MILWAUKEE (SPECTRUM NEWS) — In recent months, the scientific world has seen a steady flow of research updating what we know about the novel coronavirus, SARS-CoV-2, and how it affects humans. Because the virus is so new, researchers are still grappling with many questions about its function. And because of the nature of the scientific process, no single study can completely answer those questions. Instead, new research is constantly challenging our understanding of the pandemic.

Here, we explore some recent studies that have shed new light on the virus. 

 

Masks protect the people wearing them, too

It’s been a common refrain over the course of the pandemic: “My mask protects you, your mask protects me.” 

Public health officials have stressed that masks help keep viral particles in — an important measure for a disease that is often spread by people who aren’t showing symptoms. But last week, the Centers for Disease Control and Prevention wrote in a scientific brief that cloth masks can also keep viral particles out, giving extra protection to the people wearing them.

In addition to stopping respiratory droplets — which are thought to be the main way the virus spreads — on their way out of the wearer’s mouth and nose, “masks also help reduce inhalation of these droplets by the wearer,” the brief states. This means masks can help stop the spread in two ways: “Source control,” or preventing infected people from spreading the virus, and “personal protection,” or helping healthy people stay healthy.

The update reflects growing scientific evidence that even non-medical masks can filter out some infectious droplets. Studies have shown that cloth masks do provide some level of protection, especially if they have multiple layers and high thread counts.

This doesn’t mean you are totally in the clear if you’re wearing a mask: Some particles are still able to get through even high-quality cloth masks, so other measures like social distancing remain important. 

But the dual benefit adds another incentive to follow mask-wearing guidance, John Brooks, chief medical officer for the CDC’s coronavirus response, tells The Washington Post. And that incentive is important since, as the CDC brief says, “individual benefit increases with increasing community mask use” — or the more, the merrier when it comes to covering up.

“Our guidance is still the same,” Brooks told The Washington Post. “This is more data in support of that, and it highlights that there is personal protection that we want to make sure people know about.”

 

Many patients face mental illness after COVID-19 infection 

It’s been well-documented that the coronavirus pandemic has taken a huge toll on mental health. Among COVID-19 survivors, those strains appear even greater: Nearly 20% of patients infected with the virus were diagnosed with a psychiatric illness within three months, according to a new study from the University of Oxford.

That research, published this month in Lancet Psychiatry, analyzed electronic health records from 69 million U.S. patients between January and August, including 62,000 coronavirus patients. 

The authors found that around 18% of COVID-19 survivors experienced anxiety, depression, insomnia, or other mental health problems within 90 days of testing positive. For around 6% of those patients, it was the first time they’d been diagnosed with a mental health disorder.

The high numbers didn’t just come from dealing with health issues in general, or the overall stress of 2020. Compared to patients who were treated in the same time period for other conditions — like influenza, or a broken bone — the COVID-19 patients had double the risk of being newly diagnosed with a psychiatric disorder, according to the study. Coronavirus patients were also at higher risk for dementia.

Interestingly, the risk appeared to run both ways: The study found that a person with a pre-existing psychiatric diagnosis was about 65% more likely to be diagnosed with COVID-19 than one with no history of mental health problems. The authors write that they didn’t anticipate this “bidirectional” connection, and didn’t offer a clear answer as to why it showed up.

Other research has shown that the virus may be able to attack brain cells along with other parts of the body, and many COVID-19 patients have reported long-lasting neurological effects like “brain fog” and loss of smell. So, the high rates of mental health issues post COVID-19 could be related to these attacks on the nervous system. But the apparent connection could also stem from other outside factors, and more research is needed to figure out the true cause, according to the study.

“Equally, it’s not at all implausible that COVID-19 might have some direct effect on your brain and your mental health,” psychiatry professor Paul Harrison, one of the study’s authors, told The Guardian. “But I think that, again, remains to be positively demonstrated.”

 

Household transmission is more common than we thought

If one person tests positive for coronavirus, there’s a good chance they’ll spread it to others in their household — and fast, according to recent CDC research.

The study, published at the end of October, tracked 101 coronavirus patients and their household contacts in Nashville, Tenn., and Marshfield, Wis. For two weeks, all of these participants kept symptom diaries and collected their own samples for testing. 

Out of 191 household contacts — who all reported no symptoms before the study started — around 53% ended up testing positive. In three-quarters of these new cases, the secondary infections showed up within five days of the first household member getting sick.

That’s higher than in previous studies, which estimated household infection rates in the 20% to 40% range. And household transmission was frequent whether the original patients were children or adults, as well as across racial and ethnic groups.

The results highlight the importance of taking quick measures to isolate any infected household members, like having them use a separate bedroom and bathroom if possible.

“Prompt adoption of disease control measures, including self-isolating at home, appropriate self-quarantine of household contacts, and all household members wearing a mask in shared spaces, can reduce the probability of household transmission,” the authors write.

Everyone else in the home should quarantine, get tested, and especially stay away from high-risk individuals, even if they aren't feeling sick.

That's especially important because a majority of the newly infected household contacts in the study were asymptomatic when they first tested positive, and many of them never showed symptoms through a week of follow-up. ​Just because you feel fine, if someone in your home has COVID-19, there are good odds you have it, too — so it's best to be careful, so you don't risk bringing the virus into other homes.

 

Monoclonal antibodies get the OK from the FDA

Even though the U.S. isn’t doing so well at containing the virus, scientists are getting better at treating those who get sick with COVID-19. Last week, the FDA gave its first emergency use authorization for a monoclonal antibody treatment, which aims to help those fending off mild to moderate symptoms.

The treatment, developed by drugmaker Eli Lilly, was approved for use on high-risk patients, like those with underlying conditions or older adults aged 65 and up. Its approval "provides health care professionals on the frontline of this pandemic with another potential tool in treating COVID-19 patients," Patrizia Cavazzoni, acting director of the FDA’s Center for Drug Evaluation and Research​, said in a statement.

This type of antibody treatment gives the immune system an extra boost with lab-created proteins that target the SARS-CoV-2 virus. The body naturally produces its own antibodies to attack invaders, but it can take some time for the immune system to start churning them out — especially in the case of an unfamiliar attacker like the novel coronavirus.

Monoclonal antibodies can help offer protection in the meantime. They’re designed to target the coronavirus’s signature spike protein and prevent the virus from infecting patients’ cells. According to an FDA release, the Eli Lilly antibody was shown to reduce hospitalization and emergency room visits among high-risk patients.

Dozens of similar treatments from other companies are in various stages of development — including one from Regeneron, which was used to treat President Trump when he caught the virus and which is now waiting on FDA approval.

Of course, monoclonal antibodies aren’t a complete solution for the pandemic. Vaccines, which prompt the body to produce its own antibodies, are still important for long-term protection, since the lab-grown antibodies fade out over time. And for patients who are already hospitalized with severe COVID-19 cases, the FDA release says the antibody treatment may actually lead to worse outcomes.

Still, in certain cases, “this might be a lifesaving intervention in people who are unable to mount a strong natural immune response to the virus,” as Texas State University professor Rodney E. Rohde writes for The Conversation.