scholarly journals Downward trend in the indices of death rate in the Covid-19 pandemic: Evaluating alternative hypotheses

2020 ◽  
Author(s):  
Sonali Shinde ◽  
Pratima Ranade ◽  
Milind Watve

In the ongoing Covid-19 pandemic, in the global data on the case fatality ratio and other indices reflecting death rate, there is a consistent downward trend from mid-April to mid-August. The downward trend can be an illusion caused by biases and limitations of data or it could faithfully reflect a declining death rate. A variety of explanations for this trend are possible, but a systematic analysis of the testable predictions of the alternative hypotheses has not yet been attempted. We state six testable alternative hypotheses, analyse their testable predictions using public domain data and evaluate their relative contributions to the downward trend. We show that a decline in the death rate is real; changing age structure of the infected population and evolution of the virus towards reduced virulence are the most supported hypotheses and together contribute to major part of the trend. The testable predictions from other explanations including altered testing efficiency, time lag, improved treatment protocols and herd immunity are not consistently supported, or do not appear to make a major contribution to this trend although they may influence some other patterns of the epidemic.

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11150
Author(s):  
Sonali Shinde ◽  
Pratima Ranade ◽  
Milind Watve

Background In the ongoing Covid-19 pandemic, in the global data on the case fatality ratio (CFR) and other indices reflecting death rate, there is a consistent downward trend from mid-April to mid-November. The downward trend can be an illusion caused by biases and limitations of data or it could faithfully reflect a declining death rate. A variety of explanations for this trend are possible, but a systematic analysis of the testable predictions of the alternative hypotheses has not yet been attempted. Methodology We state six testable alternative hypotheses, analyze their testable predictions using public domain data and evaluate their relative contributions to the downward trend. Results We show that a decline in the death rate is real; changing age structure of the infected population and evolution of the virus towards reduced virulence are the most supported hypotheses and together contribute to major part of the trend. The testable predictions from other explanations including altered testing efficiency, time lag, improved treatment protocols and herd immunity are not consistently supported, or do not appear to make a major contribution to this trend although they may influence some other patterns of the epidemic. Conclusion The fatality of the infection showed a robust declining time trend between mid April to mid November. Changing age class of the infected and decreasing virulence of the pathogen were found to be the strongest contributors to the trend.


Author(s):  
Milind Watve ◽  
Sonali Shinde ◽  
Pratima Ranade

In the ongoing Covid-19 pandemic, in the global data on the case fatality ratio and other indices reflecting death rate, there is a consistent downward trend from mid-April to mid-August. The downward trend can be an illusion caused by biases and limitations of data or it could faithfully reflect a declining death rate. A variety of explanations for this trend are possible, but a systematic analysis of the testable predictions of the alternative hypotheses has not yet been attempted. We state six testable alternative hypotheses, analyse their testable predictions using public domain data and evaluate their relative contributions to the downward trend. We show that a decline in the death rate is real; changing age structure of the infected population and evolution of the virus towards reduced virulence are the most supported hypotheses and together contribute to major part of the trend. The testable predictions from other explanations including altered testing efficiency, time lag, improved treatment protocols and herd immunity are not consistently supported, or do not appear to make a major contribution to this trend although they may influence some other patterns of the epidemic.


2021 ◽  
Vol 9 ◽  
Author(s):  
Priom Saha ◽  
Jahida Gulshan

Background: To develop an effective countermeasure and determine our susceptibilities to the outbreak of COVID-19 is challenging for a densely populated developing country like Bangladesh and a systematic review of the disease on a continuous basis is necessary.Methods: Publicly available and globally acclaimed datasets (4 March 2020–30 September 2020) from IEDCR, Bangladesh, JHU, and ECDC database are used for this study. Visual exploratory data analysis is used and we fitted a polynomial model for the number of deaths. A comparison of Bangladesh scenario over different time points as well as with global perspectives is made.Results: In Bangladesh, the number of active cases had decreased, after reaching a peak, with a constant pattern of death rate at from July to the end of September, 2020. Seventy-one percent of the cases and 77% of the deceased were males. People aged between 21 and 40 years were most vulnerable to the coronavirus and most of the fatalities (51.49%) were in the 60+ population. A strong positive correlation (0.93) between the number of tests and confirmed cases and a constant incidence rate (around 21%) from June 1 to August 31, 2020 was observed. The case fatality ratio was between 1 and 2. The number of cases and the number of deaths in Bangladesh were much lower compared to other countries.Conclusions: This study will help to understand the patterns of spread and transition in Bangladesh, possible measures, effectiveness of the preparedness, implementation gaps, and their consequences to gather vital information and prevent future pandemics.


Author(s):  
Deepak Sharma ◽  
Shalimar

: As most of the countries have already passed the peaks of the second or third wave of infections, COVID-19 is (finally) on the wane and will soon touch the baseline persistence with a reduced death rate. The case fatality ratio (CFR) or lethality is presently only ~2.0%, which is relatively low in comparison to the high of 14% in April 2020. More importantly, the lethality in healthy people is 20 times lower. In addition, successful vaccination programs are currently underway in several countries. Thus, although new pathogenic variants, as well as a few isolated cases of resurgence, will continue to emerge, the worst seems to be over, and we will surely win this battle soon!


Author(s):  
Mikhail Teppone

Background. January 2021 marked one year since the start of COVID-19 pandemic: it is the time of intermediate conclusions. Objective. To evaluate CFR and IFR due to COVID-19 in various countries and territories, and to study if parameters of a population age affect CFR and IFR. Material and Methods. The databases of 219 countries were collected on the Worldometers, Index Mundi, Country Meters and World Bank websites. The processing of data was divided into two parts: the first part dealt with the calculation and analysis of CFR while the second, the calculation and analysis of IFR. Results. The calculations revealed that in 74 out of 219 countries, CFR was less than 1.00 %, in 69 countries it varied between 1.00 % and 2.00 %, and in 76 countries it was more than 2.00 %. The calculation of IFR revealed that in 183 countries, IFR was less than 1.00 %, in 22 countries IFR was between 1.00 % and 2.00 %, and only in 14 out of 219 countries IFR was more than 2.00 %. A correlation between IFR and parameters of a population age was found: the less median age and the percentage of 'aged' people – the less value of IFR, although, there was no correlation between parameters of a population age and CFR. Conclusion. The global health care system has gone through a year of serious trial caused by COVID-19 and appeared to have emerged victorious. In the majority of countries analyzed, the parameters of mortality due to COVID-19 were at a low level. So, there seems to be an objective basis for optimism and hope for an early end to the pandemic.


2020 ◽  
Author(s):  
Tanishque Propkar Malik

Mathematical modelling of any epidemic plays a crucial role in quantifying the impact of such pathogens. This paper focuses on building a Stochastic SIR Model with non-linear parameters (to account for the effect of lockdowns) to gain a broader cognition of the 2019 novel Coronavirus pathogen (2019-nCov), widely known as Covid-19, in India. Such models help in gauging the virulence and fecundity of pathogens. Based on early transmission dynamics the basic reproductive number (R0) is computed to be 1.605. Whereas, effective reproductive number (Rt) is computed to be 4.880 as on 19 March, 2.756 as on 19 April, and 1.995 as on 19 May. Furthermore, the proportion of population that needs to be immunized (through inoculation, recovery, or death) to halt the infection spread is estimated to be 37.69%, ergo, the Herd Immunity Threshold is estimated to be 51.36 crores recoveries, if the Rt remains below 2. Rt is expected to fall below 2, and the Case Fatality Ratio (CFR) to fall to 2.14%, circa early-September (assuming minimal or no medical breakthroughs). The formulated model also provides inferential evidence manifesting the extent to which lockdowns contained the spread of the virus.


2021 ◽  
Author(s):  
Piyush Kumar

The first principle of medicine is Do No Harm. This is often considered a main component of the Hippocratic Oath, which of course are recited at most medical school graduations. Well, sort of. An actual translation of what is written in the Oath would be more like: “I will follow that system of regimen which, according to my ability and judgment, I consider for the benefit of my patients, and abstain from whatever is deleterious and mischievous.”In our submission we want to point out that by ignoring the Medical Knowledge established for last 100 years, and biased by western data and practice, the vaccination drive started in India is doing more harm than any good for the people of India.We present before you the scientific facts about SARS COV2 related immunity and vaccination.1.There is enough and robust evidence available now that those who have recovered from Covid 19 develop robust and long-lasting immunity against SARS CoV2, even after mild or asymptomatic infections, and those chances of reinfection among these people, even from the emerging variants of the same virus, are extremely rare or non-existent. The WHO in its interim guidance released on July 2, 2021 has also recognized the fact of acquired immunity in all those who have had previous infection with SARS-CoV-2. [1-11]2.There is no evidence to show that those who have recovered from the infection will get any additional benefit from vaccination. There is an elegant study from the Cleveland Health System which has conclusively reported that those infected do not get reinfected, whether vaccinated or not. [12-15]3.The epidemiology of Covid 19 in India is very different from other countries of the world and even within India; there are differences between urban and rural communities and between socioeconomic strata. Therefore, we need to have our own policies regarding prevention of covid19 here, including the policy on vaccination. According to available reports, the percentage of population infected in the US, UK, and such other countries is at 1-23%. In India, recent sero-surveys at Delhi and Mumbai have reported a positivity of 50-70%, indicating that a significant proportion of our people have already been infected, reaching the levels of herd immunity, and will not need the vaccine. https://www.hindustantimes.com/india-news/kids-adults-have-similar-antibodies-sero-survey-101623953000262.htmlAnd many reports of India achieving herd immunity have already appeared. The mathematical models have explained how what percentage of population is required to be infected is also different for different population and with mixing rates fitted to social activity; the disease-induced herd immunity level can be ~43%. [19-22]4.Case Fatality Rate is the rate that is usually reported by the government, which is the number of deaths per 100 confirmed cases as detected by antigen or rt-PCR test. But as renowned Epidemiologist Dr John Ioannidis, whose paper (Attached along with) on WHO site (https://www.who.int/bulletin/online_first/BLT.20.265892.pdf) shows proper way of counting death rate in diseases with CFR less than 5 is Infection Mortality Rate. That is from serosurveys the actual prevalence of the infection in community is found and death rate counted from that is Infection Fatality Rate. The IFR is less than 0.1% world over and is shown to be so in India from various serosurveys done by ICMR.5.Covid19 is now proven to be asymptomatic or mild disease with infection fatality rate of 0.001-0.01% or lower, and particularly in the population younger than 30 years, it is mostly asymptomatic and harmless. [23-26] Therefore, considering the fact of high level of infections in India, near herd immunity, and very low levels of Infection Fatality Rates, vaccinating the entire population will not serve any purpose. Looking at the negligible risk to the children from Covid-19, trial of the vaccines for them or even consideration approval is highly unethical.6. A very important development that has taken place because of 4 latest studies that proves that almost 99.9% population has the memory from previous corona infection and that whether to the actual corona infection or to vaccine it is our same immune memory gets activated and vaccines in fact are more harmful in an already immune population. Based on that Doctors for Covid Ethics have written letter to tens of thousands of doctors in Europe. “Four recent scientific discoveries are herewith brought to your urgent attention. They alter the entire landscape of the COVID-19 pandemic, and they force us to reassess the merits of vaccination against SARS-CoV-2.Keywords- India, Immunity, Infection, Covid-19, herd immunity, serosurveys, natural immunity,


Coronaviruses ◽  
2020 ◽  
Vol 01 ◽  
Author(s):  
Prafulla Kumar Swain

Background: In this paper an attempt has been made to estimate the Case Fatality Ratio (CFR) for coronavirus disease of India and few selected countries. and Also, highlighted the pros and cons of obtaining crude and adjusted CFR of COVID-19 pandemic. Material and Methods: Data extracted from WHO situation report and University of Oxford website have been used for this analysis. The CFR and its 95% confidence interval were computed, trend and bar plot was used for graphical representation. Results: The worldwide crude CFR stands 6.73% (95% CI 6.69 to 6.76) based on 21, 83, 877 confirmed and 1,46,872 death cases(as on 17th April,2020). Belgium was highest CFR 13.95% as compared to others. However, India’s CFR was found to be around 3.26% (as on 17th April, 2020). Conclusion: In conclusion, the estimation and interpretation of CFR is critical in response to ongoing COVID-19. The initial CFR estimates are subject to change, still it is useful for healthcare planning over the coming months. Moreover, the precise and robust estimates of CFR will be available only at the end of the epidemic.


Author(s):  
Jayesh S

UNSTRUCTURED Covid-19 outbreak was first reported in Wuhan, China. The deadly virus spread not just the disease, but fear around the globe. On January 2020, WHO declared COVID-19 as a Public Health Emergency of International Concern (PHEIC). First case of Covid-19 in India was reported on January 30, 2020. By the time, India was prepared in fighting against the virus. India has taken various measures to tackle the situation. In this paper, an exploratory data analysis of Covid-19 cases in India is carried out. Data namely number of cases, testing done, Case Fatality ratio, Number of deaths, change in visits stringency index and measures taken by the government is used for modelling and visual exploratory data analysis.


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