The hope for a successful Covid-19 vaccine took steps forward and back lately. Reports of positive outcomes in the Pfizer, AstraZeneca and Moderna trials have optimism high that a successful vaccine could be on tap for later this year or early 2021, though recent biological study of the virus and what we know of other coronaviruses bring to light questions about the long-term viability of any vaccine that modern medicine can throw at the pandemic.
In early phases of ongoing Covid-19 vaccine trials, results have been encouraging, as the drugs have been creating immune responses in test subjects. All three of the results that have been released recently have shown successful antibody activity, with both neutralizing antibody and T-cell responses. These early-phase success stories are promising, but will need to be backed up by positive Phase 3 testing on the level of thousands of test subjects before moving toward the market.
The downside of recent news lies in the behavior and scarcity of the specific antibodies that can fight off the coronavirus. The National Institutes of Health, which is working alongside Moderna’s vaccine trials, released an article in June stating that less than 1% of those tested that had recovered from Covid-19 had high levels of the antibodies most successful in defending the body from the virus. Seeing these antibodies in action will be key in the production of vaccines, but the limited nature is a concern.
Further complicating matters, an article from William A. Haseltine of Forbes Magazine reported that “several recent studies have found that antibodies to SARS-CoV-2 decline in strength and number in the weeks and months following infection.” Knowledge that the antibodies that we will be counting on to combat this pandemic are not only rare, but also work in a limited timeframe, raises questions about just how reliable any vaccine can be.
The other concerning piece of information comes from our longstanding history with coronaviruses. According to Hasetline, the Covid-19 virus is similar to the four coronaviruses that are known to cause around a third all common colds. From our experience and lack of success in avoiding colds, we know that these same four viruses hit each and every year without reprieve. Unlike the flu, the coronaviruses have not baffled us with different strains each year, but simply return again and again in familiar forms and with very little by way of immunity to stand in their way.
A new virus requires new research, and science, by its nature, is not a fast-moving ordeal. Further vaccine testing and antibody research will continue over the coming months and years, and the hope for a successful merging of the two studies may be the lynchpin in containing the pandemic that the world has struggled and failed to control over the past eight months.