The COVID-19 pandemic is on its wayalbeit slowly, running out worldwide and this trend is, so to speak, certified by the latest report of the World Health Organization (WHO) which, globally, recorded in the last 28 days, from January 9 to February 5, 2023, nearly 10.5 million new infections from COVID-19 and over 90,000 deaths, with a drop of 89% and 8% respectively from the previous 28 days. This reduction is present in all regions of the worldalbeit with some differences especially as regards mortality, even if it has been known for some time now that the number of deaths is the last parameter to decrease in the presence of a decrease in infections.
This new epidemiological situation has been well analyzed in an article (Wafaa M. El-Sadr and others) which predicts that in the future the SARS-CoV-2 virus will remain among usprobably still causing infections in many people, although certainly the worst phase is now behind us. For this reason, the need to avoid the use of alarmist language by experts is underlined but without falling into easy triumphalismsunderestimating the continuous circulation of the virus and at the same time offering valid and feasible solutions to get people used to experiencing this new non-emergency phase. The most recent epidemic resurgence of SARS-CoV-2 mainly involved China. In a study (Pan Y. and others) the variants of SARS-CoV-2 circulating in Beijing in the last period of 2022 were characterized, carrying out the epidemiological and phylo-genetic analysis of the isolated viruses. It emerged that the co-circulation of the BF.7 and BA.5.2 variants featured as early as November 14, 2022, the epidemic in Beijing and that there has been no evidence that new variants have emerged. This research, although carried out in Beijing alone, it probably represents a snapshot of what happened in Chinasince in this megalopolis there is a frequent exchange of population with the rest of the country and the circulating strains in themselves have a high transmissibility.
Throughout the world, economic problems have followed the evolution of the COVID-19 pandemic at the same pace in these three years. A study conducted in Bangladesh (Md Ruhul Amin and others), a country in which a series of preventive measures, partly restrictive and partly open, have been implemented, has highlighted the presence of wide fluctuations in the prices of poultry products (meat and eggs). The analysis, conducted in an area of intensive poultry farmingdemonstrated how there was a strong impact of the COVID-19 pandemic on the prices of the products in question, with an increase that in some moments was 40% for chicken meat and 30% for eggs. From this isolated experience, which has also found hospitality in a prestigious magazine, emerges the the need to provide financial support especially to small farmers and ranchers, to improve their resilience to shock situations such as the COVID-19 pandemic and natural disasters. There correct and early diagnosis of SARS-CoV-2 infection cases great importance in terms of public health, as the rapid emergence of new SARS-CoV-2 variants poses the constant challenge of updating tests to identify these variants as well. In a study (Supaporn Wacharapluesadee and others) a new diagnostic test is presented which demonstrates greater sensitivity than the previous ones and is also very flexible since, if necessary, it allows a series of modifications to be made, so as to also identify the new variants.
The ability to protect against the Omicron BA.2.75 sub-variant, was analyzed in Qatar, studying the effect of a previous SARS-CoV-2 infection on reinfection (Chemaitelly H et al). The results showed that a previous infection with a pre-Omicron variant confers negligible protection, thus confirming that in these cases post-infection immunity does not last more than a year. The protection conferred by a previous infection with an Omicron variant is better and equal to 50%when the previous infection was due to subvariants BA.1 and BA.2 and 80% when the infection was more recent, i.e. caused by the BA.4 and BA.5 variants. In the case of a combined pre-Omicron and Omicron infection, this conferred greater protection against the BA.2.75 infection.
The protection conferred by the IgA class immunoglobulins directed against SARS-COV-2 present on the mucosa, it has been the subject of a study (Marking U and others) which has shown that this lasts up to 7-8 months. This result indicates the key role played by local immunity which is present on the mucous membranes of the upper airways and indirectly underlines the importance that a vaccination carried out using a nasal and/or oral vaccine capable of inducing a response of this type may have. An interesting study (Cassandra Willyard) critically analyzed the results of several researches which were all focused on the duration of immunity against COVID-19. It is interesting to note that on this aspect there are clear differences between the current Omicron era compared to previous waves caused by pre-Omicron variants. Furthermore, the growing percentage of hybrid immunity globally and the ever-increasing number of people protected by the vaccine, when combined, will be able to influence the development times and peaks of infection, although it is not yet clear in what way.
A possible future epidemiological scenario could therefore follow the well-known one of the flu: with the need to subject to frequent boosters only people at high risk of developing severe forms of COVID-19, while younger individuals, with no risk factors, may themselves have significant protection, such as not to require further boosters . A recent research (Satoshi Mizuta e altri) has taken up a theme that at the beginning of the pandemic was the subject of numerous studies: this is the role of chloroquine derivatives in the treatment of SARS-CoV-2 infection. This new study, conducted in vitro, analyzed the effect on SARS-CoV-2 of various chloroquine derivatives and it resulted that some of these, in addition to having an efficacy against Plasmodium falciparum, responsible for severe malaria, also have some efficacy on the virus responsible for COVID-19. Naturally these results, although interesting in themselves, should not find any application in the treatment of COVID-19 at least at the moment.
The Italian studio TREASURE (Brambilla M. and others), which involved 368 subjects, 161 of whom vaccinated with adenoviral vector vaccines (AstraZeneca or Janssen) and 207 with mRNA vaccine (Pfizer or Moderna), demonstrated that the four COVID-19 vaccines induce a transient inflammatory response, without this resulting in significant platelet activation. Modest alterations in the activation of coagulation and endothelial function at the level of blood vessels could be responsible at the general population level for the very rare thromboembolic complications observed after vaccination. The early treatment of more than 933 COVID-19 outpatientsmainly vaccinated, treated with a single dose of interferon, showed that the incidence of hospitalization and access to the Emergency Department was significantly lower in treated patients than in untreated ones (Reis G. and others). This result, if confirmed by further studies with a higher number, could pave the way for the use of interferon in therapy, the use of which, among other things, would also be motivated by a production deficit of this molecule in COVID-19 patients, repeatedly described in recent years. A research conducted in 50 patientstreated with molnupiravir (Najjar-Debbiny R. and others), has shown that taking this antiviral drug significantly reduces the risk of severe COVID-19 and mortality, especially in older patients and in inadequately protected subjects from vaccination. A study, conducted between May 2021 and April 2022involved 75 children under the age of 18 suffering from multi-system inflammatory syndrome associated with SARS-CoV-2, of whom 37 treated with a cortisone (methyl-prednisolone) and 38 with intravenous immunoglobulin (Welzel T. and others) . It emerged from the results that cortisone treatment in children did not significantly influence the length of hospital stay hospital compared to immunoglobulins, although methylprednisolone could still be considered a first-line treatment of these patients. It has been stressed from many quarters that the frequent use of antibiotics in COVID-19as has occurred in these three years of the pandemic, represents a threat that can increase the antibiotic resistance of bacteria, which is already a serious public health problem.