The COVID-19 vaccines are being rolled out worldwide in an effort to put the pandemic under control. And while the intramuscular jabs appear to be doing a good job in providing protection against the novel coronavirus, experts and scientists are still looking for ways to improve the process of vaccination by examining other means of administering the immune-boosting biological preparations.

The Intranasal Route As An Alternative

Saying that a drug is administered via the intranasal route basically means that the drug is dispensed through the nasal structures. This type of drug delivery is considered noninvasive since it does not require the introduction of an instrument into any part of the body. On the other hand, the intramuscular route is considered invasive since it involves the penetration of a needle into the skin. From this comparison alone, it would make sense for scientists to come up with a vaccine that can be delivered in a noninvasive manner.

However, the driving force behind the efforts to make nasal COVID-19 vaccines goes beyond the invasive vs. noninvasive argument. The medical experts and scientists who are working on this new breed of vaccines are seemingly after one more important thing — sterilizing immunity, according to Stat. This type of immunity provides a kind of protection that could block all sorts of infections that enter and start out at a specific part of the body. In the case of the novel coronavirus, it’s the nasal passage.

SARS-CoV-2, the causative agent of COVID-19, attacks the respiratory tract upon entry through the nose. Scientists feel that it would just be right for them to come up with intranasal vaccines that could better protect the mucus membranes of the nose and throat than the intramuscular jabs. Even though achieving sterilizing immunity through nasal vaccines is a bit uncertain, there is no reason to believe that having vaccines administered through the nose wouldn’t do a better job in blocking COVID infection than the existing shots.

Advantages Of Intranasal Vaccines

An intranasal vaccine can readily provide protection to the mucus membranes of the nose and throat because it is delivered through the nose. The intramuscular shots are also capable of providing the same type of protection once they have induced high enough levels of circulating antibodies that could reach the nasal passage. Unfortunately, this type of protection wanes over time once the antibody levels start to drop months after vaccination, Icahn School of Medicine at Mount Sinai Hospital vaccinology expert Florian Krammer told Stat.

Intranasal vaccines wouldn’t need syringes, so it would be easier for them to be administered to children and people who have a phobia of needles. A study published online by Cambridge University Press in June indicated that blood-injection-injury fears could be contributing to the vaccine hesitancy by a number of people in the adult population. The same study found that injection fears were quite high in the youth population as well.

Another noteworthy advantage of having nasal vaccines over intramuscular shots has to do with the medical waste they produce. Because intranasal vaccines wouldn’t need syringes for their administration, it goes without saying that there would be less medical waste when they are used in vaccination programs. This would also reduce the preparation expenses since the containers of the nasal vaccines also serve as their dispensers. Meanwhile, existing vaccines incur more expenses and yield more waste since each drug delivery involves the use of a vial and a syringe.

Existing COVID vaccines are also at a disadvantage compared to intranasal ones when storage and shelf life are considered. Some mRNA vaccines require very cold refrigeration for them to stay viable, and this could be a big problem in places with inadequate infrastructure, medical equipment or even electricity supply. Nasal spray vaccines that are currently in the works and being tested are said to not require any refrigeration, making them more favorable for countries with logistical problems, according to Gavi.

Ongoing Trials For Intranasal Vaccines

Many countries are currently in the process of developing COVID vaccines in nasal spray form. Thailand recently announced that it will begin testing coronavirus nasal sprays on humans soon, following the success of its trials on mice. The country’s deputy government spokeswoman Ratchada Thanadirek told Reuters that should the human trials go well, they could move forward with producing the nasal vaccines for wider use in mid-2022.

Aside from Thailand, Canada is also looking into developing its own nasal spray vaccines for COVID-19. However, the North American country is also keen on creating a range of defenses against the novel coronavirus. For instance, labs led by Dr. Marc-André Langlois, a researcher at the University of Ottawa, are experimenting on therapeutic and diagnostic antibodies as a means to fight off COVID-19, alongside a nasal spray vaccine.

Other countries that are also working on non-injectable vaccines include the U.S., the U.K., India and China, as per Should testing and clinical trials come to fruition, the world could expect a greater rollout of the noninvasive vaccines that many experts view as a good solution to the low vaccination rates in certain places.