Case-fatality rate of SARS-CoV-2 infection during the third and fifth epidemic waves in Spain: Impact of vaccination.

INTRODUCTION: During the first and second epidemic waves in Spain, the SARS-CoV-2 case-fatality rates (CFRs) showed significant differences between Autonomous Communities (ACs). Comparing CFRs in the third and fifth epidemic waves can provide information on the impact of the different vaccination coverages in the ACs. OBJECTIVE: To evaluate the impact of vaccination on COVID-19 CFRs in the third and fifth epidemic waves in Spain, according to sex, age, and AC. METHODS: This work is an observational, descriptive study which uses data on COVID-19 infections, deaths, and vaccinees published by the Spanish Ministry of Health and the regional Health Departments of the ACs. The third epidemic wave was defined as the period from 26th December 2020 to 19th April 2021, and the fifth wave, from 19th July to 19th September 2021. The CFRs (deaths per 1000 infected [‰]) were calculated according to sex, age group, and AC. The standardized case-fatality ratio (SCFR) was adjusted for age and sex for each wave. We estimated the correlation between CFRs and their change between the two epidemic waves with the vaccination coverages reached at the beginning of the fifth wave. RESULTS: The CFR in the fifth wave (5.7‰) was lower than in the third wave (16.5‰). In addition, the CFR in both waves was significantly higher in men than in women, and in older people than in younger ones. A decrease in the CFR between both waves was only observed in those older than 49. A strong direct and positive correlation (R2a=0.8399) was found between vaccination coverage by age group and decrease in CFR between both epidemic waves. Significant differences were seen between ACs in the two waves, as regards both CFRs and SCFRs. When comparing ACs, a direct correlation was observed between vaccination coverage and CFRs in the fifth wave, and also - although weak - between vaccination coverage and decrease in CFR between both waves. CONCLUSION: The CFR significantly decreased in Spain between the third and the fifth epidemic waves in population aged 50 or older, probably due to the high vaccination coverage in that age group. Differences were observed between CFRs and SCFRs between ACs that are not explained by the differences in vaccination coverage, suggesting the need for further research and evaluation.

[Case-fatality rates of SARS-CoV-2 infection according to Autonomous Communities during the second epidemic wave in Spain]. / Tasas de letalidad por SARS-CoV-2 según Comunidades Autónomas durante la segunda onda epidémica en España.

INTRODUCTION: In Spain, health systems are transferred to the Autonomous Communities (AC), constituting 19 health systems with differentiated management and resources. During the first epidemic wave of COVID-19, differences were observed in reporting systems and in case-fatality rates (FR) between the AC. The objective of this study was to analyze the FR according to AC. during the 2 nd epidemic wave (from July 20 to December 25, 2020), and its relationship with the prevalence of infection. MATERIAL AND METHODS: A descriptive observational study was carried out, extracting the information available on the number of deaths from COVID-19 registered in the Ministry of Health, the Health Councils and the Public Health Departments of the AC, and according to the excess mortality reported by the System Monitoring of Daily Mortality (MoMo). The prevalence of infection was estimated from the differences between the second and fourth rounds of the ENE-COVID study and their 95% confidence intervals. The global FR (deaths per thousand infected) were calculated according to sex, age groups (< 65 and ≥ 65 years) and AC. The age-Standardized Fatality Rates (SFR) of the AC were calculated using the FR of Spain for each age group. These estimates were made with officially declared deaths (FRo) and excess deaths estimated by MoMo (FRMo). The correlations between the prevalences of infection and the FRo and FRMo were estimated, weighting by population. RESULTS: For the whole of Spain, the FRo during the second epidemic wave was 7.6%, oscillating between 3.8% in the Balearic Islands and 16.4% in Asturias, and the TLMo was 10.1%, oscillating between 4.8% from Madrid and 21.7% in Asturias. Significant differences were observed between the FRo and the FRMo in the Canary Islands, Castilla la Mancha, Extremadura, the Valencian Community, Andalusia and the Autonomous Cities of Ceuta and Melilla. The FRo was significantly higher in men (8.2%) than in women (7.1%). The FRo and FRMo were significantly higher in the age group ≥ 65 years (55.4% and 72.2% respectively) than in the group <65 years (0.5% and 1.4% respectively). The Basque Country, Aragon, Andalusia and Castilla la Mancha presented SFR significantly higher than the global FR of Spain. The correlations between the prevalence of infection and the FRo were inverse. CONCLUSIONS: The case-fatality from COVID-19 during the second epidemic wave in Spain improved compared to the first wave. The case-fatality rates were higher in men and the elderly people, and varied significantly between AC. It is necessary to delve into the analysis of the causes of these differences.

[Application of the PCR number of cycle threshold value (Ct) in COVID-19]. / Aplicación del valor umbral del número de ciclos (Ct) de PCR en la COVID-19.

The SARS-CoV-2 pandemic persists with all its virulence despite 650,382,819 doses of COVID vaccine worldwide. The reference test for infection identification is reverse transcription polymerase chain reaction (RT-qPCR). The usefulness of this test may be diminished by simplifying its result as positive or negative. Determining the number of cycles (Ct) in positive RT-qPCR tests can assist in decision-making when interpreted in the clinical context of patients.

[Analysis of fatality rates case of SARS-CoV-2 infection in the Autonomous Communities of Spain]. / Análisis de las tasas de letalidad de la infección por SARS-CoV-2 en las comunidades autónomas de España.

INTRODUCTION: The SARS-CoV-2 pandemic has posed a real challenge to health systems. In Spain, the heterogeneous distribution of the virus infection and the different health strategies have conditioned the morbidity and fatality rate. The aim of this study was to analyse the lethality of the infection by sex and age range in the Autonomous Communities (AC) of Spain. MATERIAL AND METHODS: To perform the analysis, data were extracted from the Ministry of Health, Regional and Public Health Departments of the different AC. The infected population was estimated from the results of the ENE-COVID19 and the population registered on 1 January 2020 (INE) for the validity of the IgG antibody test with 80% sensitivity and 100% specificity. The case fatality rate (TL) (deaths/1000 estimated infected) by sex and age (<20years, 20-64 and ≥65years) was calculated for each AC. The standardized case fatality ratio (REL) was calculated by the exact method (EPIDAT). RESULTS: The estimated prevalence of SARS-CoV-2 infection in Spain was 6% (range, 1.4% [Ceuta] -14.1% [Community of Madrid]). The TL in Spain was 9,6/1000, ranged per AC from 1/1000 in Melilla to 26.6/1000 in La Rioja, with no correlation between case fatality and prevalence of infection. The TL was higher in men (10.2/1000, ratio 1.17 with respect to women), except in Cataluña (ratio 0.92), and especially high in those over 64years of age in La Rioja (143.5/1000), Asturias (69.2/1000) and Basque Country (46.6/1000). Overall excess REL was found to be over 30% in La Rioja (2.91; 95%CI: 2.36-3.57), Asturias (1.51; 95%CI: 1.27-1.80), Basque Country (1.42; 95%CI: 1.31-1.54) and Extremadura (1.37; 95%CI: 1.20-1.57) and in those over 64 years in Madrid and the Canary Islands. CONCLUSIONS: SARs-CoV-2 virus infection has been very unevenly distributed in the different ACs, with notably differences in TL between ACs, particularly high in La Rioja, Asturias and the Basque Country. Is important to study the excess in TL the population over 64years of age in the ACs of Madrid and the Canary Islands.

COVID-19. La historia se repite y seguimos tropezando con la misma piedra COVID-19 mortality and health-care resources: Organization

The COVID-19 pandemic has caused a mismatch in all health systems. Most countries had forgotten how to behave in the face of such an epidemic without adequate resources. We need to take stock of everything that has happened, instruct the population and generate a new knowledge that allows us to face new epidemics.

[COVID-19. History repeats itself and we keep stumbling on the same stone]. / COVID-19. La historia se repite y seguimos tropezando con la misma piedra.

The COVID-19 pandemic has caused a mismatch in all health systems. Most countries had forgotten how to behave in the face of such an epidemic without adequate resources. We need to take stock of everything that has happened, instruct the population and generate a new knowledge that allows us to face new epidemics.