Coronavirus Project

Welcome to the Coronavirus Project. This new initiative of FAS aims to debunk misinformation circulating the web on matters of public health and safety, as well as provide clear and sourced information for policymakers. Below, we cut through the noise to present clear information and advice for the public, policymakers, and reporters looking for scientist-led and evidence-based analysis. We want to make science accessible, so we are translating scientific papers full of jargon and shoptalk into plain language for anyone who wants to be in the know.

Debunking viral misinformation

Since late 2019, information about the COVID-19 novel coronavirus has been trickling out from sources around the web. But not all information is created equal. Some of this information comes from science and medical professionals, who have years of experience. Some comes from unreliable anonymous internet accounts, bad actors, and hoaxers.

Below, we provide answers to some of the most pressing and complex questions from policymakers and the general public. These answers are crafted by experts and scientists. You can also find myths and misinformation that have spread, with the correct information.

Even more questions can be found on our new Ask A Scientist page, where you can easily search our database of questions, as well as ask our network of scientists your pressing questions.

Translating science for the public

When people infected with the COVID-19 virus breathe out, clear their throats, cough, sneeze, speak, or otherwise move air out through their nose or mouth, droplets of all different sizes, which can contain the virus, are ejected into the air. Many people infected with the COVID-19 virus – perhaps up to 25 percent – wouldn’t even know they are ejecting virus-laden droplets, as they may not exhibit symptoms.

Droplets suspended in the air are called an aerosol. Droplets that are large can remain in the air  for seconds to minutes before falling to the ground. Smaller droplets stay in the air longer – minutes to even hours. It is important to note, however, that unless you are physically near an infected person, COVID-19 virus in the air is unlikely to be a risk, because it is not likely to be present at a high enough level in the air to cause an infection to those who are far away. 

We should all be minimizing the amount of time we spend in any one place, especially if others are nearby. This limits the time a person is potentially exposed to the virus.

It is also very important to stay as far away from one another as possible, minimum 6 feet. The farther, the better. Some experts recommend staying at least 25 feet away from others, even when outdoors.

The traditional definition of airborne transmission is that small droplets containing a pathogen remaining viable over long time periods travel long distances in the air and infect other people when the pathogen is breathed in. Measles and tuberculosis are examples of respiratory diseases that remain infectious in the air for long time periods. The measles virus can live for up to two hours in the air where an infected person coughs or sneezes. Tuberculosis can live in the air for up to six hours.

Under experimental conditions, researchers found that the COVID-19 virus stayed viable in the air for three hours. The researchers estimate that in most real-world situations, the virus would remain suspended in the air for about 30 minutes, before settling onto surfaces. This is similar to what was found for SARS and MERS, which some researchers consider likely to be spread via airborne transmission. Furthermore, the Centers for Disease Control and Prevention recommend airborne precautions for the care of COVID-19 suspected or confirmed patients.

Many unknowns remain about the COVID-19 virus, such as how many virus particles need to be breathed in for an infection to begin. However, it is likely that active COVID-19 virus travels through the air when ejected by infected people. By staying as far away from one another as possible, keeping on the move, avoiding touching our faces, frequently washing our hands well with soap and water, coughing or sneezing into the crook of our elbows, wearing masks, and staying home when sick, we can protect ourselves and others.

Unsubstantiated theories about the COVID-19 novel coronavirus being created in a lab were fanned when a study (posted online and later retracted) implied that four parts of HIV, the virus that causes AIDS, could have been engineered into the COVID-19 virus. 

On Friday, February 14th, a group of researchers published a paper that adds to the scientific evidence debunking the conspiracy theory. 

The researchers confirmed earlier scientific reports that the COVID-19 virus is most closely related (96% identical) to a coronavirus that was previously identified in bats. It further provided evidence for why parts of HIV-1 were not incorporated into the COVID-19 virus.

The researchers show that the COVID-19 virus most likely evolved from bat coronaviruses, and that it has not been engineered with 4 parts of HIV-1. 

First, three out of the four COVID-19 virus parts in question are found in three other coronaviruses that had been previously isolated from bats, suggesting an evolutionary linkage. 

Second, when these four DNA parts are compared to the DNA of other species, researchers found that these DNA parts are also found in the DNA of mammals, insects, bacteria, and other coronaviruses. That means these DNA elements are found throughout the evolutionary tree and are not unique to HIV-1. 

Currently scientists are working around the clock to determine which animal was the original host of COVID-19 and which mutations the virus obtained that enabled it to infect humans.

Read NIH director Dr. Francis Collins’ synopsis of a recent article that provides strong scientific evidence that this novel coronavirus arose naturally.

A paper published by the Chinese Center for Disease Control (China CDC) analyzes the characteristics of all the COVID-19 cases reported to China’s Infectious Disease Information System. This included over 72,000 patient records with 44,672 confirmed cases. Almost 81% of the cases had mild symptoms. About 8,500 cases out of the over 44,600 that were confirmed had severe or life-threatening symptoms. This paper was written to explain how the virus behaves and help develop effective control strategies to prevent others from getting sick.

According to the data, most of those infected (77.8%) with COVID-19 were between 30 and 69 years old. In China’s population overall, about 57% of the population is within this age bracket. The virus had a fatality rate of about 2.3% and most fatalities occurred when the patients had other severe health issues, such as diabetes, hypertension, or cardiovascular disease. The highest rates of fatalities occurred in patients 60 years and older. This rate is lower than the other notable coronavirus epidemics, Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS), which had fatality rates of about 11% and 34.4%, respectively. However, COVID-19 is estimated to be more contagious. The number of people a sick person could infect, otherwise known as R0, is how scientists determine how contagious a disease can be. The R0 for SARS and MERS are three and less than one, respectively, and COVID-19’s estimated R0 is about 3.28.

The researchers stated that the data was consistent with the current theory of how COVID-19 originally spread from animals at a Wuhan seafood market. Additionally, they noted that its high rate of mutation allowed it to become infectious to humans and get increasingly efficient at being spread to others. Nevertheless, the authors suggested that the rates of infection are currently slowing. The data show that the number of confirmed cases likely peaked around February 1 and the rate of cases since then has declined. This decline, the researchers explained, could be attributed to the extensive information campaigns from national and international health organizations and the restriction of individuals’ movement between affected cities.

Unsubstantiated claims about the source of the COVID-19 novel coronavirus – that it is a bioweapon, or that it was made in a lab – are contradicted by research produced by the science community pointing to transmission of the COVID-19 virus from animals to people.

Researchers have found that three quarters of new or emerging diseases that infect people are transmitted to us from animals. For example, the Middle East Respiratory Syndrome (MERS) virus was probably transmitted to people from camels in the Arabian Peninsula, and the Severe acute respiratory syndrome (SARS) virus may have come from bats, or a different animal reservoir, before spreading to civet cats, and then to people in southern China. Viruses are capable of spilling over from animals to people largely because their genetic information mutates, or changes, quite readily.

Scientific evidence suggests the COVID-19 virus also spilled over from animals to people. One paper showed that the COVID-19 virus is 96% genetically identical to a coronavirus that was previously identified in bats, and researchers are working to discover even closer coronavirus matches in animals to home in on the path of spillover into people. Two preliminary studies indicate that the COVID-19 virus could have passed through pangolins (“scaly anteaters”). As more research is conducted, the transmission chain of the COVID-19 virus will become clearer.

During this concerning outbreak of COVID-19 virus, it is tempting to speculate about the source of the outbreak, or give credence to sensational claims. However, to participate in an effective response to the outbreak, it is best to rely on research findings based on science.

While pharmaceutical companies and government agencies have focused efforts on sequencing the genome of COVID-19 and creating vaccines as a response to the outbreak, existing antiviral agents, specifically those developed to treat HIV, hepatitis/C and influenza, have also demonstrated potential to treat COVID-19. Similar therapeutic approaches were effective in treatment of SARS and MERS, other human coronaviruses. 

Vaccine development and public uptake is estimated to take months to years, and repurposing existing antiviral agents could more urgently contain the outbreak. 

Initial analysis of COVID-19 genomic sequencing demonstrate similarities between the four nonstructural proteins and the spike protein that are served as targets for SARS and MERS treatment. 

A type of antiviral called nucleoside analogues (favipiravir and ribavirin, which are approved, and remdesivir and galidesivir, which are experimental) can block RNA synthesis in coronaviruses, and are being studied in Randomized Control Trials for COVID-19 treatment. Reports have demonstrated the ability of another type of drug called protease inhibitors (disulfiram, lopinavir and ritonavir) to block SARS and MERS, though clinical trials have not yet proven effectiveness. Griffithsin, another type of therapeutic, can also target spike glycoproteins, and should be evaluated for effectiveness in COVID-19. 

Finally, another class of drugs called pegylated interferons, used in hepatitis B/C treatment, in combination with a nucleoside compound could attack COVID-2019, but would require evaluation for safety. Other small molecules approved for treatment of non-coronavirus diseases could also be assessed and evaluated for effectiveness. 

Upcoming needs for COVID-2019 response include screening of existing MERS and SARS inhibitors and optimization of their activities against COVID-2019.

Original article: Therapeutic options for the 2019 novel coronavirus (2019-nCoV)

The CDC COVID-19 virus test kit, named the CDC 2019-nCoV Real-Time RT-PCR Diagnostic Panel, initially sent to public health laboratories is based on the principles of molecular biology. Since the COVID-19 virus’ genetic material is made up of ribonucleic acid (RNA), the virus can be detected using a method relying on short deoxyribonucleic acid (DNA) strands designed to attach to the virus’ RNA.

The CDC test kit consists of two mixes (N1 and N2) of short DNA strands that specifically detect the COVID-19 virus, a mix (N3) of short DNA strands that detect severe acute respiratory syndrome (SARS)-like coronaviruses, a mix (RP) of short DNA strands that detect the human gene RNase P, and a sample (nCoVPC) that contains noninfectious lab-synthesized COVID-19 virus N gene RNA as well as human RNase P DNA. Mixes N1, N2, and N3 should all be able to detect the COVID-19 virus. Mix RP should be able to detect the human gene RNase P and be used to evaluate the quality of specimens from patients. Sample nCoVPC should allow lab professionals to check if the test is working properly.

Because COVID-19 virus RNA would be present in relatively low amounts in samples from patients, like those collected by nasal swabs, the amount of nucleic acid that denotes viral presence needs to be boosted in order for it to be detected. This is done using a technique called real-time reverse transcriptase (RT)-polymerase chain reaction (PCR) that amplifies and monitors nucleic acid from initial COVID-19 virus RNA. Real-time RT-PCR reads out viral RNA into DNA, and then copies the DNA over and over again, generating a detectable signal if the specimen contained COVID-19 virus. Mixes N1, N2, and N3 consist of DNA primers that enable read out and copying, as well as DNA probes whose dyes enable the production of a fluorescent signal. In theory, a single copy of the COVID-19 virus RNA genome is detectable by real-time RT-PCR; in practice, coronaviruses need to replicate in order for there to be enough genetic material that can be used for the test.

The fluorescent signals that are produced over the course of the test are tracked and measured by sensitive instrumentation and a specialized software package. As long as controls – intended to be studied side-by-side with specimens potentially harboring COVID-19 virus RNA – perform as expected, showing that the test is working properly, a specimen is designated as positive if all three signals produced from its RNA being separately mixed with N1, N2, and N3 cross a carefully set threshold value.

A false story that a mandarin orange was infected by the COVID-19 novel coronavirus and was then eaten by a prisoner shortly before their death was shared widely in Malaysia, where misinformation about the COVID-19 outbreak has been particularly pervasive.

There are no coronaviruses known to infect mandarin oranges, and no coronaviruses known to infect any plant. Out of hundreds of known coronaviruses, most spread among animals, and seven, including the SARS (severe acute respiratory syndrome), MERS (Middle East respiratory syndrome), and COVID-19 viruses, are known to be able to make people sick. The SARS, MERS, and COVID-19 viruses all spilled over from animals to people. It is estimated that throughout Southeast Asia alone, additional thousands of yet-to-be-discovered coronaviruses are present in bats.

Plants and animals are both made up of building blocks called cells, and to infect a plant or animal, a virus must enter a cell and direct more copies of itself to be made; then, the virus copies must exit the cell. However, plant and animal cells are different, so viruses are typically adapted to either plants or animals. For instance, viruses that infect plants code for a ‘movement protein’ that is needed for the virus to spread throughout the plant, and the COVID-19 virus’ genome does not code for a movement protein. Since some viruses evolve along with plants and some evolve along with animals, a virus that evolves and becomes specialized to infect both plants and animals would be atypical.

That being said, preliminary findings suggest it’s possible for the COVID-19 virus to survive for a few hours or more on surfaces, so best practices for preparing food are advisable, especially in areas where there are COVID-19 outbreaks.

Researchers evaluated the SARS, MERS, and novel coronavirus (COVID-19) epidemics to determine what areas of preparedness need improvement. They studied the Centers for Disease Control and Prevention (CDC) website and PubMed database during each outbreak and found several interesting points. Specifically, the COVID-19 virus spread more quickly because of increased globalization, inadequate assessments of the virus’ urgency, and limited reporting of cases within China. The Chinese government waited almost two months from the first official case to implement travel restrictions, which allowed millions to travel through the virus hot zone unaware of the risk. Similar timing issues occurred during the 2002 outbreak of SARS and added to panic surrounding the disease. MERS did not spread as effectively between people but the biggest challenge was the difficulty of controlling the infections that were already ongoing. To mitigate the spread of the current coronavirus and to prepare for future outbreaks, the researchers suggest encouraging hand hygiene, isolating infected individuals in properly ventilated hospitals, and preventing contact with suspected animal hosts by reducing the number of live animal markets.

This paper examined the cases of nine infants in China who were infected with the novel coronavirus to better understand how it affected children. All of the infants’ families had at least one member who was also infected with the COVID-19 virus. None of the cases required intensive medical care and one had no symptoms of COVID-19 but had tested positive for the virus. Because the infants all had family members with the virus, the researchers recommended that families with babies and sick individuals should take steps to monitor their babies’ health and reduce virus transmission. This includes requiring adult caretakers to wear masks to prevent them from spreading the disease to the infants, wash their hands before coming into close contact with infants, and sterilize baby toys and tableware regularly.

A researcher studied the rate of COVID-19 infections on the Diamond Princess cruise ship to better understand how the novel coronavirus spread. One of the most difficult parts of predicting the spread of illness is determining the timing of initial infection. To study this, the author used a back-calculation method which started with the total number of cases on February 24 and worked backwards to figure out when the spread first began. From this calculation, the author found that the highest rate of infection was between February 2 and February 4, right before movement restrictions were instituted. However, after the passengers disembarked, some started experiencing symptoms of the virus, even when they did not have any close contact with infected individuals. Because of this, the author recommends studying other modes of virus transmission, such as from asymptomatic individuals and from the environment.

To find out how the novel coronavirus could spread, researchers took samples from the isolation rooms of three patients at a designated outbreak center in Singapore. Samples from two patients were taken after routine cleaning and the third sample was taken prior to cleaning. The samples taken after the cleanings did not contain virus particles. The third sample before cleaning the patient’s room had several positive results. Positive samples were found in the bathroom sink and toilet bowl, as well as on vents in the room. This suggests that it may be possible to transmit the virus through contact with stool. However, the researchers did not test to see if the virus particles they retrieved were capable of infecting another person. Nevertheless, the study emphasizes that strict environmental and hand hygiene is important to limit the spread of the novel coronavirus.

Scientist Q&A

What are the prospects for the development of medical countermeasures, such as a vaccine or antivirals, against the COVID-19 virus?

Many groups are working on devising medical countermeasures to COVID-19. A phase I trial of a vaccine candidate has been started in Seattle, but it could take more than a year for a safe and effective vaccine to be ready to be distributed to the public.
Efforts are also underway to develop antiviral treatments, like cocktails of antibodies, that could help patients infected by COVID-19 virus. The antiviral drug remdesivir is already being tested in patients in Wuhan and early clinical trials in the U.S. are underway.
For more info, please refer to the antivirals tab below.

What should I do to be prepared in case an outbreak occurs near me?

Just like people should prepare for hurricanes, people need to be prepared in case of a pandemic. DHS recommends that people have two weeks of food, water, and necessary prescription medicines; a supply of nonprescription medicines for pain, stomach issues, cold, flu, etc.; copies of electronic health records from doctors, hospitals, and/or pharmacies; and a plan for how to take care of loved ones if they get sick. These supplies will help people safely get through any decrease in normal public services or interruption in regular business. During any outbreak, individuals should also practice good hygiene to prevent the spread of illness through frequent hand washing, avoiding close contact with others, and refraining from touching one’s face.

Unlike the four strains of coronavirus behind about 20% of the cases of common cold, COVID-19 virus can cause severe illness, and even death. This is because while coronaviruses causing the common cold infect the nose and throat, which comprise the upper respiratory tract, COVID-19 virus infects the lungs, which is the lower respiratory tract. That can bring on pneumonia. The determining factor of where in the human body infection occurs is the structures on the outside of the virus that interact with the structures on the outside of cells that make up different human organs or tissues. Moreover, since coronaviruses that cause the common cold replicate in the upper respiratory tract, they are more likely to be spread than viruses that replicate only in the lower respiratory tract. Pathogens get in and out of the nose and throat more easily than the lungs, and the lungs’ defenses against viruses are more robust. The National Institutes of Health supports fundamental research into the mechanisms by which viruses infect people and replicate.

Identifying people who may be infected with COVID-19 virus relies on recognizing the symptoms that are caused by infection and determining how an individual may have been exposed to COVID-19 virus.

When infected with COVID-19 virus, some people may exhibit no or minor symptoms, while others may become very sick, or even die. Symptoms can include fever, cough, or shortness of breath. Fever is stimulated in response to viral infection because as part of the human immune response, increased body temperature is less favorable for viral replication, which is heat sensitive. Coughing is a reflex that is stimulated by an irritant, in the case of COVID-19 virus, viral particles attacking the lungs. COVID-19 can cause shortness of breath because it disrupts the lungs.

If an individual is experiencing fever or lower respiratory illness (characterized by cough or shortness of breath), it is important to learn whether the person had the opportunity to be exposed to COVID-19 virus. Exposure is possible if the person had been in any of the countries with ongoing transmission at any time during the 14 days before the symptoms started or came into close contact with a person known or suspected to be ill with COVID-19 in that time period. There is also community transmission in some areas in the US, so tests that rule out other diseases and that can detect the COVID-19 virus may be needed. Community transmission means that there is a person infected with the COVID-19 virus, but how the person became infected is unknown.

Public health experts believe the COVID-19 virus incubation period may range from 48 hours to 14 days after exposure. If a person is around 6 feet from an individual – a “close contact” – who can spread COVID-19, the person is at risk of contracting the virus. This is because coronaviruses can spread when infected people cough or sneeze, sending respiratory droplets containing the virus sailing into others’ mouths or noses, which can then even be inhaled into the lungs.

If an individual is experiencing COVID-19 symptoms, they should communicate with their doctor, and based on the clinical course of illness, the individual’s travel history, recent contacts with others who may be infected, or local COVID-19 epidemiology, the individual may be isolated and tested. The US Centers for Disease Control and Prevention (CDC), other public health labs, university hospital labs, and companies have developed tests for the analysis of patients’ specimens. The CDC test relies on a technique called real-time reverse transcriptase (RT)-polymerase chain reaction (PCR). To conduct this test, COVID-19 virus genetic material needs to be extracted from specimens, such as those collected by nasal swabs. A virus’ genetic material is usually made out of the nucleic acids ribonucleic acid (RNA) or deoxyribonucleic acid (DNA). Because viral genetic material – in the case of COVID-19 virus, viral RNA – would be present in relatively low amounts, the amount of nucleic acid that denotes viral presence needs to be boosted in order for it to be detected. The amplification and monitoring of nucleic acid from initial COVID-19 virus RNA is performed using real-time RT-PCR, which reads out viral RNA into DNA, and then copies the DNA over and over again, generating a detectable signal if the specimen contained COVID-19 virus. In theory, a single copy of the COVID-19 virus RNA genome is detectable by real-time RT-PCR; in practice, coronaviruses need to replicate in order for there to be enough genetic material that can be used for the test.

Dr. Anthony Fauci, Director of the National Institute of Allergy and Infectious Diseases (NIAID), noted that during his conversations with colleagues in China “they told me without a doubt there is some degree of asymptomatic transmission.” Furthermore, Dr. Robert Redfield, director of the Centers for Disease Control and Prevention (CDC), said “there’s been good communication with our colleagues to confirm asymptomatic infection, to confirm asymptomatic transmission, to be able to get a better handle on the clinical spectrum of illness in China.” This would indicate that the virus can indeed be spread prior to the onset of symptoms such as coughing, fever, and shortness of breath.

However, national and international health organizations working to mitigate the spread of the virus are still collecting data on asymptomatic transmission, and since people who cough or sneeze are more likely to spread it than people who exhibit no symptoms, groups like the World Health Organization (WHO) say that asymptomatic transmission plays minor roles in epidemics. The Centers for Disease Control and prevention website will update with definitive information about how COVID-19 virus spreads.

Vaccines are critical tools for preventing the spread of disease, and are challenging to develop. A vaccine stimulates a person’s own immune system to defend against infectious viruses the person may encounter.

There are a number of approaches for developing a vaccine. Whole pathogens can be weakened, or entirely inactivated, and used to inoculate people. Or a part of a pathogen can be tested for its ability to stimulate a person’s immune system and provide protection.

Vaccine production can be egg-based or cell-based. Egg-based production relies on large numbers of chicken eggs, requires working with active virus, and can take a long time. Cell-based production uses cells cultured in the lab, is compatible with recombinant technology (which allows a lab to start the vaccine production process with genetic information about the virus, rather than a physical sample of the active virus), and has the potential to be conducted more rapidly. 

After limited production and successful clinical trials, vaccine manufacturing is scaled up, and vaccines can be distributed to the general public.

Federal stakeholders: Centers for Disease Control and Prevention, National Institutes of Health, Department of Defense, Department of Homeland Security

Governments, pharmaceutical companies, and international health organizations are racing to determine ways to treat or prevent the spread of COVID-19. One of the ways that is being explored is the development of new, or the use of existing, antivirals. Viruses are packets of RNA or DNA inside a protein capsule that are absorbed by healthy cells and instruct them to make copies of the virus and release them. Antivirals work by interfering with important proteins in the viruses that allow them to enter cells, multiply, or escape from infected cells.

Scientists are currently testing different types of antivirals that work against influenza, HIV, and even Ebola, to see if they are effective against COVID-19 virus. In animal models, scientists have found that a drug that was developed by Gilead for Ebola called remdesivir, can prevent coronaviruses like Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS) from replicating and infecting healthy cells. Because SARS and MERS are similar to COVID-19, scientists are looking to apply these results to models of COVID-19.

Medical experts in China are already treating patients with remdesivir to try to reduce the severity of their symptoms. An individual in the U.S. who was treated with remdesivir saw improvement in his symptoms in one day. However, it is important to note that this treatment is highly experimental and scientists need more information to determine if it is widely effective against COVID-19 before administering it to the general population.

The National Institutes of Health sponsors fundamental research that underpins the development of antivirals.

Viruses are vulnerable outside our bodies because of how they are built. Specifically, they are pieces of RNA or DNA contained in a special coating of proteins called capsids. Viruses cannot replicate unless absorbed by cells in our body. Once a virus is outside the body, its capsid starts to degrade, and the more degraded its capsid is, the less likely it is to survive. When outside the body, these capsids degrade faster in cold, dry environments. They also degrade faster on soft, rather than on hard surfaces. That’s because they need moisture to survive and soft surfaces absorb that moisture. While it is difficult to determine exactly how long viruses can stay intact outside the body, since it is so dependent on environmental conditions, different viruses do appear to have different levels of resiliency. Flu viruses, for example, are generally rendered harmless after nine hours on hard surfaces and four hours on soft surfaces. The Middle East Respiratory Syndrome (MERS), which is in the same virus family as COVID-19 virus, and lasts for two days on hard surfaces, and a recent study concluded that human coronaviruses can last on surfaces at room temperature for up to 9 days.

The World Health Organization’s early estimates suggest that COVID-19 virus “may persist on surfaces for a few hours or up to several days.” Surfaces can be cleaned with household disinfectants, and be sure to wash your hands.

The Centers for Disease Control and Prevention website will update with definitive information about the survivability of COVID-19 outside the human body.

Research modeling the early stages of the COVID-19 outbreak consistently suggested that the number of people infected by COVID-19 was likely considerably higher than the reported numbers of confirmed cases.

For example, work led by a researcher at Northeastern University estimated that as of Wednesday, January 29th, 31,200 people in Wuhan alone could have been infected, compared to the reported 2,261 confirmed cases.

Discrepancies between estimated and reported COVID-19 cases could be due to infected people with no or minor symptoms not seeking medical attention, backups of specimen testing, or other healthcare system shortages.

The US Centers for Disease Control and Prevention is tracking the outbreak and coordinating with state and local public health officials to minimize the spread of the COVID-19 virus.

Experts: Steven HoffmanDaniel Lucey

At the beginning of the COVID-19 outbreak, samples could only be tested at the Centers for Disease Control (CDC) headquarters in Atlanta, Georgia. However, as the outbreak grew, local health officials needed to be able to quickly confirm whether a patient contracted the disease, instead of waiting for CDC to perform the analysis themselves. CDC then asked the Food and Drug Administration (FDA) for an emergency approval of the necessary tests so local officials could rule out cases on their own.

The FDA had to approve the use of these tests because it is in charge of how medical countermeasures and diagnostics are used in the U.S. population. In public health emergencies, such as the COVID-19 outbreak, sometimes tests and treatments for similar diseases can be adapted for use during the emergency. To use these tests and treatments in an “off-label” way, the FDA has to issue a temporary Emergency Use Authorization (EUA). EUA have been used to help treat people during a number of recent public health emergencies, like the Ebola, Zika, and Middle East Respiratory Syndrome (MERS) outbreaks.

Now, some public health labs, university hospital labs, and medical testing companies have developed tests, and testing is being carried out throughout the US, although capacity is limited in some areas.

The US Centers for Disease Control and Prevention (CDC) has developed a test for the analysis of patients’ specimens. The test relies on a technique called real-time reverse transcriptase (RT)-polymerase chain reaction (PCR). To conduct this test, COVID-19 virus genetic material needs to be extracted from specimens, such as those collected by nasal swabs. A virus’ genetic material is usually made out of the nucleic acids ribonucleic acid (RNA) or deoxyribonucleic acid (DNA). Because viral genetic material – in the case of COVID-19 virus, viral RNA – would be present in relatively low amounts, the amount of nucleic acid that denotes viral presence needs to be boosted in order for it to be detected. The amplification and monitoring of nucleic acid from initial COVID-19 virus RNA is performed using real-time RT-PCR, which reads out viral RNA into DNA, and then copies the DNA over and over again, generating a detectable signal if the specimen contained COVID-19 virus. In theory, a single copy of the COVID-19 virus RNA genome is detectable by real-time RT-PCR; in practice, coronaviruses need to replicate in order for there to be enough genetic material that can be used for the test. More field testing of this assay with real patient samples is necessary to determine its true accuracy.

After the CDC submitted a request for emergency authorization to the Food and Drug Administration, FDA issued an expedited approval of the assay, and it can now be used by state health labs as well as CDC. Other organizations are working on the development of different COVID-19 diagnostics that could potentially be more rapid or more sensitive.

This is an evolving situation, but here is what is known so far. 

When infected with COVID-19, some people may exhibit no or minor symptoms, while others may become very sick, or even die. Symptoms can include fever, cough, or shortness of breath. Fever is stimulated in response to viral infection because as part of the human immune response, increased body temperature is less favorable for viral replication, which is heat sensitive. Coughing is a reflex that is stimulated by an irritant, in the case of coronavirus, viral particles attacking the lungs. The coronavirus can cause shortness of breath because it disrupts the lungs, which help transport oxygen to the body, and remove carbon dioxide. Less severe human coronaviruses can cause mild to moderate upper respiratory illness with symptoms like runny nose, headache, cough, sore throat, fever, or a general feeling of being unwell.

According to Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, “a quarter of China’s [COVID-19] cases require intensive treatment.”

The fatality ratio for known cases of COVID-19 is about 0.6% in South Korea and 0.7% in China outside of Wuhan, which is more deadly than flu.

More detailed information about what is being observed in the clinic can be found on the Centers for Disease Control website.

The Occupational Safety and Health Administration (OSHA) recommends that healthcare workers use a combination of standard procedures to protect themselves, including wearing gowns, gloves, National Institute for Occupational Safety and Health (NIOSH)-certified disposable N95 or better respirators, and eye/face protection. According to the Food and Drug Administration (FDA), “the ‘N95’ designation means that when subjected to careful testing, the respirator blocks at least 95 percent of very small [300 nanometer] test particles.” The diameter of COVID-19 virus particles is reported to be about 60 to 140 nanometers. However, this mask is not suitable for children, people with facial hair, and those with respiratory conditions such as asthma.

The face masks that are most often used by the public are generally considered ineffective against the spread of disease because they often do not create a tight seal against the face and offer little protection when moist. The cloth reusable face masks offer even less protection because often people do not clean them properly and can actually transmit diseases to the wearer through the moisture trapped on the inside and outside of them. Doctors recommend that only sick individuals use face masks to temporarily prevent the spread of disease to others.

The World Health Organization (WHO) has decided to name the disease caused by the novel coronavirus “COVID-19” and refers to the virus that causes it as the “COVID-19 virus.” CO for corona, VI for virus, D for disease, and 19 for the year the outbreak was first recognized, late in 2019. Separately, the Coronavirus Study Group of the International Committee on Taxonomy of Viruses has named the new virus severe acute respiratory syndrome-related coronavirus 2, or SARS-CoV-2; however, this name has generated controversy in the public health and infectious disease community.

Before being officially named, the virus was commonly referred to as 2019 novel coronavirus, shortened to 2019-nCoV, or, in some cases, called Wuhan coronavirus, although the stigmatizing nature of that nomenclature is not preferable.

The director of the Office of Global Affairs at the Department of Health and Human Services, Mr. Garrett Grigsby, represents the US at the WHO.

Public health experts inside and outside the CDC have found that alcohol-based hand sanitizers (with at least 60% alcohol) are effective at killing the novel coronavirus if used properly. However, the problem is that many people do not either use enough hand sanitizer or accidentally wipe it off before it is dry for it to be as effective as possible.

The best technique is to apply the amount of hand sanitizer specified on the packaged (which is usually about a dime-sized amount), and then carefully and thoroughly rub it over the palms and the back of the hands and let it dry completely. Hand sanitizer is a good way to reduce the possibility of transmission if soap and water is not available (and if kids have a hard time washing their hands properly), but hand-washing for at least 20 seconds is overall the most effective way to get rid of viruses.

It is important to note that hand sanitizers are effective because they disrupt the membranes of a lot of different bacteria and viruses, including the novel coronavirus. However, they are not effective against viruses that do not have these membranes, like the norovirus, which causes the stomach flu. This is why encouraging and maintaining proper hand washing habits are more encouraged than relying on just hand sanitizer.

FAS Coronavirus Team

Ali Nouri
Project Director
@AliNouriPHD

Mike Fisher
Senior Fellow
@mykfish

Neekta Hamidi
Fellow

Lindsay Milliken
Research Assistant

Kathryn Kohn
Comms Manager

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