Thursday, 19 March 2020

All you need to know about Corona Virus How it spreads, infects: Coronavirus impact comes into focus



Source: Pixabay.com
The medical impact of the new coronavirus is coming into sharper focus as it continues its spread in what is now officially recognized as a pandemic.

Its true fatality rate isn't yet known, but it seems 10 times higher than the flu, which kills hundreds of thousands around the world each year, the United States' top infectious disease expert told lawmakers last week.

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

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

There's still a lot that we don't know about the virus and disease it causes, COVID-19, he said.

How it spreads


Most spread is from droplets produced when an infected person coughs, which are inhaled by people nearby. Transmission from touching contaminated surfaces hasn't been shown yet, though recent tests by U.S. scientists suggest it's possible -- one 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 does not appear that there is a major risk of spread through sweat,'' said Julie Fischer, a Georgetown University microbiologist. The biggest concern about going to the gym is infected people coughing on others, or contaminating shared surfaces or equipment, she said. Consider avoiding large classes and peak hours and don't go if you're coughing or feverish, she suggests.

The risk of virus transmission from food servers is the same risk as transmission from other infected people, but ``one of the concerns in that food servers, like others facing stark choices about insurance and paychecks, may be pressured to work even if they are sick,'' she said.

How fast does it spread?


Each infected person spreads to two or three others on average, researchers estimate. It spreads more easily than flu but less than measles, tuberculosis or some other respiratory diseases. It is not known if it spreads less easily among 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 younger than 15.

What are the symptoms?


Most people get fever and cough, sometimes fatigue or shortness of breath, and recover after about two weeks. About 15% develop severe disease, including pneumonia, Chinese scientists reported from 45,000 cases there. Symptoms usually start slowly and often worsen as the illness goes on.

In a report last week on the first 12 patients in the U.S., seven were hospitalized; most had underlying health problems and got worse during the second week of illness.

In China, slightly more males have been diagnosed with COVID-19 than females, which might be because roughly half of Chinese men smoke but only 5% of females do, Frieden said.

Children seem to get less sick -- a report on 10 in China found that fevers tended to be milder and they lacked clear signs of pneumonia.

What does it feel like?


Some cruise ship passengers described symptoms similar to the common cold or flu. ``It's been a 2 on a scale of 10,'' said Carl Goldman, who was hospitalized in Omaha, Nebraska, after flying home.

However, a Chinese postgraduate student described going to the hospital twice after her symptoms worsened, and feeling ``a heavy head while walking, unable to breathe, and nauseous.

What's the test like?


The CDC recommends at least two swabs -- nose and throat. Samples are sent to labs that look for bits of viral genetic material, which takes roughly 4 to 6 hours. Altogether, it can take several days to ship a sample and get results back.

It's been taking two to three days, and ``we are working really hard to see if we can shorten that time`` by developing an in-house test, Dr. Aimee Moulin of the University of California, Davis said Thursday in a conference call held by the American College of Emergency Physicians.

Some areas have opened drive-thru sites for testing, which could reduce exposure to health workers and other patients or the public.

When is the virus most contagious?


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

Signs of virus also have been found in stool weeks after patients recover, but that doesn't mean it's capable of causing illness, scientists warn.

``The virus can be degraded,`` said Robert Webster, a St. Jude Children's Research Center virus expert. ``It's not necessarily infectious virus at all.

How deadly is it?


That won't be known until large studies are done to test big groups of people to see how many have been infected and with or without symptoms.

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

Flu kills about 0.1% of those it infects, so the new virus seems about 10 times more lethal, the National Institutes of Health's Dr. Anthony Fauci told Congress last week.

The death rate has been higher among people with other health problems -- more than 10% for those with heart disease, for example. In the U.S., 30 million have diabetes, more than 70 million are obese and nearly 80 million have high blood pressure.

Can infected people who recover get it again?


It's not known. A few reports from China say some people had COVID-19, recovered and then fell ill again. It's unclear if that's a relapse, a new infection, or a case where the person never fully recovered in the first place.

Scientists at the at the Fred Hutchinson Cancer Research Center in Seattle say the 30,000-letter genetic code of the virus changes by one letter every 15 days. It's not known how many of these changes would be needed for the virus to seem different enough to the immune system of someone who had a previous version of it for it to cause a fresh infection.

Fauci told Congress on Thursday that it was unlikely that someone could get reinfected. ``We haven't formally proved it, but it is strongly likely that that's the case,'' he said. ``Because if this acts like any other virus, once you recover, you won't get reinfected.''

Will it go away in the summer?


Flu fades each spring and the new virus may do the same, Fauci said last week in a podcast with a journal editor.

``I am hoping that as we get into the warmer weather we will see a decline that will give us a chance to get our preparedness up to speed,`` Fauci said. But that, too, is far from certain. ``We have to assume that the virus will continue to have the capacity to spread, and it's a false hope to say yes, it will just disappear in the summertime like influenza,'' said Dr. Michael Ryan, the World Health Organization's emergencies chief.

Flu viruses also mutate quickly, requiring new vaccines to be made each year. If the coronavirus follows suit, Frieden said, ``It could become a virus that circulates around the world for many years to come.

If I cross paths with a sick person, will I get sick, too?


You walk into a crowded grocery store. A shopper has coronavirus.

What puts you most at risk of getting infected by that person?

Experts agree they have a great deal to learn, but four factors likely play some role: how close you get; how long you are near the person; whether that person projects viral droplets on you; and how much you touch your face. (Of course, your age and health are also major factors.)

What's a viral droplet?


It is a droplet containing viral particles. A virus is a tiny codependent microbe that attaches to a cell, takes over, makes more of itself and moves on to its next host. This is its "lifestyle," said Gary Whittaker, a Professor of virology at Cornell University College of Veterinary Medicine.

A 'naked' virus can't go anywhere unless it’s hitching a ride with a droplet of mucus or saliva, said Kin-on Kwok, a professor at the Chinese University of Hong Kong’s Jockey Club School of Public Health and Primary Care. These mucus and saliva droplets are ejected from the mouth or nose as we cough, sneeze, laugh, sing, breathe and talk.

If they don’t hit something along the way, they typically land on the floor or ground. To get access to your cells, the viral droplets must enter through the eyes, nose or mouth. Some experts believe that sneezing and coughing are likely the primary forms of transmission. Kwok said talking face to face or sharing a meal with someone could pose a risk.

How close is too close?


Christian Lindmeier, a spokesman for the World Health Organization, said it’s best to stay 3 feet from a sick person. The Centers for Disease Control and Prevention said that standing within 6 feet could carry risk.

How long is too long to be near an infected person?


It’s not yet clear, but most experts agree that more time equals more risk.

Will you know a person is sick?


Keep in mind that if you do get sick, most symptoms are as mild as a cold or the flu. Still, others who are infected with coronavirus never fall ill at all. (Technically, COVID-19 is the name for the sickness caused by the respiratory virus.) But the flip side of this is that it can be hard to tell who is capable of spreading coronavirus.

In a growing number of cases, people without symptoms have infected others. The WHO still believes that most of those who have spread coronavirus were clearly ill at the time of transmission, Lindmeier said.

Can the virus last on a bus pole, touch screen or other surface?


After numerous people who attended a Buddhist temple in Hong Kong fell ill, the city’s Center for Health Protection collected samples from the site. Restroom faucets and the cloth covers over Buddhist texts tested positive for coronavirus.

Technically, the virus widely known as the coronavirus is just the latest of many similarly shaped viruses. A study of other coronaviruses found they remained on metal, glass and plastic for two hours to nine days. Whether a surface looks dirty or clean is irrelevant. If an infected person sneezed and a droplet landed on a surface, a person who then touches that surface could pick it up. How much is required to infect a person is unclear.

Coronaviruses are relatively easy to destroy, Whittaker said. Using a simple disinfectant on a surface is nearly guaranteed to break the delicate envelope that surrounds the tiny microbe, rendering it harmless. As long as you wash your hands before touching your face, you should be OK, because viral droplets don’t pass through skin.

Does the brand or type of soap you use matter?


No, several experts said.

My neighbor is coughing. Should I be worried?


There is no evidence that viral particles can go through walls or glass, said Dr. Ashish K. Jha, director of the Harvard Global Health Institute. He said he was more concerned about common spaces than dangers posed by vents, provided there is good air circulation in a room.

An infected neighbor might sneeze on a railing and if you touched it, "that would be a more natural way to get it from your neighbor," he said.

Can I get it from making out with someone?


Kissing could definitely spread it, several experts said. Though coronaviruses are not typically sexually transmitted, it’s too soon to know, the WHO said.

Is it safe to eat where people are sick with coronavirus?

If a sick person handles the food or it’s a high-traffic buffet, then risks cannot be ruled out - but heating or reheating food should kill the virus, Whittaker said. Jha concurred. "As a general rule, we haven’t seen that food is a mechanism for spreading," he said.

Can my dog or cat safely join me in quarantine?


Thousands of people have already begun various types of quarantines. Some have been mandated by health officials, and others are voluntary and primarily involve staying home. Whittaker, who has studied the spread of coronaviruses in animals and humans, said he’s seen no evidence that a person could be a danger to their pet.


Know More About Healthcare facilities in Thane Visit Thaneweb- Thane City Portal. For More Details Email us at - info@thaneweb.com





No comments:

Post a Comment