Medical impact of coronavirus becomes clearer as experts’ research continues

The medical impact of the new coronavirus is becoming increasingly important as it continues to spread in what is now officially recognized as a pandemic.

Its true mortality rate is not yet known, but it seems 10 times higher than the flu, which kills hundreds of thousands of people worldwide each year, said the United States’ leading expert on infectious disease.

Most people have had mild to moderate illness and have recovered, but the virus is more serious for those who are older or have other health conditions.

That’s a huge number, said Dr. Tom Frieden, former director of the Centers for Disease Control and Prevention who now heads a global health organization. In the United States, 60% of adults have at least one underlying health problem and 42% have two or more.

“There is still much that we do not know about the virus and the disease it causes, COVID-19,” he said.

How it spreads

The spread is mainly from droplets produced when an infected person coughs, which are inhaled by people nearby. Transmission by contact with contaminated surfaces has not yet been demonstrated, although recent tests by American scientists suggest it is possible – a reason they recommend washing your hands and not touching your face. .

The virus can live in the air for several hours, up to 24 hours on cardboard and up to two to three days on plastic and stainless steel. Cleaning surfaces with solutions containing diluted bleach should kill it.

“While we are still learning about the biology of this virus, it doesn’t seem like there is a major risk of it spreading through sweat,” said Julie Fischer, microbiologist at Georgetown University. The biggest concern about going to the gym is that infected people cough on each other or contaminate shared surfaces or equipment, she said. Remember to avoid major classes and rush hours and don’t leave if you cough or have a fever, she suggests.

The risk of transmitting viruses from food servers is the same as transmission from other infected people, but “one concern is that food servers, like others, face difficult choices when it comes to food. insurance and paychecks can be forced to work even if they’re sick, “she said.

How fast is it spreading?

Each infected person spreads to two or three others on average, the researchers said. It is spread more easily than the flu but less than measles, tuberculosis or certain other respiratory diseases. It is not known if it spreads less easily in children, but fewer of them have been diagnosed with the disease. A study of 1,099 patients in China found that 0.9% of the cases were under the age of 15.

What are the symptoms?

Most people suffer from fever and cough, sometimes fatigue or shortness of breath, and recover after about two weeks. About 15% develop serious illness, including pneumonia, Chinese scientists have reported in 45,000 cases. Symptoms usually start slowly and often worsen during illness.

In a report last week on the first 12 patients in the United States, seven were hospitalized; most had underlying health conditions and worsened during the second week of illness.

Slightly more men in China have been diagnosed with COVID-19 than women, which may be due to the fact that about half of Chinese men smoke, but only 5% of women do, said Frieden. .

Children seem to get less sick – one in 10 reports in China found that fevers tended to be milder and that they had no obvious signs of pneumonia.

What does it look like?

Some cruise ship passengers have reported symptoms similar to colds or flu.

“This is a 2 on a scale of 10,” said Carl Goldman, who was hospitalized in Omaha, Nebraska, after returning home.

However, a Chinese graduate student described that she went to the hospital twice after her symptoms got worse and that she felt “a heavy head when walking, unable to breathe and nauseous”.

What does the test look like?

The CDC recommends at least two nose and throat pads. The samples are sent to laboratories that look for pieces of viral genetic material, which takes around 4 to 6 hours. In total, sending a sample and obtaining results can take several days.

It takes two to three days and “we are working very hard to see if we can shorten this time” by developing an in-house test, said Dr. Aimee Moulin of the University of California, Davis on Thursday in a conference call which held. by the American College of Emergency Physicians.

Some regions have opened driver-service sites for testing, which could reduce exposure of health workers and other patients or the public.

When is the virus most contagious?

The average time between exposure and the onset of symptoms is five to six days, but can be up to two weeks. Tests have found high amounts of virus in people’s throats and noses a few days before they show symptoms.

Signs of the virus were also discovered in the stool weeks after the patients recovered, but that doesn’t mean it is likely to cause disease, scientists warn.

“The virus can be degraded,” said Robert Webster, virus expert at the St. Jude Children’s Research Center. “It doesn’t have to be an infectious virus.”

How deadly is it?

This will not be known until large studies are done to test large groups of people to see how many have been infected and with or without symptoms.

Scientists have estimated the death rate from less than 1% to 4% among cases diagnosed so far, depending on the location.

The flu kills about 0.1% of those it infects, so the new virus seems about 10 times more deadly, said Dr. Anthony Fauci of the National Institutes of Health last week.

The death rate was higher among people with other health conditions – more than 10% for those with heart disease, for example. In the United States, 30 million have diabetes, more than 70 million are obese, and almost 80 million have high blood pressure.

Can infected people recovering from it?

It is not known. Some reports from China indicate that some people had COVID-19, recovered, and then fell ill again. It is not known whether this is a relapse, a new infection, or a case where the person has never fully recovered in the first place.

Scientists at the Fred Hutchinson Cancer Research Center in Seattle say the genetic code for the 30,000-letter virus changes by one letter every two weeks. It is not known how many of these changes would be necessary for the virus to appear different enough from the immune system of a person who had a previous version to cause a new infection.

Fauci told Congress Thursday that it was unlikely anyone could be re-infected.

“We have not officially proven it, but it is very likely to be the case,” he said. “Because if it acts like any other virus, once you recover, you will not be reinfected.”

Will it disappear in summer?

The flu clears up every spring and the new virus could do the same, Fauci said last week in a podcast with a newspaper editor.

“I hope that, as we enter the warmer weather, we will witness a decline that will give us a chance to prepare quickly,” said Fauci.

But that too is far from certain. “We have to assume that the virus will continue to have the ability to spread, and it is a false hope to say yes, it will simply go away in the summer like the flu,” said Dr. Michael Ryan, emergency chief of the ‘World Health Organization.

Flu viruses also mutate quickly, which requires the production of new vaccines every year. If the coronavirus follows suit, Frieden said, “It could become a virus that circulates around the world for many years to come.”