There are basically two ways…
1. The virus could “burn out” (like SARS and MERS) due to effective public health mitigation measures and immunity. BUT, given the ease of transmission (most contagious two days BEFORE symptoms) and given our lack of a national (and international) coordinated response, this is very unlikely now.
2. We could reach “unnatural” herd immunity (ie vaccines). Eradication is 100% dependent on vaccine effectiveness and uptake. We don’t know either yet. If a vaccine prevents clinical disease, strongly reduces transmission and produces long-lasting immunity, eradication is possible. But realistically this is unlikely, especially since it’s clear our next public health hurdle is getting people to trust the vaccine once a safe option is available. “Natural” herd immunity is out of the question.
Option numero two…Pandemic turns into an endemic.
In other words, COVID19 goes on to live among us, like it’s cousins (common cold) or other infectious diseases (HIV or malaria). A pandemic turning into an endemic it’s based on a very loose definition: how risks are perceived by the population. For example, HIV is technically still a pandemic (it’s in every country across the globe). However we’ve found therapies, prevention methods, and the level of awareness has (almost) reached saturation. The “newness” has withered and we have gone on to live with HIV. HIV is now considered an endemic.
If COVID-19 does become an endemic virus, there’s no way of knowing where it will be most prevalent (on the equator like malaria?), when it will be most prevalent (will it be seasonal like the flu?) or what the baseline level of disease will be (eventually this will stabilize at a constant level, R(t)=1).
How we deal with COVID-19 once it becomes endemic will depend on four things. Our interventions (vaccines and treatments) are key aspects. If they can protect people from the most severe outcomes, the infection will become manageable. COVID-19 will then be something we learn to live with and something many people will experience during their lives.
Like everything in this pandemic… TBD.
Here is a published scientific perspective that complements my perspective if you’re interested (and skeptical): https://science.sciencemag.org/…/10/13/science.abe5960