Professor of Pulmonology and Director of the Pulmonology Department of the University of Patras
Professor of Pulmonology and Intensive Care of the Medical School of National and Kapodistrian University of Athens
With the term “endemic disease” we describe an infection that appears permanently or frequently in a certain place and affects a given population, such as yellow fever in Africa and South America. That’s why there is a recommendation for vaccination against yellow fever before anyone travels to these countries. However, the endemic disease can be interrupted by outbreaks.
A characteristic example is perhaps the flu that affects the respiratory system. These have a seasonal character, as low temperatures favor the circulation of the corresponding flu viruses that cause them, such as simple coronaviruses that circulate among us annually. Thus, an epidemic disease can cause an outbreak at a certain period, as happens with the flu.
In 2018, according to data from the CDC, the flu caused 52,000 deaths in the United States, with a peak of 1,500 in one day. However, both the number of cases and the progression of the epidemic wave are easy to predict. Moreover, neither our way of life is seriously affected, nor is the health system so strained that it is difficult to serve the citizens who suffer from other illnesses.
Can something like this happen with the new coronavirus that afflicts us and when?
The first predictions, as unreliable as they may be, speak of an exit from the current stage of the pandemic at the beginning of summer and entry into a maintenance stage or a chronic stage of the pandemic, in which the severity of the disease caused by the virus will become increasingly weaker, increasingly mild, given the vaccination, as well as natural immunity.
If we take into account that 64% of the world’s population has been vaccinated with at least 2 doses of some vaccine, and the availability of vaccines, we need another 3-4 months with current rates to vaccinate 70% of the total population, given that only 14% of the poor / underdeveloped countries have been vaccinated. Together with half a billion people who have fallen ill and have survived, we reach a rate of about 75% of some degree of immunity.
Obviously, we will not all experience the end of this urgent phase at the same time, and in some countries the transitional period will be of longer duration compared to others.
In countries with lower vaccination coverage, especially in the vulnerable and elderly population (where scientific data show that three doses of the vaccine and now a fourth dose will be necessary), the urgent phase will affect them more for a longer time. For example, in our country, only 52% of the population has been vaccinated with three doses and there are three hundred thousand citizens over the age of eighty who are completely unvaccinated.
The future will include the provision of timely vaccines, which will include changes to the virus and thus provide longer immunity (6-12 months) and not 3-6 months as is the case today with existing vaccines designed for the initial virus that appeared in the city of Wuhan. Already, the timely vaccines are in the clinical trial stage and the results are expected soon. The difference in speed of the transition will also depend on the availability and accessibility of vaccines in each country.
This, in combination with the presence of anti-virus pills, which of course remain to be proven effective in daily life and not just through clinical studies, leaves a sense of cautious optimism, even if we need to go to a “frontal” war with the virus, that is, with an open economy and society. In this war, however, we will also need masks – to take our lives back – where there is a great deal of anxiety (MM).
This is the good scenario and assumes that a new, more virulent and concurrently more pathogenic strain of the virus will not be created, which will emerge from the underdeveloped-poor countries where vaccination coverage is particularly low. Moreover, such a thing is not evolutionarily advantageous for the virus, which in order to survive needs to be in a host (and therefore infect), but should not kill many of the people it infects, because the dead do not transmit!
From the magazine «Στα χρώματα του διαβήτη» (In the Colors of Diabetes), Issue 39, April-June 2022