Epidemiological and clinical characteristics of influenza in hospitalized patients, Santa Cruz, Bolivia, 2025: a descriptive study
Influenza caracterización clínica epidemiológica Hospital Obrero N°3 Santa Cruz
DOI:
https://doi.org/10.52428/20756208.v20i49.1436Keywords:
Bolivia, Clinic, H1N1, Hospitalization, InfuenzaAbstract
Introduction: Influenza is an acute respiratory disease with high mutation and transmission capacity, associated with seasonal epidemics and pandemics. In Bolivia, the department of Santa Cruz reported an increase in cases in 2025, which led to the declaration of a red alert. The aim of this study is to describe the epidemiological and clinical characteristics of patients hospitalized with influenza at Hospital Obrero No.3 in Santa Cruz, Bolivia. Material and Methods: Observational, descriptive study in patients over 15 years of age hospitalized between January 1 and May 17, 2025, with confirmed influenza diagnosis by reverse transcription polymerase chain reaction (RT-PCR). Sociodemographic and clinical variables, comorbidities, vaccination status, viral subtype, admission to the intensive care unit, and discharge outcome were analyzed. Results: A total of 88 patients were included. Most were over 60 years old (64%) and had comorbidities (86%), mainly hypertension (40%) and diabetes (32%). Only 17% were vaccinated. The most frequent symptoms were cough (100%), fever (97%), and dyspnea (97%). The predominant subtype was A(H1N1) pdm09 (97%). Twenty-five percent required admission to the intensive care unit, and 24% died. Discussion: Severe influenza cases in Santa Cruz were concentrated among older adults with comorbidities, low vaccination coverage, and predominance of the A(H1N1) pdm09 subtype. The findings highlight the need to strengthen vaccination and epidemiological surveillance to reduce the disease burden.
Downloads
References
1. Influenza, SARS-CoV-2, VSR y otros virus respiratorios - OPS/OMS | Organización Panamericana de la Salud [Internet]. 2025 [citado 28 de mayo de 2025]. Disponible en: https://www.paho.org/es/temas/influenza-sars-cov-2-vsr-otros-virus-respiratorios
2. Gripe pandémica: una visión general | Temas de ScienceDirect [Internet]. [citado 29 de septiembre de 2025]. Disponible en: https://www.sciencedirect.com/topics/medicine-and-dentistry/pandemic-influenza
3. Situación de la influenza - Región de las Américas - OPS/OMS | Organización Panamericana de la Salud [Internet]. [citado 4 de noviembre de 2025]. Disponible en: https://www.paho.org/en/topics/influenza-sars-cov-2-rsv-and-other-respiratory-viruses/influenza-situation-region-americas
4. Kokori E, Olatunji G, Mokuolu A, Akinoso A, Olunlade I, Bonu IS, et al. Influenza A(H1N2)v: global impact, emerging threats and preventive measures. Ann Med Surg (Lond) [Internet]. 12 de marzo de 2024 [citado 5 de noviembre de 2025];86(5):2388-90. Disponible en: https://pmc.ncbi.nlm.nih.gov/articles/PMC11060236/ DOI: https://doi.org/10.1097/MS9.0000000000001948
5. Zhang X, Ross TM. Anti-neuraminidase immunity in the combat against influenza. Expert Review of Vaccines [Internet]. 31 de diciembre de 2024 [citado 6 de noviembre de 2025];23(1):474-84. Disponible en: https://www.tandfonline.com/doi/full/10.1080/14760584.2024.2343689 DOI: https://doi.org/10.1080/14760584.2024.2343689
6. Martins AM, Valero Juan LF, Santos M, Martins JP. Immunogenicity as a Predictor of Influenza Vaccine Efficacy: A Systematic Review. Vaccines [Internet]. 14 de agosto de 2025 [citado 6 de noviembre de 2025];13(8):859. Disponible en: https://www.mdpi.com/2076-393X/13/8/859 DOI: https://doi.org/10.3390/vaccines13080859
7. Wang Y, Liu Y, Liu G, Sun X, Zhang Z, Shen J. Analysis of data from two influenza surveillance hospitals in Zhejiang province, China, for the period 2018–2022. Thorrington DL, editor. PLoS ONE [Internet]. 28 de febrero de 2024 [citado 6 de noviembre de 2025];19(2):e0299488. Disponible en: https://dx.plos.org/10.1371/journal.pone.0299488
8. Peng W, Liu H, Wang X, Li C, Huang S, Qi S, et al. Analysis of Epidemiological and Evolutionary Characteristics of Seasonal Influenza Viruses in Shenzhen City from 2018 to 2024. Viruses [Internet]. 30 de mayo de 2025 [citado 6 de noviembre de 2025];17(6):798. Disponible en: https://www.mdpi.com/1999-4915/17/6/798 DOI: https://doi.org/10.3390/v17060798
9. Wang Y, Liu Y, Liu G, Sun X, Zhang Z, Shen J. Analysis of data from two influenza surveillance hospitals in Zhejiang province, China, for the period 2018–2022. Thorrington DL, editor. PLoS ONE [Internet]. 28 de febrero de 2024 [citado 6 de noviembre de 2025];19(2):e0299488. Disponible en: https://dx.plos.org/10.1371/journal.pone.0299488 DOI: https://doi.org/10.1371/journal.pone.0299488
10. Ryu S, Cowling BJ. Human Influenza Epidemiology. Cold Spring Harb Perspect Med [Internet]. diciembre de 2021 [citado 26 de mayo de 2025];11(12):a038356. Disponible en: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8634793/ DOI: https://doi.org/10.1101/cshperspect.a038356
11. Wu H, Xue M, Wu C, Ding Z, Wang X, Fu T, et al. Estimation of influenza incidence and analysis of epidemic characteristics from 2009 to 2022 in Zhejiang Province, China. Front Public Health [Internet]. 18 de mayo de 2023 [citado 6 de noviembre de 2025];11:1154944. Disponible en: https://www.frontiersin.org/articles/10.3389/fpubh.2023.1154944/full DOI: https://doi.org/10.3389/fpubh.2023.1154944
12. Hoyos-Cerón T, Albarrán-Tamayo F, Bañuelos-Hernández B, Londoño-Avendaño MA. Disparities in Influenza Control and Surveillance in Latin America and the Caribbean. Viruses [Internet]. 5 de febrero de 2025 [citado 6 de noviembre de 2025];17(2):225. Disponible en: https://www.mdpi.com/1999-4915/17/2/225 DOI: https://doi.org/10.3390/v17020225
13. Pascale JM, Franco D, Devadiga R, DeAntonio R, Dominguez-Salazar EL, Dos Santos G, et al. Burden of Seasonal Influenza A and B in Panama from 2011 to 2017: An Observational Retrospective Database Study. Infect Dis Ther [Internet]. diciembre de 2021 [citado 6 de noviembre de 2025];10(4):2465-78. Disponible en: https://link.springer.com/10.1007/s40121-021-00501-y DOI: https://doi.org/10.1007/s40121-021-00501-y
14. Costantino C, Mazzucco W, Graziano G, Maida CM, Vitale F, Tramuto F. Mid-Term Estimates of Influenza Vaccine Effectiveness against the A(H1N1)pdm09 Prevalent Circulating Subtype in the 2023/24 Season: Data from the Sicilian RespiVirNet Surveillance System. Vaccines [Internet]. 14 de marzo de 2024 [citado 6 de noviembre de 2025];12(3):305. Disponible en: https://www.mdpi.com/2076-393X/12/3/305 DOI: https://doi.org/10.3390/vaccines12030305
15. Ocho cosas que hay que saber acerca de la gripe pandémica [Internet]. [citado 26 de mayo de 2025]. Disponible en: https://www.who.int/es/news-room/feature-stories/detail/8-things-to-know-about-pandemic-influenza
16. P S, Dhandapani N SK. Evaluation of Pregnancy, Younger Age, and Old Age as Independent Risk Factors for Poor Hospitalization Outcomes in Influenza A (H1N1) pdm09 Virus a Decade After the Pandemic. Cureus [Internet]. 28 de noviembre de 2020 [citado 6 de noviembre de 2025]; Disponible en: https://www.cureus.com/articles/45594-evaluation-of-pregnancy-younger-age-and-old-age-as-independent-risk-factors-for-poor-hospitalization-outcomes-in-influenza-a-h1n1pdm09-virus-a-decade-after-the-pandemic
17. Fu B, Wu Z, Huang L, Chai Z, Zheng P, Sun Q, et al. A comparison of demographic, epidemiological and clinical characteristics of hospital influenza-related viral pneumonia patients. BMC Infect Dis [Internet]. diciembre de 2021 [citado 6 de noviembre de 2025];21(1):1002. Disponible en: https://bmcinfectdis.biomedcentral.com/articles/10.1186/s12879-021-06485-x DOI: https://doi.org/10.1186/s12879-021-06485-x
18. Kniss K, Sumner KM, Tastad KJ, Lewis NM, Jansen L, Julian D, et al. Risk for Infection in Humans after Exposure to Birds Infected with Highly Pathogenic Avian Influenza A(H5N1) Virus, United States, 2022. Emerg Infect Dis [Internet]. junio de 2023 [citado 6 de noviembre de 2025];29(6). Disponible en: https://wwwnc.cdc.gov/eid/article/29/6/23-0103_article DOI: https://doi.org/10.3201/eid2906.230103
19. OMS EMRO - Vigilancia de la gripe [Internet]. [citado 29 de septiembre de 2025]. Disponible en: https://www.emro.who.int/health-topics/influenza/influenza-surveillance.html
20. Ministerio de Salud y Deportes de Bolivia - LOS CASOS DE INFLUENZA BAJAN EN ALMENOS SEIS DEPARTAMENTOS, ESPECIALMENTE EN SANTA CRUZ [Internet]. [citado 27 de mayo de 2025]. Disponible en: https://www.minsalud.gob.bo/8610-los-casos-de-influenza-bajan-en-almenos-seis-departamentos-especialmente-en-santa-cruz
21. Gobernación de Santa Cruz [Internet]. [citado 29 de septiembre de 2025]. Disponible en: https://www.facebook.com/GobSantaCruz/posts/atenci%C3%B3n-santa-cruzante-el-incremento-de-casos-de-influenza-el-departamento-entr/1402375438596874/
22. Vacuna contra la influenza | OPS/OMS | Organización Panamericana de la Salud [Internet]. [citado 28 de mayo de 2025]. Disponible en: https://www.paho.org/es/vacuna-contra-influenza
23. Ministerio de Salud y Deportes de Bolivia - conoce los grupos de riesgo prioritarios para recibir la vacuna contra la influenza. el gobierno ya distribuyó más de 1,5 millones de dosis en todo el país [Internet]. [citado 28 de septiembre de 2025]. Disponible en: https://www.minsalud.gob.bo/8624-conoce-los-grupos-de-riesgo-prioritarios-para-recibir-la-vacuna-contra-la-influenza-el-gobierno-ya-distribuyo-mas-de-1-5-millones-de-dosis-en-todo-el-pais
24. Al-Dorzi HM, Alsafwani ZA, Alsalahi E, Aljulayfi AS, Alshaer R, Alanazi S, et al. Patients with influenza admitted to a tertiary-care hospital in Riyadh between 2018 and 2022: characteristics, outcomes and factors associated with ICU admission and mortality. BMC Pulm Med [Internet]. 19 de septiembre de 2024 [citado 6 de noviembre de 2025];24(1):464. Disponible en: https://bmcpulmmed.biomedcentral.com/articles/10.1186/s12890-024-03281-6 DOI: https://doi.org/10.1186/s12890-024-03281-6
25. Sumner KM, Masalovich S, O’Halloran A, Holstein R, Reingold A, Kirley PD, et al. Severity of influenza-associated hospitalisations by influenza virus type and subtype in the USA, 2010–19: a repeated cross-sectional study. The Lancet Microbe [Internet]. noviembre de 2023 [citado 6 de noviembre de 2025];4(11):e903-12. Disponible en: https://linkinghub.elsevier.com/retrieve/pii/S2666524723001878 DOI: https://doi.org/10.1016/S2666-5247(23)00187-8
26. Hernandez-Solis A, Amaral-Villaseñor D, Balderas-Salazar LA, Velázquez-Gachuz YM, García-Torres ME. Características clínicas y factores de riesgo en pacientes hospitalizados con influenza severa en una unidad de cuidados respiratorios de la CDMX. Salud Pública de México [Internet]. 5 de noviembre de 2024 [citado 28 de mayo de 2025];66(6 (nov-dec)):899-900. Disponible en: https://saludpublica.mx/index.php/spm/article/view/15729 DOI: https://doi.org/10.21149/15729
27. Gómez-Palacios G, Almeida-de La Cruz L, Torres-Erazo D, Quiroz-Zúñiga JL, Núñez-Caamal N, Cortés-Télles A. Caracterización clínica y mortalidad por influenza A(H1N1) en dos centros hospitalarios del sureste de México. HMCM [Internet]. 26 de diciembre de 2023 [citado 28 de mayo de 2025];14(2):11372. Disponible en: https://hospitalmedicineandclinicalmanagement.com/frame_esp.php?id=131 DOI: https://doi.org/10.24875/HMCM.21000002
28. Suárez‐Sánchez P, Majuelos‐Melguizo J, Hinojosa‐Campos M, Podmore B, Gillespie IA, Han J, et al. Mortality Risk Among Patients With Influenza Illness Admitted to the ICU: A Systematic Review and Meta‐Analysis. Influenza Resp Viruses [Internet]. marzo de 2025 [citado 6 de noviembre de 2025];19(3):e70073. Disponible en: https://onlinelibrary.wiley.com/doi/10.1111/irv.70073 DOI: https://doi.org/10.1111/irv.70073
Downloads
Published
How to Cite
Issue
Section
License
Copyright (c) 2025 Daisy Cecilia Ugarte Coronel, Arletta Rocio Añez-Valdez
This work is licensed under a Creative Commons Attribution 4.0 International License.
Authors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License 4.0 that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work.
