Severity of COVID-19 infection in vaccinated and unvaccinated patients and their outcome - a local experience
DOI:
https://doi.org/10.61529/idjp.v33i4.267Abstract
Background: The COVID-19 pandemic continues to pose a significant global health threat. In late 2020 and early 2021, multiple vaccines were authorized for emergency use, enabling mass vaccination campaigns. This study aimed to evaluate factors influencing COVID-19 severity (mild, moderate, severe) and outcomes (death or discharge) in vaccinated individuals presenting to a tertiary care hospital.
Material and Methods: An observational study was conducted at Dr. Ziauddin Hospital Clifton, Karachi, Pakistan, from June to September 2021. We included patients aged 16 and above with RT-PCR-confirmed COVID-19 infection, categorized by vaccination status (unvaccinated, partially or fully vaccinated). The study analyzed variables such as age, gender, vaccination status, vaccine type, disease severity, day of presentation, hospital stay, and breakthrough infection duration. Data were analyzed using chi-square tests. A total of 341 patients were enrolled, with 219 vaccinated (V1) and 73 unvaccinated (V2).
Results: The median age was 65 years, with 61% males. Among the patients, 45% were fully vaccinated, 13.2% partially vaccinated, and 41% unvaccinated. Disease severity was mild in 17.9%, moderate in 50.1%, and severe in 32%. Disease severity was significantly associated with age (p=0.01), vaccination status (p=0.00), and vaccine type (p=0.00). Time since the last vaccination also influenced breakthrough infections (p=0.00). Of the patients, 76.5% survived and 23.5% died. Disease outcomes were associated with age (p=0.02), severity (p=0.00), hospital stay (p=0.01), and vaccine type (p=0.01).
Conclusion: Age and vaccine-related factors significantly influence disease severity, while additional factors beyond vaccination may impact disease outcomes. Further research is needed to explore these variables.
Keywords: Vaccination, COVID-19, Severity, Immunization, SARS-CoV-2
References
Li M, Liu Q, Wu D, Tang L, Wang X, Yan T, et al. Association of COVID-19 vaccination and clinical severity of patients infected with Delta or Omicron variants—China, May 21, 2021–February 28, 2022. China CDC Wkly. 2022; 4(14): 293-7. DOI: https://doi.org/10.46234/ccdcw2022.074
Attaway AH, Scheraga RG, Bhimraj A, Biehl M, Hatipoğlu U. Severe COVID-19 pneumonia: pathogenesis and clinical management. BMJ. 2021; 372: n436. DOI: https://doi.org/10.1136/bmj.n436
Formica N, Mallory R, Albert G, Robinson M, Plested JS, Cho I, et al. Different dose regimens of a SARS-CoV-2 recombinant spike protein vaccine (NVX-CoV2373) in younger and older adults: A phase 2 randomized placebo-controlled trial. PLoS Med. 2021; 18(10): e1003769. DOI: https://doi.org/10.1371/journal.pmed.1003769
Vardavas CI, Nikitara K, Aslanoglou K, Hilton-Boon M, Phalkey R, Leonardi-Bee J, et al. Effectiveness of non-pharmaceutical measures (NPIs) on COVID-19 in Europe: A systematic literature review. medRxiv. 2021.
DOI: https://doi.org/10.1101/2021.11.11.21266216
Cowling BJ, Ali ST, Ng TW, Tsang TK, Li JC, Fong MW, et al. Impact assessment of non-pharmaceutical interventions against coronavirus disease 2019 and influenza in Hong Kong: An observational study. Lancet Pubic Health. 2020; 5(5): e279-88. DOI: https://doi.org/10.1016/s2468-2667(20)30090-6
Mathieu E, Ritchie H, Ortiz-Ospina E, Roser M, Hasell J, Appel C, et al. A global database of COVID-19 vaccinations. Nat Hum Behav. 2021; 5(7): 947-53. DOI: https://doi.org/10.1038/s41562-021-01122-8
Menni C, Klaser K, May A, Polidori L, Capdevila J, Louca P, et al. Vaccine side-effects and SARS-CoV-2 infection after vaccination in users of the COVID symptom study app in the UK: A prospective observational study. Lancet Infect Dis. 2021; 21(7): 939-49. DOI: https://doi.org/10.1016/s1473-3099(21)00224-3
Bernal JL, Andrews N, Gower C, Robertson C, Stowe J, Tessier E, et al. Effectiveness of the Pfizer-BioNTech and Oxford-AstraZeneca vaccines on COVID-19-related symptoms, hospital admissions, and mortality in older adults in England: A test-negative case-control study. BMJ. 2021; 373: n1088. DOI: https://doi.org/10.1136/bmj.n1088
Haas EJ, Angulo FJ, McLaughlin JM, Anis E, Singer SR, Khan F, et al. Impact and effectiveness of mRNA BNT162b2 vaccine against SARS-CoV-2 infections and COVID-19 cases, hospitalisations, and deaths following a nationwide vaccination campaign in Israel: An observational study using national surveillance data. Lancet. 2021; 397(10287): 1819-29. DOI: https://doi.org/10.1016/s0140-6736(21)00947-8
Singh C, Naik BN, Pandey S, Biswas B, Pati BK, Verma M, et al. Effectiveness of COVID-19 vaccine in preventing infection and disease severity: A case-control study from an Eastern State of India. Epidemiol Infect. 2021; 149: e224.
DOI: https://doi.org/10.1017/s0950268821002247
Sanders RW, de Jong MD. Pandemic moves and countermoves: vaccines and viral variants. Lancet. 2021; 397(10282): 1326-7. DOI: https://doi.org/10.1016/s0140-6736(21)00730-3
Thompson MG, Burgess JL, Naleway AL, Tyner H, Yoon SK, Meece J, et al. Prevention and attenuation of COVID-19 with the BNT162b2 and mRNA-1273 vaccines. N Engl J Med. 2021; 385(4): 320-9. DOI: https://doi.org/10.1056/nejmoa2107058
Wu J, Liu J, Zhao X, Liu C, Wang W, Wang D, et al. Clinical characteristics of imported cases of COVID-19 in Jiangsu province: A multicenter descriptive study. Clin Infect Dis. 2020. DOI: https://doi.org/10.1093/cid/ciaa199
Hashim A. Pakistan received the first COVID-19 vaccine shipment from China [Internet]. Al Jazeera; 2021 [cited 2022 Oct 28]. Available from: https://www.aljazeera.com/news/2021/2/1/pakistan-receives-first-shipment-of-coronavirus-vaccine
Shahzad A. Pakistan launches COVID-19 vaccination drive, starting with elderly [Internet]. Reuters; 2021 [cited 2022 Oct 28]. Available from: https://www.reuters.com/article/us-health-coronavirus-pakistan-vaccine-idUSKBN2B219K
Centers for Disease Control and Prevention. COVID-19 breakthrough case investigations and reporting [Internet]. CDC; 2021 [cited 2022 Oct 28]. Available from: https://www.cdc.gov/vaccines/covid19/health-departments/breakthrough-cases.html
Fabiani M, Mateo-Urdiales A, Sacco C, Rota MC, Petrone D, Bressi M, et al. Relative effectiveness of a 2nd booster dose of COVID-19 mRNA vaccine up to four months post administration in individuals aged 80 years or more in Italy: A retrospective matched cohort study. Vaccine. 2023; 41(1): 76-84. DOI: https://doi.org/10.1016/j.vaccine.2022.11.013
Arregocés-Castillo L, Fernández-Niño J, Rojas-Botero M, Palacios-Clavijo A, Galvis-Pedraza M, Rincón-Medrano L, et al. Effectiveness of COVID-19 vaccines in older adults in Colombia: A retrospective, population-based study of the ESPERANZA cohort. Lancet Healthy Longev. 2022; 3(4): e242-52. DOI: https://doi.org/10.1016/s2666-7568(22)00035-6
Ranzani OT, Hitchings MD, Dorion M, D’Agostini TL, de Paula RC, de Paula OF, et al. Effectiveness of the CoronaVac vaccine in older adults during a Gamma variant-associated epidemic of COVID-19 in Brazil: A test-negative case-control study. BMJ. 2021; 374: n2015. DOI: https://doi.org/10.1136/bmj.n2015
Li Y, Tenchov R, Smoot J, Liu C, Watkins S, Zhou Q. A comprehensive review of the global efforts on COVID-19 vaccine development. ACS Cent Sci. 2021; 7(4): 512-33. DOI: https://doi.org/10.1021/acscentsci.1c00120
Crasto DAM. BBIBP-CorV, Sinopharm COVID-19 vaccine. Greenfield C. 2021.
Muhammad SZ, Shaikh N, Asad D, Fatima N. Challenges to mass immunization against COVID-19 in Pakistan: A lower-middle-income vaccine-hesitant country. J Glob Health. 2022; 12: 03006. DOI: https://doi.org/10.7189/jogh.12.03006
Zayed NE, Abbas A, Lutfy SM. Criteria and potential predictors of severity in patients with COVID-19. Egypt J Bronchol. 2022; 16(1): 11. DOI: https://doi.org/10.1186/s43168-022-00116-y
Matta S, Chopra KK, Arora VK. Morbidity and mortality trends of COVID-19 in top 10 countries. Indian J Tuberc. 2020; 67(4): S167-72. DOI: https://doi.org/10.1016/j.ijtb.2020.09.031
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