A global analysis of COVID-19 infection fatality rate and its associated factors during the Delta and Omicron variant periods: an ecological study

BackgroundThe Omicron variant of SARS-CoV-2 is more highly infectious and transmissible than prior variants of concern. It was unclear which factors might have contributed to the alteration of COVID-19 cases and deaths during the Delta and Omicron variant periods. This study aimed to compare the COVID-19 average weekly infection fatality rate (AWIFR), investigate factors associated with COVID-19 AWIFR, and explore the factors linked to the increase in COVID-19 AWIFR between two periods of Delta and Omicron variants.Materials and methodsAn ecological study has been conducted among 110 countries over the first 12 weeks during two periods of Delta and Omicron variant dominance using open publicly available datasets. Our analysis included 102 countries in the Delta period and 107 countries in the Omicron period. Linear mixed-effects models and linear regression models were used to explore factors associated with the variation of AWIFR over Delta and Omicron periods.FindingsDuring the Delta period, the lower AWIFR was witnessed in countries with better government effectiveness index [β = −0.762, 95% CI (−1.238)–(−0.287)] and higher proportion of the people fully vaccinated [β = −0.385, 95% CI (−0.629)–(−0.141)]. In contrast, a higher burden of cardiovascular diseases was positively associated with AWIFR (β = 0.517, 95% CI 0.102–0.932). Over the Omicron period, while years lived with disability (YLD) caused by metabolism disorders (β = 0.843, 95% CI 0.486–1.2), the proportion of the population aged older than 65 years (β = 0.737, 95% CI 0.237–1.238) was positively associated with poorer AWIFR, and the high proportion of the population vaccinated with a booster dose [β = −0.321, 95% CI (−0.624)–(−0.018)] was linked with the better outcome. Over two periods of Delta and Omicron, the increase in government effectiveness index was associated with a decrease in AWIFR [β = −0.438, 95% CI (−0.750)–(−0.126)]; whereas, higher death rates caused by diabetes and kidney (β = 0.472, 95% CI 0.089–0.855) and percentage of population aged older than 65 years (β = 0.407, 95% CI 0.013–0.802) were associated with a significant increase in AWIFR.ConclusionThe COVID-19 infection fatality rates were strongly linked with the coverage of vaccination rate, effectiveness of government, and health burden related to chronic diseases. Therefore, proper policies for the improvement of vaccination coverage and support of vulnerable groups could substantially mitigate the burden of COVID-19

Comparison of COVID-19 Resilience Index and Its Associated Factors across 29 Countries during the Delta and Omicron Variant Periods

Our study aims to compare the pandemic resilience index and explore the associated factors during the Delta and Omicron variant periods. In addition, the study aims to identify the characteristics of countries that had good performances. We analyzed observation data among 29 countries over the first eight weeks during the two periods of Delta and Omicron variant dominance. Data were extracted from open public databases. The Omicron variant caused a lowered mortality rate per 100,000 COVID-19 patients; however, it is still imposing a colossal burden on health care systems. We found the percentage of the population fully vaccinated and high government indices were significantly associated with a better resilience index in both the Delta and Omicron periods. In contrast, the higher death rate of cancers and greater years lived with disability (YLD) caused by low bone density were linked with poor resilience index in the Omicron periods. Over two periods of Delta and Omicron, countries with good performance had a lower death rate from chronic diseases and lower YLD caused by nutrition deficiency and PM2.5. Our findings suggest that governments need to keep enhancing the vaccine coverage rates, developing interventions for populations with chronic diseases and nutrition deficiency to mitigate COVID-19 impacts on these targeted vulnerable cohorts

Bio-Kil, a nano-based disinfectant, reduces environmental bacterial burden and multidrug-resistant organisms in intensive care units

Background/Purpose: This prospective before-after study was intended to investigate the effect of Bio-Kil on reducing environmental bacterial burden and healthcare-associated infections (HAIs) in intensive care units (ICUs) at the Municipal Wan-Fang Hospital, Taipei, Taiwan in 2014. Methods: Four rooms in the medical and surgical ICUs were investigated and designated as study rooms (n = 2) or control rooms (n = 2). Routine disinfection was performed during the pre-intervention period in both room types. Bio-Kil was applied to the fomites and surroundings of the study rooms during the intervention period. Total bacterial burden and proportion of colonization of fomites and surroundings by multidrug-resistance organisms (MDROs) were determined before and after the intervention. The demographic characteristics, underlying conditions, and clinical outcomes of patients were analyzed. Results: After application of Bio-Kil, the bacterial burden declined in both groups, although the reduction was greater in the study rooms as compared with the control rooms (p = 0.001). During the pre-intervention period, 16 patients were admitted to control rooms and 18 patients to study rooms. After the intervention, 22 patients were admitted to control rooms and 21 patients to study rooms. The number of cases of new-onset sepsis declined in the intervention group (from 33% to 23.8%), but increased in the control group (from 25% to 40.9%); however, there was no significant difference in incidence of new-onset sepsis between the study and control rooms after intervention. Conclusion: Application of Bio-Kil reduced the environmental bacterial burden and MDROs in ICUs. Further studies are needed to evaluate the efficacy of this nanotechnology-based disinfectant in reducing HAIs

Fluconazole induces rapid high-frequency MTL homozygosis with microbiological polymorphism in Candida albicans

Background: Candida albicans, a common fungal pathogen that can cause opportunistic infections, is regarded as an apparently asexual, diploid fungus. A parasexual cycle was previously found between homozygotes with opposite mating type-like loci (MTLa/α). Fluconazole-resistant strains had a higher proportion of MTL homozygotes, whereas MTL homozygous C. albicans was found in only about 3.2% of clinical strains. MTL heterozygotes had a low frequency (1.4 Ã 10â4) of whiteâopaque switching to MTL homozygotes in nature. Methods: Here, a reference C. albicans strain (SC5314) was used in a fluconazole-induced assay to obtain standard opaque MTL homozygous strains and first-generation daughter strains from the fluconazole inhibition zone. Further separation methods were employed to produce second- and third-generation daughter strains. Polymerase chain reaction analysis based on MTL genes was used to define MTL genotypes, and microscopic observations, a flow-cytometric assay, and an antifungal E-test were used to compare microbiological characteristics. Results: MTL homozygotes were found at a high frequency (17 of 35; 48.6%) in fluconazole-induced first-generation daughter strains, as were morphological polymorphisms, decreased DNA content, and modified antifungal drug susceptibility. High-frequency MTL homozygosity was identified inside the fluconazole inhibition zone within 24 hours. The DNA content of fluconazole-induced daughter strains was reduced compared with their progenitor SC5314 and standard MTL homozygous strains. Conclusion: Treatment with fluconazole, commonly used to treat invasive candidiasis, inhibited the growth of C. albicans and altered its microbiological characteristics. Our results suggest that fluconazole treatment induces the high frequency of loss of heterozygosity and microbiological polymorphism in C. albicans. Keywords: Candida albicans, fluconazole, loss of heterozygosity, mating type-like gen