Media reports say the new coronavirus is very contagious but less lethal than previous viruses. There are people, however, who show far higher mortality rates than others – elderly and/or those with underlying diseases.
Four medical experts gathered in a live Youtube show "Corona Fighters Live" last Tuesday to discuss why the new coronavirus is more lethal to these groups.
Italy reported 563 deaths from COVID-19 as of March 10, and their average age was 81. Twenty-four percent of Italy’s population is older than 65. Seniors with a weakened immune system are more vulnerable to the coronavirus in community infections. The number of infected elders increases more rapidly, and more of them tend to die from the virus than the younger generations would.
According to the World Health Organization and the Chinese Center for Disease Control and Prevention, the biggest risk factor is the old age combined with cardiovascular disease.
“The virus targets angiotensin-converting enzyme 2 (ACE-2) receptor to infiltrate into a cell. The old age and heart disease are considered as risk-factors because COVID-19 virus can target not only mucosa cells but also heart cells,” Myongji Hospital Laboratory Medicine Professor Lim Jae-gyun said.
The studies so far show that people who have had chronic lung disease, cardiovascular disease, kidney disease, diabetes, and those who are taking immunosuppressants after organ transplantation are vulnerable, she added.
The virus requires an ACE-2 receptor to enter into the cell. A research team led by Haibo Zhang published its study about COVID-19 using ACE-2, Lim noted.
Professor Lim also said that the COVID-19 virus has a relatively larger size. This explains why COVID-19 has a higher infection rate in the lower respiratory tract than the upper tract.
According to Myongji Hospital Professor Shin Hyun-young, cardiologists at the hospital recently discussed how to use ACE-2-targeting drugs for heart disease and hypertension.
Myongji Hospital Chairman Lee Wang-jun noted on the fact that a brief review comment on the journal Nature said that more clinical trials are necessary while confirming that there is a clear risk in the heart.
Lee went on to say that the underlying disease was an issue during the SARS outbreak, too, and it gradually drew more attention because a more statistically significant share of COVID-19 patients who suddenly died had had heart diseases.
“We are trying to make an analogy, though we do not have sufficient statistics or evidence to prove the exact correlation,” Chairman Lee said. “After consulting with our professors on such probability, we went as far as to conclude we could stop or change existing hypertension drugs such as ACE inhibitor or angiotensin receptor blocker (ARB).”
One of many types of blood pressure-lowering drugs is ACE-2 inhibitor. An early-stage study said COVID-19 might be associated with ACE-2 exists. Still, an explicit treatment guideline has yet to come whether patients who get the ACE-2 prescription need to take more caution or whether such prescriptions should be changed.
The experts agreed that patients who are taking high blood pressure medicines do not have to be overly anxious until researchers accumulate more and more explicit evidence. Patients with cardiovascular diseases might feel worried, given those with chronic lung diseases show poor prognosis when they get COVID-19. So far, however, they have only to cope with the spread by taking tests more actively, they said in conclusion.
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