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Updated on June 22, 2022 8:24 pm
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Updated on June 22, 2022 8:24 pm
All countries
Updated on June 22, 2022 8:24 pm

Global Statistics

All countries
Updated on June 22, 2022 8:24 pm
All countries
Updated on June 22, 2022 8:24 pm
All countries
Updated on June 22, 2022 8:24 pm
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Why Is Covid So Contagious

How Long Will Protection From The Covid

Why Is The Coronavirus So Contagious?

Three studies released by the CDC in August 2021 suggest that the COVID-19 mRNA vaccines become less effective over time. The studies, all published in MMWR, show that vaccine protection against mild to moderate infection begins to drop beginning several months after the second dose. However, the vaccines continue to be highly protective against severe illness, hospitalization, and death.

The increase in mild and moderate breakthrough infections may not be entirely due to a decrease in the immunity provided by the vaccines. Its possible the vaccines are not as effective against the Delta variant as they were against previous variants. And safety precautions such as mask wearing and physical distancing have also decreased in the past several months. All these factors may play into increased breakthrough infections in fully vaccinated people.

The MMWR studies did not address the effectiveness of the Johnson & Johnson vaccine over time.

Is Climate Change Exposing Humans To More Viruses

Climate change can influence certain types of viral infections like West Nile, Tyler said. Some viruses are transmitted to people through vectors like mosquitoes or ticks.

When climate change causes longer seasons with higher temperatures or greater rainfall, mosquitoes can thrive and infection rates from viruses they carry can climb.

Wrong Beliefs Persist Despite Public Messaging

Chief investigator Dr Lisa Wynn, Associate Professor in Anthropology at Macquarie University, said the findings showed that despite clear public health messaging, people wrongly believed symptoms that they felt in their bodies or that other people could not see such as fever, muscle aches and chills did not render them contagious.

This was opposed to symptoms such as coughing, runny nose and sneezing, which they understood as expelling contagions from the body.

Dr Wynn said: What we are seeing from this current, apparently unstoppable wave of COVID spread is that the government efforts so far dont seem to be stopping the outbreak.

For sure they are limiting the spread and things would be much worse if they were not doing what they are doing but we have to ask, whats wrong? Whats missing here?

I think in that case it becomes important to start looking at cultural beliefs about contagion, about infectious disease and how it spreads and those cultural beliefs often do not coincide with what medical science knows or believes about contagion.

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Could A New Covid

Ray says that although experts in areas where the new strain is appearing have found an increased number of cases in children, he notes that the data show that kids are being infected by old variants, as well as the new ones. There is;no convincing evidence that any of the variants have special propensity to infect or cause disease in children. We need to be vigilant in monitoring such shifts, but we can only speculate at this point, he says.

Whats The Difference Between A Viral Infection And A Bacterial Infection Why Dont We Have Any Medications To Fight This New Coronavirus

WATCH LIVE: Gov. Phil Scott

Bacteria are living organisms. Antibiotics work to fight bacterial infections. And, there are broad-spectrum antibiotics that can fight numerous different types of bacteria. They serve as a magic bullet of sorts, Tyler said.

Unfortunately, anti-viral medications dont work that way. Each virus is different. And anti-viral medications work by targeting specific viruses.

We have drugs that help with AIDS, but they dont help with herpes, Tyler said.

Thats one of the reasons we have to get annual flu shots. The strain of the influenza virus that strikes each winter changes from year to year. So, each year, flu experts have to create a new vaccine based on the type of flu they predict will circulate that year.

Antibiotics dont work against viral illnesses like COVID-19.

Medical experts are racing now to develop vaccines for COVID-19. And, around the U.S. and the world medical providers are experimenting with anti-viral medications to see if any will help patients who have the new coronavirus.

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Are Humans Dealing With More Viruses Than In The Past

Viruses have always existed and they continually evolve and change, Tyler said.

Theyve always been common. As far as you go could back in human recorded history, you could have found viruses and viral infections, Tyler said.

But some of the viruses that have caused great harm to humans in recent decades including this new coronavirus and its predecessors, SARS and MERS have jumped from animals to humans. That was also true for the virus that causes AIDS.

These viruses frequently had niches in animals, Tyler said. As human behavior changes, whether its our dietary habits or growth of cities that push us into contact with things we werent previously in contact with, we get exposed to new viruses.

How Did The Coronavirus Start

The first case of COVID-19 was reported Dec. 1, 2019, and the cause was a then-new coronavirus later named SARS-CoV-2. SARS-CoV-2 may have originated in an animal and changed so it could cause illness in humans. In the past, several infectious disease outbreaks have been traced to viruses originating in birds, pigs, bats and other animals that mutated to become dangerous to humans. Research continues, and more study may reveal how and why the coronavirus evolved to cause pandemic disease.

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How Long Someone Can Spread The Virus


For both COVID-19 and flu, its possible to spread the virus for at least 1 day before experiencing any symptoms.


If a person has COVID-19, they could be contagious for a longer time than if they had flu.

Most people with flu are contagious for about 1 day before they show symptoms.

Older children and adults with flu appear to be most contagious during the initial 3-4 days of their illness but many people remain contagious for about 7 days.

Infants and people with weakened immune systems can be contagious for even longer.


How long someone can spread the virus that causes COVID-19 is still under investigation.

Its possible for people to spread the virus for about 2 days before experiencing signs or symptoms and remain contagious for at least 10 days after signs or symptoms first appeared. If someone is asymptomatic or their symptoms go away, its possible to remain contagious for at least 10 days after testing positive for COVID-19. People who are hospitalized with severe disease and people with weakened immune systems can be contagious for 20 days or longer.

Seeking The Achilles’ Heel Of The Virus

Why the New Coronavirus Variant May Be So Contagious

Scientists;know some;but not all of the reasons the new coronavirus;spreads so easily. Freeman points to several factors, including one that;distinguishes SARS-CoV-2;from the virus it closely resembles, Severe Acute Respiratory Syndrome .

SARS attacks the lower respiratory system, whose job it is to pull;in air from the upper respiratory system.

SARS-CoV-2, however, attacks the upper respiratory system, the pathway that allows air to travel;in and out of the lungs as;we breathe. The upper;airway is also the system involved when we cough.

The upper respiratory system offers a more efficient means of spreading, Freeman said.

“That’s why it is more transmissible. … When this emerged probably there was some mutation that adapted it to use the upper airway, and the upper airway has made it very successful.”

A second;difference between SARS and SARS-CoV-2;involves;the;bond that allows viral cells to attach to human cells and;infect them. With both viruses, this bond forms between the;Spike Protein on the virus and a region;on;the outside of the human cell called the ACE-2 receptor.

Both viruses use;this bond to enter cells,;but the bond is much stronger with the new coronavirus than it was with SARS. That is why many of the potential treatments so far are designed to;undermine;that bond.

“Flu viruses make six and a half times more mistakes than coronaviruses do,” Freeman;said.

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How Does The Coronavirus Spread

As of now, researchers know that the coronavirus is spread through droplets and virus particles released into the air when an infected person breathes, talks, laughs, sings, coughs or sneezes. Larger droplets may fall to the ground in a few seconds, but tiny infectious particles can linger in the air and accumulate in indoor places, especially where many people are gathered and there is poor ventilation. This is why mask-wearing, hand hygiene and physical distancing are essential to preventing COVID-19.

Symptoms & Emergency Warning Signs

People with COVID-19 have reported a wide range of symptoms from mild symptoms to severe illness. Symptoms may appear 2-14 days after exposure to the virus. If you have fever, cough, or other symptoms, you might have COVID-19.

Look for emergency warning signs* for COVID-19. If someone is showing any of these signs, seek emergency medical care immediately

  • Trouble breathing

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Are Coronavirus Variants More Dangerous

Bollinger says that some of these mutations may enable the coronavirus to spread faster from person to person, and more infections can result in more people getting very sick or dying.; In addition, there is preliminary evidence from Britain that some variants could be associated with more severe disease.

Therefore, it is very important for us to expand the number of genetic sequencing studies to keep track of these variants, he says.;

Bollinger explains that it may be more advantageous for a respiratory virus to evolve so that it spreads more easily. On the other hand, mutations that make a virus more deadly may not give the virus an opportunity to spread efficiently. If we get too sick or die quickly from a particular virus, the virus has less opportunity to infect others. However, more infections from a faster-spreading variant will lead to more deaths, he notes.

How Will New Variants Change the Nature of the Pandemic?

Why Is The New Coronavirus So Contagious And Spreading So Quickly Is There Something About It That Makes It A Super Villain Among Viruses Or Is It Just Behaving The Way Viruses Do

Asymptomatic Children Carry Higher COVID

What makes the new coronavirus so dangerous to humans is simply that its novel, meaning its new to humans, so we dont have any way to fight it.

This is the first time its ever circulated in humans, Pastula said.

So, the virus isnt more powerful, per se, than other viruses. But when it enters the human body, we have no pre-existing defenses since our bodies dont immediately recognize it as a dangerous intruder. Imagine an old, walled medieval town. If this virus were a disguised attacker arriving at the towns protective walls, but open gates, the guards would not immediately know to be suspicious. With this coronavirus, its as if the guardians of our cells have kept the gates open and let the coronavirus in without immediately recognizing its danger.

Then the virus starts to spread.

It gets in and hijacks the human cells machinery. Instead of the cell doing what its supposed to do, the virus overrides the cells normal programming and turns it into a machine to make more of the virus. It goes and goes and goes until the immune system stops it, Pastula said.

The virus is simply a blueprint or a code to turn cells into machines to make more virus, he said.

For a great visual explanation for how this coronavirus attacks cells, view these illustrations from the New York Times.

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What Is The Delta Variant

Since the beginning of the COVID-19 pandemic, the SARS-CoV-2 coronavirus that causes COVID-19 has mutated , resulting in different variants of the virus. One of these is called the delta variant. The delta coronavirus is considered a variant of concern by the CDC because it appears to be more easily transmitted from one person to another. As of July 2021, delta is regarded as the most contagious form of the SARS-CoV-2 coronavirus so far.

Here is what you should know:

The CDC recommends that everyone wait until they are fully vaccinated for COVID-19 before traveling internationally. Traveling internationally if you are not fully vaccinated for COVID-19 is not recommended, because it puts you at risk for coronavirus infection, including the SARS-CoV-2 delta variant. This includes unvaccinated children.

What Is The Connection Between The Johnson & Johnson Covid

In July 2021, the FDA warned that the Johnson & Johnson COVID-19 vaccine may lead to a small but increased risk of Guillain-Barré syndrome . GBS is a disorder in which the body destroys its own nerve cells. It can lead to muscle weakness and sometimes paralysis, trouble breathing, or, rarely, death. The risk of developing GBS after receiving the J&J vaccine is very low, and benefits of vaccination still far outweigh the risks.

The FDAs warning was based on preliminary reports of about 100 cases of GBS that occurred in people who had received the J&J vaccine. To date, about 12.8 million people in the US have gotten the J&J vaccine. Most of the reported cases occurred in men ages 50 years and older, about two weeks after vaccination.

Almost all required hospitalization because GBS can affect the nerves to chest muscles and the diaphragm, making it difficult to breathe. Most people recover completely from GBS within a few months, but some never regain full strength.

Seek immediate medical attention if you experience any of the following symptoms after receiving the J&J COVID-19 vaccine:

  • weakness or tingling sensations, especially in the legs or arms, thats worsening and spreading to other parts of the body
  • difficulty walking
  • difficulty with facial movement, including speaking, chewing, or swallowing
  • double vision or inability to move eyes
  • difficulty with bladder control or bowel function.

;for more new questions and answers.;;

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What Makes Covid Different From Sars

Those simulations revealed that the coronavirus strain causing COVID-19 is incredibly more stable than even the SARS virus. Researchers explain that the main reason coronaviruses dont usually spread rapidly is because their switches cant stay on long enough to attack large populations.

We discovered in these simulations that SARS-CoV-1 and SARS-CoV-2 have completely different ways of changing their shape, and on different time scales, Moradi says in a media release. SARS-CoV-1 moves faster, it activates and deactivates, which doesnt give it as much time to stick to the human cell because its not as stable. SARS-CoV-2, on the other hand, is stable and ready to attack.

Moradis team also noted a region at the tail of SARS-CoV spike proteins scientists have generally ignored in past studies. The study finds that piece plays a key role in the stability of these spikes. Mutations in the tail could also impact the viruss ability to infect people, the researchers warn. Learning more about how these switches work may also lead to a way of shutting down coronaviruses permanently.

We could design therapeutics that alter the dynamics and make the inactive state more stable, thereby promoting the deactivation of SARS-CoV-2. That is a strategy that hasnt yet been adopted, Moradi explains.

Researchers presented the findings at the 65th Annual Meeting of the Biophysical Society.

Are There Additional Covid

Why Is This Virus So Contagious?

Bollinger says that as of now, none of the new coronavirus variants call for any new prevention strategies. We need to continue doing the basic precautions that we know work to interrupt spread of the virus, he says.

Ray concurs: There is no demonstration yet that these variants are biologically different in ways that would require any change in current recommendations meant to limit spread of COVID-19, he says. Nonetheless, we must continue to be vigilant for such phenomena.

Ray stresses that both vaccination and human behavior are important. It is striking to note that 99% of COVID-19 deaths are now occurring in unvaccinated people, when most adults in the USA have been vaccinated, he says. The more people who are unvaccinated and infected, the more chances there are for mutations to occur. Limiting the spread of the virus through maintaining;COVID-19 safeguards; gives the virus fewer chances to change.;It also reduces the spread of more infectious variants, if they do occur.

Vaccines are the medical miracle of 2020, but we need to re-emphasize basic public health measures, including masking, physical distancing, good ventilation indoors and limiting gatherings of people in close proximity with poor ventilation. We give the virus an advantage to evolve when we congregate in more confined spaces, he says.

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What Are Breakthrough Infections And Why Do They Happen

A breakthrough infection is one that occurs after full vaccination.

In an article published in MMWR, the CDC reported 10,262 breakthrough infections through the end of April 2021. By that point, more than 100 million Americans had received the COVID-19 vaccine.

The vast majority of breakthrough infections were asymptomatic, mild, or moderate. About 1,000 people with breakthrough infections were hospitalized, and 160 died, though the hospitalizations and deaths were not always related to COVID-19.

These numbers tell us that the vaccines are doing a good job preventing infection and severe illness. None of the vaccines were 100% effective in clinical trials, so a small number of breakthrough infections was expected.

What About Other Mutations

While spike mutations have gained the spotlight, other mutations may also give SARS-CoV-2 variants an advantage.;

Other errors in the genetic sequence can help the virus make more copies of itself inside human cells.

“The virus just replicates;more actively and more aggressively,”;Professor Mackay said.;

But he also said there was more to learn about the effects of these mutations and whether they helped the virus stay one step ahead.;

“It’s still an open question as to how those other mutations interact and what role they play in creating variants that are more transmissible.”

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What Does This Mean For The Future Will We Ever Get Rid Of Covid

Infectious disease experts expect that COVID-19 will be sticking around. This virus is going to become part of our ecology, Dr. Sellick says. Our chance of getting rid of it was a year ago. We fumbled that terribly.

There is some hope, though: Dr. Adalja says that COVID-19 may simply become more like the common cold over time, becoming more prevalent during cold and flu season. New variants are also to be expected until a higher percentage of the countrys population is vaccinated, Dr. Sellick says. Thats why there may be a need for booster shots in the future.

We should be able to keep the pandemic in a place that wont cause the same levels of illness and death that weve been seeing, Dr. Sellick says. If we can keep people out of the hospital, thats a good thing.

To get to there, though, more people need to get vaccinated, even though its unclear if well ever reach herd immunity as mutations continue to develop.

For those of you on the fence, please get vaccinated, Dr. Swaminathan urges. Beyond protecting yourself, youll protect those around you, including friends, family, and those who are most vulnerable to serious effects from the virus.

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