[COVID-19] "No fever, but coughing..." COVID-19 resurgence, 'these symptoms' differ from before

The symptoms of COVID-19 have changed again compared to before.

I think it would be good for you to know.

Everyone, please be careful of COVID-19~

Even with decreased severity, 1 in 5 people in their 80s die.

Professor Kim Woo-joo of the Department of Infectious Diseases at Korea University Guro Hospital states, "It is true that the risk has decreased compared to the early stages of the COVID-19 pandemic." He explains that social immunity has been established through multiple COVID-19 vaccinations, and the virus itself has weakened through mutations.

The Korea Disease Control and Prevention Agency reports that the fatality rate for KP.3 in this re-emergence is in the 1% range. This is similar to the fatality rate of influenza (the flu). In contrast, during the 2020-2021 COVID-19 original virus (Wuhan strain) and Delta variant periods, the fatality rate reached 5-6%.

However, Professor Kim advised that this figure should be interpreted differently depending on age groups. According to the Korea Disease Control and Prevention Agency, the COVID-19 fatality rate for those in their 20s to 40s is only around 0.01%, but it rises sharply to around 0.1% starting from the elderly in their 60s. In particular, for those aged 80 and above, it increases to over 1.75%.

Professor Kim said, "A fatality rate of 0.1% means 1 in 1,000 people, and 1.75% means 1 in 50 people die, which are still alarmingly high figures." He added, "For high-risk groups such as the elderly or those with underlying health conditions, it's not yet at the level of saying 'it's just a cold or flu, nothing serious,' or 'it will naturally heal.'"

Currently, there is a lack of research on the severity and fatality of KP.3, so we must wait for official announcements from the World Health Organization (WHO) or health authorities. The same applies to information about major symptoms or long-term complications.

In fact, there are some differences in the main symptoms of this re-outbreak as described by university hospitals and outpatient clinics. The common observation is that general cold symptoms such as cough are prominent, but opinions differ regarding fever symptoms. This needs to be considered in light of the difference between outpatient clinics, which mainly see mild cases, and tertiary hospitals, which treat severe cases.

Strong cough without fever... beware of complications such as pneumonia

Professor Kim Woo-joo, who practices at a tertiary general hospital, said, "Among the patients visiting the hospital, those without a fever are the majority," and added, "Instead, symptoms such as cough, sore throat, and runny nose are more prominent." He explained that the loss of taste or smell, which was a major symptom before, is now rarely observed, and mild neuralgia symptoms are also occasionally seen.

On the other hand, a medical staff member at a private clinic said, "It is similar to common cold or severe flu symptoms," and added, "Since many patients are experiencing coughs or high fevers with this variant, monitoring symptoms is important." They also advised, "If high fever or cough does not subside within 3 to 4 days after taking prescribed cold medicine, you should undergo tests such as chest X-ray or auscultation to check for pneumonia."

In the medical community, there is still speculation about the long-term symptoms of this mutation, such as 'Long COVID,' and related complications. Currently, since cough symptoms are prominent in infected patients, pneumonia is the most concerning complication at this time.

In the outpatient setting, it was advised to be particularly careful that symptoms may progress due to pneumonia complications during this COVID-19 outbreak. It was especially emphasized that the elderly, patients with underlying conditions such as hypertension who are taking antihypertensive medications, and smokers should be cautious about pneumonia worsening. Due to the characteristics of the COVID-19 virus, some patients taking antihypertensive drugs (ACE inhibitors) may experience accelerated worsening of infection symptoms, such as virus transmission and vascular damage.

Professor Kim also explained, "Although the severity of KP.3 has decreased, in high-risk groups, there is still concern about respiratory complications such as pneumonia or respiratory failure, similar to influenza." However, Professor Kim added, "Long COVID refers to symptoms, syndromes, or complications that persist even three months after infection, so it is still premature to make a definitive judgment about this outbreak since it has not yet passed three months." He further stated, "Various types of COVID-19 complications have been reported, including neurological paralysis, gastrointestinal dysfunction, blood clots, and cardiovascular diseases such as myocardial infarction, so it is necessary to observe over time."

✔️Strong transmissibility + summer vacation season outbreak... Chuseok holiday could be a critical point

The more serious issue than severity is the strong transmissibility of the KP.3 variant. A recent study in the United States found that the transmissibility of KP.3 was 1.22 times higher than that of the JN.1 variant. This means the infection rate is 22% faster. This is because three additional mutations (S protein) in the JN.1 variant have increased its immune evasion ability.

Professor Kim explained, "Currently, when patients with cold symptoms visit the hospital and are tested, nine out of ten cases come back positive," adding, "The spread within nursing homes is increasing, and even medical staff at university hospitals are gradually becoming infected."

The current positive rate (infection rate) among patients who recently visited the hospital with acute respiratory symptoms is 43.5%. When limited to the 50s and 60s age group, the positive rate exceeds 60%. Since the positive rate during the winter outbreak in February was around 21%, this indicates that the scale of the outbreak is more than twice as large.

Some believe that the current trend is similar to the spread when daily confirmed cases reached 150,000 in the past. This is because the number of hospitalized patients has increased nearly 15 times in the past five weeks.

The quarantine authorities expect the peak of COVID-19 spread to occur by the end of this month. Based on the current trend, it is estimated that the number of infected patients per week could reach around 350,000.

Professor Kim was concerned that the end of August and mid-September, during the Chuseok holiday, could be a 'crisis point.' In previous outbreaks, the spread started in elementary, middle, and high schools and then extended to adults, but this time, the outbreak's peak coincided with the summer vacation period of frontline schools for the first time. Currently, there are no social distancing rules in place, and the unusually hot weather makes it easier for infectious diseases to spread in the '3M' environments (enclosed, crowded, close-contact), which is also a negative factor.

Professor Kim said, "This time, the outbreak is starting primarily among adults in their 20s to 40s and then spreading to the elderly and to elementary, middle, and high schools after the school reopening," and he assessed, "The Chuseok holiday overlaps with this period, which could potentially prolong the outbreak."

Professor Kim stated, "The main issue is 'COVID-19 insensitivity,' where most people do not get tested even if they have symptoms." He recommended, "Individuals should adhere to infection prevention guidelines, and health authorities should accurately communicate COVID-19 infection information. Additionally, efforts should be concentrated on administering treatments to high-risk groups and promoting vaccination."

Choi Ji-hyun jh@kormedi.com