Syringes would be easier to adulterate, are made of plastic (could have substances that modify or mess with the vaccine compounds, glass is inert and clean) and

Syringes would be easier to adulterate, are made of plastic (could have substances that modify or mess with the vaccine compounds, glass is inert and clean) and would add several extra problems in the manufacturing part like leakage, disassembling when filled or breaking. Following the same reasoning an even better way to do it would be a big bottle connected with a machine that would deliver the correct dose. Such machine should fulfill at least the next points 1) Assure the vaccine integrity and identify. Grant that the product has not been modified at any point (closed metallic bottle that can't be pierced or manipulated with an official seal difficult to duplicate or fake. 2) Keep the product refrigerated and watch its temperature all the time. 3) Travel. A metallic bottle would stand transport much better than glass and would need less packaging materials. Autonomous system can be just put in a pickup and moved to places without accurate refrigeration. Not need to build expensive rooms or hospitals and reaching isolated areas 4) Assure the same dose to everybody and change automatically the needle without the need of any human hand near the needle's boxes. Avoiding injuries and diseases 5) Discard safely the used needle and trow it into a secure recycling compartment. 6) Allow people to enter their own personal data and ID card in a keyboard or card slot before being vaccinated. then, keep this data safe stored into a database far from curious eyes 7) Share the number of vaccines used in real time or almost with the other teams. Thus the government could know what machines must be refilled and how many old needles boxes should be replaced in real time and plan according. If a place is not getting enough stream of people, the machine could be recalled to the next near place that is too busy 8) Avoid the human factor. Machines are tireless and fast. Don't need to make breaks or sleep as humans, don't care about skin color and can be bribed by local corrupts or the hate department. Automatic vaccining machines could made a bigger difference than vaccines prepackaged in syringes, for sure, I wonder why nobody has created one still.