Effect of mutation and vaccination on spread, severity, and mortality of COVID-19 disease.

Coronavirus disease 2019 (COVID-19) has had different waves within the same country. The spread rate and severity showed different properties within the COVID-19 different waves. The present work aims to compare the spread and the severity of the different waves using the available data of confirmed COVID-19 cases and death cases. Real-data sets collected from the Johns Hopkins University Center for Systems Science were used to perform a comparative study between COVID-19 different waves in 12 countries with the highest total performed tests for severe acute respiratory syndrome coronavirus 2 detection in the world (Italy, Brazil, Japan, Germany, Spain, India, USA, UAE, Poland, Colombia, Turkey, and Switzerland). The total number of confirmed cases and death cases in different waves of COVID-19 were compared to that of the previous one for equivalent periods. The total number of death cases in each wave was presented as a percentage of the total number of confirmed cases for the same periods. In all the selected 12 countries, Wave 2 had a much higher number of confirmed cases than that in Wave 1. However, the death cases increase was not comparable with that of the confirmed cases to the extent that some countries had lower death cases than in Wave 1, UAE, and Spain. The death cases as a percentage of the total number of confirmed cases in Wave 1 were much higher than that in Wave 2. Some countries have had Waves 3 and 4. Waves 3 and 4 have had lower confirmed cases than Wave 2, however, the death cases were variable in different countries. The death cases in Waves 3 and 4 were similar to or higher than Wave 2 in most countries. Wave 2 of COVID-19 had a much higher spread rate but much lower severity resulting in a lower death rate in Wave 2 compared with that of the first wave. Waves 3 and 4 have had lower confirmed cases than Wave 2; that could be due to the presence of appropriate treatment and vaccination. However, that was not reflected in the death cases, which were similar to or higher than Wave 2 in most countries. Further studies are needed to explain these findings.

A study of the possible factors affecting COVID-19 spread, severity and mortality and the effect of social distancing on these factors: Machine learning forecasting model.

BACKGROUNDS: SARS-CoV-2 is affecting different countries all over the world, with significant variation in infection-rate and death-ratio. We have previously shown a presence of a possible relationship between different variables including the Bacillus Calmette-Guérin (BCG) vaccine, average age, gender, and malaria treatment, and the rate of spread, severity and mortality of COVID-19 disease. This paper focuses on developing machine learning models for this relationship. METHODS: We have used real-datasets collected from the Johns Hopkins University Center for Systems Science and Engineering and the European Centre for Disease Prevention and Control to develop a model from China data as the baseline country. From this model, we predicted and forecasted different countries' daily confirmed-cases and daily death-cases and examined if there was any possible effect of the variables mentioned above. RESULTS: The model was trained based on China data as a baseline model for daily confirmed-cases and daily death-cases. This machine learning application succeeded in modelling and forecasting daily confirmed-cases and daily death-cases. The modelling and forecasting of viral spread resulted in four different regions; these regions were dependent on the malarial treatments, BCG vaccination, weather conditions, and average age. However, the lack of social distancing resulted in variation in the effect of these factors, for example, double-humped spread and mortality cases curves and sudden increases in the spread and mortality cases in different countries. The process of machine learning for time-series prediction and forecasting, especially in the pandemic COVID-19 domain, proved usefulness in modelling and forecasting the end status of the virus spreading based on specific regional and health support variables. CONCLUSION: From the experimental results, we confirm that COVID-19 has a very low spread in the African countries with all the four variables (average young age, hot weather, BCG vaccine and malaria treatment); a very high spread in European countries and the USA with no variable (old people, cold weather, no BCG vaccine and no malaria). The effect of the variables could be on the spread or the severity to the extent that the infected subject might not have symptoms or the case is mild and can be missed as a confirmed-case. Social distancing decreases the effect of these factors.

SARS-CoV-2 infection among asymptomatic healthcare workers of the emergency department in a tertiary care facility.

BACKGROUND: Healthcare workers (HCWs) represent a high-risk category during the coronavirus disease 2019 (COVID-19) pandemic crisis, with frontline HCWs at emergency departments (EDs) may be at an even higher risk. Determining the spread of infection among HCWs may have implications for infection control policies in hospitals. This study aimed to detect severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection among asymptomatic HCWs of the ED of a large tertiary center in Cairo, Egypt. METHODS: The study was conducted from June 1st to June 14th, 2020. All the recommended national and international indications on infection control measures were followed. Two hundred and three HCWs were included in the study and tested by nasopharyngeal swab (NPS) and rapid serological test (RST). Descriptive statistical analyses were used to summarize the data. RESULTS: Of the 203 HCWs, 29 (14.3 %) tested positive by real-time reverse transcription polymerase chain reaction (RT-PCR). Thirty-seven (18.2 %) HCWs tested positive with RST: 20 with both IgM and IgG; 14 with IgM only, and 3 with IgG only. Age, gender, and/or occupation were not risk factors for SARS-CoV-2 infection. CONCLUSIONS: Point prevalence of COVID-19 in asymptomatic HCWs in ED of tertiary care facility is 14.3 % by RT-PCR. This illustrates the importance of screening all HCWs regardless of symptoms, and the need for strict measures in securing HCWs to reduce transmission from healthcare facilities to the community during the current pandemic.

The Coronaviruses of Animals and Birds: Their Zoonosis, Vaccines, and Models for SARS-CoV and SARS-CoV2.

The viruses of the family Coronaviridae are ubiquitous in nature due to their existence in a wide spectrum of mammals and avian species. The coronaviruses, as RNA viruses, exist as quasispecies because of their high rate of mutations. This review elaborates on the pathogenesis and the developed vaccines of most of the ubiquitous coronavirus' diseases, mainly bovine, dromedary camel, porcine, feline, canine, and avian coronaviruses. The review emphasizes the significant setbacks in the full exploitation of most of the pathogenesis of the coronavirus' diseases, raising the prospect of effective vaccines for these diseases. The therapeutical trials for the treatment of SARS-CoV2 and the setbacks of these trials are also addressed. The review draws attention to the lessons accumulated from the large number of studies of the pathogenesis of animals and birds' coronaviruses and their vaccines, particularly the bovine, feline, and avian coronaviruses. The lessons drawn from the studies will have an immense influence on how the human coronaviruses pathogenesis and vaccine development will proceed. In addition, the extensive efforts to designate suitable animal models to study the lately emerged human coronaviruses are one of the invaluable contributions carried out by veterinarian scientists. Finally, factors and determinants that contribute to the possibility of emerging new coronavirus zoonotic disease are elaborated on and a call goes out to urge transdisciplinary collaboration in the implementation of the "One Health" concept.

Bacillus Calmette-Guérin vaccine, antimalarial, age and gender relation to COVID-19 spread and mortality.

COVID-19 is affecting different countries all over the world with great variation in infection rate and death ratio. Some reports suggested a relation between the Bacillus Calmette-Guérin (BCG) vaccine and the malaria treatment to the prevention of SARS-CoV-2 infection. Some reports related infant's lower susceptibility to the COVID-19. Some other reports a higher risk in males compared to females in such COVID-19 pandemic. Also, some other reports claimed the possible use of chloroquine and hydroxychloroquine as prophylactic in such a pandemic. The present commentary is to discuss the possible relation between those factors and SARS-CoV-2 infection.