scholarly journals On Identifying and Mitigating Bias in the Estimation of the COVID-19 Case Fatality Rate

2020 ◽  
Author(s):  
Anastasios Nikolas Angelopoulos ◽  
Reese Pathak ◽  
Rohit Varma ◽  
Michael I. Jordan
Keyword(s):  
Patient Outcomes ◽  
Case Fatality Rate ◽  
Time Lag ◽  
Case Fatality ◽  
Primary Source ◽  
Time Lags ◽  
Medical Resource ◽  
Potential Significance ◽  
Source Of Information ◽  
Relative Case

AbstractThe relative case fatality rates (CFRs) between groups and countries are key measures of relative risk that guide policy decisions regarding scarce medical resource allocation during the ongoing COVID-19 pandemic. In the middle of an active outbreak when surveillance data is the primary source of information, estimating these quantities involves compensating for competing biases in time series of deaths, cases, and recoveries. These include time- and severity-dependent reporting of cases as well as time lags in observed patient outcomes. In the context of COVID-19 CFR estimation, we survey such biases and their potential significance. Further, we analyze theoretically the effect of certain biases, like preferential reporting of fatal cases, on naive estimators of CFR. We provide a partially corrected estimator of these naive estimates that accounts for time lag and imperfect reporting of deaths and recoveries. We show that collection of randomized data by testing the contacts of infectious individuals regardless of the presence of symptoms would mitigate bias by limiting the covariance between diagnosis and death. Our analysis is supplemented by theoretical and numerical results and a simple and fast open-source codebase.1

scholarly journals The role of age distribution, time lag between reporting and death and healthcare system capacity on case fatality estimates of COVID-19

2020 ◽  
Author(s):  
Patrizio Vanella ◽  
Christian Wiessner ◽  
Anja Holz ◽  
Gerard Krause ◽  
Annika Moehl ◽  
...  
Keyword(s):  
Time Lag ◽  
Age Distribution ◽  
Case Fatality ◽  
System Capacity ◽  
Time Lags ◽  
Cross Country ◽  
The Difference ◽  
Case Fatality Risk ◽  
The Impact

European countries report large differences in coronavirus disease (COVID-19) case fatality risk (CFR). CFR estimates depend on demographic characteristics of the cases, time lags between reporting of infections and deaths and infrastructural characteristics, such as healthcare and surveillance capacities. We discuss the impact of these factors on the CFR estimates for Germany, Italy, France, and Spain for the COVID-19 pandemic from early March to mid-April, 2020. We found that, first, a large proportion of the difference in CFRs can be attributed to different age structures of the cases. Second, lags of 5-10 days between day of case report and death should be used, since these provide the most constant estimates. Third, for France, Italy, and Spain, intensive care beds occupied by COVID-19 patients were positively associated with fatality risks of hospitalized cases. Our results highlight that cross-country comparisons of crude CFR estimates can be misleading and should be avoided.

scholarly journals COVID-19 cases and deaths after implementation of prevention strategies, Saudi Arabia, 2 March to 5 July 2020

2021 ◽  
Author(s):  
Nargis B. Javed ◽  
Mohammed Zuber ◽  
Saba Amin ◽  
Bussma A. Bugis ◽  
Mohammed Almohaithef
Keyword(s):  
Saudi Arabia ◽  
Case Fatality Rate ◽  
Phase 1 ◽  
Time Lag ◽  
Case Fatality ◽  
Point Prevalence ◽  
Eastern Region ◽  
Fatality Rate ◽  
Prevention Strategies ◽  
Overall Mortality

Background: To prevent the spread of coronavirus disease 2019 (COVID-19), the Saudi Arabian government introduced a number of measures in different phases (e.g. social distancing, curfew and lockdown). Aims: This study describes the distribution of COVID-19 in Saudi Arabia during different phases of prevention strategies and assesses their effect on controlling the spread of the disease. Methods: This cross-sectional study used COVID-19 data for 2 March–5 July 2020 from the Ministry of Health website. The period was divided into five phases based on prevention strategies implemented to control the infection. The incidence rate, point prevalence, case fatality rate, overall mortality rate and recovered rate for COVID-19 infection were assessed at the national, regional and city levels. Results: At the end of phase 5 on 5 July 2020, the nationwide incidence of COVID-19 was 11%, total recovered rate 70%, case fatality rate 0.9% and adjusted case fatality rate 1.4% (adjusted for time lag for mortality). The COVID-19 point prevalence increased from phase 1 (2.1/100 000 population) to phase 5 (178.2/100 000 population). A high recovered rate (68.7%) was seen in phase 4 accompanied with lower overall mortality and incidence in phase 5. The eastern region of Saudi Arabia had the highest point prevalence of COVID-19 infection (450.5 per 100 000 population), while Jeddah and Mecca had the highest overall mortality.

scholarly journals Demystifying the varying case fatality rates (CFR) of COVID-19 in India: Lessons learned and future directions

2020 ◽  
Vol 14 (10) ◽  
pp. 1128-1135
Author(s):  
Edwin Sam Asirvatham ◽  
Jeyaseelan Lakshmanan ◽  
Charishma Jones Sarman ◽  
Melvin Joy
Keyword(s):  
Urban Population ◽  
Case Fatality Rate ◽  
Time Lag ◽  
Case Fatality ◽  
State Level ◽  
Lessons Learned ◽  
Cumulative Number ◽  
Fatality Rate ◽  
Targeted Interventions ◽  
Socio Demographic Factors

Introduction: At the end of the second week of June 2020, the SARS-CoV-2 responsible for COVID-19 infected above 7.5 million people and killed over 400,000 worldwide. Estimation of case fatality rate (CFR) and determining the associated factors are critical for developing targeted interventions. Methodology: The state-level adjusted case fatality rate (aCFR) was estimated by dividing the cumulative number of deaths on a given day by the cumulative number confirmed cases 8 days before, which is the average time-lag between diagnosis and death. We conducted fractional regression analysis to determine the predictors of aCFR. Results: As of 13 June 2020, India reported 225 COVID-19 cases per million population (95% CI:224-226); 6.48 deaths per million population (95% CI:6.34-6.61) and an aCFR of 3.88% (95% CI:3.81-3.97) with wide variation between states. High proportion of urban population and population above 60 years were significantly associated with increased aCFR (p=0.08, p=0.05), whereas, high literacy rate and high proportion of women were associated with reduced aCFR (p<0.001, p=0.03). The higher number of cases per million population (p=0.001), prevalence of diabetes and hypertension (p=0.012), cardiovascular diseases (p=0.05), and any cancer (p<0.001) were significantly associated with increased aCFR. The performance of state health systems and proportion of public health expenditure were not associated with aCFR. Conclusions: Socio-demographic factors and burden of non-communicable diseases (NCDs) were found to be the predictors of aCFR. Focused strategies that would ensure early identification, testing and effective targeting of non-literate, elderly, urban population and people with comorbidities are critical to control the pandemic and fatalities.

scholarly journals Case fatality rates for COVID-19 are higher than case fatality rates for motor vehicle accidents for individuals over 40 years of age

2021 ◽  
Author(s):  
Arjun Puranik ◽  
Michiel J.M. Niesen ◽  
Emily Lindemer ◽  
Patrick Lenehan ◽  
Tudor Cristea-Platon ◽  
...  
Keyword(s):  
Case Fatality Rate ◽  
Motor Vehicle ◽  
Motor Vehicle Accident ◽  
Case Fatality ◽  
Motor Vehicle Accidents ◽  
Age Group ◽  
Fatality Rate ◽  
Vehicle Accidents ◽  
Vehicle Accident ◽  
Relative Case

The death toll of the COVID-19 pandemic has been unprecedented, due to both the high number of SARS-CoV-2 infections and the seriousness of the disease resulting from these infections. Here, we present mortality rates and case fatality rates for COVID-19 over the past year compared with other historic leading causes of death in the United States. Among the risk categories considered, COVID-19 is the third leading cause of death for individuals 40 years old and over, with an overall annual mortality rate of 325 deaths per 100K individuals, behind only cancer (385 deaths per 100K individuals) and heart disease (412 deaths per 100K individuals). In addition, for individuals 40 years old and over, the case fatality rate for COVID-19 is greater than the case fatality rate for motor vehicle accidents. In particular, for the age group 40-49, the relative case fatality rate of COVID-19 is 1.5 fold (95% CI: [1.3, 1.7]) that of a motor vehicle accident, demonstrating that SARS-CoV-2 infection may be significantly more dangerous than a car crash for this age group. For older adults, COVID-19 is even more dangerous, and the relative case fatality rate of COVID-19 is 29.4 fold (95% CI: [23.2, 35.7]) that of a motor vehicle accident for individuals over 80 years old. On the other hand, motor vehicle accidents have a 4.5 fold (95% CI: [3.9, 5.1]) greater relative case fatality rate compared to COVID-19 for the age group of 20-29 years. These results highlight the severity of the COVID-19 pandemic especially for adults above 40 years of age and underscore the need for large-scale preventative measures to mitigate risks for these populations. Given that FDA-authorized COVID-19 vaccines have now been validated by multiple studies for their outstanding real-world effectiveness and safety, vaccination of all individuals who are over 40 years of age is one of the most pressing public health priorities of our time.

scholarly journals The Role of Age Distribution, Time Lag Between Reporting and Death and Healthcare System Capacity in Case Fatality Estimates of COVID-19

2020 ◽  
Author(s):  
Patrizio Vanella ◽  
Christian Wiessner ◽  
Anja Holz ◽  
Gérard Krause ◽  
Annika Möhl ◽  
...  
Keyword(s):  
Intensive Care ◽  
Time Lag ◽  
Age Distribution ◽  
Case Fatality ◽  
European Countries ◽  
System Capacity ◽  
Optimal Time ◽  
Time Lags ◽  
Bed Capacity ◽  
The Impact

Abstract Background: European countries report large differences in coronavirus disease (COVID-19) case fatality risk (CFR). CFR estimates depend on demographic characteristics of the cases, time lags between reporting of infections and deaths and infrastructural characteristics, such as healthcare and surveillance capacities. Methods: We used publicly available data from official reports of the national health authorities of Germany, Italy, France, and Spain on COVID-19. These include age-specific numbers of cases and deaths for different dates, which we used to compute age-standardized CFR ratios using a standard European population for standardization. Moreover, we investigated the impact of different potential time lags on the estimation of the CFR using data published by the European Centre for Disease Prevention and Control (ECDC). Finally, we described the association between case fatality and the intensive care bed capacity.Results: We found that age-standardized CFR estimates increased from the beginning of March to mid-May 2020 in all included European countries. In Germany, CFRs are lower than in other countries. However, the differences are much larger when comparing the crude risks rather than the age-adjusted risks. Thus, the different age distribution of the cases account for a major proportion of the reported differences. Case fatality estimates using time lags of 1-10 days converged in all countries over time, however, there is no optimal time lag to assess the CFR during the pandemic. Time lags that provided the most constant estimates and approach best the observed CFR after the pandemic ranged from 5-10 days in different countries and at different time points during the pandemic. For the association between intensive care bed capacity and fatality we found that days with a high need for intensive care beds were positively correlated with daily hospitalization fatality in France, Italy, and Spain, but not in Germany. Conclusions: Our results highlight that cross-country comparisons of crude CFR estimates can be misleading and should be avoided. However, to adjust for potential sources of bias more disaggregated data and information on surveillance and health care capacities are needed. Filling these gaps and harmonizing data across European countries will facilitate further analysis.

Impact of hydroxychloroquin/azithromycin protocol on COVID-19 case-fatality rate reduction in Algeria. (Preprint)

2020 ◽  
Author(s):  
Ahmed Youssef Kada
Keyword(s):  
Case Fatality Rate ◽  
Doubling Time ◽  
Case Fatality ◽  
World Health ◽  
Fatality Rate ◽  
Therapeutic Protocol ◽  
First Case ◽  
The World ◽  
The Impact ◽  
At Home

BACKGROUND Covid-19 is an emerging infectious disease like viral zoonosis caused by new coronavirus SARS CoV 2. On December 31, 2019, Wuhan Municipal Health Commission in Hubei province (China) reported cases of pneumonia, the origin of which is a new coronavirus. Rapidly extendable around the world, the World Health Organization (WHO) declares it pandemic on March 11, 2020. This pandemic reaches Algeria on February 25, 2020, date on which the Algerian minister of health, announced the first case of Covid-19, a foreign citizen. From March 1, a cluster is formed in Blida and becomes the epicentre of the coronavirus epidemic in Algeria, its total quarantine is established on March 24, 2020, it will be smoothly alleviated on April 24. A therapeutic protocol based on hydroxychloroquine and azithromycin was put in place on March 23, for complicated cases, it was extended to all the cases confirmed on April 06. OBJECTIVE This study aimed to demonstrate the effectiveness of hydroxychloroquin/azithromycin protocol in Algeria, in particular after its extension to all patients diagnosed COVID-19 positive on RT-PCR test. We were able to illustrate this fact graphically, but not to prove it statistically because the design of our study, indeed in the 7 days which followed generalization of therapeutic protocol, case fatality rate decrease and doubling time increase, thus confirming the impact of wide and early prescription of hydroxychloroquin/azithromycin protocol. METHODS We have analyzed the data collected from press releases and follow-ups published daily by the Ministry of Health, we have studied the possible correlations of these data with certain events or decisions having a possible impact on their development, such as confinement at home and its reduction, the prescription of hydroxychloroquine/azithromycin combination for serious patients and its extension to all positive COVID subjects. Results are presented in graphics, the data collection was closed on 31/05/2020. RESULTS Covid-19 pandemic spreads from February 25, 2020, when a foreign citizen is tested positive, on March 1 a cluster is formed in the city of Blida where sixteen members of the same family are infected during a wedding party. Wilaya of Blida becomes the epicentre of coronavirus epidemic in Algeria and lockdown measures taken, while the number of national cases diagnosed begins to increases In any event, the association of early containment measures combined with a generalized initial treatment for all positive cases, whatever their degree of severity, will have contributed to a reduction in the fatality rate of COVID 19 and a slowing down of its doubling time. CONCLUSIONS In Algeria, the rapid combination of rigorous containment measure at home and early generalized treatment with hydroxychloroquin have demonstrated their effectiveness in terms of morbidity and mortality, the classic measures of social distancing and hygiene will make it possible to perpetuate these results by reducing viral transmission, the only unknown, the reopening procedure which can only be started after being surrounded by precautions aimed at ensuring the understanding of the population. CLINICALTRIAL Algeria, Covid-19, pandemic, hydroxychloroquin, azithromycin, case fatality rate

scholarly journals Author Correction: Calcium channel blocker amlodipine besylate therapy is associated with reduced case fatality rate of COVID-19 patients with hypertension

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Lei-Ke Zhang ◽  
Yuan Sun ◽  
Haolong Zeng ◽  
Qingxing Wang ◽  
Xiaming Jiang ◽  
...  
Keyword(s):  
Calcium Channel ◽  
Calcium Channel Blocker ◽  
Case Fatality Rate ◽  
Channel Blocker ◽  
Case Fatality ◽  
Fatality Rate ◽  
Amlodipine Besylate

A Correction to this paper has been published: https://doi.org/10.1038/s41421-021-00267-0

scholarly journals Early determination of case fatality rate of COVID-19 pandemic during the ongoing Yemeni armed conflict

2021 ◽  
pp. 1-15
Author(s):  
Abdulla Salem Bin Ghouth ◽  
Ali Ahmed Al-Waleedi ◽  
Marhami Fahriani ◽  
Firzan Nainu ◽  
Harapan Harapan
Keyword(s):  
Young Adults ◽  
Intensive Care ◽  
Armed Conflict ◽  
Case Fatality Rate ◽  
Preventive Measures ◽  
Case Fatality ◽  
Fatality Rate ◽  
Mechanical Ventilators ◽  
Poor Outcomes

Abstract Objectives: To determine the case-fatality rate (CFR) of coronavirus disease 2019 (COVID-19) and its associated determinants in order to understand the true magnitude of the problem during ongoing conflict in Yemen. Methods: The CFR among confirmed COVID-19 cases in Yemen was calculated. The data was retrieved from national COVID-19 surveillance between April 10, when the first COVID-19 case reported, and May 31, 2020. Results: A total of 419 confirmed COVID-19 cases were reported. There were 14.1% and 5.7% of cases who required intensive care and mechanical ventilators, respectively. Out of total cases, 95 deaths were reported, giving CFR of 22.6% which is much higher compared to other countries. CFR was significantly higher among elderly compared to young adults and varied between governorates. Mortality was associated with preexisting hypertension (OR: 2.30; 95%CI: 1.58, 3.54) and diabetes (OR: 1.68; 95%CI: 1.08, 2.61). Conclusions: Elderly and those with comorbidities, in particular hypertension and diabetes, have higher risk for poor outcomes and therefore should receive more attention in the clinical setting. Preventive measures should also be prioritized to protect those groups in order to reduce the severe cases and deaths-associated COVID-19 in armed-conflict.

scholarly journals In Vitro Model of Mycobacterial Growth Arrest Using Nitric Oxide with Limited Air

2008 ◽  
Vol 53 (1) ◽  
pp. 157-161 ◽  
Author(s):  
Syed Hussain ◽  
Muhammad Malik ◽  
Lanbo Shi ◽  
Maria Laura Gennaro ◽  
Karl Drlica
Keyword(s):  
Nitric Oxide ◽  
In Vitro Model ◽  
Transition Period ◽  
Time Lag ◽  
Growth Arrest ◽  
Ring Structure ◽  
Time Lags ◽  
Vitro Model ◽  
Mycobacterial Growth

ABSTRACT An in vitro model of mycobacterial growth arrest was developed using Mycobacterium bovis BCG. When an exponentially growing culture was transferred to an evacuated tube, growth continued; treatment with a source of nitric oxide (diethylenetriamine-nitric oxide adduct [DETA-NO] at 50 μM) halted growth immediately, and aeration restored growth. When the period of growth arrest exceeded 4 h, a time lag occurred before aeration could restore growth. The lag time was maximal (24 h) after 16 h of growth arrest. These time lags indicated that one transition period was required for cells to achieve full arrest of growth and another for them to recover fully from growth arrest. DETA-NO-induced growth arrest failed to protect from the lethal effects of anaerobic shock, which caused rapid lysis of both growing and growth-arrested cells. While growth arrest had little effect on the lethal action of rifampin, it eliminated isoniazid lethality. Growth arrest reduced but did not eliminate fluoroquinolone lethality. Two fluoroquinolones, moxifloxacin and gatifloxacin, were equally lethal to exponentially growing cells, but moxifloxacin was more active during growth arrest. This difference is attributed to the fluoroquinolone C-7 ring structure, the only difference between the compounds. Collectively these data characterize a new system for halting mycobacterial growth that may be useful for evaluating new antituberculosis agents.

Sign in / Sign up

Export Citation Format

Share Document