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.

Impact of weather conditions on incidence and mortality of COVID-19 pandemic in Africa.

OBJECTIVE: The weather-related conditions change the ecosystem and pose a threat to social, economic and environmental development. It creates unprecedented or unanticipated human health problems in various places or times of the year. Africa is the world's second largest and most populous continent and has relatively changeable weather conditions. The present study aims to investigate the impact of weather conditions, heat and humidity on the incidence and mortality of COVID-19 pandemic in various regions of Africa. MATERIALS AND METHODS: In this study, 16 highly populated countries from North, South, East, West, and Central African regions were selected. The data on COVID-19 pandemic including daily new cases and new deaths were recorded from World Health Organization. The daily temperature and humidity figures were obtained from the weather 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 African region, from Feb 14 to August 2, 2020. RESULTS: In African countries, the daily basis mean temperature from Feb 14, 2020 to August 2, 2020 was 26.16±0.12°C, and humidity was 57.41±0.38%. The overall results revealed a significant inverse correlation between humidity and the number of cases (r= -0.192, p<0.001) and deaths (r= -0.213, p<0.001). Similarly, a significant inverse correlation was found between temperature and the number of cases (r= -0.25, p<0.001) and deaths (r=-0.18, p<0.001). Furthermore, the regression results showed that with 1% increase in humidity the number of cases and deaths was significantly reduced by 3.6% and 3.7% respectively. Congruently, with 1°C increase in temperature, the number of cases and deaths was also significantly reduced by 15.1% and 10.5%, respectively. CONCLUSIONS: Increase in relative humidity and temperature was associated with a decrease in the number of daily cases and deaths due to COVID-19 pandemic in various African countries. The study findings on weather events and COVID-19 pandemic have an impact at African regional levels to project the incidence and mortality trends with regional weather events which will enhance public health readiness and assist in planning to fight against this pandemic.

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.

Efficacy of chloroquine and hydroxychloroquine in the treatment of COVID-19.

OBJECTIVE: The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), also called COVID-19, has caused a pandemic which has swiftly involved the entire world and raised great public health concerns. The scientific community is actively exploring treatments that would potentially be effective in combating COVID-19. Hydroxychloroquine has been demonstrated to limit the replication of SARS-CoV-2 virus in vitro. In malarial pandemic countries, chloroquine is widely used to treat malaria. In malarial non-pandemic nations, chloroquine is not widely used. Chloroquine and hydroxychloroquine share similar chemical structures and mechanisms of action. The aim of this study was to indirectly investigate the efficacy of chloroquine and hydroxychloroquine for the treatment of COVID-19 by determining the prevalence of COVID-19 in malaria pandemic and non-pandemic nations. We sought evidence to support or refute the hypothesis that these drugs could show efficacy in the treatment of COVID-19. MATERIALS AND METHODS: We reviewed in vitro studies, in vivo studies, original studies, clinical trials, and consensus reports, that were conducted to evaluate the antiviral activities of chloroquine and hydroxychloroquine. The studies on "COVID-19 and its allied treatment were found from World Health Organization (WHO), ISI-Web of Science, PubMed, EMBASE, Scopus, Google Scholar, and clinical trial registries. The search was based on keywords: antiviral drugs, chloroquine, hydroxychloroquine, COVID-19, COVID-19 treatment modalities, and coronavirus. In addition, we analyzed the prevalence of COVID-19 in malaria pandemic and non-pandemic countries. The review and analyses were performed on March 28, 2020. RESULTS: For this study, we identified a total of 09 published articles: 03 clinical trials with sample size 150; 03 in vitro studies and 03 expert consensus reports. These studies were all suggestive that chloroquine and hydroxychloroquine can successfully treat COVID-19 infections. We found that COVID-19 infections are highly pandemic in countries where malaria is least pandemic and are least pandemic in nations where malaria is highly pandemic. CONCLUSIONS: Chloroquine and hydroxychloroquine have antiviral characteristics in vitro. The findings support the hypothesis that these drugs have efficacy in the treatment of COVID-19. People are currently using these drugs for malaria. It is reasonable, given the hypothetical benefit of these two drugs, that they are now being tested in clinical trials to assess their effectiveness to combat this global health crisis.