India on Monday, 5 July, reported 39,796 new coronavirus cases, taking the tally in the country to 3,05,85,229. The death toll increased by 723 to 4,02,728.According to the Union Health Ministry data, there are currently 4,82,071 active cases across the country, while 2,97,00,430 patients have been discharged so far, with 42,352 discharges reported in the…
India on Monday, 5 July, reported 39,796 new coronavirus cases, taking the tally in the country to 3,05,85,229. The death toll increased by 723 to 4,02,728.
According to the Union Health Ministry data, there are currently 4,82,071 active cases across the country, while 2,97,00,430 patients have been discharged so far, with 42,352 discharges reported in the last 24 hours.
Much is left to learn about the coronavirus that is changing life as we know it, but our journey has already yielded many lessons. In late December 2019, reports emerged of a novel coronavirus outbreak connected with pneumonia cases at a wildlife market in Wuhan, China. COVID-19 spread across the nation within weeks—and then stormed…
Much is left to learn about the coronavirus that is changing life as we know it, but our journey has already yielded many lessons. In late December 2019, reports emerged of a novel coronavirus outbreak connected with pneumonia cases at a wildlife market in Wuhan, China. COVID-19 spread across the nation within weeks—and then stormed its way across the world. By March 11, the World Health Organization labeled COVID-19 a pandemic.
In the time since, we’ve learned some important basics about SARS-CoV-2, the novel coronavirus behind COVID-19—including how it spreads then invades the body and which parts of the world are currently facing serious outbreaks. Here are maps that illustrate its spread and answers to other key questions about COVID-19.
How many cases are there worldwide?
The coronavirus pandemic is reshaping the world. Here’s a closer look at the case counts and fatalities across the world.
Where are cases growing and declining in the U.S.?
The coronavirus is affecting U.S. regions in different ways. Here are the areas where cases and deaths are either decreasing or increasing the most, based on the last seven days compared to the previous week.
What is a coronavirus?
Coronaviruses are a large family of viruses, but only seven of its members infect humans. Four types cause minor illnesses like the common cold, while other coronaviruses have triggered far more devastating impacts such as SARS, MERS, and now COVID-19. Coronaviruses can be zoonotic, meaning they jump from animals to humans.
Like its relatives, COVID-19 is primarily a respiratory disease that starts in the lungs, causing pneumonia-like symptoms, but can also cast a storm across the entire body.
How does COVID-19 spread?
Like other respiratory diseases, COVID-19 primarily spreads through small droplets—saliva or mucus—that an infected person expels when they cough, sneeze, or talk. These droplets can travel three to six feet and remain infectious for anywhere from four to 48 hours, depending on the surface. (The virus may also spread via accidental consumption of fecal matter or aerosols, tiny particles that are mostly a concern in clinical settings.)
You can protect yourself from catching the virus by staying six feet away from others and washing your hands with soap and water for more than 20 seconds.
How long does it last on surfaces?
The virus lives longer on surfaces. Disinfectants that are at least 60 percent alcohol by volume can also kill the virus on plastic and stainless steel surfaces.
What does the coronavirus look like?
Coronaviruses get their name from their spiky structure. Like other coronaviruses, SARS-CoV-2 is spherical with spike proteins that look a bit like a corona, or crown.
How does SARS-CoV-2 invade the body?
Its spiky structure helps the coronavirus latch onto cells that it can invade. Once a virus enters the human body through the eyes, mouth, or nose, it looks for cells with its favorite doorways—proteins called receptors. If the virus finds a compatible receptor, it can invade and start replicating itself. For SARS-CoV-2, that receptor is found in lung cells and the gut.
How does age factor into the severity of the disease?
Currently, children with COVID-19 may be less likely to require intensive care and also have lower fatality rates than adults. The difference in severity is not yet fully understood.
What are the common diagnostic symptoms?
There isn’t a single diagnostic symptom, but some are more common:
What are the chronic conditions that put people at higher risk?
COVID-19 poses a particularly serious threat to people with underlying conditions such as cardiovascular disease, diabetes, chronic lung disease, high blood pressure, and cancer.
How do you diagnose the virus?
Testing is done to diagnose the presence of the virus. Swab samples taken from the nose or mouth are tested for the virus’s genetic material. Researchers are also developing protocols for tests using saliva and blood samples.
When will a vaccine be ready?
To develop immunity, vaccines may contain killed or weakened virus, viral proteins, or viral genetic material. The best strategy to use against SARS-CoV-2 is yet to be determined. It could take until January 2021—or perhaps much longer—before a vaccine is ready for public use.
See all of National Geographic’s coronavirus coverage.
Source: HMS COVID-19 Student Response Team, Education Committee
This illustration, created at the Centers for Disease Control and Prevention (CDC), reveals ultrastructural morphology exhibited by coronaviruses. Note the spikes that adorn the outer surface of the virus, which impart the look of a corona surrounding the virion, when viewed electron microscopically. A novel coronavirus, named Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2), was identified as the cause of an outbreak of respiratory illness first detected in Wuhan, China in 2019. The illness caused by this virus has been named coronavirus disease 2019 (COVID-19).
Illustration by Alissa Eckert, MS; Dan Higgins, MAMS/CDC
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Difference between COVID-19 & Flu Influenza (Flu) and COVID-19 are both contagious respiratory illnesses, but they are caused by different viruses. COVID-19 is caused by infection with a new coronavirus (called SARS-CoV-2), and flu is caused by infection with influenza viruses. COVID-19 seems to spread more easily than flu and causes more serious illnesses in…
Difference between COVID-19 & Flu
Influenza (Flu) and COVID-19 are both contagious respiratory illnesses, but they are caused by different viruses. COVID-19 is caused by infection with a new coronavirus (called SARS-CoV-2), and flu is caused by infection with influenza viruses.
COVID-19 seems to spread more easily than flu and causes more serious illnesses in some people. It can also take longer before people show symptoms and people can be contagious for longer. More information about differences between flu and COVID-19 is available in the different sections below.
Because some of the symptoms of flu and COVID-19 are similar, it may be hard to tell the difference between them based on symptoms alone, and testing may be needed to help confirm a diagnosis.
While more is learned every day about COVID-19 and the virus that causes it, there is still a lot that is unknown . This page compares COVID-19 and flu, given the best available information to date.
Overview Coronavirus Open pop-up dialog box Close Coronavirus Coronavirus Coronavirus is a family of viruses that can cause respiratory illnesses such as the common cold, severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). Coronaviruses are a family of viruses that can cause illnesses such as the common cold, severe acute respiratory syndrome…
Overview
Coronavirus
Coronavirus
Coronavirus is a family of viruses that can cause respiratory illnesses such as the common cold, severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS).
Coronaviruses are a family of viruses that can cause illnesses such as the common cold, severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). In 2019, a new coronavirus was identified as the cause of a disease outbreak that originated in China.
The virus is now known as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The disease it causes is called coronavirus disease 2019 (COVID-19). In March 2020, the World Health Organization (WHO) declared the COVID-19 outbreak a pandemic.
Public health groups, including the U.S. Centers for Disease Control and Prevention (CDC) and WHO, are monitoring the pandemic and posting updates on their websites. These groups have also issued recommendations for preventing and treating the illness.
Products & Services
Symptoms
Signs and symptoms of coronavirus disease 2019 (COVID-19) may appear two to 14 days after exposure. This time after exposure and before having symptoms is called the incubation period. Common signs and symptoms can include:
Early symptoms of COVID-19 may include a loss of taste or smell.
Other symptoms can include:
Shortness of breath or difficulty breathing
Muscle aches
Chills
Sore throat
Runny nose
Headache
Chest pain
Pink eye (conjunctivitis)
Nausea
Vomiting
Diarrhea
Rash
This list is not all inclusive. Children have similar symptoms to adults and generally have mild illness.
The severity of COVID-19 symptoms can range from very mild to severe. Some people may have only a few symptoms, and some people may have no symptoms at all. Some people may experience worsened symptoms, such as worsened shortness of breath and pneumonia, about a week after symptoms start.
People who are older have a higher risk of serious illness from COVID-19, and the risk increases with age. People who have existing medical conditions also may have a higher risk of serious illness. Certain medical conditions that may increase the risk of serious illness from COVID-19 include:
Serious heart diseases, such as heart failure, coronary artery disease or cardiomyopathy
Cancer
Chronic obstructive pulmonary disease (COPD)
Type 1 or type 2 diabetes
Overweight, obesity or severe obesity
High blood pressure
Smoking
Chronic kidney disease
Sickle cell disease or thalassemia
Weakened immune system from solid organ transplants
Pregnancy
Asthma
Chronic lung diseases such as cystic fibrosis or pulmonary fibrosis
Liver disease
Dementia
Down syndrome
Weakened immune system from bone marrow transplant, HIV or some medications
Brain and nervous system conditions
Substance use disorders
This list is not all inclusive. Other underlying medical conditions may increase your risk of serious illness from COVID-19.
COVID-19 self-checker
Assess your symptoms on CDC’s coronavirus self-checker tool and find out if you’re a candidate for a COVID-19 test.
When to see a doctor
If you have COVID-19 signs or symptoms or you’ve been in contact with someone diagnosed with COVID-19, contact your doctor or clinic right away for medical advice. Tell your health care team about your symptoms and possible exposure before you go to your appointment.
If you have emergency COVID-19 signs and symptoms, seek care immediately. Emergency signs and symptoms can include:
Trouble breathing
Persistent chest pain or pressure
Inability to stay awake
New confusion
Pale, gray or blue-colored skin, lips or nail beds — depending on skin tone
This list isn’t all inclusive. Let your doctor know if you are an older adult or have chronic medical conditions, such as heart disease or lung disease, as you may have a greater risk of becoming seriously ill with COVID-19. During the pandemic, it’s important to make sure health care is available for those in greatest need.
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More Information
Causes
Infection with the new coronavirus (severe acute respiratory syndrome coronavirus 2, or SARS-CoV-2) causes coronavirus disease 2019 (COVID-19).
The virus that causes COVID-19 spreads easily among people, and more continues to be discovered over time about how it spreads. Data has shown that it spreads mainly from person to person among those in close contact (within about 6 feet, or 2 meters). The virus spreads by respiratory droplets released when someone with the virus coughs, sneezes, breathes, sings or talks. These droplets can be inhaled or land in the mouth, nose or eyes of a person nearby.
In some situations, the COVID-19 virus can spread by a person being exposed to small droplets or aerosols that stay in the air for several minutes or hours — called airborne transmission. It’s not yet known how common it is for the virus to spread this way.
It can also spread if a person touches a surface or object with the virus on it and then touches his or her mouth, nose or eyes, but the risk is low.
Some reinfections of the virus that causes COVID-19 have happened, but these have been uncommon.
Risk factors
Risk factors for COVID-19 appear to include:
Close contact (within 6 feet, or 2 meters) with someone who has COVID-19
Being coughed or sneezed on by an infected person
Complications
Although most people with COVID-19 have mild to moderate symptoms, the disease can cause severe medical complications and lead to death in some people. Older adults or people with existing medical conditions are at greater risk of becoming seriously ill with COVID-19.
Complications can include:
Pneumonia and trouble breathing
Organ failure in several organs
Heart problems
A severe lung condition that causes a low amount of oxygen to go through your bloodstream to your organs (acute respiratory distress syndrome)
Blood clots
Acute kidney injury
Additional viral and bacterial infections
Prevention
The U.S. Food and Drug Administration (FDA) has given emergency use authorization to some COVID-19 vaccines in the U.S. A vaccine can prevent you from getting the COVID-19 virus or prevent you from becoming seriously ill if you get the COVID-19 virus. Also, if you are fully vaccinated, you can return to many activities you may not have been able to do because of the pandemic — including not wearing a mask or social distancing — except where required by a rule or law. If you are fully vaccinated and have a condition or are taking medications that weaken your immune system, you may need to keep wearing a mask.
If you haven’t had the COVID-19 vaccine, you can take many steps to reduce your risk of infection. WHO and CDC recommend following these precautions for avoiding exposure to the virus that causes COVID-19:
Avoid close contact (within about 6 feet, or 2 meters) with anyone who is sick or has symptoms.
Keep distance between yourself and others (within about 6 feet, or 2 meters). This is especially important if you have a higher risk of serious illness. Keep in mind some people may have COVID-19 and spread it to others, even if they don’t have symptoms or don’t know they have COVID-19.
Avoid crowds and indoor places that have poor ventilation.
Wash your hands often with soap and water for at least 20 seconds, or use an alcohol-based hand sanitizer that contains at least 60% alcohol.
Wear a face mask in indoor public spaces and outdoors where there is a high risk of COVID-19 transmission, such as at a crowded event or large gathering. Further mask guidance differs depending on whether you are fully vaccinated or unvaccinated. Surgical masks may be used if available. N95 respirators should be reserved for health care providers.
Cover your mouth and nose with your elbow or a tissue when you cough or sneeze. Throw away the used tissue. Wash your hands right away.
Avoid touching your eyes, nose and mouth.
Avoid sharing dishes, glasses, towels, bedding and other household items if you’re sick.
Clean and disinfect high-touch surfaces, such as doorknobs, light switches, electronics and counters, daily.
Stay home from work, school and public areas if you’re sick, unless you’re going to get medical care. Avoid public transportation, taxis and ride-sharing if you’re sick.
If you have a chronic medical condition and may have a higher risk of serious illness, check with your doctor about other ways to protect yourself.
Travel
If you’re planning to travel, first check the CDC and WHO websites for updates and advice. Be prepared to wear a mask and use appropriate hand hygiene when in public. You may also want to talk with your doctor if you have health conditions that make you more susceptible to respiratory infections and complications.