The answer to stopping the coronavirus may be up the nose

The COVID-19 vaccines authorized for use today were developed at an unprecedented speed and exceeded expectations of how well they worked. Billions of people protected by him have survived severe symptoms, hospitalizations and death. These vaccines are a scientific breakthrough beyond measure.

And yet they can be even better.

The enemy has evolved, and the world needs the next generation of vaccines to respond. This includes vaccines that completely prevent coronavirus infection.

When the initial mRNA vaccines were first authorized in December 2020, the world was battling a different kind of pandemic. The dominant strain circulating had relatively little potential for spread between people. At the time, mRNA vaccines not only provided strong protection against serious illness and death, but they were also highly protective against infection and the spread of viruses.

But SARS-CoV-2 continued to mutate, and in doing so it has given rise to forms that are more infectious and able to shed around protective antibodies, leading to widespread infection, immunity from vaccines and prior infections. Despite the rising level of Thankfully, mRNA vaccines are still very effective in preventing hospitalizations and deaths, including the highly infectious Omikron variant, after the booster shot.

So, one might ask, why should we worry about infections if we can eliminate serious disease and fatality risk through a combination of existing vaccines and treatments?

Even mild infections can develop into protracted covids with people suffering from long-lasting, debilitating symptoms. The data also suggests that groups such as older adults who have been vaccinated but have not received their boosters may be at higher risk for the worst outcomes of COVID-19.

Regular infections can cause severe disruption to people’s lives, affecting their ability to work and keep their children in school. There is also no guarantee that people infected with Omicron will be safe from future infections.

One change that could make vaccines more effective is if they can stop the virus from getting in its way as soon as it enters the body. This can completely reduce the infection, as well as reduce the spread of the virus.

The currently available COVID-19 vaccines are injected into people’s arm muscles and are highly capable of combating the virus when people become infected. But they are not as successful in preventing people from getting infected in the beginning. To do this, you ideally want to prevent a virus from spreading in a place where people are infected: the nasal cavity.

That’s why groups of scientists, including me, are working on nasal covid vaccines. Ideally, a nasal vaccine can penetrate the mucus layer inside the nose and help the body make antibodies that take hold of the virus, not even giving it a chance to attach to people’s cells. Is. This type of immunity is known as sterilizing immunity.

By catching the virus at the site of infection, the antibodies induced by the nasal vaccine can help the body fight off the virus before it causes symptoms. Not only may nasal vaccines be better positioned to prevent infection, but they may also develop the same immune system defenses as other vaccines, and may be even stronger because this immune memory protects against virus entry. is on the portal. These vaccines can establish highly protective memory B cells, which make faster and better antibodies for future infections, and memory T cells, which help kill infected cells and support the production of antibodies.

These types of vaccines are traditionally considered more difficult to make. The mucus layer is a formidable barrier. The body does not produce a strong immune response even by spraying any conventional vaccines on the nose. The approved nasal vaccine for the flu, called FluMist, uses a weakened virus to get into cells in the nose and induce an immune system response. But this method is not safe for use in immunocompromised people.

The good news is that scientists like me believe we have found a way around this problem for SARS-CoV-2. We have shown in animal studies that we can nasally spray the virus’s so-called spike protein into a previously vaccinated host, reducing infections in the nose and lungs as well as providing protection against disease and death. . Combining this approach with efforts to develop a single vaccine for a wide range of coronaviruses could potentially protect people from future variants as well.

A big question is how long immunity from the nasal vaccine will last. So far in animal studies, antibodies and memory immune cells in the nose persist for months. Should this immunity wanes over time, like other vaccines, using nasal sprays as boosters – potentially over the counter – every four to six months may make the most sense for this pandemic.

This presents the same challenges as other boosters, where the uptake can be very high, especially for high-risk groups. It’s important to encourage people to get their boosters. But the barrier to a nasal spray booster may be less for many people than a needle shot.

The world desperately needs a vaccine strategy

Guard outside the gate to prevent viral invaders from infecting us. There are several other nasal vaccines in various stages of clinical trials. And whatever success we have achieved in developing a nasal vaccine for COVID-19 will not be limited to this one virus. Nasal spray vaccine strategies can also be applied to other respiratory pathogens.

While there are some remaining hurdles, the potential immunological and public health benefits of nasal spray vaccines deserve attention now and for years to come.

Originally published at Pen 18