From spike to swab: how is COVID-19 detected?

Authors

  • Blanca Ortiz-Quintero Instituto Nacional de Enfermedades Respiratorias Ismael Cosío Villegas, Departamento de Biomedicina Molecular e Investigación Traslacional, Ciudad de México, México https://orcid.org/0000-0001-6298-0073

DOI:

https://doi.org/10.22201/ceide.16076079e.2025.26.3.12

Keywords:

tests, covid-19, diagnosis, virus, sars-CoV-2, pandemic

Abstract

Fatigue, fever, cough, diarrhea, loss of smell, among other combined or isolated symptoms… How can we know if we have covid-19? The only way to answer this question is by performing a diagnostic test that detects the presence of the virus that causes covid-19, sars-CoV-2. There are different types of tests available on the market; so, which one should we choose? This article describes the available types of tests, their characteristics, what they detect, from which part of the body the sample is taken, in which cases they are indicated, and what their results mean. To clearly understand this, the article includes a simplified description of the identity of sars-CoV-2, how it infects, and the timeline of symptom appearance.

Author Biography

Blanca Ortiz-Quintero, Instituto Nacional de Enfermedades Respiratorias Ismael Cosío Villegas, Departamento de Biomedicina Molecular e Investigación Traslacional, Ciudad de México, México

Investigadora en Ciencias Médicas “E”, actualmente se desempeña como titular del Departamento de Biomedicina Molecular e Investigación Traslacional en el Instituto Nacional de Enfermedades Respiratorias Ismael Cosío Villegas ( iner), en la Ciudad de México. Es integrante del Sistema Nacional de Investigadores con nivel ii. Es doctora en Ciencias Biomédicas por la Facultad de Medicina de la unam, y cuenta con una maestría en Ciencias con especialidad en Inmunología, así como una licenciatura como Químico Bacteriólogo y Parasitólogo, ambas por la Escuela Nacional de Ciencias Biológicas del Instituto Politécnico Nacional. Su trayectoria científica se ha centrado en el estudio de los mecanismos de regulación genética y post-transcripcional asociados al proceso neoplásico, la progresión y la metástasis de neoplasias pulmonares.

References

Chvatal-Medina, M., Mendez-Cortina, Y., Patino, P. J., Velilla, P. A., y Rugeles, M. T. (2021). Antibody Responses in covid-19: A Review. Front Immunol, 12, 633184. https://doi.org/10.3389/fimmu.2021.633184

da Silva Torres, M. K., Bichara, C. D. A., de Almeida, M., Vallinoto, M. C., Queiroz, M. A. F., Vallinoto, I., Freitas Queiroz, M. A., Cayres Vallinoto, I. M. V., Melo dos Santos, E. J., Marques de Carvalho, C. A., Vallinoto, A. C. R. (2022). The Complexity of sars-CoV-2 Infection and the covid-19 Pandemic. Front Microbiol, 13, 789882. https://doi.org/10.3389/fmicb.2022.789882

Hayden, M. K., El Mikati, I. K., Hanson, K. E., Englund, J. A., Humphries, R. M., Lee, F., Loeb, M., Morgan, D. J., Patel, R., Al Ta’ani, O., Nazzal, J., Iqneibi, S., Amarin, J. Z. Sultan, S., Falck-Ytter, Y., Morgan, R. L., Hassan Murad, M., Bhimraj, A., Mustafa, R. A. (2024). Infectious Diseases Society of America Guidelines on the Diagnosis of covid-19: Serologic Testing. Clinical Infectious Diseases, ciae121. https://doi.org/10.1093/cid/ciae121

He, X., Lau, E. H. Y., Wu, P., Deng, X., Wang, J., Hao, X., Chung Lau, Y., Wong, J. Y., Guan, Y., Tan, X., Mo, X., Chen, Y., Liao, B., Chen, W., Hu, F., Zhang, Q., Zhong, M., Wu, Y., Zhao, L., … Leung, G. M. (2020). Temporal dynamics in viral shedding and transmissibility of covid-19. Nature Medicine, 26(5), 672-675. https://doi.org/10.1038/s41591-020-0869-5

Hu, B., Guo, H., Zhou, P., y Shi, Z. L. (2021). Characteristics of sars-CoV-2 and covid-19. Nat Rev Microbiol, 19(3), 141-154. https://doi.org/10.1038/s41579-020-00459-7

Kundu, D., Gautam, P., Dayanand, D., Gunasekaran, K., Manesh, A., Sebastian, M., Abhilash, K. P. P., Zachariah, A., George, T., Sathyendra, S., Hansdak, S. G., Abraham, o. C., Iyadurai, R., Thangakunam, B., Gupta, R., Karthik, R., Moorthy, M., Varghese, G. M. (2022). The role and diagnostic accuracy of serology for covid-19. bmc Infect Dis, 22, 390. https://doi.org/10.1186/s12879-022-07361-y

Lapuente, D., Winkler, T. H., y Tenbusch, M. (2024). B-cell and antibody responses to sars-CoV-2: infection, vaccination, and hybrid immunity. Cell Mol Immunol, 21(2), 144-158. https://doi.org/10.1038/s41423-023-01095-w

Mina, M. J., Parker, R., y Larremore, D. B. (2020). Rethinking Covid-19 Test Sensitivity – A Strategy for Containment. New England Journal of Medicine, 383(22), e120. https://doi.org/10.1056/NEJMp2025631

Post, N., Eddy, D., Huntley, C., van Schalkwyk, M. C. I., Shrotri, M., Leeman, D., Rigby, S., Williams, S. V., Bermingham, W. H., Kellam, P., Maher, J., Shields, A. M., Amirthalingam, G., Peacock, S. J., Ismail, S. A. (2020). Antibody response to sars-CoV-2 infection in humans: A systematic review. PLoS One, 15(12), e0244126. https://doi.org/10.1371/journal.pone.0244126

Puhach, O., Meyer, B., y Eckerle, I. (2023). sars-CoV-2 viral load and shedding kinetics. Nat Rev Microbiol, 21(3), 147-161. https://doi.org/10.1038/s41579-022-00822-w

Röltgen, K., y Boyd, S. D. (2024). Antibody and B Cell Responses to sars-CoV-2 Infection and Vaccination: The End of the Beginning. Annu Rev Pathol, 19, 69-97. https://doi.org/10.1146/annurev-pathmechdis-031521-042754

Sabat, J., Subhadra, S., Rath, S., Ho, L. M., Satpathy, T., Pattnaik, D., Pati, S., y Turuk, J. (2023). A comparison of sars-CoV-2 rapid antigen testing with realtime rt-pcr among symptomatic and asymptomatic individuals. bmc Infect Dis, 23, 87. https://doi.org/10.1186/s12879-022-07969-0

Satarker, S., y Nampoothiri, M. (2020). Structural Proteins in Severe Acute Respiratory Syndrome Coronavirus-2. Archives of Medical Research, 51(6), 482-491. https://doi.org/10.1016/j.arcmed.2020.05.012

Sethuraman, N., Jeremiah, S. S., y Ryo, A. (2020). Interpreting Diagnostic Tests for sars-CoV-2. jama, 323(22), 2249-2251. https://dpoi.org/10.1001/jama.2020.8259

Tebha, S. S., Tameezuddin, A., Bajpai, S., y Zaidi, A. K. (2024). sars-CoV-2-Virus structure and life cycle. Prog Mol Biol Transl Sci, 202, 1-23. https://doi.org/10.1016/bs.pmbts.2023.09.001

Zou, L., Ruan, F., Huang, M., Liang, L., Huang, H., Hong, Z., Yu, J., Kang, M., Song, Y., Xia, J., Guo, Q., Song, T., He, J., Yen, H. Peiris, M., Wu, J. (2020). sars-CoV-2 Viral Load in Upper Respiratory Specimens of Infected Patients. New England Journal of Medicine, 382(12), 1177-1179. https://doi.org/10.1056/NEJMc2001737

Published

2025-05-12

Issue

Vol. 26 No. 3 (2025): Del laboratorio a la vida cotidiana: historias que transforman tu día

Section

Varietas

License

Copyright (c) 2025 Revista Digital Universitaria

Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.

Licencia Creative Commons
Revista Digital Universitaria es editada por la Universidad Nacional Autónoma de México se distribuye bajo una Licencia Creative Commons Atribución-NoComercial 4.0 Internacional. Basada en una obra en http://revista.unam.mx/.