Going viral: five of the most important things we’ve learned about Covid-19 so far Even though it’s been only six months since we first heard about a novel coronavirus circulating in China, so much has happened that it’s all a bit of a blur. What we do know is that we have a long way to go and there are many challenges that lie ahead of us. Although many countries have managed to gain control over virus transmission for now, these past few weeks in Victoria have highlighted how quickly things can turn and how little it takes for a resurgence in case numbers to occur. There is still much that we don’t understand completely, including key matters like how it affects the body and the way the immune system responds to infection. But every day we spend with this virus we are gaining a greater understanding of it, which means we are better placed to bring this pandemic under control and save lives. Here are five of the most important things we’ve learnt so far. 1. A global pandemic is not just science fiction Related: A foreseeable catastrophe: how Covid-19 swept through Victoria’s nursing homes Up until now many of us have thought that a viral pandemic of this scale was just a recurring Hollywood science fiction movie plot. Despite the warnings of epidemiologists for years, we have only now come to truly appreciate how much of a threat this type of event is. Although we’ve had a taste of what pandemics look like, with Sars, H1N1 influenza and Ebola, none of these diseases compare with Covid-19 in terms of reach and impact. For the first time since the 1918 flu pandemic, the world has seen a disease both highly infectious and severe representing a global threat to health. And what we’ve seen so far has confirmed our worst fears: the virus is spreading rapidly, overwhelming health systems and resulting in hundreds of thousands of deaths. 2. The pandemic is not just a health crisis Previous pandemics have shown that these are cataclysmic world events that do not just affect the health of the population, but rather all aspects of society. This is what we are seeing now as we now find ourselves having to navigate the cumulative effect of a global health emergency paired with a global recession. There is no doubt that substantial challenges lay ahead and the effects will most certainly outlast the virus itself. Already we’ve seen major changes in, for example, the way we interact with each other, the way we work, the way we study, and the way we access healthcare. Despite the extensive challenges, the pandemic has also revealed how adaptive and resilient we can be individually and as communities when faced with adversity. While technology has been vital in allowing us to navigate a number of issues caused by the pandemic, it is also clear that it can’t address them all. 3. Things turn out better if we listen to experts The pandemic has confirmed the value of listening to experts. Those governments that listened to public health experts and epidemiologists have had dramatically better outcomes than those who ignored them. In particular, countries that took on board advice to act quickly and decisively have been able to get on top of disease transmission and save thousands of lives. We’ve seen that even delaying action by days can be the difference between restricting the disease’s spread and seeing it spread uncontrollably. There are no better examples of the effect of early and decisive action than looking at what Australia and New Zealand have been able to achieve in bringing disease spread under control. In contrast, countries like the UK and the US have paid a high price for not listening to the experts, being in denial in the early stages of the pandemic, and delaying action. 4. Pandemics do not affect all people equally Related: Australia’s Covid-19 lockdown rules and coronavirus restrictions explained Pandemics expose inequalities – both between countries and within countries. Poorer countries will suffer the most due to Covid-19. These countries, with their weak health systems, lack of resources and large vulnerable populations, will find it more difficult to cope with a shock of this magnitude. In addition to the health and economic costs faced by all countries, many of these poorer ones are also at risk of food security, employment and political crises. The same disproportionate burden of this pandemic on the most disadvantaged is being seen within wealthy countries. There is no better example of this than the plight of black Americans in the catastrophe that is unfolding in many parts of the US. With greater levels of poverty, poorer access to health services, andhigher rates of co-morbidities, black Americans are being disproportionally affected by Covid-19, both in terms of health and economic impacts. 5. Making a vaccine is not an easy thing to do The pandemic has taught us that making a vaccine to Covid-19 – despite the vast technological and medical advances made in recent times – is going to be extremely difficult. It doesn’t matter how much money or effort we throw at this, there is a possibility that we may not succeed. And if we do, it may take longer than we all are hoping for. You only need to look at the story of HIV/Aids to get a reality check on how difficult it is to produce a vaccine. We have been working on an HIV/Aids vaccine for more than 30 years and have poured billions of dollars into this and we still haven’t succeeded. Still, with governments, scientists and pharmaceutical companies working together in a way we have not seen before, and on a scale we have not previously seen, there is cause for hope. We have more than 100 vaccine candidates now being tested and many of these have reached the human trial stage already. We only need one of these to be successful for it to be a game-changer. • Hassan Vally is an epidemiologist and associate professor in public health at La Trobe University