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8 facts about the coronavirus to combat common misinformation

Moderna, Pfizer and AstraZeneca have released promising results from their initial coronavirus vaccine trials. Here are answers to common questions about them. (Video: The Washington Post)

Living through a pandemic in the Internet age means misinformation can sometimes spread more rapidly than facts.

Faced with a deluge of claims about the coronavirus and the illness it causes, covid-19, you may be wondering whether gargling with saltwater is a cure or if the pathogen was man-made in a Chinese laboratory. (Spoiler: Saltwater doesn’t work, and scientists believe the virus occurs in nature.)

To help you out, we rounded up eight facts about the coronavirus to keep in mind if you see claims to the contrary.

Fact: Masks help prevent the spread of the coronavirus

Several studies support the theory that face coverings reduce the risk of infection. Robert Redfield, director of the Centers for Disease Control and Prevention, testified before the Senate in September that masks are “the most important, powerful public health tool we have” for combating the pandemic.

Part of the confusion about face coverings seems to have come from President Trump’s false claim in October that 85 percent of people diagnosed with covid-19 wore masks — a mischaracterization of a CDC study.

As The Washington Post’s Fact Checker explained, that study compared groups of people who had tested positive and negative for the coronavirus and found that a much higher percentage of the positive cases had had close contact with someone known to have covid-19. The people in the positive group were also more likely to recently have eaten at a restaurant.

In the 14 days before they got sick, the study says, 71 percent of positive cases and 74 percent of the negatives reported “always” wearing a mask in public. Those numbers are almost the same, with the main difference between the groups being that a higher percentage of the positive cases had contact with an infected person.

Masks, of course, work only when you’re wearing them. It matters what you do when you take them off. Someone can say they “almost always” wore a mask and still could have had instances when they needed to take it off in a public setting — say, while dining out.

Fact: There are no known cures for covid-19

While a cure for covid-19 would be more than welcome, no drug or other treatment has been found to eliminate the illness. Since the coronavirus emerged in China late last year, myriad false rumors have circulated about potential cures, ranging from drinking bleach to snorting cocaine. The Food and Drug Administration has issued nearly 150 warning letters to companies fraudulently promising a cure, treatment, prevention method or diagnostic tool.

In reality, “the pharmaceutical toolbox for physicians to treat covid-19 is seriously restricted,” as The Post’s Christopher Rowland put it in September. The FDA so far has authorized only two drugs for the illness: remdesivir, for in-hospital use, and bamlanivimab, for people with mild or moderate symptoms.

Remdesivir appears only somewhat beneficial, with evidence that it shortens hospital stays but not that it improves a patient’s chance of survival. Health experts have expressed optimism about the effectiveness of bamlanivimab, but the drug is scarce and logistically complicated to administer.

Fact: Hospitals have no reason to purposely diagnose covid-19 inaccurately

The falsehood that hospitals are financially incentivized to over-diagnose people seems to stem from an interview that Minnesota state Sen. Scott Jensen (R) did with Fox News in April, in which he appeared to suggest that hospitals would inflate their coronavirus numbers if they were being reimbursed more for those patients.

The Cares Act did include a provision to reimburse hospitals more for uninsured coronavirus patients and those with Medicare, but there is no evidence that hospitals are gaming the system. Jensen eventually walked back his claim in an interview with, in which he said he did not believe that hospitals were intentionally misclassifying cases for financial benefits.

In part because Congress knew that Medicare reimbursement rates are far lower than those of private insurers, the Cares Act provided an additional 20 percent reimbursement for hospitals on top of Medicare’s normal rate for a coronavirus patient. The law also created a $100 billion fund to reimburse hospitals for uninsured patients at Medicare rates.

Still, an analysis by the Kaiser Family Foundation found that the fund may not be enough to cover the costs of the uninsured, as well as the purchase of medical supplies and construction of temporary medical facilities. In reality, hospitals are probably losing money on covid-19 patients because the illness is difficult to treat and many hospitals have been overwhelmed by a surge of people needing care.

Fact: The coronavirus is more deadly than influenza

Unfortunately, the coronavirus is much more lethal than seasonal flu. About 2 percent of diagnosed coronavirus cases are lethal, compared with 0.1 percent of diagnosed flu cases.

For both illnesses, experts believe that far more people are infected than receive official diagnoses — meaning the true death rates are probably much lower. The CDC estimates that, including people who have been infected with the coronavirus but didn’t know it, the U.S. death rate is around 0.65 percent. The flu’s infection fatality rate may be about 0.05 or 0.025 percent, epidemiologists estimate.

There’s also no truth to the idea that doctors are inflating the coronavirus death toll by indiscriminately attributing deaths to covid-19. To determine a cause of death, physicians consider the patient’s infection, response to treatment and medical history. They also look at whether underlying conditions, which exist in most people who die of covid-19, contributed to the death.

Covid-19 is usually listed as a contributing cause of death, with the primary cause being a problem precipitated by the illness, like pneumonia. The official coronavirus death toll includes those fatalities because covid-19 spurred the other health issues that killed the patient.

Fact: The coronavirus vaccine candidates do not affect people’s DNA

Two vaccine candidates on the table for FDA approval — one from pharmaceutical giant Pfizer and German biotechnology company BioNTech, and another from biotechnology company Moderna — are examples of a new technology that uses a piece of genetic material called messenger RNA. That mRNA teaches the body’s cells to build the protein on the surface of the coronavirus, therefore making the immune system recognize and block the true virus.

This groundbreaking technology stands in contrast to traditional vaccines, which introduce into the immune system an inactivated or weakened version of a virus. But despite allegations suggesting otherwise, the coronavirus vaccine candidates using mRNA do not “affect or interact with” a person’s DNA, according to the CDC. Additionally, reputable news and fact-checking sources, including the Associated Press, the BBC, PolitiFact and Poynter, have confirmed with various scientists that mRNA vaccines do not change DNA.

“That’s just a myth, one often spread intentionally by anti-vaccination activists to deliberately generate confusion and mistrust,” Mark Lynas, a visiting fellow at Cornell University’s Alliance for Science group, told Reuters. “Genetic modification would involve the deliberate insertion of foreign DNA into the nucleus of a human cell, and vaccines simply don’t do that.”

Fact: Staying home, using hand sanitizer and washing our hands more often are healthy

None of those behaviors, which are recommended for preventing the spread of the coronavirus, pose a risk to our immune systems, despite claims that they do.

The incorrect notion that limiting time with people outside our households could damage our ability to fight diseases may stem from the “hygiene hypothesis,” or the idea that young children who are exposed to germs are less likely to develop allergies and autoimmune conditions. But this concept does not apply to adults, whose immune systems have already been strengthened by exposure to bacteria, according to MIT Medical, a clinic at the Massachusetts Institute of Technology.

While the hygiene hypothesis is probably also the cause of the false assumption that hand sanitizer and hand-washing weaken our immune systems, scientists at the Cleveland Clinic say there is no evidence that temporarily increasing these hygiene routines is damaging.

Anne Liu, an infectious-disease doctor and allergist/immunologist at Stanford Medicine, told Women’s Health that people should make sure to moisturize their hands while they are washing more frequently, since dry, cracked skin can make it easier for bacteria to penetrate.

Fact: Scientists believe the coronavirus originated in animals

Claims that the coronavirus was man-made in a Chinese laboratory continue to circulate, despite virologists and public health officials repeatedly explaining that the virus’s genome suggests it is naturally occurring in nature. Others have suggested that the virus accidentally leaked from a lab that was studying bat-borne pathogens in Wuhan, the city where the coronavirus originated.

The Post’s Fact Checker investigated these theories in the spring and found that most scientific evidence strongly supports the conclusion that the virus was not manufactured. Immunologist and microbiologist Kristian Andersen, who published a study on the virus’s origins, said at the time that his research shows that the coronavirus “is not a laboratory construct or a purposefully manipulated virus.”

Trevor Bedford, a researcher in computational biology and infectious diseases at Fred Hutchinson Cancer Research Center, told the Fact Checker that the coronavirus’s genome does not indicate that chunks of genetic material were inserted or removed, as would be the case if humans had altered it.

Top international and U.S. public health officials — including the World Health Organization, the CDC and the Office of the Director of National Intelligence — have also made clear that evidence indicates the virus is naturally occurring.

As for the idea that the virus may have leaked from a lab accidentally, the Fact Checker concluded that it was an unlikely possibility still under exploration by intelligence agencies. While escape from a lab would require many unexpected coincidences, the Chinese government has not been forthright in addressing questions about the role of its Wuhan labs.

Fact: Urging high-risk people to stay home and letting everyone else live normal lives would not “solve” the crisis

Putting aside the moral and ethical questions at play, isolating the vulnerable and allowing other people to go about their usual business has significant pitfalls. Post columnist Megan McArdle outlined some of the issues, including that hospitals would probably still be overwhelmed by lower-risk people and that it is nearly impossible to keep high-risk people from interacting with others.

While many younger people may have asymptomatic or mild cases of covid-19, the illness can be serious for others. Patients 49 and younger made up 23.1 percent of U.S. covid-19 hospitalizations in the week ending Nov. 21, CDC data shows. And while people with underlying conditions are much more likely to be hospitalized or die, CDC figures from June show that 7.6 percent of patients without underlying conditions were hospitalized.

Letting people interact freely, as if there were no pandemic, would enable the virus to travel through the population even more quickly, straining the capacities of already overwhelmed hospitals and burned-out health-care workers.

Isolating the vulnerable is also not practical. As McCardle points out in her column, roughly 21 percent of U.S. adults 65 and older live in a multigenerational household, as do many people with preexisting health conditions.

Angela Fritz and Derek Hawkins contributed to this report.

Coronavirus: What you need to know

Vaccines: The CDC recommends that everyone age 5 and older get an updated covid booster shot. New federal data shows adults who received the updated shots cut their risk of being hospitalized with covid-19 by 50 percent. Here’s guidance on when you should get the omicron booster and how vaccine efficacy could be affected by your prior infections.

New covid variant: The XBB.1.5 variant is a highly transmissible descendant of omicron that is now estimated to cause about half of new infections in the country. We answered some frequently asked questions about the bivalent booster shots.

Guidance: CDC guidelines have been confusing — if you get covid, here’s how to tell when you’re no longer contagious. We’ve also created a guide to help you decide when to keep wearing face coverings.

Where do things stand? See the latest coronavirus numbers in the U.S. and across the world. In the U.S., pandemic trends have shifted and now White people are more likely to die from covid than Black people. Nearly nine out of 10 covid deaths are people over the age 65.

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