"BA.5 Has High Immune Evasion but Vaccine Remains Effective in Preventing Severe Cases and Deaths" (Update)

The Central Disaster and Safety Countermeasures Headquarters Announces Analysis of International Trends and Response Measures for Omicron Subvariants BA.4 and BA.5

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[Asia Economy Reporter Kim Young-won] The quarantine authorities emphasized that vaccination is effective in preventing severe illness and death even against BA.4 and BA.5, which have a high risk of reinfection.

On the 8th, the Central Disaster and Safety Countermeasures Headquarters analyzed and announced international trends and response measures regarding the Omicron subvariants BA.4 and BA.5.

Based on overseas studies, the authorities explained that BA.4 and BA.5 have higher immune evasion than BA.2. According to research conducted by teams from Harvard and Israel on 27 vaccinated individuals and 27 recovered patients, BA.4 and BA.5 showed neutralizing antibody formation 20 times lower than the original coronavirus and 3 times lower than the Omicron variants (BA.1 and BA.2). This means that even people with immunity from vaccination or infection are more susceptible to infection by BA.4 or BA.5.

However, despite the high immune evasion of BA.4 and BA.5, the authorities emphasized that the preventive effect of vaccination against severe illness and death remains valid. According to a report from the European Centre for Disease Prevention and Control (ECDC), the fourth dose of vaccination has proven to reduce the mortality burden and provide benefits for the elderly aged 80 and above. Son Young-rae, head of the Social Strategy Division at the Central Accident Response Headquarters, added, "Based on such analyses, major countries including the United States, Germany, and Japan are encouraging vaccination primarily for those aged 60 and above and people with underlying conditions."

Regarding the impact of these subvariants on severity or fatality rates, it has not yet been clearly identified, so the authorities are monitoring through epidemiological data analysis. Son said, "Although the proportion of BA.5 is increasing quite rapidly in cases from various countries, this has not been accompanied by increases in deaths or severe cases," adding, "There are predictions that the existing severity and fatality rates are similar or possibly somewhat lower."

BA.4 and BA.5 have been detected in a total of 62 countries as of last month. According to the World Health Organization (WHO), BA.5 accounts for 43% and BA.4 for 12% of new cases worldwide, with their share rapidly increasing. Consequently, COVID-19 cases are rising in countries including the United States. In particular, Europe saw a 33% increase in new cases over the week ending on the 26th of last month compared to the previous week.

The quarantine authorities plan to announce measures for vaccination and preparations against a resurgence on the 13th. Son stated, "It is clear that the current trend of confirmed cases has shifted from a decline to an increase," and added, "If it is judged to be a new resurgence, we are reviewing how to change the current quarantine response system, and we will explain the response plan at the Central Disaster and Safety Countermeasures Headquarters meeting next Wednesday (the 13th)."

This content was produced with the assistance of AI translation services.