scholarly journals Estimation of exponential growth rate and basic reproduction number of the coronavirus disease 2019 (COVID-19) in Africa

2020 ◽  
Author(s):  
Salihu S Musa ◽  
Shi Zhao ◽  
Maggie H Wang ◽  
Abdurrazaq G Habib ◽  
Umar T Mustapha ◽  
...  
Keyword(s):  
Growth Rate ◽  
Basic Reproduction Number ◽  
Exponential Growth ◽  
Initial Phase ◽  
Reproduction Number ◽  
Initial Growth ◽  
Exponential Growth Rate ◽  
Preparedness Planning ◽  
First Case ◽  
Exponential Growth Model

Abstract Background Since the first case of coronavirus disease 2019 (COVID-19) was detected on February 14, 2020, the cumulative confirmations reached 15207 including 831 deaths by April 13, 2020. Methods We analyzed the initial phase of the epidemic of COVID-19 in Africa between 1 March and 13 April 2020, by using the simple exponential growth model.Results We estimated the exponential growth rate as 0.22 per day (95%CI: 0.20 – 0.24), and the basic reproduction number, R0, to be 2.37 (95%CI: 2.22-2.51) based on the assumption that the exponential growth starting from 1 March 2020.Conclusion The initial growth of COVID-19 cases in Africa was rapid and showed large variations across countries. Our estimates should be useful in preparedness planning. Trial registration: NA

scholarly journals Estimation of exponential growth rate and basic reproduction number of the coronavirus disease 2019 (COVID-19) in Africa

2020 ◽  
Author(s):  
Salihu S Musa ◽  
Shi Zhao ◽  
Maggie H Wang ◽  
Abdurrazaq G Habib ◽  
Umar T Mustapha ◽  
...  
Keyword(s):  
Growth Rate ◽  
Basic Reproduction Number ◽  
Exponential Growth ◽  
Initial Phase ◽  
Reproduction Number ◽  
Exponential Growth Rate ◽  
Preparedness Planning ◽  
First Case ◽  
Exponential Growth Model ◽  
The Basic Reproduction Number

Abstract Since the first case of coronavirus disease 2019 (COVID-19) was detected on February 14, 2020, the cumulative confirmations reached 834 including 17 deaths by March 19, 2020. We analyzed the initial phase of the epidemic of COVID-19 in Africa between 1 March and 19 March 2020, by using the simple exponential growth model. We estimated the exponential growth rate as 0.22 per day (95%CI: 0.20 – 0.24), and the basic reproduction number to be 2.37 (95%CI: 2.22-2.51) based on the assumption that the exponential growth starting from 1 March, 2020. Our estimates should be useful in preparedness planning.

scholarly journals Estimation of exponential growth rate and basic reproduction number of the coronavirus disease 2019 (COVID-19) in Africa

2020 ◽  
Vol 9 (1) ◽  
Author(s):  
Salihu S. Musa ◽  
Shi Zhao ◽  
Maggie H. Wang ◽  
Abdurrazaq G. Habib ◽  
Umar T. Mustapha ◽  
...  
Keyword(s):  
Growth Rate ◽  
Basic Reproduction Number ◽  
Exponential Growth ◽  
Reproduction Number ◽  
Exponential Growth Rate

scholarly journals Estimation of the basic reproduction number (R0) for the novel coronavirus disease in Sri Lanka

2020 ◽  
Vol 17 (1) ◽  
Author(s):  
Samath Dharmaratne ◽  
Supun Sudaraka ◽  
Ishanya Abeyagunawardena ◽  
Kasun Manchanayake ◽  
Mahen Kothalawala ◽  
...  
Keyword(s):  
Growth Rate ◽  
Maximum Likelihood ◽  
Sri Lanka ◽  
Basic Reproduction Number ◽  
Exponential Growth ◽  
Reproduction Number ◽  
Likelihood Method ◽  
Exponential Growth Rate ◽  
Rate Method ◽  
The Basic Reproduction Number

Abstract Background The basic reproduction number (R0) is the number of cases directly caused by an infected individual throughout his infectious period. R0 is used to determine the ability of a disease to spread within a given population. The reproduction number (R) represents the transmissibility of a disease. Objectives We aimed to calculate the R0 of Coronavirus disease-2019 (COVID-19) in Sri Lanka and to describe the variation of R, with its implications to the prevention and control of the disease. Methods Data was obtained from daily situation reports of the Epidemiology Unit, Sri Lanka and a compartmental model was used to calculate the R0 using estimated model parameters. This value was corroborated by using two more methods, the exponential growth rate method and maximum likelihood method to obtain a better estimate for R0. The variation of R was illustrated using a Bayesian statistical inference-based method. Results The R0 calculated by the first model was 1.02 [confidence interval (CI) of 0.75–1.29] with a root mean squared error of 7.72. The exponential growth rate method and the maximum likelihood estimation method yielded an R0 of 0.93 (CI of 0.77–1.10) and a R0 of 1.23 (CI of 0.94–1.57) respectively. The variation of R ranged from 0.69 to 2.20. Conclusion The estimated R0 for COVID-19 in Sri Lanka, calculated by three different methods, falls between 0.93 and 1.23, and the transmissibility R has reduced, indicating that measures implemented have achieved a good control of disease.

scholarly journals Estimating the basic reproduction number for COVID-19 in Western Europe

PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0248731
Author(s):  
Isabella Locatelli ◽  
Bastien Trächsel ◽  
Valentin Rousson
Keyword(s):  
Growth Rate ◽  
Basic Reproduction Number ◽  
Exponential Growth ◽  
Cumulative Incidence ◽  
Western Europe ◽  
Reproduction Number ◽  
European Population ◽  
Exponential Growth Rate ◽  
Official Statistics ◽  
The Basic Reproduction Number

Objective To estimate the basic reproduction number (R0) for COVID-19 in Western Europe. Methods Data (official statistics) on the cumulative incidence of COVID-19 at the start of the outbreak (before any confinement rules were declared) were retrieved in the 15 largest countries in Western Europe, allowing us to estimate the exponential growth rate of the disease. The rate was then combined with estimates of the distribution of the generation interval as reconstructed from the literature. Results Despite the possible unreliability of some official statistics about COVID-19, the spread of the disease appears to be remarkably similar in most European countries, allowing us to estimate an average R0 in Western Europe of 2.2 (95% CI: 1.9–2.6). Conclusions The value of R0 for COVID-19 in Western Europe appears to be significantly lower than that in China. The proportion of immune persons in the European population required to stop the outbreak could thus be closer to 50% than to 70%.

scholarly journals Epidemic Potential of COVID-19 in Omsk Region during Anti-Epidemic Measures

2020 ◽  
pp. 36-42
Author(s):  
A. I. Blokh ◽  
N. A. Pen’evskaya ◽  
N. V. Rudakov ◽  
I. I. Lazarev ◽  
O. A. Mikhailova ◽  
...  
Keyword(s):  
Growth Rate ◽  
Exponential Growth ◽  
Reproduction Number ◽  
Herd Immunity ◽  
Case Fatality ◽  
Community Acquired Pneumonia ◽  
Cumulative Number ◽  
Exponential Growth Rate ◽  
Epidemic Size ◽  
Threshold Data

Aim. To study the spread of COVID-19 among the population of the Omsk Region during 24 weeks of the epidemic on the background of anti-epidemic measures.Materials and methods. A descriptive epidemiological study was carried out based on publically available data и data from the Center for Hygiene and Epidemiology in the Omsk Region on the official registration and epidemiological investigation of detected COVID-19 cases in the Omsk Region for the period from March 27 to September 10, 2020. To assess the potential of COVID-19 to spread, the following indicators were calculated: exponential growth rate (r), basic reproduction number (R0), effective reproduction number (Rt), expected natural epidemic size and herd immunity threshold. Data processing was performed using MS Excel 2010. The cartogram was built using the QGIS 3.12-Bukuresti application in the EPSG: 3576 coordinate system.Results and discussion. For the period from March 27 to September 10, 2020, a total of 9779 cases of COVID-19 were registered in the Omsk Region, the cumulative incidence was 507,6 per 100000 (95 % CI 497,5÷517,6), the case-fatality rate for completed cases was 2.9 %, for identified cases – 2.4 %. The most active spread of COVID-19 was noted in Omsk and 4 out of 32 districts of the region (Moskalensky, Azov German National, Mariyanovsky, Novovarshavsky). During the ongoing anti-epidemic measures, the exponential growth rate of the cumulative number of COVID-19 cases was 4.5 % per day, R0 – 1.4–1.5, Rt – 1.10, herd immunity threshold – 28.6 %. The expected size of the epidemic in case of sustained anti-epidemic measures can reach 58.0 % of the recovered population. A decrease in the number of detected virus carriers, incomplete detection of COVID-19 among patients with community-acquired pneumonia introduced additional risks for the latent spread of infection and complications of the epidemic situation. Maintaining restrictive  measures and increasing the proportion of the immune population (over 28.6 %) may significantly reduce the risks of increasing the spread of COVID-19 in the Omsk Region. 

scholarly journals Estimation of the basic reproduction number of novel coronavirus (COVID-19) in Bangladesh: A 65-day outbreak data-driven analysis

2020 ◽  
Author(s):  
Md. Hasan ◽  
Akhtar Hossain ◽  
Wasimul Bari ◽  
Syed Shariful Islam
Keyword(s):  
Growth Model ◽  
Basic Reproduction Number ◽  
Exponential Growth ◽  
Reproduction Number ◽  
Fold Increase ◽  
Reporting Rate ◽  
Basic Reproductive Number ◽  
Exponential Growth Model ◽  
Novel Coronavirus ◽  
The Basic Reproduction Number

Abstract BackgroundThe outbreak of novel coronavirus disease (COVID-19), started from Wuhan, China, at the end of December 2019, hits almost the entire world. In Bangladesh, the first case was officially reported on March 8, 2020. We estimated the basic reproductive number, R0, of COVID-19 for Bangladesh using the first 65-day data of the outbreak.MethodsWith time-varying disease reporting rate, epidemic curves were estimated using the exponential growth model utilizing daily COVID-19 diagnosis data in Bangladesh from March 8 to May 11, 2020. We estimated R0 using the estimated intrinsic growth rate (γ). Serial intervals (SI) have been used from two well-known coronaviruses’ outbreaks, SARS and MERS; and the early estimate of SI of COVID-19 in Wuhan, China.ResultsThe COVID-19 epidemic in Bangladesh followed an exponential growth model. We found the R0 to be 1.84 [95% CI: 1.82–1.86], 1.82 [95% CI: 1.81–1.84], and 1.94 [95% CI: 1.92–1.96], for MERS, COVID-19, and SARS SI respectively without adjusting reporting rate. With the adjusted reporting rate, R0 reduced to 1.63 [95% CI: 1.62–1.65], 1.62 [95% CI: 1.61–1.64], and 1.71 [95% CI: 1.70–1.73] for a five-fold increase. Inverse association between the reporting rate and the basic reproduction number was observed.ConclusionThe R0 was found to be 1.87 for existing cases and was reduced to 1.65 for the five-fold increase of the early reporting rate. Findings suggest a continued COVID-19 outbreak in Bangladesh and immediate steps need to be taken to control.

scholarly journals Estimating the under-ascertainment number of COVID-19 cases in Kano, Nigeria in the fourth week of April 2020: a modelling analysis of the early outbreak

2020 ◽  
Author(s):  
Salihu S Musa ◽  
Shi Zhao ◽  
Nafiu Hussaini ◽  
Zian Zuang ◽  
Yushan Wu ◽  
...  
Keyword(s):  
Exponential Growth ◽  
Reproduction Number ◽  
Arima Model ◽  
Likelihood Estimation ◽  
Reporting Rate ◽  
Initial Growth ◽  
Short Term ◽  
First Case ◽  
Modelling Analysis ◽  
The Basic Reproduction Number

Abstract Background: The coronavirus disease 2019 (known as COVID-19) pandemic caused by Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) appeared in Wuhan, China has rapidly spread to over 200 countries and territories. In Nigeria, the Kano State Ministry of Health has confirmed its first case of COVID-19 on April 11, 2020, and since then there might have been issues of under-ascertainment that occurred roughly from 22 to 27 April 2020. As of 4 October 2020, there were 1738 reported COVID-19 cases in Kano with 54 associated deaths. In this work, we estimate the number of under-ascertainment cases and the basic reproduction number, B, of COVID-19 in Kano, Nigeria. We also predict the number of COVID-19 cases in the short term.Methods: We employ the exponential growth and modelled the outbreak curve of COVID-19 cases, in Kano, Nigeria from 11 to 30 April 2020. We estimated the number of under-ascertainment cases using the maximum likelihood estimation. We adopted the SI estimated for Hong Kong as approximations of the unknown SI for COVID-19 in Kano to estimate the a. We use ARIMA model to provide a short term (15 days) prediction of the COVID-19 cases in Kano, Nigeria.Results: We revealed that the initial growth phase mimic an exponential growth pattern. We found that the under-ascertainment was likely to have resulted in 213 (95% CI: 106−346) unreported cases from 22 to 27 April 2020. The reporting rate after 27 April 2020 increase up to 10-fold compared to the scenario from 22 to 27 April 2020 on average. We estimated the c of COVID-19 in Kano as 2.74 (95% CI: 2.53−2.96). We forecasted that the total number of COVID-19 cases in Kano to be 1067 (95% CI: 883, 2137) by June 6, 2020.Conclusion: The under-ascertainment likely exists during the fourth week of April, 2020 and should be regarded in the future analysis/investigation.

scholarly journals Estimation of the Basic Reproduction Number of SARS-CoV-2 in Bangladesh Using Exponential Growth Method

2020 ◽  
Author(s):  
Riaz Mahmud ◽  
H. M. Abrar Fahim Patwari
Keyword(s):  
Standard Deviation ◽  
Basic Reproduction Number ◽  
Exponential Growth ◽  
Generation Time ◽  
Reproduction Number ◽  
First Case ◽  
The World ◽  
Growth Method ◽  
Novel Coronavirus ◽  
The Basic Reproduction Number

Objectives: In December 2019, a novel coronavirus (SARS-CoV-2) outbreak emerged in Wuhan, Hubei Province, China. Soon, it has spread out across the world and become an ongoing pandemic. In Bangladesh, the first case of novel coronavirus (SARS-CoV-2) was detected on March 8, 2020. Since then, not many significant studies have been conducted to understand the transmission dynamics of novel coronavirus (SARS-CoV-2) in Bangladesh. In this study, we estimated the basic reproduction number R0 of novel coronavirus (SARS-CoV-2) in Bangladesh. Methods: The data of daily confirmed cases of novel coronavirus (SARS-CoV-2) in Bangladesh and the reported values of generation time of novel coronavirus (SARS-CoV-2) for Singapore and Tianjin, China, were collected. We calculated the basic reproduction number R0 by applying the exponential growth (EG) method. Epidemic data of the first 76 days and different values of generation time were used for the calculation. Results: The basic reproduction number R0 of novel coronavirus (SARS-CoV-2) in Bangladesh is estimated to be 2.66 [95% CI: 2.58-2.75], optimized R0 is 2.78 [95% CI: 2.69-2.88] using generation time 5.20 with a standard deviation of 1.72 for Singapore. Using generation time 3.95 with a standard deviation of 1.51 for Tianjin, China, R0 is estimated to be 2.15 [95% CI: 2.09-2.20], optimized R0 is 2.22 [95% CI: 2.16-2.29]. Conclusions: The calculated basic reproduction number R0 of novel coronavirus (SARS-CoV-2) in Bangladesh is significantly higher than 1, which indicates its high transmissibility and contagiousness.

scholarly journals Epidemic potential of COVID-19 in Omsk region and assessment of the anti-epidemic measures

2020 ◽  
Vol 5 (3) ◽  
pp. 8-17
Author(s):  
A. I. Blokh ◽  
N. A. Penievskaya ◽  
N. V. Rudakov ◽  
I. I. Lazarev
Keyword(s):  
Growth Rate ◽  
Exponential Growth ◽  
Reproduction Number ◽  
Herd Immunity ◽  
Case Fatality ◽  
Community Acquired Pneumonia ◽  
Exponential Growth Rate ◽  
Epidemic Size ◽  
Restrictive Measures ◽  
Observation Period

Aim. To study the spread of COVID-19 among the population of the Omsk region during the first 115 days of the epidemic. Materials and Methods. We carried out a descriptive epidemiological study using the data from the Center for Hygiene and Epidemiology in the Omsk Region on the officially registered cases of COVID-19 in the Omsk Region from March 27 to July 19, 2020. The following indicators were calculated: exponential growth rate (r), basic reproduction number (R0), effective reproduction number (Rt), expected natural epidemic size and herd immunity threshold. Results. During the indicated period, there were 5,503 cases of COVID-19 in the Omsk Region. The incidence rate was 285.60/ 0000 (95% CI 278.1 – 293.2), the case fatality rate was 1.5% for completed cases and 0.9^ for all cases. The most active spread of COVID-19 was noted in Omsk and in 5 out of 32 districts of the region (Kalachinskiy, Novovarshavskiy, Russko-Polyanskiy, Moskalenskiy, and Azov German National District). Individuals < 30 years of age were among the least involved in the epidemic process. Among the most affected groups were 55-69 years-old males and 50-64-years-old females. During the observation period, the proportion of asymptomatic forms gradually reduced along with the increase in the proportion of pneumonia cases. A manifold increase in the incidence of community-acquired pneumonia was registered in June and July 2020 compared to the average values in 2017-2019. The exponential growth rate was 6.6% per day, R0 was 1.4-1.5, Rt was 1.18, and herd immunity threshold was 28.6%. The expected size of the epidemic at sustained anti-epidemic measures was 58.0% of the population. Conclusion. The spread of COVID-19 in the Omsk region is not sufficiently suppressed. Reduced number of asymptomatic cases and incomplete detection of COVID-19 among the patients with community-acquired pneumonia may contribute to the latent spread of the infection and complicated epidemic situation. Maintenance of the restrictive measures and acquirement of the herd immunity (over 28.6% population) may significantly reduce the spread of COVID-19 in the Omsk Region.

Sign in / Sign up

Export Citation Format

Share Document