Prior to the novel coronavirus, seasonal forms of influenza would spread on an near annual basis. It is estimated that anywhere from 290,000 to 650,000 people pass away from influenza each year. While influenza vaccines exist, the issue remains that influenza viruses mutate every year, resulting in a situation where the manufactured vaccines may not be as effective as desired. This same issue applies to the novel coronavirus, which has repeatedly continued to mutate.
Miyu Moriyama of Yale University aims to develop a "universal influenza vaccine" that will be effective against heterologous strains of influenza viruses. Through her research, Moriyama has demonstrated that administering vaccines through respiratory mucosal surfaces such as those in the nose and lungs can provide effective mucosal immunity against different mutant strains. This had previously not been able to be achieved with conventional subcutaneous injections.
Building on such achievements in research in mucosal immunology, Moriyama is currently leading joint research efforts with institutions such as the University of Pennsylvania into Prime and HA (international patent pending), an intranasal influenza vaccine. While traditional injectable vaccines deliver memory lymphocytes throughout the body via the bloodstream, Prime and HA differs in that it confines memory lymphocytes to the respiratory mucosal surfaces. Since intranasal vaccines do not require the use of injection needles, an increase in vaccination rates can also be expected with their practical introduction.
Furthermore, some common vaccines contain substances called "adjuvants," which enhance a vaccine's effectiveness by eliciting a robust immune response. However, in rare cases, adjuvants may cause severe adverse reactions, especially with intranasal administration. The Prime and HA vaccine currently being developed by Moriyama does not contain adjuvants, making it both an effective and safe option.
If a universal influenza vaccine such as Prime and HA were to be introduced for practical use, it could significantly reduce the impact of seasonal influenza. Furthermore, if similar technology could be applied to other infectious respiratory diseases such as the novel coronavirus, such technology could aid in preparation for future pandemics.