Understanding the transmission dynamics and the severity of the novel coronavirus disease 2019 (COVID-19) informs public health interventions, surveillance, and planning. Two important parameters, the basic reproduction number (R0) and case fatality rate (CFR) of COVID-19, help in this understanding process. The objective of this study was to estimate the R0 and CFR of COVID-19 and assess whether the parameters vary in different regions of the world. We carried out a systematic review to retrieve the published estimates of the R0 and the CFR in articles from international databases between 1st January and 31st August 2020. Random-effect models and Forest plots were implemented to evaluate the mean effect size of the R0 and the CFR. Furthermore, the R0 and CFR of the studies were quantified based on geographic location, the tests/thousand population, and the median population age of the countries where studies were conducted. The I2 statistic and the Cochran's Q test were applied to assess statistical heterogeneity among the selected studies. Forty-five studies involving R0 and thirty-four studies involving CFR were included. The pooled estimation of the R0 was 2.69 (95% CI: 2.40, 2.98), and that of the CFR was 2.67 (2.25, 3.13). The CFR in different regions of the world varied significantly, from 2.51 (2.12, 2.95) in Asia to 7.11 (6.38, 7.91) in Africa. We observed higher mean CFR values for the countries with lower tests (3.15 vs. 2.16) and greater median population age (3.13 vs. 2.27). However, the R0 did not vary significantly in different regions of the world. An R0 of 2.69 and CFR of 2.67 indicate the severity of the COVID-19. Although R0 and CFR may vary over time, space, and demographics, we recommend considering these figures in control and prevention measures.

Background and aims Realizing the transmission potential and the magnitude of the coronavirus disease 2019 (COVID‐19) aids public health monitoring, strategies, and preparation. Two fundamental parameters, the basic reproduction number ( R 0 ) and case fatality rate (CFR) of COVID‐19, help in this understanding process. The objective of this study was to estimate the R 0 and CFR of COVID‐19 and assess whether the parameters vary in different regions of the world. Methods We carried out a systematic review to find the reported estimates of the R 0 and the CFR in articles from international databases between January 1 and August 31, 2020. Random‐effect models and Forest plots were implemented to evaluate the mean effect size of R 0 and the CFR. Furthermore, R 0 and CFR of the studies were quantified based on geographic location, the tests/thousand population, and the median population age of the countries where the studies were conducted. To assess statistical heterogeneity among the selected articles, the I 2 statistic and the Cochran's Q test were used. Results Forty‐five studies involving R 0 and 34 studies involving CFR were included. The pooled estimation of R 0 was 2.69 (95% CI: 2.40, 2.98), and that of the CFR was 2.67 (2.25, 3.13). The CFR in different regions of the world varied significantly, from 2.49 (2.08, 2.94) in Asia to 3.40 (2.81, 4.04) in North America. We observed higher mean CFR values for the countries with lower tests (3.15 vs 2.16) and greater median population age (3.13 vs 2.27). However, R 0 did not vary significantly in different regions of the world. Conclusions An R 0 of 2.69 and a CFR of 2.67 indicate the severity of the COVID‐19. Although R 0 and CFR may vary over time, space, and demographics, we recommend considering these figures in control and prevention measures.

In developing countries, acute respiratory infections (ARIs) cause a significant number of deaths among children. According to Bangladesh Demographic and Health Survey (BDHS), about 25% of the deaths in children under-five years are caused by ARI in Bangladesh every year. Low-income families frequently rely on wood, coal, and animal excrement for cooking. However, it is unclear whether using alternative fuels offers a health benefit over solid fuels. To clear this doubt, we conducted a study to investigate the effects of fuel usage on ARI in children. In this study, we used the latest BDHS 2017–18 survey data collected by the Government of Bangladesh (GoB) and estimated the effects of fuel use on ARI by constructing multivariable logistic regression models. From the analysis, we found that the crude (the only type of fuel in the model) odds ratio (OR) for ARI is 1.69 [95% confidence interval (CI): 1.06–2.71]. This suggests that children in families using contaminated fuels are 69.3% more likely to experience an ARI episode than children in households using clean fuels. After adjusting for cooking fuel, type of roof material, child's age (months), and sex of the child–the effect of solid fuels is similar to the adjusted odds ratio (AOR) for ARI (OR: 1.69, 95% CI: 1.05–2.72). This implies that an ARI occurrence is 69.2% more likely when compared to the effect of clean fuel. This study found a statistically significant association between solid fuel consumption and the occurrence of ARI in children in households. The correlation between indoor air pollution and clinical parameters of ARI requires further investigation. Our findings will also help other researchers and policymakers to take comprehensive actions by considering fuel type as a risk factor as well as taking proper steps to solve this issue.

The crude case fatality rate (CFR), because of the calculation method, is the most accurate when the pandemic is over since there is a possibility of the delay between disease onset and outcome. Adjusted crude CFR measures can better explain the pandemic situation by improving the CFR estimation. However, no study has thoroughly investigated the COVID-19 adjusted CFR of the SAARC countries. This study estimated both survival interval and underreporting adjusted CFR of COVID-19 for these countries. Moreover, we assessed the crude CFR between genders and across age groups and observed the CFR changes due to the imposition of fees on COVID-19 tests in Bangladesh. Using the daily records up to October 9, we implemented a statistical method to remove the delay between disease onset and outcome bias, and due to asymptomatic or mild symptomatic cases, reporting rates lower than 50% (95% CI: 10%–50%) bias in crude CFR. We found that Afghanistan had the highest CFR, followed by Pakistan, India, Bangladesh, Nepal, Maldives, and Sri Lanka. Our estimated crude CFR varied from 3.708% to 0.290%, survival interval adjusted CFR varied from 3.767% to 0.296% and further underreporting adjusted CFR varied from 1.096% to 0.083%. Furthermore, the crude CFRs for men were significantly higher than that of women in Afghanistan (4.034% vs. 2.992%) and Bangladesh (1.739% vs. 1.337%) whereas the opposite was observed in Maldives (0.284% vs. 0.390%), Nepal (0.006% vs. 0.007%), and Pakistan (2.057% vs. 2.080%). Besides, older age groups had higher risks of death. Moreover, crude CFR increased from 1.261% to 1.572% after imposing the COVID-19 test fees in Bangladesh. Therefore, the authorities of countries with higher CFR should be looking for strategic counsel from the countries with lower CFR to equip themselves with the necessary knowledge to combat the pandemic. Moreover, caution is needed to report the CFR.

Background Functional difficulties in children can be transmitted from mother to child, which is a major concern. We sought to determine whether there was a correlation between a mother's functional difficulty and functional difficulty in kids between the ages of 2–4 and 5–17. We also want to evaluate other fundamental aspects that influence on child's functionality. Methods We used Multiple Indicator Cluster Survey (MICS) data sets. For two different age groups, the children's difficulty status was evaluated. The sociodemographic factors served as explanatory variables in this study. We used χ 2 tests and survey logistic regression models to analyze the data. Results Functional difficulties were less common in children aged 2–4 years (2.78%) but 8.27% in those aged 5–17 years. The study specifies that the mother's functional difficulty (odds ratio [OR]: 2.66, confidence interval [CI]: 1.35–5.24 for children aged 2–4 years and OR: 3.36, CI: 2.80–4.03 for children aged 5–17 years) were significantly associated with the functional difficulty of both age groups' children. Not attending early childhood education programs (OR: 1.89, CI: 1.16–3.10 for children aged 2–4 years and OR: 2.66, CI: 2.19–3.22 for children aged 5–17 years) and divisions were also significantly affecting the functional difficulty of both age groups' children. Moreover, area of residence and gender were significant factors for the older age group. Conclusions The prevalence of difficulty among children in Bangladesh is high. Children's functional difficulty, regardless of age, is greatly influenced by the functional difficulty of their mothers, their absence from early childhood education programs, and divisions. Reducing the prevalence of child functioning difficulties will be more successful if the government and NGOs consider these factors while developing appropriate intervention programs.