In the shadow of the first COVID-19 pandemic and as we are slowly seeing some glims of recovery we started to get new warnings of feared threats of a second corona wave. It is difficult to forecast how such a wave would like as there are so many unknowns and variables in terms of how, when and where we will be reopening our economy, also where, when and how the second wave will take place? Here we see complex scenarios involving multi-layered ‘physical-chemical-biological’ dynamic interactions involving a wide-range of parameters and factors that we rarely experienced on the global scale in our modern urbanized lifestyle. The geological era of the anthropocene that is forming our todays reality has never been as complex and dynamic as we have it today. It is even an impossible wicked problem for our supercomputers to solve and it is only a matter of a vanishing amount luck that can save us. Yes it is a true, harsh and certain inconvenient reality. The COVID-19 will not go away by itself, why should it, and what we currently know about COVID-19 is not enough to save us as we are still blind, locked-down all together in a dark quarantine and searching about a dark object called COVID-19.

As far as we know from previous historical evolutions epidemics of infectious diseases behave in different ways. With this in mind loosen restrictions in many countries is raising concerns in the UK and Germany about the potential for a second wave and how Europe should respond. The 1918 influenza pandemic for example killed more than 50 million people in multiple waves, with the latter more severe than the first (https://www.google.se/amp/s/amp.theguardian.com/world/2020/apr/20/will-there-be-second-wave-of-coronavirus-).

It does not come with a surprise that we are getting many new alarming warns from leading expertise about a possible second wave of COVID-19 (https://www.livescience.com/covid-19-second-wave-flu-season.html; https://www.thecut.com/2020/05/second-wave-coronavirus.html). Reopening our economy without having various precautions and enough preparedness about how to deal with a possible new outbreak of a second wave is just a blind gambling. It is, therefore, legitimate and understandable that our public-health officials and private citizens alike are beginning to worry about an unknown, unsafe and insecure future. A failure this time would mean a bad fall and a bad winter with disastrous global impacts. The resurgence of COVID-19 next winter could hit many countries’ health care systems even harder than the original outbreak and this is according to the warns from Disease Control and Prevention (CDC). A second wave that may very well coincide with the start of the usual flu season in many places, i.e. a more difficult one than we just went through of a flu epidemic and a coronavirus epidemic at the same time. So there are fears in the US that the second wave could be much more severe (https://www.google.se/amp/s/www.washingtonpost.com/health/2020/04/21/coronavirus-secondwave-cdcdirector/%3foutputType=amp). In this context there are much concern and discussions what regards reopening the economy in the US (https://www.google.se/amp/s/amp.cnn.com/cnn/2020/04/29/health/us-coronavirus-wednesday/index.html). Also, if this takes place in the spring we will also have double threat from a coincidence of regional spring allergies in different parts of the world from e.g. pollen, dust/sand or other fine M2.5 particles and aerosols with coronavirus epidemic. Imagine now these can even take place in heavily polluted areas with toxic chemical and physical particulate aerosols or gases. In our globalized, over-populated and urbanized world that we live in today we need to build public health infrastructure that ensure that we have the capacity to stay in the containment mode on all levels and scales. It goes without saying that the fast wave of worldwide urbanization after the second world war and the tight interactions between humans, animal and food production systems, also the global trade and business infrastructures have definitely brought much more health risks for increasing pandemics. Much more need to be done regarding the combined effects and integrated impacts of physical-chemical-biological pollution. It is unfortunate that we examine these impacts separately as our respiratory system is without hesitation dependent on air-quality and the collective/integrated doses from these pollution sources ’physical-chemical-biological’.

Another interesting issue that strongly influencing the rate of infections and death is the age structure (https://en.m.wikipedia.org/wiki/Demographics_of_the_world) in different countries. Though the size of population in Europe and the US is 26.5% of the world population, the highest infection and death rates do exist in these parts of the world though they enjoy high living standards. One of the reasons for such high rates is that a relatively more proportion of the population in these countries is over 65 years as compared to Africa and Asia. While Africa and Asia has more younger population, e.g. under 15 years. According to 2018 world statistics (https://en.wikipedia.org/wiki/Demographics_of_the_world; https://en.wikipedia.org/wiki/List_of_countries_by_life_expectancy; https://worldpopulationreview.com/countries/median-age/) Europe has 16% under 15 years and 18% over 65 years; North America (mainly the USA) has 19% under 15 years and 15% over 65 years. The corresponding figures for Africa and Asia are as follows 41% younger than 15 years and only 3% older than 65 years for Africa; and 24% younger than 15 years and 8% older than 65 years for Asia. Africa enjoys the youngest population in the world and to a lesser extent the same for West Asia, South Asia, Southeast Asia and parts of the Americas. Part of the explanation is also related to the culture and management of health care of the elderly which is very clear by comparing e.g. Sweden by New Zealand. It is now suggested that e.g. Sweden will be re-examining its elderly health care system as the COVID-19 pandemic (https://www.worldometers.info/coronavirus/) has shown that the health care of the elderly in Sweden need to be revisited. Though there are much worse infection and death rates in Europe and the USA, Sweden usually leads the world in innovation and improvements once that realize what goes wrong. The issue in Sweden is about that Sweden took a different path of tackling the COVID-19 as Sweden has generous space and landscape as the rest of the Nordic countries, so the citizens can whenever they want enjoy natural social distancing by escaping the tight urbanized centers of cities. It is rather that very high percentage of infections and deaths are taking place in the health care institutions of the elderly people. Hopefully, the rest of Europe and the USA need to revisit their living style and their elderly health care systems as well.