scholarly journals A window of opportunity for intensifying testing and tracing efforts to prevent new COVID-19 outbreaks due to more transmissible variants

2021 ◽  
Vol 47 (7/8) ◽  
pp. 329-338
Author(s):  
Jianhong Wu ◽  
Francesca Scarabel ◽  
Zachary McCarthy ◽  
Yanyu Xiao ◽  
Nicholas H Ogden
Keyword(s):  
Public Health ◽  
Reproduction Number ◽  
Health Interventions ◽  
Contact Tracing ◽  
Window Of Opportunity ◽  
New Wave ◽  
Public Health Interventions ◽  
Contact Rates ◽  
Large Outbreak ◽  
Restrictive Measures

Background: When public health interventions are being loosened after several days of decline in the number of coronavirus disease 2019 (COVID-19) cases, it is of critical importance to identify potential strategies to ease restrictions while mitigating a new wave of more transmissible variants of concern (VOCs). We estimated the necessary enhancements to public health interventions for a partial reopening of the economy while avoiding the worst consequences of a new outbreak, associated with more transmissible VOCs. Methods: We used a transmission dynamics model to quantify conditions that combined public health interventions must meet to reopen the economy without a large outbreak. These conditions are those that maintain the control reproduction number below unity, while accounting for an increase in transmissibility due to VOC. Results: We identified combinations of the proportion of individuals exposed to the virus who are traced and quarantined before becoming infectious, the proportion of symptomatic individuals confirmed and isolated, and individual daily contact rates needed to ensure the control reproduction number remains below unity. Conclusion: Our analysis indicates that the success of restrictive measures including lockdown and stay-at-home orders, as reflected by a reduction in number of cases, provides a narrow window of opportunity to intensify case detection and contact tracing efforts to prevent a new wave associated with circulation of more transmissible VOCs.

scholarly journals Effectiveness of non-pharmaceutical public health interventions against COVID-19: A systematic review and meta-analysis

PLoS ONE ◽  
2021 ◽  
Vol 16 (11) ◽  
pp. e0260371
Author(s):  
Shabnam Iezadi ◽  
Kamal Gholipour ◽  
Saber Azami-Aghdash ◽  
Akbar Ghiasi ◽  
Aziz Rezapour ◽  
...  
Keyword(s):  
Public Health ◽  
Systematic Review ◽  
Growth Rate ◽  
Reproduction Number ◽  
Meta Analysis ◽  
Health Interventions ◽  
Contact Tracing ◽  
Public Health Interventions ◽  
Icu Admission ◽  
Daily Changes

Non-Pharmaceutical Public Health Interventions (NPHIs) have been used by different countries to control the spread of the COVID-19. Despite available evidence regarding the effectiveness of NPHSs, there is still no consensus about how policymakers can trust these results. Studies on the effectiveness of NPHSs are single studies conducted in specific communities. Therefore, they cannot individually prove if these interventions have been effective in reducing the spread of the infection and its adverse health outcomes. In this systematic review, we aimed to examine the effects of NPHIs on the COVID-19 case growth rate, death growth rate, Intensive Care Unit (ICU) admission, and reproduction number in countries, where NPHIs have been implemented. We searched relevant electronic databases, including Medline (via PubMed), Scopus, CINAHL, Web of Science, etc. from late December 2019 to February 1, 2021. The key terms were primarily drawn from Medical Subject Heading (MeSh and Emtree), literature review, and opinions of experts. Peer-reviewed quasi-experimental studies were included in the review. The PROSPERO registration number is CRD42020186855. Interventions were NPHIs categorized as lockdown, stay-at-home orders, social distancing, and other interventions (mask-wearing, contact tracing, and school closure). We used PRISMA 2020 guidance for abstracting the data and used Cochrane Effective Practice and Organization of Practice (EPOC) Risk of Bias Tool for quality appraisal of the studies. Hartung-Knapp-Sidik-Jonkman random-effects model was performed. Main outcomes included COVID-19 case growth rate (percentage daily changes), COVID-19 mortality growth rate (percentage daily changes), COVID-19 ICU admission (percentage daily changes), and COVID-19 reproduction number changes. Our search strategies in major databases yielded 12,523 results, which decreased to 7,540 articles after eliminating duplicates. Finally, 35 articles qualified to be included in the systematic review among which 23 studies were included in the meta-analysis. Although studies were from both low-income and high-income countries, the majority of them were from the United States (13 studies) and China (five studies). Results of the meta-analysis showed that adoption of NPHIs has resulted in a 4.68% (95% CI, -6.94 to -2.78) decrease in daily case growth rates, 4.8% (95 CI, -8.34 to -1.40) decrease in daily death growth rates, 1.90 (95% CI, -2.23 to -1.58) decrease in the COVID-19 reproduction number, and 16.5% (95% CI, -19.68 to -13.32) decrease in COVID-19 daily ICU admission. A few studies showed that, early enforcement of lockdown, when the incidence rate is not high, contributed to a shorter duration of lockdown and a lower increase of the case growth rate in the post-lockdown era. The majority of NPHIs had positive effects on restraining the COVID-19 spread. With the problems that remain regarding universal access to vaccines and their effectiveness and considering the drastic impact of the nationwide lockdown and other harsh restrictions on the economy and people’s life, such interventions should be mitigated by adopting other NPHIs such as mass mask-wearing, patient/suspected case isolation strategies, and contact tracing. Studies need to address the impact of NPHIs on the population’s other health problems than COVID-19.

scholarly journals Evolution of disease transmission rate during the course of SARS-COV-2: Patterns and determinants

2020 ◽  
Author(s):  
Jie Zhu ◽  
Blanca Gallego
Keyword(s):  
Public Health ◽  
Disease Transmission ◽  
Reproduction Number ◽  
Transmission Rate ◽  
Region Of Interest ◽  
Health Interventions ◽  
Transmission Model ◽  
Public Health Interventions ◽  
Containment Measures ◽  
The Impact

Abstract To date, many studies have argued the potential impact of public health interventions on flattening the epidemic curve of SARS-CoV-2. Most of them have focused on simulating the impact of interventions in a region of interest by manipulating contact patterns and key transmission parameters to reflect different scenarios. Our study looks into the evolution of the daily effective reproduction number during the epidemic via a stochastic transmission model. We found this measure (although model-dependent) provides an early signal of the efficacy of containment measures. This epidemiological parameter when updated in real-time can also provide better predictions of future outbreaks. Our results found a substantial variation in the effect of public health interventions on the dynamic of SARS-CoV-2 transmission over time and across countries, that could not be explained solely by the timing and number of the adopted interventions. This suggests that further knowledge about the idiosyncrasy of their implementation and effectiveness is required. Although sustained containment measures have successfully lowered growth in disease transmission, more than half of the 101 studied countries failed to maintain the effective reproduction number close to or below 1. This resulted in continued growth in reported cases. Finally, we were able to predict with reasonable accuracy which countries would experience outbreaks in the next 30 days.

scholarly journals Mandating the Use of Proximity Tracking Apps During Coronavirus Disease 2019: Ethical Justifications

2020 ◽  
Vol 7 ◽  
Author(s):  
Riya Dave ◽  
Rashmi Gupta
Keyword(s):  
Public Health ◽  
Large Degree ◽  
Health Interventions ◽  
World Health ◽  
Contact Tracing ◽  
Public Health Interventions ◽  
Societal Factors ◽  
Digital World ◽  
Health Organization ◽  
Mandatory Policy

The rise of the coronavirus disease 2019 (COVID-19) in a digital world has expectedly called upon technologies, such as wearables and mobile devices, to work in conjunction with public health interventions to tackle the pandemic. One significant example of this integration is the deployment of proximity tracking apps on smartphones to enhance traditional contact tracing methods. Many countries have adopted proximity tracking apps; however, there is a large degree of global differentiation in the voluntariness of the apps. Further, the concept of a mandatory policy—forcing individuals to use the apps—has been met with ethical concerns (e.g., privacy and liberty). While ethical considerations surrounding deployment have been put forth, such as by the World Health Organization, ethical justifications for a mandatory policy are lacking. Here, we use the Faden–Shebaya framework, which was formed to justify public health interventions, to determine if the compulsory use of proximity tracking apps is ethically appropriate. We show that while theoretically justified, due to the current state of proximity tracking applications and societal factors, it is difficult to defend a mandatory policy in practice.

scholarly journals Does the data tell the true story? A modelling assessment of early COVID-19 pandemic suppression and mitigation strategies in Ghana

PLoS ONE ◽  
2021 ◽  
Vol 16 (10) ◽  
pp. e0258164
Author(s):  
Nana Kena Frempong ◽  
Theophilus Acheampong ◽  
Ofosuhene O. Apenteng ◽  
Emmanuel Nakua ◽  
John H. Amuasi
Keyword(s):  
Public Health ◽  
Reproduction Number ◽  
Severe Disease ◽  
Mitigation Strategies ◽  
Health Interventions ◽  
New Wave ◽  
Systematic Testing ◽  
True Incidence ◽  
True Story ◽  
Health Measures

This paper uses publicly available data and various statistical models to estimate the basic reproduction number (R0) and other disease parameters for Ghana’s early COVID-19 pandemic outbreak. We also test the effectiveness of government imposition of public health measures to reduce the risk of transmission and impact of the pandemic, especially in the early phase. R0 is estimated from the statistical model as 3.21 using a 0.147 estimated growth rate [95% C.I.: 0.137–0.157] and a 15-day time to recovery after COVID-19 infection. This estimate of the initial R0 is consistent with others reported in the literature from other parts of Africa, China and Europe. Our results also indicate that COVID-19 transmission reduced consistently in Ghana after the imposition of public health interventions—such as border restrictions, intra-city movement, quarantine and isolation—during the first phase of the pandemic from March to May 2020. However, the time-dependent reproduction number (Rt) beyond mid-May 2020 does not represent the true situation, given that there was not a consistent testing regime in place. This is also confirmed by our Jack-knife bootstrap estimates which show that the positivity rate over-estimates the true incidence rate from mid-May 2020. Given concerns about virus mutations, delays in vaccination and a possible new wave of the pandemic, there is a need for systematic testing of a representative sample of the population to monitor the reproduction number. There is also an urgent need to increase the availability of testing for the general population to enable early detection, isolation and treatment of infected individuals to reduce progression to severe disease and mortality.

scholarly journals Effective public health measures to mitigate the spread of COVID-19: a systematic review

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Imen Ayouni ◽  
Jihen Maatoug ◽  
Wafa Dhouib ◽  
Nawel Zammit ◽  
Sihem Ben Fredj ◽  
...  
Keyword(s):  
Public Health ◽  
Systematic Review ◽  
Health Workers ◽  
Experimental Studies ◽  
Health Interventions ◽  
Contact Tracing ◽  
Public Health Interventions ◽  
Health Measures ◽  
Mesh Terms ◽  
Novel Coronavirus

Abstract Background In December 2019, a novel coronavirus (2019-nCoV) was recognized in Wuhan, China. It was characterised by rapid spread causing a pandemic. Multiple public health interventions have been implemented worldwide to decrease the transmission of the 2019 novel coronavirus disease (COVID-19). The objective of this systematic review is to evaluate the implemented public health interventions to control the spread of the outbreak of COVID-19. Methods: We systematically searched PubMed, Science Direct and MedRxiv for relevant articles published in English up to March 16, 2021. We included quasi experimental studies, clinical trials, cohort studies, longitudinal studies, case-control studies and interrupted time series. We included the studies that investigated the effect of the implemented public health measures to prevent and control the outbreak of 2019 novel coronavirus disease (COVID-19). Results The database search using the predefined combinations of Mesh terms found 13,497 studies of which 3595 in PubMed, 7393 in Science Direct 2509 preprints in MedRxiv. After removal of the duplicates and the critical reading only 18 articles were included in this systematic review and processed for data extraction. Conclusions Public health interventions and non-pharmaceutical measurements were effective in decreasing the transmission of COVID-19. The included studies showed that travel restrictions, borders measures, quarantine of travellers arriving from affected countries, city lockdown, restrictions of mass gathering, isolation and quarantine of confirmed cases and close contacts, social distancing measures, compulsory mask wearing, contact tracing and testing, school closures and personal protective equipment use among health workers were effective in mitigating the spread of COVID-19.

scholarly journals Modelling digital and manual contact tracing for COVID-19 Are low uptakes and missed contacts deal-breakers?

2021 ◽  
Author(s):  
Andrei Rusu ◽  
Katayoun Farrahi ◽  
Rémi Emonet
Keyword(s):  
Public Health ◽  
Mean Field ◽  
Epidemiological Model ◽  
Health Interventions ◽  
Contact Tracing ◽  
Public Health Interventions ◽  
Fair Proportion ◽  
Usage Patterns ◽  
The Right ◽  
The Impact

ABSTRACTComprehensive testing schemes, followed by adequate contact tracing and isolation, represent the best public health interventions we can employ to reduce the impact of an ongoing epidemic when no or limited vaccines are available and the implications of a full lockdown are to be avoided. However, the process of tracing can prove feckless for highly-contagious viruses such as SARS-Cov-2. The interview-based approaches often miss contacts and involve significant delays, while digital solutions can suffer from insufficient adoption rates or inadequate usage patterns. Here we present a novel way of modelling different contact tracing strategies using a generalized multi-site mean-field model, which can naturally assess the impact of both manual and digital approaches. Our methodology can readily be applied to any compartmental formulation, thus enabling the study of several complex pathogens. We use this technique to simulate a new epidemiological model, SEIR-T, and show that, given the right conditions, tracing in a COVID-19 epidemic can be effective even when digital uptakes are sub-optimal or interviewers miss a fair proportion of the contacts.

scholarly journals Transmission dynamics of COVID-19 in Ghana and the impact of public health interventions

2021 ◽  
Author(s):  
Sylvia K. Ofori ◽  
Jessica S. Schwind ◽  
Kelly L. Sullivan ◽  
Benjamin J Cowling ◽  
Gerardo Chowell ◽  
...  
Keyword(s):  
Public Health ◽  
Reproduction Number ◽  
National Level ◽  
Health Interventions ◽  
Time Varying ◽  
Public Health Interventions ◽  
The Public ◽  
Case Count ◽  
Lower Case ◽  
The Impact

The study characterized the transmission of COVID-19 in Ghana by estimating the time-varying reproduction number (Rt) and exploring the effect of various public health interventions at the national and regional levels. The median Rt for Ghana and six out of sixteen regions dropped from greater than 1 in March 2020 to less than 1 in September but increased above 1 in January 2021. The relaxation of movement restrictions and religious gatherings were not associated with increased Rt in the regions with lower case burdens. However, Rt increased in most regions after schools were reopened in January 2021. In a regression analysis, we estimated that the per-capita cumulative case count increased with population size. Findings indicated the public health interventions reduced the Rt at the national level while at the regional levels, the Rt fluctuated, and the extent of fluctuation varied across regions.

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