Vaccines take time to work. You get a vaccination and over the next couple of weeks, the body's immune system starts to develop a response to whatever you got vaccinated for. If you need a booster shot, then that usually happens a couple of weeks after the first shot. During this time, you are still susceptible to catching the virus. So even though you might be vaccinated in September, you will still be able to catch the virus for about a month after that, and if you do catch the virus, you can transmit it to people who haven't been vaccinated.
There is also an issue of the vaccine not producing an immune response in everyone. So you and your family get vaccinated. A month later you are presumed to be protected. However, the vaccine doesn't work on one of your family members for whatever reason. That person still has no immunity to the virus and you or other people can spread it to them (if you have it). Even if you are vaccinated for it, if someone coughs on your clothing and someone else handles those clothes, they could catch the virus from your clothing.
It also takes time to vaccinate everyone. You might get done in September, but it could be 12 months or more before the entire population is done. Again, if people aren't careful during this time, the virus can easily be spread to people that haven't been vaccinated. If babies are born during this time, they could also catch it.
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Whilst everyone is hopeful the vaccines will work, they might not work. And it will probably take a couple of years to vaccinate the world's population regardless of if it works, so don't expect this to end soon. My guess is we have another 6-12 months (possibly longer), before we see any major changes.
To make matters worse, this may not be the last viral pandemic outbreak. There have been 6 new viruses (potential pandemics) that have appeared in the last 20 years. Overcrowding, overpopulation, encroachment into wild areas, malnutrition, poor sanitation and numerous other factors all contribute to new viruses appearing. We might all be vaccinated against covid19 and get back on with our lives only to have another virus pop up in a couple of years time.
The fact is the planet is overpopulated with humans and whenever you have large populations of any creature, there is a risk of disease outbreaks. This happens on farms, in fish tanks, aviaries, and in human towns/ cities. Combine that with global warming, fires destroying the bush, people hunting and eating wild animals, and the pH in the oceans about to drop, I don't have a lot of hope left for the human race or any other species on the planet. The Earth could soon become another Mars and the human race disappears forever.
