Omicron SARS-CoV-2 new variant: global prevalence and biological and clinical characteristics

OBJECTIVE: The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has created a challenging and threatening situation worldwide. The SARS-CoV-2 embodies diverse epidemiological trends, alongside emerging and reemerging pathogenic characteristics, which have raised great public health concerns. This study aims to investigate the global prevalence, biological and clinical characteristics of Omicron, a new variant of SARS-CoV-2 that is causing concern and fear internationally. MATERIALS AND METHODS: The data on the outbreak of the new variant "Omicron" was obtained from the World Health Organization ( WHO), Centers for Disease Control and Prevention (CDC), European Centre for Disease Prevention and Control (ECDC), research institutes, and global international print media. We recorded information on the prevalence, the biological and clinical characteristics of the Omicron Variant of SARS-CoV-2 from November 24 to December 9, 2021. RESULTS: Worldwide, the new variant of SARS-CoV-2, Omicron, has been identified in 57 countries with 2152 confirmed cases reported on December 9, 2021, ever since the emergence of the first case of this variant dated November 24, 2021. The number of confirmed Omicron variant cases has significantly increased globally. The novel variant is spreading swiftly and has crossed many borders all around the world. This new variant has been observed to be transmitted far more rapidly than other variants of SARS-CoV-2. CONCLUSIONS: The new variant of SARS-CoV-2 has novel epidemiological and biological characteristics, making it more contagious than other variants of SARS-CoV-2. It has affected 2152 people in 57 countries in a short period of two weeks. However, the fatality rate of the SARS-CoV-2 Omicron variant has not yet been reported. The major clinical manifestations in this new variant are those of a "mild infection", including headache, body ache, muscles ache, cough, fever, generalized myalgia, and severe fatigue. It is infecting younger and middle-aged people more than previous variants. Worldwide health establishments should take immediate preventive measures to stop outbreaks of this emerging and reemerging pathogenic variant across the globe to minimize the disease burden on humanity.

COVID-19 vaccines: comparison of biological, pharmacological characteristics and adverse effects of Pfizer/BioNTech and Moderna Vaccines.

OBJECTIVE: The "Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)" disease has caused a worldwide challenging and threatening pandemic (COVID-19), with huge health and economic losses. The US Food and Drug Administration, (FDA) has granted emergency use authorization for treatment with the Pfizer/BioNTech and Moderna COVID-19 vaccines. Many people have a history of a significant allergic reaction to a specific food, medicine, or vaccine; hence, people all over the world have great concerns about these two authorized vaccines. This article compares the pharmacology, indications, contraindications, and adverse effects of the Pfizer/BioNTech and Moderna vaccines. MATERIALS AND METHODS: The required documents and information were collected from the relevant databases, including Web of Science (Clarivate Analytics), PubMed, EMBASE, World Health Organization (WHO), Food and Drug Authorities (FDA) USA, Local Ministries, Health Institutes, and Google Scholar. The key terms used were: Coronavirus, SARS-COV-2, COVID-19 pandemic, vaccines, Pfizer/BioNTech vaccine, Moderna vaccine, pharmacology, benefits, allergic responses, indications, contraindications, and adverse effects. The descriptive information was recorded, and we eventually included 12 documents including research articles, clinical trials, and websites to record the required information. RESULTS: Based on the currently available literature, both vaccines are beneficial to provide immunity against SARS-CoV-2 infection. Pfizer/BioNTech Vaccine has been recommended to people 16 years of age and older, with a dose of 30 µg (0.3 m) at a cost of $19.50. It provides immunogenicity for at least 119 days after the first vaccination and is 95% effective in preventing the SARS-COV-2 infection. However, Moderna Vaccine has been recommended to people 18 years of age and older, with a dose of 50 µg (0.5 mL) at a cost of $32-37. It provides immunogenicity for at least 119 days after the first vaccination and is 94.5% effective in preventing the SARS-CoV-2 infection. However, some associated allergic symptoms have been reported for both vaccines. The COVID-19 vaccines can cause mild adverse effects after the first or second doses, including pain, redness or swelling at the site of vaccine shot, fever, fatigue, headache, muscle pain, nausea, vomiting, itching, chills, and joint pain, and can also rarely cause anaphylactic shock. The occurrence of adverse effects is reported to be lower in the Pfizer/BioNTech vaccine compared to the Moderna vaccine; however, the Moderna vaccine compared to the Pfizer vaccine is easier to transport and store because it is less temperature sensitive. CONCLUSIONS: The FDA has granted emergency use authorization for the Pfizer/BioNTech and Moderna COVID-19 vaccines. These vaccines can protect recipients from a SARS-CoV- 2 infection by formation of antibodies and provide immunity against a SARS-CoV-2 infection. Both vaccines can cause various adverse effects, but these reactions are reported to be less frequent in the Pfizer/BioNTech vaccine compared to the Moderna COVID-19 vaccine; however, the Moderna vaccine compared to the Pfizer vaccine is easier to transport and store because it is less temperature sensitive.

Effect of heat and humidity on the incidence and mortality due to COVID-19 pandemic in European countries.

OBJECTIVE: The weather allied conditions have an impact on air, water, soil, food, ecosystem, feelings, behaviors, and pattern of health and disease. The present study aims to investigate the impact of heat and humidity on the daily basis incidence and mortality due to COVID-19 pandemic in European countries. MATERIALS AND METHODS: We selected 10 European countries, Russia, United Kingdom, Spain, Italy, Germany, Turkey, France, Belgium, Netherlands and Belarus. This region has a relatively low temperature and high humidity, and has homogenous European ethnicity with almost similar socioeconomic culture and health care system. The data on COVID-19 pandemic including daily new cases and new deaths were recorded from World Health Organization (WHO). The information on daily temperature and humidity was obtained from world climate web "Time and Date". The daily cases, deaths, temperature and humidity were recorded from the date of appearance of first case of "Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)" in the European region, from Jan 27, 2020 to July 17, 2020. RESULTS: In 10 European countries, (Russia, United Kingdom, Spain, Italy, Germany, Turkey, France, Belgium, Netherlands and Belarus), the daily basis mean temperature from Jan 27, 2020 to July 17, 2020 was 17.07±0.18°C, and humidity was 54.78±0.47%. The overall results revealed a significant inverse correlation between humidity and the number of cases (r= -0.134, p<0.001) and deaths (r= -0.126, p<0.001). Moreover, an increase in temperature was linked with an increase in the number of cases (r=0.062, p=0.013) and deaths (r=0.118, p<0.001). The regression analysis results further revealed that with an increase of 1% humidity the number of cases (ß = -15.90, p<0.001) and deaths (ß=-1.56, p<0.001) reduced significantly. Whereas, with an increase of 1°C in temperature the number of cases (ß = 20.65, p<0.001) and deaths (ß = 3.71, p<0.001) increased significantly. CONCLUSIONS: Increase in relative humidity was associated with a decrease in the number of daily cases and deaths, however, a rise in temperature was allied with an upsurge in the number of daily cases and daily deaths due to COVID-19 pandemic in European countries. The study findings on weather events and COVID-19 pandemic have an impact at European regional levels to project the incidence and mortality trends with regional weather events to enhance public health readiness and assist in planning to fight against this pandemic situation.

Climate and COVID-19 pandemic: effect of heat and humidity on the incidence and mortality in world's top ten hottest and top ten coldest countries.

OBJECTIVE: The COVID-19 pandemic has caused a global public health crisis with social, psychological and long-lasting economical damages. Weather-related dynamics have an impact on the pattern of human health and disease. The present study aimed to investigate the impact of heat and humidity on daily basis incidence and mortality due to COVID-19 pandemic in ten of the world's hottest countries compared to ten of the coldest ones. MATERIALS AND METHODS: Worldwide, we selected 20 countries; 10 hottest countries with the highest temperatures and 10 coldest countries with the lowest temperature. The selection of the countries was based on the daily basis mean temperature from the date of appearance of the initial cases of COVID-19, Dec 29, 2019 to May 12, 2020. In the world's 10 hottest countries, the mean temperature was (26.31±1.51) and humidity (44.67±4.97). However, in the world's 10 coldest countries the mean temperature was (6.19±1.61) and humidity (57.26±2.35). The data on the global outbreak of COVID-19, daily new cases and deaths were recorded from World Health Organization, and daily information on temperature and humidity was obtained from metrological web "Time and Date". RESULTS: In countries with high temperatures and low humidity, the mean daily cases incidence were (407.12±24.33); cumulative cases (9094.34±708.29); and cumulative deaths (452.84±43.30) were significantly low compared to countries with low temperatures and high humidity: daily cases (1876.72±207.37); cumulative cases (44232.38±5875.11); and cumulative deaths (2008.29±310.13). Moreover, COVID-19 cases and deaths per million population were significantly low in countries with high temperatures (cases 711.23, and deaths 16.27) compared to countries with low temperatures (cases 1685.99; and deaths 86.40). Furthermore, in hottest countries, a 1% increase in humidity reduced number of cases and deaths by (ß = -5.40, p<0.001) and (ß = -0.187, p=0.004) respectively. A similar trend was seen with a 1°C increase in temperature, reducing the number of deaths by (ß = -1.35. p<0.001). CONCLUSIONS: The results revealed a significant decrease in incidence of daily cases and deaths in countries with high temperatures and low humidity (warmest countries), compared to those countries with low temperatures and high humidity (coldest countries). The findings could be of interest to the policymakers and the health officials on the epidemiological trends of COVID-19 pandemic and weather changes.