COVID-19 and Immunity
Does infection with coronavirus make you immune to re-infection?
Over 90% of immunocompetent adults develop antibodies to SARS-CoV-2 by day 14 (CID: Mar 2020, PMID 32221519, CID: Apr 2020). But do these antibodies provide protection against re-infection in the future?
We don’t have much longitudinal data for COVID-19 yet. But we can learn a few things from the previous coronaviruses:
1. In one study published in the Journal of Medical Virology (13:179-192, 1984), 18 volunteers were inoculated with one strain of coronavirus in 1977 and developed symptomatic infection. 6 of them were re-challenged a year later with the same strain, and none developed symptomatic infection. The other 12 volunteers were exposed to a slightly different strain of coronavirus a year later, and their protection to that was only partial.
2. Callow et al. (Epidemiol Infect. PMID 2170159) inoculated 15 volunteers with a one strain of coronavirus in 1990. Ten developed symptomatic infection. 14 of these subject were re-inoculated with the same strain a year later. 6 of them became re-infected. However, the period of virus shedding was shorter than before and none developed symptoms.
3. Patients with SARS CoV-1 and MERS have detectable antibodies for several years after illness (Respirology. 2006. PMID: 16423201, EID. 2016. PMID: 27332149)
4. For two seasonal coronaviruses (betacoronaviruses OC43 and HKU1) most closely related to SARS-CoV-2, based on mathematical modeling, immunity lasts for a year or more. (Science. Apr 2020. PMID 32291278).
Based on these observations, I believe that majority (not all) patients with COVID-19 will develop full or partial immunity that would last for at least a year or more. This will also contribute to herd immunity over time and makes me optimistic that vaccines under development, when available, will be helpful.
These are, of course, predictions based on the past behavior of other coronaviruses. However, as great Jedi master Yoda taught us, “Always in motion the future is”.
~ M. Rizwan Sohail MD
Assistant Professor of Medicine
4 年Thanks for the synopsis. What do you think about the new data from Los Alamos regarding mutant strain which is more contagious and has been prevelant in Europe and America? Why is that we don't have vaccines for any of the previous coronaviruses? Is that because it was never attempted or that they mutate at a rate that makes vaccine ineffective?
Cardiovascular Medicine Fellow, University of Nebraska Medical Center |Researcher | Writer | Poet
4 年M. Rizwan Sohail, MD What is your opinion regarding the cases of re-infection in patients who had recovered from COVID-19 in South Korea? Could it be a relapse due to dormant virus or is it re-infection or is it due to discrepancies with testing?