Read: We dont even have a COVID-19 vaccine, and yet the conspiracies are here

The good news, because it is worth saying, is that experts think there will be a COVID-19 vaccine. The virus that causes COVID-19 does not seem to be an outlier like HIV. Scientists have gone from discovery of the virus to more than 165 candidate vaccines in record time, with 27 vaccines already in human trials. Human trials consist of at least three phases: Phase 1 for safety, Phase 2 for efficacy and dosing, and Phase 3 for efficacy in a huge group of tens of thousands of people. At least six COVID-19 vaccines are in or about to enter Phase 3 trials, which will take several more months.

We are almost five months into the pandemic and probably another five from a safe and effective vaccineassuming the clinical trials work out perfectly. Even when a vaccine is introduced, says Jesse Goodman, the former chief scientist at the Food and Drug Administration, I think we will have several months of significant infection or at least risk of infection to look forward to.

All of this means that we may have to endure more months under the threat of the coronavirus than we have already survived. Without the measures that have beat back the virus in much of Europe and Asia, there will continue to be more outbreaks, more school closings, more loneliness, more deaths ahead. A vaccine, when it is available, will mark only the beginning of a long, slow ramp down. And how long that ramp down takes will depend on the efficacy of a vaccine, the success in delivering hundreds of millions of doses, and the willingness of people to get it at all. It is awful to contemplate the suffering still ahead. It is easier to think about the promise of a vaccine.

Theres a lot of hope riding on these vaccines, says Kanta Subbarao, the director of the World Health Organizations flu collaborating center in Melbourne, who has also worked on other coronavirus vaccines. Nobody wants to hear its not just right around the corner.

Vaccines are, in essence, a way to activate the immune system without disease. They can be made with weakened viruses, inactivated viruses, the proteins from a virus, a viral protein grafted onto an innocuous virus, or even just the mRNA that encodes a viral protein. Getting exposed to a vaccine is a bit like having survived the disease once, without the drawbacks. A lot remains unknown about the long-term immune response to COVID-19, but, as my colleague Derek Thompson has explained, there are good reasons to believe getting COVID-19 will protect against future infections in some way.

Vaccine-induced immunity, though, tends to be weaker than immunity that arises after an infection. Vaccines are typically given as a shot straight into a muscle. Once your body recognizes the foreign invader, it mounts an immune response by, for example, producing long-lasting antibodies that circulate in the blood.

More:

A Vaccine Reality Check - The Atlantic