The debate on whether or not we can get coronavirus more than once
Even with the current social distancing guidelines intended to stop the spread of the virus, almost half of Americans are projected to contract the highly-contagious novel coronavirus, which causes COVID-19. Even if most people recover from the virus, there is the possibility that the coronavirus could last beyond the months following this pandemic. If people can be reinfected, the illness could become an ongoing or seasonal occurrence, rather than a sporadic one. As of now, scientists have not synthesized a vaccine, and they might never. Thus, health experts are looking at other ways to control the spread of the virus without medically-induced treatments.
When a virus enters the human body, it invades a host cell and spreads to other cells. In response, the immune system, specifically the plasma cells, makes antibodies–––proteins that neutralize the virus and make it incapable of infecting more cells (1). If the virus tries to reinvade the cells, the antibodies can recognize the germs and attack them before they spread throughout the body (2). However, these antibodies may expire, or become ineffective after some time. Take the influenza virus, for example: although the body makes antibodies, you can get the flu more than once because the genes of the virus slightly mutate each year (3). Thus, people have to get the flu vaccine each year to account for the high mutation rates.
Similarly, a study showed that 51 recovered South Korean patients tested positive for the virus again after showing no symptoms (4). In addition, a study on 16 patients from Beijing, China showed that half of the patients tested positive after the disappearance of all symptoms. Despite these patients testing positive, however, the health experts concluded that these test results were due to the presence of remnants of the genetic material of the virus, not the live, infectious virus itself (4).
Theoretically, the body should create antibodies so that people do not re-contract the virus after recovering. However, some studies have found that patients do not develop antibodies at all. In a study of coronavirus antibodies in recovered patients shows, the researchers tested 175 recovered coronavirus patients at Shanghai hospitals. Out of the sample, 10 patients did not have detectable antibodies in their bloodstreams (5). The researchers also observed that elderly and middle-aged patients developed higher levels of traceable antibodies than younger patients.
Even though they found antibodies in most ill and recovered patients, they are still unsure about the amount of time that immunity can last. Antibodies that the body creates for other types of coronaviruses such as SARS and MERS grant immunity for at least a short time (6). For COVID-19, however, scientists lack sufficient research concerning how long recovered patients can stay immune to the virus.
Relying on developing a vaccine would be the most optimal solution to resolving the coronavirus pandemic, but this might not ever happen. Therefore, some have suggested investigating a potentially more effective, but extreme option: herd immunity—waiting for the majority of the population to contract the virus. When a large amount of the population contracts a virus, enough people develop natural immunity to the virus, so that fewer people can transmit it. The emergence of herd immunity helped mitigate the Zika virus in 2015, as after two years, 63 percent of the population of the Brazillian city of Salvador had exposure to the virus. Since so many people had been exposed to the virus, researchers concluded that herd immunity helped diminish the effect of the outbreak (7). However, using herd immunity too quickly could cause complications, as many people would be sick at one time, causing the healthcare system’s capacity to be drastically overfilled.
No definite method exists to treat or stop the spread of the virus. If people can indeed re-contract the coronavirus–––at least within a short time after recovery–––the pandemic could last for a long time with the lack of standard treatments or vaccines. Therefore, with its high contagion rate and long incubation periods, the virus creates challenges that may cause health experts to consider more unconventional options.
– Gerson Personnat
References
- Laing K. Immune responses to viruses. British Society for immunology. Retrieved from https://www.immunology.org/public-information/bitesized-immunology/pathogens-and-disease/immune-responses-viruses.
- Iftikhar, N. (2020, April 2). What is Herd Immunity and Could It Help Prevent COVID-19?. healthline. Retrieved from https://www.healthline.com/health/herd-immunity.
- How the Flu Virus Can Change: “Drift” and “Shift”. Centers for Disease Control and Prevention. Retrieved from https://www.cdc.gov/flu/about/viruses/change.htm.
- Park, K. (2020, April 9). Coronavirus May ‘Reactivate’ in Cured Patients, Korean CDC Says. Bloomberg. Retrieved from https://www.bloomberg.com/news/articles/2020-04-09/coronavirus-may-reactivate-in-cured-patients-korean-cdc-says.
- Secon, H. (2020, April 11). New research raises questions about coronavirus immunity: 6% of recovered patients in one study didn’t develop antibodies at all. Business Insider. Retrieved from https://www.businessinsider.com/study-recovered-coronavirus-patients-antibodies-2020-.
- (2020, April 8). What ‘recovered from coronavirus’ means. PBS News. Retrieved from https://www.pbs.org/newshour/health/what-recovered-from-coronavirus-means.
- Regalado, A. (2020, March 17). What is herd immunity and can it stop the coronavirus? MIT Technology Review.https://www.technologyreview.com/2020/03/17/905244/what-is-herd-immunity-and-can-it-stop-the-coronavirus/.
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