COVID-19 (Coronavirus, 2019-nCoV)

Medically Reviewed on 3/25/2022

Facts you should know about COVID-19 (2019 novel coronavirus, 2019-nCoV, Wuhan coronavirus)

Infection with the Wuhan coronavirus causes respiratory problems.
Infection with COVID-19 causes respiratory problems.
As the pandemic continues and more contagious COVID-19 variants emerge, the Centers for Disease Control and Prevention (CDC) encourages people to get two doses of the COVID-19 vaccine and a booster if available for their age group. Many people who are pregnant or trying to conceive wonder how COVID-19 vaccination may affect their fertility or the health of their unborn child. According to the CDC, "There is currently no evidence that any vaccines, including COVID-19 vaccines, cause fertility problems (problems trying to get pregnant) in women or men." The CDC also provided the following assurance: "Scientists have not found an increased risk for miscarriage among people who received an mRNA COVID-19 vaccine just before and during early pregnancy (before 20 weeks of pregnancy)."
  • COVID-19 is a disease caused by a type of single-stranded, positive-sense RNA coronavirus called SARS-CoV-2 that likely jumped from infecting only animal species to infecting humans that, in turn, developed person-to-person transmission that results in respiratory and other problems. The 2019 novel coronavirus is related to SARS and MERS coronaviruses.
  • This is a new disease, and as more data is gathered and with ongoing research, some of the information will change as more information becomes available.
  • Risk factors for infection with the 2019 novel coronavirus include the following:
    • Recent travel to places where there is an outbreak
    • Not being vaccinated
    • Close contact with people who are diagnosed with the disease
    • Close contact with anyone who has visited an outbreak zone
    • Contact with secretions or feces from an infected person
    • Eating or handling wild animals native to China (and other countries)
    • Touching surfaces exposed to the virus (door handles/counters)
    • Not wearing masks when in public places
    • Attending large gatherings
    • Attending gatherings indoors and not wearing a mask
    • Failure to maintain social distancing (at least 6 ft apart)
    • Not doing frequent hand washing/hand sanitizing
    • People in nursing homes
    • Obesity (BMI over 40)
    • Asthma
    • Type 1 and type 2 diabetes
    • Gestational diabetes
    • Older people (over 60-65 years old)
    • Chronic lung disease (for example, COPD, bronchitis, emphysema, idiopathic pulmonary fibrosis, cystic fibrosis, pulmonary hypertension)
    • Serious heart conditions (for example, heart failure, coronary artery disease, cardiomyopathies, congenital heart disease)
    • Chronic kidney disease (for example, patients with decreased renal function, patients on dialysis)
    • Chronic liver disease (for example, cirrhosis)
    • Immunocompromised patients (for example, patients with cancer treatment, bone marrow or organ transplant, immune deficiencies, HIV with a low CD4 cell count
    • Men have a higher incidence of infections than women
  • Signs and symptoms of COVID-19 infection from the CDC currently include the following:
  • Sometimes people infected with COVID-19 may also experience a runny or stuffy nose, aches and pains, tiredness, upset stomach, belly pain, vomiting, diarrhea, and a sore throat. There have been many reported cases where patients infected with the virus have no symptoms.
  • The virus likely initially spread in an animal species (currently unidentified) and then jumped to humans where it is transferred from person to person.
  • Treatment strategies are evolving. Treatment is supportive in nature, and it may be necessary for a medical professional to administer treatments in a hospital.
  • Complications may include
    • high fever,
    • severe cough,
    • difficulty breathing,
    • pneumonia,
    • respiratory failure,
    • organ failure, and
    • death.
  • People may prevent or lower the risk of this viral infection by good hygiene, wearing a mask when they leave home for any reason, being vaccinated, avoiding contact with infected people, social distancing, not going into an outbreak area, and leaving an outbreak zone.
  • Breakthrough cases of COVID variants can occur infrequently. In general, U.S.-approved vaccines work well in preventing severe infections that need hospitalization and/or life support.

What is COVID-19 (2019 novel coronavirus, 2019-nCoV, Wuhan coronavirus)?

SARS-CoV-2 is a single-stranded, positive-sense RNA coronavirus that causes an illness called COVID-19 (note that many people still equate and interchange the disease name COVID-19 with the new official virus named SARS-CoV-2). It is a new strain of coronavirus (means crown) that first caused an outbreak of serious respiratory problems in Wuhan, China. Researchers think it originated from infected animals and jumped over to infecting people in a large open seafood/animal market. Also, the virus is capable of person-to-person transmission, spreading to at least to over 150 countries in about 3 months. It is related to the SARS and MERS coronaviruses. The World Health Organization (WHO) declared COVID-19 a pandemic in March 2020.

Unfortunately, variants (type mutations of SARS-CoV-2) have developed during this ongoing pandemic. The WHO has designated variants Delta, Eta, Iota, Kappa, Lambda, Omicron, and Omicron subvariant BA.2 as "variants of interest" and is tracking other variants in several different countries.


What is COVID-19 (2019 novel coronavirus)? See Answer

What are the signs and symptoms of infection with COVID-19 (Wuhan coronavirus)?

COVID-19 symptoms may begin like the flu but go on to develop

  • fever,
  • severe cough, and
  • shortness of breath (difficulty breathing) that is so serious enough to warrant hospitalization in many patients.

 Occasionally, infected individuals may also experience

COVID toes is a syndrome where young adults and children develop a reddish-purplish discoloration of the toes and may indicate COVID-19 infection even before any other symptoms develop. In addition, doctors have noted an increase of COVID-19 patients with strokes. Mount Sinai Health in New York report a seven-fold increase in young patients (all under 50) with strokes. Doctors found that patients' blood clotted abnormally fast and found many clots in the bodies in about 20%-25% of patients. Although early in this outbreak, Chinese researchers' suggestion that people who are infected but don't show symptoms (incubation period) may be contagious actually proved to be correct. Researchers estimate that about 50% of transferred infections are due to asymptomatic infected people. This allows the virus to spread more effectively from person to person and makes it more difficult to isolate infected patients.

As more experience with COVID-19 occurs, other additional signs and symptoms may emerge (for example, stroke symptoms and multisystem inflammatory syndrome in children).

What are risk factors for any type of variant COVID-19 (Wuhan coronavirus) infections?

Initial risk factors for the virus included close contact with someone who has recently visited China, Italy, England, Spain, and many other countries and cities experiencing this outbreak. Close contact with anyone diagnosed with the virus and coming in contact with secretions (for example, those produced by sneeze or cough) or feces from an infected person are risk factors. Some investigators suggested that no wild animals be used for food in China or elsewhere. Since those initial risk factors were presented, many others have been noted and are as follows:

  • Asthma
  • Chronic kidney disease (for example, patients with decreased renal function, patients on dialysis)
  • Not wearing masks when in public
  • Attending gatherings indoors when not wearing a mask
  • Failing to maintain social distancing (at least 6 ft apart)
  • Not performing frequent hand washing/hand sanitizing
  • Chronic liver disease (for example, cirrhosis)
  • Chronic lung disease (for example, COPD, bronchitis, emphysema, idiopathic pulmonary fibrosis, cystic fibrosis, pulmonary hypertension)
  • Gestational diabetes
  • Immunocompromised patients (for example, patients with cancer treatment, bone marrow or organ transplant, immune deficiencies, HIV with a low CD4 cell count)
  • Men have a higher incidence of infections than women
  • Obesity (BMI over 40)
  • Older people (over 60-65 years of age)
  • People in nursing homes
  • Serious heart conditions (for example, heart failure, coronary artery disease, cardiomyopathies, congenital heart disease)
  • Type 1 and type 2 diabetes

How does COVID-19 (SARS-CoV-2) spread?

Many coronavirus types infect species of animals that occasionally (or rarely) are able to infect humans. MERS coronavirus is an example where the virus that usually only infected camels became able to infect humans. SARS-CoV-2 is similar as the initially infected people frequented an open-air food market that sold fish and animals, including wild animals. Medical researchers currently do not know the animal species infected, but wild animals are a suspected source. However, the rapid spread of the virus was due to person-to-person contact that has been responsible for the wide outbreak of this infection. Close contact with someone who is infected or with their secretions (for example, cough-generated aerosol droplets) or feces is how the virus spreads.

Unfortunately, at least two highly infectious COVID-19 mutation(s) of SARS-CoV-2 have been detected in several countries worldwide. The new strains appear to spread more easily, and one, Delta, is likely more virulent. Vaccines are effective against these mutant strains but less so than against the original type.

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What is the incubation period for COVID-19?

Medical researchers estimate that the incubation period for a COVID-19 infection varies from 2 days to about 14 days (average about 5 days).

Is COVID-19 contagious? How long are you contagious with COVID-19?

Although this virus is contagious, the contagious period remains to be determined. Recent findings showed that it is contagious even in the incubation period when the patient shows no symptoms. The virus also survives on surfaces for different time periods adding to the incident of transmission.

How do medical professionals diagnose COVID-19 infections? Are accurate COVID-19 tests available?

In the early phases of the pandemic in the U.S., only the CDC had tests to determine if an individual is infected with the virus, so doctors must safely package blood, swabs, and other specimens and send them to the CDC. It took days to get a result. However, early tests had some accuracy problems that researchers have since resolved. In addition, the FDA has approved about 20 different suppliers of various tests of blood and/or swab samples to quickly diagnose (from about 5-15 minutes) infected or uninfected people. In general, most tests rely on detection of pieces of the viral genes (nasal swab test) or detection of virus surface structure antigens by immunoglobulins (serology blood test). Testing is now available at many sites, hospitals, and doctors' offices around the country, but availability of these tests varies in many parts of the U.S. In addition, the FDA (Pixel Covid-19 test) approved a LabCorp COVID-19 at-home testing kit for emergency use.

What are treatment options for COVID-19 infections?

Fortunately, to date (January 2021), there is now an antiviral drug and vaccines to treat this infection. Symptom relief and supportive care (many requiring hospital care and some need ventilator respiratory support) are also part of the current treatment methods. However, early supportive care may reduce the disease severity. Supportive care may include treatments to reduce symptoms such as fever, cough, and nausea and oxygen by nasal cannula and even mechanical breathing support in severe infections. Other treatments that may be used and determined by your doctors (and availability) may include the following:

  • Monoclonal antibodies against SARS-CoV-2
  • Remdesivir
  • Dexamethasone

When to seek urgent medical care for a COVID-19 infection

If you have been exposed to the virus, put on a mask if one is available and call your doctor for detailed instructions. About 80% of infected individuals do not require hospital treatment. However, you should seek immediate medical care (go to the hospital/ER) if you develop one or more of the following (CDC criteria):

  • Trouble breathing
  • Persistent pain or pressure in the chest
  • New confusion
  • Inability to wake or stay awake
  • Bluish lips or face (cyanosis)

What are the complications associated with COVID-19 (SARS-CoV-2) infections?

Complications associated with this viral infection include

  • difficulty breathing (may require a breathing machine),
  • high fever,
  • pneumonia,
  • severe cough,
  • organ failure (for example, kidney failure), and
  • death.

How can people prevent a COVID-19 (SARS-CoV-2) infection? Is there a COVID-19 vaccine?

Specific recent recommendations are to get vaccinated as soon as possible and to wear a mask especially if you may encounter a crowd.

The following are the general directions given by the CDC for coronavirus prevention:

  1. Wash your hands often with soap and water for at least 20 seconds. If soap and water are not available, use an alcohol-based hand sanitizer.
  2. Avoid touching your eyes, nose, and mouth with unwashed hands.
  3. Avoid close contact with people who are sick.
  4. Stay home when you are sick.
  5. Cover your cough or sneeze with a tissue, and then throw the tissue in the trash.
  6. Clean and disinfect frequently touched objects and surfaces.
  7. Follow social distancing protocols.

In addition, because of the need for hospitalization for many infected people, many governments have taken steps to limit the chances to spread infections by isolation techniques such as closing down public events (and even preventing public transportation) and closing schools and workplaces. The U.S. and other countries have chartered planes to remove their citizens from outbreak areas in the world. In the U.S., airports are screening people arriving from high-risk areas. Many states issued orders for social distancing (keep 6 feet away from other people), meaning that all people should remain in their homes (except for essential workers) except for emergencies and getting food supplies until the infection level reaches a low percentage.

Vaccines to prevent a COVID-19 (SARS-CoV-2) infection are now available for anyone over 5 years of age. The two first cleared for emergency use in the U.S. by the FDA were the Pfizer/BioNTech vaccine and the Moderna vaccine. Also, the Johnson & Johnson vaccine was also cleared shortly after the initial two. Other vaccines are also being produced and administered in other countries (England, China, Russia). In addition, it is likely that several other vaccines against this disease may be FDA approved in the near future. The CDC has approved COVID-19 booster shots for certain age groups in order to provide protection against emerging variants.

What is the mortality rate for COVID-19 (SARS-CoV-2) infections?

This outbreak is about a year old. Determination of the mortality rate may change as the disease outbreak continues. For example, if hospitals become unable to give supportive care to patients because of a lack of hospital beds due to overcrowding, the mortality rate will likely increase. However, if the outbreak is contained quickly and the hospitals have enough beds available to treat patients, the mortality rate may decrease. However, as of Mar. 24, 2022, there were about 477,367,470 infected people worldwide with 6,109,725 deaths, which gives COVID-19 a current world mortality rate of about 1.28%. These rates will change, perhaps drastically, once mask-wearing and strict hand-washing protocols, along with worldwide vaccinations occur, experts suggest this pandemic can be controlled.

What are breakthrough COVID cases?

Breakthrough COVID cases are defined as those COVID infections that occur 2 or more weeks after completion of any vaccine regimen. The infections can range from no symptoms to severe symptoms and/or death. However, they are relatively rare (rate data suggests 0.01% between January and April). Breakthrough infections occur in patients who have a weak and/or short time immune response to the vaccine. In addition, variants can have an altered structure that allows only a partial or reduced susceptibility to vaccine-generated immune responses. For example, the original vaccines were about 90%-95% effective against the original virus, but the now-predominant Omicron variant (about 59% of all U.S. cases in the winter of 2021) is less susceptible to the current vaccines but very susceptible to stopping the need for hospitalization and/or death. As of January 2022, booster doses of the vaccine are recommended for immunocompromised individuals.

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Medically Reviewed on 3/25/2022
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