Background Brain cancer is a rare and deadly malignancy with a low survival rate. The present study aims to evaluate the epidemiology of brain cancer and its relationship with the human development index (HDI) worldwide. Methods This is an ecological study. The data on cancer incidence and cancer mortality was extracted from the World Bank for Cancer in 2018 (GLOBOCAN 2018). The incidence, mortality rate, and brain cancer distribution maps were drawn for different countries. We used correlation and regression tests to examine the association of incidence and mortality rates of brain cancer with HDI. The statistical analysis was carried out by Stata-14 and a significance level of 0.05 was considered. Results According to the results of Global Cancer Registry in 2018, there were 18,078,957 registered cases of cancer in both sexes, of which 29,681 were related to brain cancer. The highest incidence (102,260 cases, 34.4%) and mortality (77,815 cases, 32.3%) belonged to very high HDI regions. Results showed that incidence (r = 0.690, P < 0.0001) and mortality rates (r = 0.629, P < 0.001) of brain cancer are significantly correlated with HDI. We also observed a positive correlation between brain cancer incidence and Gross National Income (GNI) (r = 0.346, P < 0.001), Mean Years of Schooling (MYS) (r = 0.64, P < 0.001), TABLE (LEB) (r = 0.66, P < 0.001) and Expected Years of Schooling (EYS) (r = 0.667, P < 0.001). Results also revealed that mortality rate was significantly correlated with GNI (r = 0.28, P < 0.01), MYS (r = 0.591, P < 0.01), LEB (r = 0.624, P < 0.01), and EYS (r = 0.605, P < 0.01). Conclusion The results of the study showed that the incidence and mortality of brain cancer in countries with higher HDI levels is higher than countries with lower HDI levels, so attention to risk factors and action to reduce it in countries with higher HDI levels in controlling this cancer in this Countries are effective.

Covid-19 has killed more than 7 million people in the world so far. With general vaccination in 2021, the severity of deaths decreased significantly, but after 6 months, new types of Covid-19 emerged and deaths incidence increased. Epidemiological studies showed that despite high number of deaths, vaccination has reduced the severity of the disease in population. Many researchers did not suggest injecting third and fourth doses due to antigenic changes of virus, but some countries, such as Iran, have continued vaccination. In America and European countries, it has been suggested that vaccination should continue only for high-risk people. Biological science has not rejected dangerous mutations for this virus and has prepared itself to face mutated species of this virus again. Certainly, vaccination is the most important way to deal with the virus in future; but despite millions of mutations in Covid-19 virus structure, the compatibility of vaccine with new viral antigens is important in order to provide effective vaccines with high efficiency.

Iran has one of the highest death rates from COVID-19 among Middle Eastern countries. In addition to having a better disease registration system compared to neighboring countries, many factors including economic conditions, have played an important role in increasing the number of mortality rate. This is while that during the Corona pandemic, Iran has been undergo severe sanctions by the United States, that has faced this country with a severe economic crisis. Considering the role of sanction on the country's health management in our study, we examined Iran's management plans against the Corona pandemic and the effect of sanctions on it. Quarantine and corona restrictions, on the one hand, and international sanctions, on the other hand, have put double pressure on the Iranian government. Although drugs and basic medical equipment are exempted from economic sanctions, direct and indirect effects of the sanctions have limited Iran's banking system and created widespread restrictions in the fields of trade, production, and investment. Fortunately, despite the sanctions, many hospitals had an appropriate performance in line with the health promotion program. It is obvious that economic sanctions have severe and harmful effects on public health and have led to poor health consequences in Iran, but attention to planning, standards and improving the quality of the hospital is an important issue in Corona management. Despite multiple mutations, this virus is likely to face with a more dangerous virus in the world future. Now, it is time to take appropriate management measures to remove these sanctions by relying on international solutions and interactions.