Can COVID 19 Confer Protective Immunity?
As of June 4, 2020, the Coronavirus pandemic has claimed the lives of 388,416, and infected 6,588,761. And while this is a sad milestone, it is also important to realize that research is underway to develop vaccine and effective treatment. Meanwhile, in the absence of vaccine or effective treatment, people are wondering if infection affords immunity. This level of knowledge can help with going back to work, and we can also use the information on antibody response to better understand the current state of the pandemic.
One of the most vexing questions regarding the new coronavirus pandemic relates to the potential for life-long immunity. Since the virus is new, it is hard to understand its pathogenesis, which means there are too many known unknowns and more importantly our body’s response to the infection remains an intense area of research. Indeed, it is the exaggerated response to the virus that causes the damage that sometimes lead to death in a process called “cytokine storm”.
Now, for the COVID-19 immunity, does infection protect us against re-infection? The answer is not clear yet. But based on the evidence that we have so far, once a person is exposed to the virus and makes a successful recovery, it is highly unlikely that they get re-infected at least within the first few months or even years. The evidence for this comes from studies. A study that was done in China and published in nature medicine, they concluded “Within 19 days after symptom onset, 100% of patients tested positive for antiviral immunoglobulin-G (IgG).” They looked at 285 people hospitalized with severe COVID-19 and determined that the patients developed antibodies around 2-3 weeks post infection. Indeed, around 40 percent of the people developed the first part of the antibody called IgM in the first week while more than 90 percent went on develop the same antibody in subsequent weeks.
In summary, studies have shown that people can develop immunity to SARS-COV2 infection. And it takes about about two weeks to develop the immunity (IgM and IgG). And the antibody testing while not perfect is being streamlined for future use.
The bigger question is this: for how long can the immunity protect you? We are not sure as the virus is new (5-6 months). However, based on other viruses and our knowledge of how the immune system works, it is reasonable to assume that an immunity against the SARS-COV2 could last anywhere from a few months to years.
See video for more info:
website: scieheal.com
sources: Long QX, Liu BZ, Deng HJ, et al. Antibody responses to SARS-CoV-2 in patients with COVID-19 [published online ahead of print, 2020 Apr 29]. Nat Med. 2020;10.1038/s41591-020-0897-1. doi:10.1038/s41591-020-0897-1
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