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David Hunter, professor of epidemiology and medicine, University of Oxford, UK

There is a lot of discussion about a second wave, and when is a wave a wave, or will it be a ripple. Or some people suggest that a better analogy is tides. I sincerely hope there won’t be another pandemic like in March-April, that it would be much more attenuated. I suspect it will be, because we’ve got a lot of things in place: a better-educated population, social distancing, handwashing and mask-wearing.

That should mean that the epidemic curve is attenuated. If we can, as the virus persists, do a better job of protecting the very old, there should be many fewer deaths, even if there are a lot of infections. So we’re in a much better place than we were six months ago, and even if there is a second wave or the tide comes in again, hopefully there’ll be a lower fatality rate.

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Devi Sridhar, professor of global public health, University of Edinburgh, UK

If you have mass-testing capabilities, you could clear the virus. And then you add into the mix a vaccine, perhaps by early 2021.

If we move towards the saliva-based tests that are rapid and cheap, that’ll make testing easier. There are ways to get around testing everybody on a weekly basis if you use your testing in a strategic way, targeting where your highest risk is. But at the start, we can’t get around that we’re going to need millions of tests, and the logistics are complicated.

Another scenario is that we may see a certain strain of this virus that is more infectious but less severe start to become the predominant strain, but I think that is years away. The third bet is T-cell immunity. We have antibody tests, but some immunologists think that antibodies underestimate the number of people who have protection. Could we already have more people exposed to this than we think?

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Zoë Hyde, epidemiologist, University of Western Australia

I am hopeful that high-income countries such as Australia will be able to start a vaccination programme early next year, assuming phase III trials are successful. A vaccine won’t immediately make things return to normal. The first vaccines might not be sterilising – however, I think they will be sufficient to get our economies functioning again. We can then explore options such as boosting with a different type of vaccine.

The picture won’t be so rosy in many low-income countries, as they will struggle with the logistics of vaccinating their populations.

I am concerned about India, which is on track to become the epicentre of the pandemic. In addition to the human cost, I expect there to be global implications because of its key role in the manufacture of pharmaceuticals. The knock-on effects would be felt most strongly in the developing world, where interruption to the supply of medicines could lead to many indirect deaths.

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Benjamin Cowling, professor of epidemiology and biostatistics, University of Hong Kong, China

We are hoping to get a vaccine probably next April to June. We’ll vaccinate the most vulnerable people first. So what we may see is that we still have some social distancing, but maybe not as strict as right now – just trying to slow down the spread so that we can vaccinate everybody. And then things can go relatively more back to normal.

But even after a whole population has been vaccinated, if the effectiveness isn’t as good as we hoped for, or if a strain of the virus emerges that can escape the vaccine protection, then we’re going to see winter epidemics of covid-19, like we do for flu. Even in a vaccinated population with partial protection, a winter outbreak of covid-19 could still cause more impact than a winter epidemic of flu because, on an individual basis, [covid-19] is 10 to 20 times more serious.

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Raina MacIntyre, head of biosecurity research, Kirby Institute, University of New South Wales, Australia

In the absence of an effective vaccine, we’re going to have waxing and waning periods of the epidemic, and these will vary by country. There will be more disease around and health systems will be stressed, and then interventions will be brought [back] in. It will cycle.

It may not be that far away before we have vaccines, sometime next year hopefully. But you’re not going to be able to make 7 billion doses overnight. Rich and powerful countries will probably buy up a lot of the supply and other countries will have to stand in line.

If you can’t achieve mass vaccination in those countries, you could just chase the outbreaks and do ring vaccination. That’s what happened with smallpox, and with Ebola as well. That’s when, if you have an outbreak, you vaccinate all close contacts.

But we’re going to have hotspots of covid-19 in the world for a long time. Smallpox took more than 20 years to eradicate – that’s the time frame we’re talking about living with covid-19.