Changes in clinical characteristics and outcomes of patients hospitalized with COVID-19 during two years of the pandemic: experience in a venezuelan hospital. / Cambios en las características clínicas y desenlaces de pacientes hospitalizados por COVID-19 durante dos años de pandemia: experiencia en un hospital venezolano.

OBJECTIVES.: To determine changes in the clinical characteristics and in-hospital outcomes of patients hospitalized for COVID-19 in a private hospital in Caracas during two years of the pandemic. MATERIALS AND METHODS.: Retrospective, observational study of patients hospitalized for COVID-19. We evaluated the correspondence between waves of hospital admissions and circulating variants of SARS-CoV-2 in the general population of the Capital District and Miranda state. RESULTS.: A total of 1025 patients (569 men and 456 women) were included, with a mean age of 62.9 SD: 16.2 years. Four waves of hospital admissions were identified: first (March-November 2020) 150/1025 (14.6%) cases; second (December 2020 to May 2021) 415/1025 (40.5%) cases; third (June-December 2021) 344/1025 (33.6%) cases; fourth (January-February 2022) 116/1025 (11.3%) cases. The mean age was higher in the fourth wave (first: 64.0±15.7, second: 61.4±15.8, third: 62.1±16.5, and fourth wave: 68.5±16.4), while the proportion of male patients (first: 66.7%, second: 58.8%, third: 50.3%, and fourth wave: 44.8%), patients with severe-critical illness (first: 65.3%, second: 57%, third: 51.7%, and fourth wave: 44.8%), in-hospital stay (first: 9.1±6.0, second: 9.0±7.3, third: 8.8±7.7, and fourth wave: 6.9±5.0 days), ICU admissions (first: 23.3%, second: 15.7%, third: 14.0%, and fourth wave: 11.2%; p=0.027) and mortality (first: 21. 8%, second: 10.7%, third: 9.1%, and fourth wave: 7.1%; p<0.001) progressively decreased over time. CONCLUSIONS.: The results show lower frequency of severe cases and improvement of in-hospital outcomes in two years of the pandemic. Changes in circulating variants, improvements in disease management and vaccination are likely to have influenced these results.

OBJETIVOS.: Determinar los cambios en las características clínicas y desenlaces intrahospitalarios de los pacientes hospitalizados por COVID-19 en un hospital privado de Caracas durante dos años de pandemia. MATERIALES Y MÉTODOS.: Estudio retrospectivo, observacional, de pacientes hospitalizados por COVID-19. Se investigó la correspondencia entre las olas de ingresos hospitalarios con las variantes circulantes del SARS-CoV-2 en la población general del Distrito Capital y estado Miranda. RESULTADOS.: Se incluyeron 1025 pacientes (569 hombres y 456 mujeres), con edad promedio de 62,9 DE: 16,2 años. Cuatro olas de ingresos hospitalarios fueron identificadas: primera (marzo-noviembre 2020) 150/1025 (14,6%) casos; segunda (diciembre-2020 a mayo-2021) 415/1025 (40,5%) casos; tercera (junio-diciembre 2021) 344/1025 (33,6%) casos; cuarta (enero-febrero 2022) 116/1025 (11,3%) casos. La edad promedio fue mayor en la cuarta ola (primera 64,0±15,7, segunda 61,4±15,8, tercera 62,1±16,5, y cuarta ola 68,5±16,4), mientras que la proporción de pacientes masculinos (primera 66,7%, segunda 58,8%, tercera 50,3%, y cuarta 44,8%), los pacientes con enfermedad grave-crítica (primera 65,3%, segunda 57%, tercera 51,7% y cuarta 44,8%), la estadía intrahospitalaria (primera 9,1±6,0, segunda 9,0±7,3, tercera 8,8±7,7, y cuarta 6,9±5,0 días), los ingresos a la UCI (primera 23,3%, segunda 15,7%, tercera 14,0%, y cuarta 11,2%; p=0,027) y la mortalidad (primera 21.8%, segunda 10,7%, tercera 9,1%, y cuarta 7,1%; p<0,001) disminuyeron progresivamente con el tiempo. CONCLUSIONES.: Los resultados muestran menor frecuencia de casos severos y mejoría de los desenlaces intrahospitalarios en dos años de pandemia. Es probable que los cambios en las variantes circulantes, las mejoras del manejo de la enfermedad y la vacunación hayan influido sobre estos resultados.

Description of a One-Year Succession of Variants of Interest and Concern of SARS-CoV-2 in Venezuela.

Some of the lineages of SARS-CoV-2, the new coronavirus responsible for COVID-19, exhibit higher transmissibility or partial resistance to antibody-mediated neutralization and were designated by WHO as Variants of Interests (VOIs) or Concern (VOCs). The aim of this study was to monitor the dissemination of VOIs and VOCs in Venezuela from March 2021 to February 2022. A 614 nt genomic fragment was sequenced for the detection of some relevant mutations of these variants. Their presence was confirmed by complete genome sequencing, with a correlation higher than 99% between both methodologies. After the introduction of the Gamma VOC since the beginning of the year 2021, the variants Alpha VOC and Lambda VOI were detected as early as March 2021, at a very low frequency. In contrast, the Mu VOI, detected in May 2021, was able to circulate throughout the country. After the detection of the Delta VOC in June 2021, it became the predominant circulating variant. With the arrival of the Omicron VOC in December, this variant was able to displace the Delta one in less than one month.

Detection of the Omicron variant of SARS-CoV-2 in international travelers returning to Venezuela.

BACKGROUND: By the end of 2021, the SARS-CoV-2 Variant of Concern (VOC) Delta was predominant in most of the world. At the end of November, the Omicron variant was first detected in South Africa. This variant was immediately classified as VOC, due to the explosive increase of cases in South Africa, and the great number of mutations exhibited by this new lineage. Since then, Omicron VOC displaced Delta one in almost every country. Venezuela implemented in May 2021 molecular testing of all the passengers arriving at Venezuelan airports. METHODS: In this study, we analyzed the presence of variants of SARS-CoV-2 in those positive samples, by sequencing a small fragment of the Spike genomic region. RESULTS: The Omicron variant was found in passengers arriving to Venezuela from the beginning of December. Complete genome analysis confirmed the presence of the Omicron VOC. The detection of this VOC coincided with an unprecedented increase in the frequency of passengers with positive nucleic acid testing. CONCLUSIONS: Genomic surveillance of samples for international travelers returning to Venezuela allowed us to rapidly detect the introduction of the Omicron variant in the country.

Introduction and rapid dissemination of SARS-CoV-2 Gamma Variant of Concern in Venezuela

In less than two years since SARS-CoV-2 emerged, the new coronavirus responsible for COVID-19, has accumulated a great number of mutations. Many of these mutations are located in the Spike protein and some of them confer to the virus higher transmissibility or partial resistance to antibody mediated neutralization. Viral variants with such confirmed abilities are designated by WHO as Variants of Concern (VOCs). The aim of this study was to monitor the introduction of variants and VOCs in Venezuela. A small fragment of the viral genome was sequenced for the detection of the most relevant mutations found in VOCs. This approach allowed the detection of Gamma VOC. Its presence was confirmed by complete genome sequencing. The Gamma VOC was detected in Venezuela since January 2021, and in March 2021 was predominant in the East and Central side of the country, representing more than 95% of cases sequenced in all the country in April–May 2021. In addition to the Gamma VOC, other isolates carrying the mutation E484K were also detected. The frequency of this mutation has been increasing worldwide, as shown in a survey of sequences carrying E484K mutation in GISAID, and was detected in Venezuela in many probable cases of reinfection. Complete genome sequencing of these cases allowed us to identify E484K mutation in association with Gamma VOC and other lineages. In conclusion, the strategy adopted in this study is suitable for genomic surveillance of variants for countries lacking robust genome sequencing capacities. In the period studied, Gamma VOC seems to have rapidly become the dominant variant throughout the country.