The answer is yes: they are working well and luckily the foibles are generally mild. Globally there are eleven different vaccines currently in use, but so far only 2% of the world’s population has been vaccinated. We need to do better, including vaccines that don’t have elaborate requirements for transport or refrigeration. Another 251 vaccines are at some stage of development including 60 that are entering human trials. Let me tell you about some of the very promising ones.
Vaxxinity Pharmaceuticals has created a vaccine using proteins from the Corona Virus spike protein that are the ones that allow the virus to attach to and invade human cells. Another company, Novavax, has also developed a spike protein vaccine but theirs is directed to the entire protein, not just the “latch-on” portion. Both vaccines are very promising and early trials indicate they will work against corona variants.
Vaxart Pharmaceuticals had developed on oral vaccine that uses the common cold virus (adenovirus) to carry pieces of the corona virus through a hybrid technology. Johnson and Johnson and AstraZeneca use the same technology in their injected vaccines which work very well.
There are two big advantages for an oral vaccine. One is that it is easily administered, not requiring refrigeration. The other is a dual protection mechanism. Oral vaccines, uniquely, provide both “blood stream” protection (as do all injected vaccines) but also mucus membrane protection. Oral vaccines lead to antibodies being present on the mucus membranes of the nose,
mouth and lungs as a first line of defense against the virus. Historically there was a similar segue for polio vaccines from Dr. Salk’s injected vaccine to Dr. Sabin’s oral “sugar cube” vaccine.
Another advantage of Vaxart is that it elicits an immune response to both the spike protein and the N protein on the Corona virus (Johnson and Johnson and AstraZeneca only elicit spike protein antibodies). This may be important for mutant variants because they alter the spike protein much more rapidly than the N protein.
Valneva Pharmaceuticals is using a killed whole virus vaccine with two adjuvants (substances that enhance immune response). Several killed virus vaccines are already in use (made by Sinopharm, Sinovac and Bharat Biotech) but they do not include the immune booster adjuvants.
Inovio Pharmaceuticals uses a DNA vaccine that is injected just under the skin with multiple tiny needles and then zapped into cells via a handheld wand that releases a split-second pulse of electricity. From there the cells produce the spike protein which cues an immune response. No other vaccine uses this delivery system. So far, patients report much less discomfort from the vaccine and also fewer side effects. Since the vaccine consists of only DNA and saline it can be stored at room temperature.