Abstract
Time has seemed to move faster than usual during the coronavirus disease 2019 (COVID-19) pandemic. Over the past 2 years, I have often wondered what we will think when we reflect on the pandemic years from now. Will we realize the mistakes that were made? Will we marvel in the advances that were achieved? Will we plan to do things differently next time? One topic that will resonate for many years to come will be that of vaccines. Despite great progress, there has been polarizing opinion on vaccines throughout the current pandemic. It would be interesting to compare vaccine hesitancy before versus after the pandemic given the passionate discourse we have seen on this topic.
I think most scientists will agree that this was a good time for vaccine research. These days it seems like everyone, even young children, knows more about vaccines, antibodies, and booster shots than we did a few years ago. Perhaps a contentious topic, but it is hard to argue with the notion that the rapid development of the COVID-19 vaccines saved many lives and perhaps helped us move beyond the pandemic faster than would have been possible had vaccines not been available in record time. Although we cannot forget that such vaccines are still not widely available in many places.
The currently available vaccines are doing exactly what they have claimed to do—they are keeping people alive by reducing disease severity in most infected individuals. We are still very much in a pandemic and, therefore, we are still fighting the virus with the weapons we currently have available, but I wonder will we have better weapons someday? Virus-specific antiviral agents are trickling in slowly, but I wonder whether we will also see different COVID-19 vaccines at some point in the future, those that demonstrate high effectiveness at preventing actual infection. Will we be content to prevent most serious illness? Or will there be vaccines that actually close the door on the virus for many years?
Time will answer these questions. We have seen some silver linings and changes associated with the pandemic that have brought about positive change and new developments that will benefit us in the future. One such silver lining is the heightened interest and rapid evolution we have seen in vaccines and vaccine research. Three years ago, no one would have believed that millions of people would be getting injected with nanoparticles containing mRNA against a virus we did not yet know existed. The possibility of another pandemic had been looming for decades, and so was not really a surprise for anyone following emerging viruses, but how many among us expected this level of impact on vaccine development?
In this issue, we have selected a number of articles with direct relevance to vaccine research to profile some of the new ideas emerging from the vaccine world. Maragkakis et al. investigated the impact on Fas-mediated cell death with intradermal versus intramuscular vaccination using a commercial porcine respiratory and reproductive syndrome vaccine. Khalil et al. evaluated alternative tests for potency of rabies vaccines. Mohammed et al. explore the possibility of using a biodegradable synthetic polymeric nanoparticle-based vaccine against hepatitis B virus. And finally, in an effort to increase immunogenicity of potential HIV-1 vaccines, Rezaei et al. employed a strategy whereby an HIV-1 vaccine was adjuvanted with bacterial flagellin.
Much effort remains directed at diagnosis of COVID-19 and understanding the immune response against the virus and the vaccines developed to fight it. Deshpande et al. examine the clinical performance of serology-based commercial severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) diagnostic assays. Two articles focus on antibody responses in individuals receiving an inactive SARS-CoV-2 vaccine (Zhou et al.) and individuals infected with the virus (Aziz). Another study, by Mahallawi et al., analyzed antibody responses in individuals who received a single dose of COVID-19 vaccine subsequent to infection with SARS-CoV-2. Finally, Koryukov presents a case study in which they ask whether the Sputnik V vaccine induces immunity against seasonal coronaviruses.
Necessity drives innovation, and there will always be new viruses. So we will always need new vaccines, as well as new and better ways to make vaccines.