Pandemic or Endemic? The Hamletic dilemma about the uncertain evolution of the Covid-19 Pandemic: the Role of Income Inequalities

Matteo Maria Cati

Adjunct Professor, Department of Economics, University of Bologna, Italy

*Corresponding author: Matteo Maria Cati, University of Bologna, 2 Scaravilli Square, 40126 Bologna, Italy.

Received: 05 November 2022; Accepted: 11 November 2022; Published: 16 November 2022

1. Introduction

The evolution of the COVID-19 pandemic, originating from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is under the close scrutiny of the World Health Organization (W.H.O.), whose Director General has recently stated [1] that:

• although the pandemic cannot be said to be over yet, we are presumably in its final phase;
• the only strategy that needs to be pursued is to continue the vaccination campaign to secure all the population and, in particular, health care workers and older individuals.

Many governments, such as the Italian government, are relaxing or even completely canceling the various emergency measures, and everyone is wondering when the COVID-10 pandemic will be downgraded to an endemic [2]. Is it too soon to do it? Even if the news on the pandemic is comforting, there are still reasons for uncertainty and concern.

This article raises two important questions:

• is Omicron, the SARS-CoV-2 Variant of Concern (VOCs) [3] currently circulating, the last one?
• What factors can favor or vice versa disfavor the onset of new Variant of Concern (VOCs) and change the course of the events?

Tracking the evolution of the pandemic virus is of fundamental importance, given its recent devastating impact in terms of the number of infected individuals and victims, as shown in Table 1 worldwide and in Italy (as of November 1, 2022, the total population in Italy was 59,037,000 people, and the total population in the world was 7,922,312,800 people – U.S. Census World Population clock https://worldpopulationreview.com/). Table 1 also shows the data on the vaccination campaign (number of people vaccinated with at least one dose and number of completed vaccinations):

Table 1: Number of infected individuals, number of deaths, number of doses of the vaccine as of November 1, 2022 in Italy (source: Istituto Superiore di Sanità – links: https://www.epicentro.iss.it/en/coronavirus/sars-cov-2-dashboard and (vaccines) Italian Government website https://www.governo.it/it/cscovid19/report-vaccini/) and worldwide (source: World Health Organization – link: https://covid19.who.int/)

At first glance, it can be noticed that (as of November 1, 2022):

In Italy, whose overall population is 59,037,000 individuals:

• the number of infected individuals (23,325,837) corresponds to more than 39.5% of the overall population;
• the number of deaths (175,318 individuals) accounts for approximately 3% of the overall population and 0.7% of the infected individuals;
• the number of people vaccinated (with at least one dose) (50,846,155) corresponds to 84% of the population, while the number of completed vaccinations (47,970,350) corresponds to 79%.

In the world, whose overall population is 7,922,312,800 individuals:

• the number of infected individuals (622,389,418) corresponds to more than 7.85% of the global population;
• the number of deaths (6,548,492 individuals) accounts for approximately 083% of the overall population and 0.10% of the infected individuals;
• the number of people vaccinated corresponds to 68.1% of the population, while the number of completed vaccinations to 62.5%.

More in depth:

• in Italy, 8,190,845 individuals, mainly belonging to the so-called ‘no vax’ population, corresponding to approximately 16% of the total Italian population, have yet to get vaccinated. The impact of the so-called no-vax people (whose decision of not getting vaccinated is often due to low levels of educational attainment, to a low income level, to government mistrust, and to other aspects such as political attitudes) [4] on the evolution of the pandemic may be significant. On this issue, the World Health Organization (W.H.O.) has in fact indicated vaccine hesitancy [5] as one of the ten major threats to global health [6].
• however,9% (2,527,217,783 individuals) of the worldwide population, including Italy, is completely unvaccinated, showing that vaccines are unfortunately still unequally distributed to the detriment of low-income countries. In particular, in 22 African countries [7], fewer than 40 out of 100 people in the population have received a dose of the vaccine.

Can these data give us some hints on how to answer the previous questions?

2. The SARS-CoV-2 virus and its Current Trend

The answer to the first question is rather obvious and intuitive: there is no certainty that Omicron is going to be [8, 9] the last Variant of Concern (VOCs). The answer to the second question is not simple at all. The retrospective study of the recent evolution of the virus shows that the emergence of new variants has had a certain regularity (every few months), and how a new variant becomes a Variant of Concern remains an open and unsolved question [10, 11]. Is there anything that governments and health authorities can do to minimize the risk of the onset of new variants and facilitate the transition of COVID-19 from pandemic status to epidemic status?

This is quite an important issue since Omicron, the most recent Variant of Concern (VOCs), accounted [12, 13] after February 2022 for over 98% of viral sequences shared on GISAID [14]. It has proven to be highly transmissible and to have weakened the capacity of vaccines to prevent the infection so much so that various pharmaceutical multinationals (such as Pfizer, BioNtech and others [15]) have recently decided to update their vaccines to target the Omicron variant and its mutations. For this reason, one strategy might be to determine what conditions favored the rise of Omicron (also known as Pango Lineage B.1.1.529). There are different theories about where Omicron came from [16] and why no one has been able to identify its origin, such as how researchers in sequencing hundreds of millions of genomes could have missed a set of mutations that led to the rise of Omicron; that Omicron evolved during chronic long term Covid-19 infections within single individuals or that Omicron emerged in different animal hosts with respect to the ones usually considered and others. Unfortunately, thus far, there is no evidence in favor of any of the theories. However, even if there is not a clear answer, the proposed theories have a common denominator, that is, they all refer to the possibility of an unobserved evolution (for example, in a geographical area with no sequencing capacity) of the virus, considering that the collected data of the GISAID database represents less than 1% of the sequenced genomes of SARS-CoV-2 among the overall reported cases of COVID-19 in Africa, Asia and the United States. In other words, the data collected to date represent an infinitesimal part of the mass of information available, and much work needs to be done.

Table 2: Variant of Concern (VOCs) – (source: World Health Organization – Tracking SARS-CoV-2 variants. Available at the link: https://www.who.int/activities/tracking-SARS-CoV-2-variants

A different and perhaps more rewarding strategy [17] could be to identify where the previous and the current Variant of Concerns were first detected - see Table 2 - and thereafter to study if there are environmental and/or human factors that have facilitated their onset. SARS-CoV-2 is an extremely pathogenic and highly transmissible coronavirus that has materialized through zoonotic spillover events, such as those occurring in the Huanan Seafood Wholesale Market in Wuhan [18], China, believed to be the early epicenter of the COVID-19 pandemic in 2019. A similar spill-over event from animals to humans of the so-called SARS-CoV-1 coronavirus (giving rise to a much less lethal disease) occurred in China [19] in November 2002 in Guangdong Province, showing that there was an animal reservoir (with an increasing number of species involved in the contagion) for SARS coronavirus.

Historically and similarly with respect to the ongoing COVID-19 pandemic, most of the known pandemics, such as influenza, and of the recent epidemics, such as Ebola and Zika, are zoonoses [20, 21] i.e., they have been caused by the ‘spill over’ [22, 23] of microbes of animal origin, or to other animals that can serve as intermediate hosts, to humans due to interactions among wildlife, livestock and people. Furthermore, being an RNA virus, SARS-CoV-2, similar to other viruses of this type, tends to adapt to its new human hosts with the development of mutations over time, resulting in the appearance of multiple variants that may have different characteristics than its original strains. As we saw, some of these variants, namely, the so-called Variant of Concern (VOCs), can present concerning characteristics in terms of perniciousness, vaccine resistance, contagiousness and virulence, so much so that they represent an increasing risk for public global health. It is therefore of fundamental importance to trace and monitor the emergence of new variants and sub variants. As a recent study states, there are factors that seem to favor the onset of new variants [24]:

”emergence of new variants has been due to multiple predisposing factors, including molecular characteristics of the virus, geographic and environmental conditions, and the impact of social determinants of health that favor the genetic diversification of SARS-CoV-2 in the world”.

Figure 1: Planisphere and Covid-19 variants

If we now notice that most of the Variants of Concerns (V.O.C)s - Table 2 - thus far have been detected in developing countries (see Figure 1 - for example, in 2020 the Delta variant (PANGO lineage: B.1.617.2) [25-27] was first detected in India and the variant Gamma (PANGO lineage P.1) was first detected in Manaus, the capital of the Amazonas state, and in a few months it spread to other Brazilian states, particularly in the southeastern region [28-30]. In 2021, the Omicron variant (also known as PANGO lineage B.1.1.529) [31-33] was first detected in South Africa and Botswana), it is intuitive to think that the complex system consisting of territoriality, environmental and economic conditions, human habits and, in particular, promiscuity with fauna, hygienic habits and eating habits, absence or inefficiency of the health system, unfortunately may become synonymous with diseases and the emergence of pandemics.

3. Ecosystem, COVID-19 and Income and Health Inequalities

There is a word that well represents and simplifies the complexity inherent in the study of pandemics, such as COVID-19, and epidemic diseases that have a zoonotic origin (i.e., caused by the ‘spill over’ of microbes of animal origin to humans), which is the word ‘interconnection’. Intuitively, any human activity that affects those interactions between the animal and the human world, such as increasing wildlife trafficking (see, for example, what has happened in the Chinese Wuhan Market), loss of biodiversity [34] (caused, for example, by tropical deforestation as in the Amazon rainforest) [35], environmental and climate changes, may become a source of danger.

Furthermore, as the literature on the transmission of SARS-CoV-2 suggests, the ‘spill over’ of microbes is bidirectional, not only from animal to human (zoonotic) but also from human to animal (zooanthroponotic). Spillback of the SARS-CoV-2 virus from humans to domestic and wild animals is well known in the literature on the topic [36-40]. Therefore, it is plausible to think that, in the complexity of the various ecosystems, there might be a triple ‘spill over’ effect of the mutated virus from animal species to humans, from humans to animal species and then back from animal species to humans, increasing the probability of the onset of new variants.

As a result, it is plausible to think that there is a strict relationship between human activities that disrupt the ecosystem and the likelihood of the development of pandemics and other infectious diseases of zoonotic and/or zooanthroponotic origin, particularly in geographic areas, such as Brazil, African nations and China, where there are human habits that encourage promiscuity with fauna, such as hygienic habits and eating habits that facilitate close contacts between humans and many animal species. Equivalently, the global ecosystem that by its nature should be a riskless asset becomes a risky ecosystem because of most human activities (pollution, resource depletion and so on). However, what can we do to handle a risky asset such as an already disrupted ecosystem? First, it is necessary to change worldwide governance toward more ecofriendly behavior. However, this change requires a strong global and intergenerational commitment that has years, if not decades, to go.

In another recent statement [41], the Director General of the World Health Organization (W.H.O.) once again stated that the only strategy to address the spread of the pandemic and the onset of new variants is vaccination of the global population. Unfortunately, as a consequence of within and across countries’ income and health inequalities and in particular poverty, vaccines [42-46] are unevenly distributed across countries. While the complete vaccination rate of the population of high-income countries (North America, Western Europe, Japan and China) is more than 70%, thus far (as of December 31st, 2021), less than 50% of the population of low-income countries has received the vaccine (in particular, the complete vaccination rate is below 10% in more than fifteen countries in Africa). The urgent need to find a remedy for vaccine inequality [47, 48] has become an even more relevant topic in the still ongoing ‘pandemic era’, since such a situation may slow the economic recovery and threaten the development and diffusion of new variants within the unvaccinated fraction of the world population and, as a consequence, spread over the already vaccinated population [49].

In other words, income inequalities, exacerbated by the COVID-19 pandemic [50], as well as inequalities in the quality of health systems (if any) within and across countries, not only in EMDE (Emerging Markets and Developing Economies) countries [51] but also in Europe [52], can make a difference in terms of the number of individuals vaccinated. People in low-income countries do not get vaccinated not because they do not want to but because in their countries or regions, vaccines are not yet available, there are no health systems or, if there are any, they are very weak. In other words, people who live in EMDE countries have a lower probability of getting vaccinated and, as a result, a higher probability of dying of COVID-19. Furthermore, as an intuitive result [53-55], there is a positive correlation between low vaccination rates and GDP growth rates: low vaccination rates imply low GDP growth rates.

4. Conclusions

Territorial economic conditions are an important key element in explaining the uncertain evolution of the COVID-19 pandemic and the difficulty of solving the ‘to be or not to be’ (pandemic or endemic) Hamletic dilemma. If we consider simultaneously the likely zoonotic and zooanthroponotic origin of the mutations of the virus together with the problem of vaccine inequity, due to economic and health inequalities, the disruption of the global ecosystem as a consequence of human activities, and the ease of spread due to the globalization of international movements of people, we can easily identify fertile soil for the onset of new variants.

The fact that the least vaccinated part of the world is made up for the most part by low-income countries (and in particular subtropical and tropical areas such as Africa, Asia and Latin America (in particular Brazil)) leads to some relevant consequences and obstacles to the transition of COVID-19 from a pandemic to an endemic disease, which is also due to the characteristics of the SARS-CoV-2 virus from which it originates.

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