scholarly journals Age and Infectious Dose Significantly Affect Disease Progression after RHDV2 Infection in Naïve Domestic Rabbits

Viruses ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1184
Author(s):  
Robyn N. Hall ◽  
Tegan King ◽  
Tiffany O’Connor ◽  
Andrew J. Read ◽  
Jane Arrow ◽  
...  
Keyword(s):  
New Zealand ◽  
Disease Progression ◽  
Case Fatality Rate ◽  
Low Dose ◽  
Case Fatality ◽  
Wild Rabbit ◽  
Fatality Rate ◽  
Infectious Dose ◽  
Welfare Impacts ◽  
Rabbit Haemorrhagic Disease

Rabbit haemorrhagic disease virus 2 (RHDV2 or GI.2, referring to any virus with lagovirus GI.2 structural genes) is a recently emerged calicivirus that causes generalised hepatic necrosis and disseminated intravascular coagulation leading to death in susceptible lagomorphs (rabbits and hares). Previous studies investigating the virulence of RHDV2 have reported conflicting results, with case fatality rates ranging from 0% to 100% even within a single study. Lagoviruses are of particular importance in Australia and New Zealand where they are used as biocontrol agents to manage wild rabbit populations, which threaten over 300 native species and result in economic impacts in excess of $200 million AUD annually to Australian agricultural industries. It is critically important that any pest control method is both highly effective (i.e., virulent, in the context of viral biocontrols) and has minimal animal welfare impacts. To determine whether RHDV2 might be a suitable candidate biocontrol agent, we investigated the virulence and disease progression of a naturally occurring Australian recombinant RHDV2 in both 5-week-old and 11-week-old New Zealand White laboratory rabbits after either high or low dose oral infection. Objective measures of disease progression were recorded through continuous body temperature monitoring collars, continuous activity monitors, and twice daily observations. We observed a 100% case fatality rate in both infected kittens and adult rabbits after either high dose or low dose infection. Clinical signs of disease, such as pyrexia, weight loss, and reduced activity, were evident in the late stages of infection. Clinical disease, i.e., welfare impacts, were limited to the period after the onset of pyrexia, lasting on average 12 h and increasing in severity as disease progressed. These findings confirm the high virulence of this RHDV2 variant in naïve rabbits. While age and infectious dose significantly affected disease progression, the case fatality rate was consistently 100% under all conditions tested.

scholarly journals Age and infectious dose significantly affect disease progression after RHDV2 infection in naive domestic rabbits

2021 ◽  
Author(s):  
Robyn N Hall ◽  
Tegan King ◽  
Tiffany O'Connor ◽  
Andrew J Read ◽  
Jane Arrow ◽  
...  
Keyword(s):  
New Zealand ◽  
Disease Progression ◽  
Case Fatality Rate ◽  
Low Dose ◽  
Case Fatality ◽  
Wild Rabbit ◽  
Fatality Rate ◽  
Infectious Dose ◽  
Welfare Impacts ◽  
Rabbit Haemorrhagic Disease

Rabbit haemorrhagic disease virus 2 (RHDV2 or GI.2, referring to any virus with lagovirus GI.2 structural genes) is a recently emerged calicivirus that causes generalised hepatic necrosis and disseminated intravascular coagulation leading to death in susceptible lagomorphs (rabbits and hares). Previous studies investigating the virulence of RHDV2 have reported conflicting results, with case fatality rates ranging from 0% to 100% even within a single study. Lagoviruses are of particular importance in Australia and New Zealand where they are used as biocontrol agents to manage wild rabbit populations; wild rabbits threaten over 300 native species and result in economic impacts in excess of $200 million AUD to Australian agricultural industries. It is critically important that any pest control method is both highly effective (i.e., virulent, in the context of viral biocontrols) and has minimal animal welfare impacts. To determine whether RHDV2 might be a suitable candidate biocontrol agent, we investigated the virulence and disease progression of a naturally occurring Australian recombinant RHDV2 in both 5-week-old and 11-week-old New Zealand White laboratory rabbits after either high or low dose oral infection. Objective measures of disease progression were recorded through continuous body temperature monitoring collars, continuous activity monitors, and twice daily observations. We observed a 100% case fatality rate in both infected kittens and adult rabbits after either high dose or low dose infection. Clinical signs of disease, such as pyrexia, weight loss, and reduced activity, were evident in the late stages of infection. Clinical disease, i.e., welfare impacts, were limited to the period after the onset of pyrexia, lasting on average 12 hours and increasing in severity as disease progressed. These findings confirm the high virulence of this RHDV2 variant in naive rabbits. While age and infectious dose significantly affected disease progression, the case fatality rate was consistently 100% under all conditions tested.

scholarly journals Key to successful treatment of COVID-19: accurate identification of severe risks and early intervention of disease progression

2020 ◽  
Author(s):  
Meizhu Chen ◽  
Changli Tu ◽  
Cuiyan Tan ◽  
Xiaobin Zheng ◽  
Xiaohua Wang ◽  
...  
Keyword(s):  
Mechanical Ventilation ◽  
Early Intervention ◽  
Disease Progression ◽  
Case Fatality Rate ◽  
Severe Disease ◽  
Invasive Mechanical Ventilation ◽  
Case Fatality ◽  
List Type ◽  
Fatality Rate ◽  
Medical Burden

AbstractBackgroundCOVID-19 is a new and highly contagious respiratory disease that has caused global spread, high case fatality rate in severe patients, and a huge medical burden due to invasive mechanical ventilation. The current diagnosis and treatment guidelines are still need to be improved, and more excellent clinical experience is needed to provide reference.MethodsWe analyzed and summarized clinical data of 97 confirmed COVID-19 adult patients (including 26 severe cases) admitted to the Fifth Affiliated Hospital of Sun Yat-sen University from January 17, 2020 to March 10, 2020, included laboratory examination results, imaging findings, treatment effect, prognosis, etc, in order to put forward prediction index of severe COVID-19 patients, principles of early intervention and methylprednisolone usages in COVID-19 patients.ResultsHypoxemia, hyperlactic acid, hypoproteinemia, and hypokalemia were prevalent in COVID-19 patients. The significant low lymphocyte count, hypoproteinemia, hypokalemia, the persistent or worsen high CRP, high D-dimer, and high BNP, and the occurrence of hemoptysis and novel coronavirus (SARS-CoV-2) viremia were important indicators for early diagnosis and prediction of severe disease progression.Characteristic images of lung CT had a clear change in COVID-19, Ground-glass opacity (GGO) and high-density linear combinations may indicate different pathological changes. Rapid lobular progression of GGO suggests the possibility of severe disease.Basic principles of early intervention treatment of COVID-19: on the premise of no effective antiviral drugs, treatment is based on supportive and symptomatic therapy (albumin supplementation, supplement of potassium, supplement blood plasma, etc.) in order to maintain the stability of the intracellular environment and adequately reactivate body immunity to clean up SARS-CoV-2.According to severity, oxygenation index, body weight, age, underlying diseases, appropriate amount methylprednisolone application on severe/critical COVID-19 patients on demand, improved blood oxygen and reduced the utilization rate of invasive mechanical ventilation, case fatality rate and medical burden significantly. The most common indications for invasive mechanical ventilation should be strictly control in critical COVID-19 patients.ConclusionsAccurate and timely identification of clinical features in severe risks, and early and appropriate intervention can block disease progression. 2. Appropriate dose of methylprednisolone can effectively avoid invasive mechanical ventilation and reduce case fatality rate in critical COVID-19 patients.

scholarly journals Trends in case-fatality rates of COVID-19 in the World, between 2019 - 2020

2020 ◽  
Vol 30 (3) ◽  
pp. 344-354
Author(s):  
Henrique de Moraes Bernal ◽  
Carlos Eduardo Siqueira ◽  
Fernando Adami ◽  
Edige Felipe de Sousa Santos
Keyword(s):  
South Africa ◽  
Saudi Arabia ◽  
United Kingdom ◽  
New Zealand ◽  
Case Fatality Rate ◽  
Case Fatality ◽  
The Other ◽  
Fatality Rate ◽  
The World ◽  
Increasing Trends

Introduction: CoV infections can potentially cause from a simple cold to a severe respiratory syndrome, such as the Severe Acute Respiratory Syndrome and the Middle East Respiratory Syndrome (MERS-CoV). The COVID-19 created a new reality for global healthcare models. Objetive: To evaluate trends in case fatality rates of COVID-19 in the World. Methods: We conducted a population based time-series study using public and official data of cases and deaths from COVID-19 in Argentina, Australia, Brazil, Chile, China, Colombia, France, Germany, India, Iran, Italy, Japan, Mexico, Morocco, New Zealand, Nigeria, Peru, Saudi Arabia, South Africa, South Korea, Spain, Switzerland, United Kingdom, United States and Russian, between December, 2019 and August, 2020. Data were based on reports from European Centre for Disease Prevention and Control. COVID-19 was defined by the International Classification of Diseases, 10th revision (U07.1). A Prais-Winsten regression model was performed and the Daily Percentage Change (DPC) calculated determine rates as increasing, decreasing or flat. Results: During the study period, trends in case-fatality rates in the world were flat (DPC = 0.3; CI 95% [-0.2: 0.7]; p = 0.225). In Africa, Morocco had decreasing trends (DPC = -1.1; CI 95% [-1.5: -0.7]; p < 0.001), whereas it were increasing in South Africa (p < 0.05) and flat in Nigeria (p > 0.05). In the Americas, Argentina showed a decreasing trend in case-fatality rates (DPC = -0.6; CI 95% [-1.1: -0.2]; p = 0.005), the U.S. had flat trends (p > 0.05) and all other American countries had increasing trends (p < 0.05). In Asia, Iran had decreasing trends (DPC = -1.5; CI 95% [-2.6 : -0.2]; p = 0.019); China and Saudi Arabia showed increasing trends (p < 0.05), while in India, Japan and South Korea they were flat (p > 0.05). European countries had mostly increasing trends (p < 0.05): Germany, Italy, Spain, the UK and Russia; France and Switzerland had flat trends (p > 0.05). Finally, in Oceania, trends in case-fatality rates were flat in Australia (p > 0.05) and increasing in New Zealand (p < 0.05). Conclusion: Trends in case-fatality rates of COVID-19 in the World were flat between December, 31 and August, 31. Argentina, Iran and Morocco were the only countries with decreasing trends. On the other hand, South Africa, Brazil, Canada, Chile, Colombia, Mexico, Peru, China, Saudi Arabia, Germany, Spain, United Kingdom, Russian and New Zealand had increasing trends in case-fatality rate. All the other countries analyzed had flat trends. Based on case-fatality rate data, our study supports that COVID-19 pandemic is still in progress worldwide.

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 Regional Variability in COVID-19 Case Fatality Rate in Canada, February–December 2020

2021 ◽  
Vol 18 (4) ◽  
pp. 1839
Author(s):  
Eunha Shim
Keyword(s):  
British Columbia ◽  
Case Fatality Rate ◽  
Case Reports ◽  
Case Fatality ◽  
Health Interventions ◽  
Fatality Rate ◽  
Older Individuals ◽  
Regional Variability ◽  
Provincial Level ◽  
Mortality Burden

A total of 475,214 COVID-19 cases, including 13,659 deaths, had been recorded in Canada as of 15 December 2020. The daily reports of confirmed cases and deaths in Canada prior to 15 December 2020 were obtained from publicly available sources and used to examine regional variations in case fatality rate (CFR). Based on a factor of underestimation and the duration of time from symptom onset to death, the time-delay adjusted CFR for COVID-19 was estimated in the four most affected provinces (Quebec, Ontario, Alberta, and British Columbia) and nationwide. The model-based adjusted CFR was higher than the crude CFR throughout the pandemic, primarily owing to the incorporation in our estimation of the delay between case reports and deaths. The adjusted CFR in Canada was estimated to be 3.36% nationwide. At the provincial level, the adjusted CFR was the highest in Quebec (5.13%)—where the proportion of deaths among older individuals was also the highest among the four provinces—followed by Ontario (3.17%), British Columbia (1.97%), and Alberta (1.13%). Provincial-level variations in CFR were considerable, suggesting that public health interventions focused on densely populated areas and elderly individuals can ameliorate the mortality burden of the COVID-19 pandemic.

scholarly journals Population-Predicted MHC Class II Epitope Presentation of SARS-CoV-2 Structural Proteins Correlates to the Case Fatality Rates of COVID-19 in Different Countries

2021 ◽  
Vol 22 (5) ◽  
pp. 2630
Author(s):  
Chunguang Liang ◽  
Elena Bencurova ◽  
Eric Psota ◽  
Priya Neurgaonkar ◽  
Martina Prelog ◽  
...  
Keyword(s):  
Mhc Class Ii ◽  
Case Fatality Rate ◽  
Case Fatality ◽  
Class Ii ◽  
Viral Envelope ◽  
Structural Proteins ◽  
P Value ◽  
Fatality Rate ◽  
Different Populations ◽  
Infection Spread

We observed substantial differences in predicted Major Histocompatibility Complex II (MHCII) epitope presentation of SARS-CoV-2 proteins for different populations but only minor differences in predicted MHCI epitope presentation. A comparison of this predicted epitope MHC-coverage revealed for the early phase of infection spread (till day 15 after reaching 128 observed infection cases) highly significant negative correlations with the case fatality rate. Specifically, this was observed in different populations for MHC class II presentation of the viral spike protein (p-value: 0.0733 for linear regression), the envelope protein (p-value: 0.023), and the membrane protein (p-value: 0.00053), indicating that the high case fatality rates of COVID-19 observed in some countries seem to be related with poor MHC class II presentation and hence weak adaptive immune response against these viral envelope proteins. Our results highlight the general importance of the SARS-CoV-2 structural proteins in immunological control in early infection spread looking at a global census in various countries and taking case fatality rate into account. Other factors such as health system and control measures become more important after the early spread. Our study should encourage further studies on MHCII alleles as potential risk factors in COVID-19 including assessment of local populations and specific allele distributions.

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