"Severe COVID-19 cases continue to rise...infection control"

Joon Young Song, Professor of the Department of Infectious Diseases at Korea University Guro Hospital

Hospitalization and mortality risk continue among high-risk groups, such as immunocompromised and older adults

Safety of concurrent vaccination with a flu vaccine has been confirmed…immune boosting is sufficient

Joon Young Song, Professor of Infectious Diseases at Korea University Guro Hospital

More than two years after the COVID-19 pandemic transitioned to an endemic phase, the number of severe cases, particularly among high-risk groups, continues to occur steadily.

 

'The shadow of infection' remains in clinical practice.

 

While the number of confirmed cases is not surging as before, hospitalizations and severe cases are persisting, especially among vulnerable populations.

 

Joon Young Song, Professor of the Department of Infectious Diseases at Korea University Guro Hospital, said, "Many high-risk patients hospitalized with severe symptoms like pneumonia are confirmed with COVID-19." He added, "These patients face risks of prolonged hospitalization, deterioration of physical function, and death from severe infection." Professor Song also said, "Most patients hospitalized for pneumonia are elderly or immunocompromised, both high-risk groups.

 

Since recovery is slow and the possibility of complications is high, prevention through vaccination is essential." According to Professor Song, age is the most significant risk factor for COVID-19, with the risk of progression to a severe case increasing significantly with age in those 65 and older.

 

Immunocompromised individuals are at a very high risk of severe infection.

 

An analysis of vaccine efficacy and disease burden, conducted in the 'Host-based Influenza Morbidity & Mortality Study' involving eight medical institutions, including Korea University Guro Hospital, showed a high risk of COVID-19 infection and severe disease among immunocompromised patients, such as cancer patients and chronic kidney disease patients.

 

Dialysis patients are also classified as high-risk.

 

Since hospital dialysis rooms are confined spaces where multiple patients receive treatment, an infection can rapidly spread into an outbreak, with most cases carrying a high risk of progression to severe infection.

 

Experts are increasingly viewing COVID-19 as a seasonal respiratory illness, actively recommending vaccination and raising awareness of the disease.

 

Professor Song said, "In recent years, COVID-19 has shown a pattern of recurrent outbreaks twice a year, during summer and winter," and stressed, "The severe risk must be lowered through regular vaccination, just like with the flu." However, public awareness of the importance of vaccination has decreased as the endemic transition progresses.

 

According to Professor Song, even patients who absolutely need the vaccine, such as cancer patients, often hesitate due to concerns like 'Will I get a fever?' or 'Will it interfere with my anti-cancer treatment?' if their physician does not absolutely recommend it.

 

Professor Song emphasized that if a cancer patient contracts COVID-19 without being vaccinated, there is a high probability that their anti-cancer treatment must be suspended or that the infection will progress to a severe illness, such as pneumonia.

 

Professor Song assessed, "The preventive effect against severe infection remains over 70% and is maintained for about 10 months after vaccination.

 

For high-risk groups, such as the older adults aged 65 and over or those with underlying conditions like heart failure or lung disease, the priority is reducing hospitalization and death resulting from severe infection, pneumonia, acute respiratory illness, and the worsening of underlying diseases, rather than just preventing the infection itself." He also emphasized, "It is crucial for medical professionals to fully explain the necessity and safety of vaccination to patients and actively recommend it." "Safety of vaccination against COVID-19·flu at the same time, and the need to boost coverage" The government began the National Immunization Program (NIP) for both flu and COVID-19 vaccines on October 15.

 

Simultaneous vaccination of the two is possible.

 

This year's vaccine strain is LP.8.1 strain, a variant that began circulating last year.

 

Recently, sub-variants that have evolved from LP.8.1 strain, such as NB.1.8.1 strain and XFG strain, have been increasing.

 

Experts assess that, since these variants are sublineages of the Omicron lineage, the LP.8.1 variant vaccine provides sufficient protection.

 

Immunogenicity evaluation has confirmed a high level of cross-immunity against these sub-variants with the LP.8.1 vaccine.

 

Professor Song said, "As COVID-19 repeats its annual outbreaks, it is significant that the government has officially decided to support vaccination for the age groups and patient populations who absolutely require it." Pfizer received approval for its 'Comirnaty LP.8.1' vaccine targeting the LP.8.1 variant in August.

 

Notably, Pfizervaccine comes in a pre-filled syringe (PFS) formulation.

 

While multi-dose vials may have slight dosage errors, PFS offers the advantage of administering the correct, predetermined dose in a single-use syringe.

 

PFS is also considered safer in terms of infection control.

 

Professor Song commented, "The latest COVID-19 vaccines have confirmed sufficient preventive efficacy.

 

The currently circulating variant viruses do not have large mutational differences, so the vaccines introduced domestically can be expected to provide sufficient protection against the latest variants." He added, "Like the flu vaccine, the COVID-19 vaccine requires regular administration.

 

It is difficult to say which of the two diseases is more severe definitively, but both COVID-19 and influenza pose a high disease burden for those aged 65 and older." However, the COVID-19 vaccine initially had a lower vaccination rate than the flu vaccine, due to a perception that it was difficult to tolerate and caused many side effects.

 

While the influenza vaccination rate for those aged 65 and older currently reaches about 85%, the COVID-19 vaccination rate was 45% at the end of last year and 47.9% as of April this year.

 

Therefore, recommending concurrent vaccination of both is necessary to boost COVID-19 vaccination rates.

 

Professor Song explained, "The events after COVID-19 vaccine administration are a condition resulting from immune boosting.

 

However, from the third dose onward, the frequency and intensity of general adverse events, such as fever and fatigue, have decreased.

 

The incidence of myocarditis, which was a concern among young people, has also decreased significantly.

 

We believe that these concerns will gradually improve as COVID-19 vaccines are administered repeatedly." He also expressed that the safety of concurrent vaccination is not an issue.

 

He said, "Concurrent vaccination has not increased the frequency of adverse events, and no severe cases have been reported.

 

Various studies have all confirmed that simultaneous vaccination with the COVID-19 vaccine and the influenza vaccine is safe." Professor Song added, "Simultaneous vaccination plays an important role in increasing vaccination rates.

 

Administering both vaccines during a single visit prevents patients from missing their vaccination window.

 

In fact, a significant number of patients who received the COVID-19 vaccine did so simultaneously with the influenza vaccine." Finally, Professor Song said, "Academic societies are cooperating with the KDCA to continue communicating the necessity of the COVID-19 vaccine through various media and are continuing activities like campaigns." He stressed, "Misinformation or distorted reports related to vaccines, once spread, are often perceived as facts by the public and are difficult to correct.

 

Therefore, actively sharing accurate information and continuously educating and promoting the safety and necessity of vaccines is important."