◽  
Snowball Sampling ◽  
Final Model ◽  
Symptom Recognition ◽  
Personal Connections

UNSTRUCTURED Background: eHealth applications have been recognized as a valuable tool to reduce COVID-19’s effective reproduction number. In this paper, we report on an online survey among Dutch citizens with the goal to identify antecedents of acceptance of a mobile application for COVID-19 symptom recognition and monitoring, and a mobile application for contact tracing. Methods: Next to the demographics, the online survey contained questions focussing on perceived health, fear of COVID-19 and intention to use. We used snowball sampling via posts on social media and personal connections. To identify antecedents of acceptance of the two mobile applications we conducted multiple linear regression analyses. Results: In total, 238 Dutch adults completed the survey. Almost 60% of the responders were female and the average age was 45.6 years (SD±17.4). For the symptom app, the final model included the predictors age, attitude towards technology and fear of COVID-19. The model had an R2 of 0.141. The final model for the tracing app included the same predictors and had an R2 of 0.156. The main reason to use both mobile applications was to control the spread of the COVID-19 virus. Concerns about privacy was mentioned as the main reason not to use the mobile applications. Conclusion: Age, attitude towards technology and fear of COVID-19 are important predictors of the acceptance of COVID-19 mobile applications for symptom recognition and monitoring and for contact tracing. These predictors should be taken into account during the development and implementation of these mobile applications to secure acceptance. Discussion: Age, attitude towards technology and fear of COVID-19 are important predictors of the acceptance of COVID-19 mobile applications for symptom recognition and monitoring and for contact tracing. These predictors should be taken into account during the development and implementation of these mobile applications to secure acceptance. Age, attitude towards technology and fear of COVID-19 are important predictors of the acceptance of COVID-19 mobile applications for symptom recognition and monitoring and for contact tracing. These predictors should be taken into account during the development and implementation of these mobile applications to secure acceptance.

scholarly journals Effect of 11 September 2001 on suicide and homicide in England and Wales

2003 ◽  
Vol 183 (3) ◽  
pp. 207-212 ◽  
Author(s):  
Emad Salib
Keyword(s):  
Suicidal Ideation ◽  
Social Cohesion ◽  
Suicide Rate ◽  
England And Wales ◽  
Female Suicide ◽  
Inverse Effect ◽  
Group Integration ◽  
Before And After ◽  
External Threat ◽  
The Impact

BackgroundThe tragic events of 11 September 2001 and televised scenes of the terrorists' homicidal and suicidal acts could have had an impact on the behaviour of some people, who harbour suicidal ideation or homicidal tendencies.AimsTo assess the effect of 11 September 2001 on the rate of suicide and homicide in England and Wales.MethodAnalysis of the number of suicides (ICD–9 codes: E950–E959), undetermined injury deaths (E980–E989) and homicides (E960–E969) in England and Wales in the 12 weeks before and after 11 September 2001 and during a similar period in the previous two years.ResultsThe number of suicides reported in the month of September 2001 was significantly lower than other months in the same year and any September of the previous 22 years in England and Wales. A suicide reduction in men, regardless of age, occurred in the week starting Tuesday 11 September 2001. A reduction in female suicide occurred during the four weeks following the attack. There was no evidence of a similar effect on homicide.ConclusionsThe tragic events of 11 September 2001 appear to have had a brief but significant inverse effect on suicide. The finding of this study supports Durkheim's theory that periods of external threat create group integration within society and lower the suicide rate through the impact on social cohesion.

scholarly journals Toward a Country-Based Prediction Model of COVID-19 Infections and Deaths Between Disease Apex and End: Evidence From Countries With Contained Numbers of COVID-19

2021 ◽  
Vol 8 ◽  
Author(s):  
Tianshu Gu ◽  
Lishi Wang ◽  
Ning Xie ◽  
Xia Meng ◽  
Zhijun Li ◽  
...  
Keyword(s):  
Real Data ◽  
Control Measures ◽  
Actual Number ◽  
The Public ◽  
The Us ◽  
Multiple Regression Models ◽  
Before And After ◽  
Using Data ◽  
High Degree ◽  
The Relationship

The complexity of COVID-19 and variations in control measures and containment efforts in different countries have caused difficulties in the prediction and modeling of the COVID-19 pandemic. We attempted to predict the scale of the latter half of the pandemic based on real data using the ratio between the early and latter halves from countries where the pandemic is largely over. We collected daily pandemic data from China, South Korea, and Switzerland and subtracted the ratio of pandemic days before and after the disease apex day of COVID-19. We obtained the ratio of pandemic data and created multiple regression models for the relationship between before and after the apex day. We then tested our models using data from the first wave of the disease from 14 countries in Europe and the US. We then tested the models using data from these countries from the entire pandemic up to March 30, 2021. Results indicate that the actual number of cases from these countries during the first wave mostly fall in the predicted ranges of liniar regression, excepting Spain and Russia. Similarly, the actual deaths in these countries mostly fall into the range of predicted data. Using the accumulated data up to the day of apex and total accumulated data up to March 30, 2021, the data of case numbers in these countries are falling into the range of predicted data, except for data from Brazil. The actual number of deaths in all the countries are at or below the predicted data. In conclusion, a linear regression model built with real data from countries or regions from early pandemics can predict pandemic scales of the countries where the pandemics occur late. Such a prediction with a high degree of accuracy provides valuable information for governments and the public.

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