Covid-19 vaccines are incredibly good at preventing severe symptoms and hospitalization, but they’re probably less effective at stopping transmission. To do that, we might need a different kind of vaccine altogether.
Because SARS-CoV-2 is mainly transmitted through droplets and airborne aerosols, some scientists reason that a vaccine should provide first-line protection where the virus typically enters the body — the nose. A Covid-19 vaccine that’s sprayed into the nose may not only prevent people from getting sick in the first place but also stop them from spreading the virus to others.
“When you get Covid-19, you don’t get injected with the virus. You get it in your respiratory tract,” Matt Memoli, MD, a virologist at the National Institute of Allergy and Infectious Diseases, tells the Coronavirus Blog. “So, you don’t need antibodies in the blood to prevent infection there. You need antibodies at the site of infection at the mucus membranes, at the airways.”
All vaccines are designed to spur the production of protective immune proteins called antibodies. Most vaccines are injected into the muscle, which stimulates serum antibodies that circulate in the blood. Serum antibodies are generally very effective at protecting against serious disease.
A nasal spray vaccine, on the other hand, generates antibodies that are secreted by the tissue that lines the inside of the nose. Antibodies here can block the incoming pathogen at the site of infection. This type of immunity is known as mucosal immunity. FluMist, a nasal spray vaccine for flu, works this way.
Without protective antibodies in the nose, those who get an injected Covid-19 can harbor viral particles there even if they don’t have disease symptoms themselves. That means it’s still possible for people to pass on the virus even if they’re vaccinated.
The authorized Covid-19 vaccines by Moderna, Pfizer, and Johnson & Johnson aren’t designed to generate mucosal immunity, but there’s some indication that they do…
Image Credit: AP
Post by Amanda Scott, NA CEO. Follow her on twitter @tantriclens
Thanks to Heinz V. Hoenen. Follow him on twitter: @HeinzVHoenen

News
Emission of Fe- and Ti-Containing Nanoparticles from Coal-Fired Power Plants
In an article published in the journal Science of the Total Environment, researchers have highlighted the significance and potential risks associated with the release of nanoparticles from coal-fired power plants. Applying the single-particle inductively coupled plasma mass [...]
Covalent Organic Framework Nanofluidic Hybrid Membrane for Osmotic Energy Generation
A paper recently published in the journal ACS Applied Energy Materials demonstrated the feasibility of using a covalent organic framework (COF)-based nanofluidic hybrid membranes (NHMs) to attain enhanced interfacial ion transport for the generation of osmotic [...]
Degradable Nanocomposite Removes Antibiotics from Contaminated Water
The excess fluoroquinolones (FQs) discharged into the aquatic environment due to human activities must be removed cost-effectively. In an article published in the Journal of Cleaner Production, the authors fabricated an environment-friendly dealkaline lignin-grafted Fe3O4 nanoparticles [...]
Light-controlled reactions at the nanoscale
Controlling strong electromagnetic fields on nanoparticles is the key to triggering targeted molecular reactions on their surfaces. Such control over strong fields is achieved via laser light. Although laser-induced formation and breaking of molecular [...]
Bright Future for Nanophotonic Chips with Topological Rainbow Device
A paper recently published in the journal Nature Communications demonstrated an effective method to realize on-chip nanophotonic topological rainbow devices using the concept of synthetic dimensions. Importance of Synthetic Dimensions for the Construction of Topological Nanophotonics [...]
Green Approach to Silver Nanoparticle Fabrication with Citrus Fruits
In a study available in the journal Materials Today: Proceedings, silver nanoparticles (Ag NPs) were fabricated using a green method using Citrus X sinensis. Methylthioninium Chloride (MB) Dyes Threatening the Environment Dye and sewage drainage into [...]
Coronavirus ‘ghosts’ found lingering in the gut
Scientists are studying whether long COVID could be linked to viral fragments found in the body months after initial infection. In the chaos of the first months of the coronavirus pandemic, oncologist and geneticist [...]
Experts perplexed over number of people getting long COVID
Public health experts are divided over how many people are getting long COVID-19, a potentially debilitating condition that comes after a patient has recovered from the coronavirus. Ill effects from the condition can include [...]
Four strange COVID symptoms you might not have heard about
Well over two years into the pandemic, hundreds of thousands of COVID cases continue to be recorded around the world every day. With the rise of new variants, the symptoms of COVID have also evolved. Initially, [...]
A new method for exploring the nano-world
Nanoparticles are everywhere. They are in our body as protein aggregates, lipid vesicles, or viruses. They are in our drinking water in the form of impurities. They are in the air we breath as [...]
Breast Cancer Drug Resistance Tackled By Polymer Nanoparticles
Drug resistance is a common phenomenon, with drugs becoming less and less effective as their usage increases. To address this issue, a novel technique employing conjugated polymer-based nanoparticles is presented in the study published [...]
New imaging method makes microrobots visible in the body
Microrobots have the potential to revolutionize medicine. Researchers at the Max Planck ETH Centre for Learning Systems have now developed an imaging technique that for the first time recognises cell-sized microrobots individually and at [...]
Multifunctional Nanocrystals Enhance Cancer Cell Killing Therapies
Scientists have recently developed multifunctional hexagonal NaxWO3 nanocrystals that can serve as microwave sensitizers to kill cancer cells as well as improve the overall chemodynamic therapy (CDT). This study is available as a pre-proof in Chemical Engineering Journal. [...]
Biotech, nanomedicine, and AI combine for health breakthrough predicted by Apple genius Steve Jobs
Apple’s visionary founder, the late Steve Jobs once said, “the biggest innovations of the 21st century will be at the intersection of biology and technology”. And that prediction is coming true in the drug [...]
Making chemical separation more eco-friendly with nanotechnology
Chemical separation processes are essential in the manufacturing of many products from gasoline to whiskey. Such processes are energetically costly, accounting for approximately 10–15 percent of global energy consumption. In particular, the use of [...]
Dual Function SARS-CoV-2 Sensor for Point of Contact Testing
Scientists have recently developed electrochemical immunosensors based on graphene oxide−gold (GO−Au) nanocomposites. These immunosensors are highly sensitive with dual function, i.e., they can detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigen and antibody. [...]