The transmission of SARS-CoV-2 is increasing in many countries and in Greece. The fast-spreading Eris sub-variant of the Omicron “family” is being closely monitored by the WHO, while in recent days another new variant that appeared in Israel and Denmark (BA.2.86) has caught the attention of experts. because it carries many new mutations (more than 30).

Due to the evolving epidemiology of Covid-19, adherence to the vaccination schedule is essential to protect those at high risk for severe illness and death. Countries should assess their readiness to identify target groups and conduct timely vaccination campaigns against Covid 19, international organizations say.

New updated vaccines targeting the Omicron sub-variants will be available in the US in late September and in our country it is expected in mid-autumnTheodora Psaltopoulou, pathologist, professor of Epidemiology and Preventive Medicine, EKPA School of Medicine, reports to APE-MPE.

He adds that it will be optionally, while to date there are no new recommendations. According to the latest recommendations, the most vulnerable groups benefit from the updated vaccinations, mainly the elderly and those with health problems. At the same time, available antiviral drugs are still effective.

The possible scenarios for the evolution of Covid in the winter

In the prestigious scientific journal BMJ (British Medical Journal) an article was published on August 15 on the topic “Covid is on the rise again- so what next?” (Covid is on the rise again – so then what?), which records the rise in Covid cases in Great Britain, since early July 2023, with daily hospital admissions with Covid increasing. The variants currently growing in the UK are still sub-variants of Omicron and in themselves don’t look like they’ll make much of a splash.

However, nearly all people under the age of 50 have not been vaccinated in the past 18 months, and most people under the age of 75 have not been vaccinated for at least a year, the researchers report. Protection from previous contamination has also decreased, due to the absence of a large wave for several months. It is therefore possible, according to the article, that this wave is hitting a more susceptible population and may cause a large wave in September, combined with the return to school, work and staying indoors, where the virus spreads more easily.

As Ms Psaltopoulou reports, given protection from vaccines and previous infections, it is unlikely that this wave will cause a large increase in hospital admissions or deaths. However, any increase in the burden on hospitals is an issue, as are the effects of long Covid (e.g. due to persistent fatigue), as well as the removal of the sick from the workforce. The health system could also be strained next winter with the coronavirus, flu and respiratory syncytial virus that emerged last winter at almost the same time.

Updated vaccines in mid-autumn in Greece

Pfizer ( PFE.N )/BioNTech SE ( 22UAy.DE ), Moderna ( MRNA.O ) and Novavax ( NVAX.O ) all created new updated booster doses of their vaccines to target sub-variants of Omicron, such as XBB.1.5. EG.5 is similar to XBB.1.5, although the newer subvariant carries a mutation in the spike protein, the part of the virus that the vaccine targets.

The updated vaccines will be widely available in the US in the third or fourth week of September, while available antiviral drugs are still effective. In our country, the updated vaccines will come around mid-autumn and will be optional, while to date there are no new recommendations. According to the latest recommendations, the most vulnerable groups benefit from the updated vaccinations, mainly the elderly and those with health problems.

New variant of SARS-CoV-2 – The evolution of Eris

In recent days, according to the BMJ, another new variant appeared in Israel and Denmark (BA.2.86), which has attracted the attention of many experts because it has many new mutations. It is very likely that this new variant will also disappear, but it can serve as a reminder to intensify surveillance in the face of declining immunity, says Mrs. Psaltopoulou.

Covid infections and hospitalizations in the US and Europe are on the rise. The World Health Organization (WHO) has classified EG.5, also called “Eris”, as a “variant of interest”, indicating that it should be monitored more closely. However, the WHO points out that it currently does not appear to pose a greater threat to public health than other variants and that “there is no evidence of an increase in disease severity directly associated with EG.5”.

EG.5 had been found in more than 50 countries, according to the WHO. It is the most common and fastest-growing subtype of COVID-19 in the US, and accounts for over 17% of current Covid-19 cases, according to the CDC. In the US, the amount of the virus detected in sewage across the country, as well as the number of weekly Paxlovid prescriptions for the treatment of Covid, have increased significantly in the past month.

However, these numbers remain far below the hospitalization figures during the pandemic and do not indicate the need for social distancing measures or mask use, notes Ms Psaltopoulou.

The latest weekly respiratory infections epidemiological surveillance report of the National Public Health Organization (EODY), showed an increase in positivity and an increase in the number of hospital admissions for Covid-19. Eris went from 11% last week to 16%, according to the results of genomic analysis. Viral load surveillance in municipal wastewater showed an increase in SARS-CoV-2 virus circulation in 9 out of 10 areas tested.

What is the reason for the increase in incidents?

The incidents recorded by EODY, but also internationally, constitute a percentage of the total new incidents with Covid. This can be due to various reasons, for example:

Asymptomatic disease due to a genetic variant of the HLA complex, which up to 20% of individuals have. According to a recent publication in the scientific journal Nature “A common allele of HLA is associated with asymptomatic SARS-CoV-2 infection” (July 2023), these people have a positive test when they are sick, but do not show any symptoms.

Subclinical presentation, due to high vaccination coverage and previous illnesses with other subvariants of Omicron.

Mild symptoms (slight febrile movement, etc.) that quickly subside, cannot be differentially diagnosed compared to other viral infections, and do not lead the patient to undergo the corresponding diagnostic tests.

Vulnerable people should continue to be careful

The new variant is part of an expected evolution of the virus, Ms. Psaltopoulou notes. People, especially those who are most vulnerable to the virus (elderly and those with serious health problems), should continue to be more careful, because of the greater chance of severe illness. Also, when someone has been in contact with a sick person or has symptoms from the upper respiratory tract, it is recommended to do the corresponding test, Mrs. Psaltopoulou concludes.