Coronavirus cases are skyrocketing. Here’s what it will take to gain control
November is beginning to feel a lot like last March.
In Europe, where the coronavirus was largely under control for much of the summer and fall, cases are skyrocketing nearly everywhere. Twenty countries, including the United Kingdom and France, have shuttered restaurants, introduced curfews or generally urged people to stay at home, though most schools and universities are staying open for now.
Cases are surging across the United States, too, where more than 100,000 new infections are being reported each day. Already in November, more than half of states have set records for the most cases in a week, and in places such as Minnesota, Utah and Wisconsin, some hospitals are nearing capacity. In North Dakota, nearly 1 in every 14 people has already contracted the coronavirus, with 2,254 cases reported November 8 alone in a state of 762,000 people.
To make matters worse, “the virus is going into its sweet spot at a time that we’re exhausted by it,” says Jeffrey Shaman, an infectious diseases epidemiologist at the Columbia University Mailman School of Public Health in New York City. That sweet spot is indoors, where people are spending more time as the weather in the Northern Hemisphere turns colder — and where the virus can spread more easily.
Despite such a grave outlook, experts say it’s still not too late to turn the tide.
Shutting down borders, businesses and schools are among the most drastic measures to do that. Worries over economic consequences may hold governments back from issuing widespread stay-at-home orders this time around, though.
U.S. President-elect Joe Biden, who unveiled a COVID-19 advisory board November 9, has proposed a multipronged plan for controlling the pandemic, including nationwide mask mandates and expanded testing. But Biden won’t take office until January 20, and President Donald Trump has repeatedly downplayed the surge in cases.
While getting a COVID-19 vaccine — or vaccines — is closer than ever (SN: 11/9/20), most experts agree that vaccines probably won’t be available to everybody until late spring or early summer.
That means getting through the winter will require falling back on the familiar public health tools of physical distancing, mask wearing, and testing and isolating infected people, Shaman says. But all of those measures fall short unless everyone is willing to follow the rules.
Living in this reality can be draining, acknowledges Aleksandra Zając, a doctor specializing in nuclear medicine in Warsaw. Doctors and patients alike are tired of not being able to leave their homes and having to wear a mask when they do, she says, but “as a doctor, I really see the need for all those restrictions.” People aren’t helpless against the virus, she says. “We still have some impact on what’s going on.”
Zając devised a calculator to help people learn how much wearing masks and goggles, regularly washing their hands and keeping distance from others might help protect them. Alone, none of those measures is perfect, but doing them all together can boost protection, like layering slices of Swiss cheese so that holes in one slice are covered by another slice. The Swiss cheese idea is not new, but it’s still relevant for stacking public health measures, Zając says. It goes for individual actions, too.
“One individual cannot do much” beyond protecting themselves, Zając says, “but if we sum up all the individuals together and they all follow the rules, I truly believe we can control this pandemic.”
Scientists know much more about the virus than they did in March, and that knowledge can help make the most of all the public health tools at our disposal.
Mask up
Dozens of studies have made it abundantly clear that wearing a mask is one of the most effective steps an individual can take to help curb the pandemic. Masks are especially crucial in lessening the risk of someone who doesn’t know they’re infected passing the virus to someone else (SN: 6/26/20).
For example, if 95 percent of people wore masks when outside their homes, nearly 130,000 deaths from COVID-19 might be averted in the United States between the end of September and the end of February 2021, researchers reported October 23 in Nature Medicine. If 85 percent of people wear masks, about 96,000 lives might be saved, the researchers calculated.
The debate over which kind of mask is best, however, has been spirited (SN: 8/12/20).
When it comes to ubiquitous cloth masks, only one randomized clinical trial in the world is testing their effectiveness in preventing COVID-19. That trial in Guinea-Bissau is giving all 66,000 expected participants advice about how to avoid respiratory illnesses. Half of those people will each also get two locally sewn cloth masks. The trial is expected to wrap up in November.
Some research on the prevention of other respiratory illnesses suggests that a cloth mask’s effectiveness depends on many factors, including wearing the mask properly over both the nose and mouth. Regular washing in hot water is also necessary, says Raina MacIntyre, a mask researcher at the University of New South Wales in Sydney.
In 2015, she and colleagues published in BMJ Open results of a trial conducted in Hanoi, Vietnam. Roughly 1,600 health care workers at 15 hospitals were assigned to either wear a medical mask at all times during their shift, to wear a two-layer cloth mask or to follow the hospital’s standard practice, which may or may not involve wearing a mask. The results weren’t encouraging. At the end of the five-week study, people in the cloth mask group had the highest rate of respiratory infections, such as colds — even higher than the group that wasn’t regularly wearing masks. The researchers concluded that health care workers shouldn’t wear cloth masks and opt instead for medical masks.
The trial was very controversial, MacIntyre says, “because the message was that cloth masks could be dangerous. That caused a lot of angst during the pandemic. In March and April, I had a lot of health workers in the U.S. and Europe contacting me and saying, ‘The hospital has run out of respirators. Is it better I wear no mask than wear a cloth mask?’”
That prompted MacIntyre and colleagues to examine unpublished data from the trial. Both surgical and cloth masks get contaminated with respiratory viruses, the researchers found. But surgical masks are disposable. If people didn’t wash their reusable cloth masks every day, the masks became more and more contaminated.
“If you washed your cloth mask in a washing machine with hot water, you were just as protected as wearing a surgical mask,” MacIntyre says. But workers who hand-washed their masks had double the risk of infection of those wearing a medical mask, the researchers reported September 28 in BMJ Open.
“The bottom line is, the washing is part of the protective effect of a cloth mask,” MacIntyre says. She recommends a daily wash in water at 60° to 90° Celsius, far hotter than anyone could stand to hand-wash. Shrinkage from hot water also tightens up pores in the mask, keeping the virus from slipping through easily.
Health care workers should also wear protective goggles to prevent rare cases of infection through the eye, MacIntyre says. But determining whether people going about their daily lives need goggles, face shields or other eye protection in addition to masks is a tricky bit of calculus, she says. “You have to look at community transmission rates. You have to look at where you’re actually going. Are you just going for a walk outside or are you going to a doctor’s surgery and are going to be sitting in an unventilated waiting room for two hours?”
The best most people can do is to take all the precautions they can, including avoiding large gatherings — especially indoors — wearing masks and keeping distance from people they don’t live with.
Fine-tuning lockdowns
Early in the pandemic, lockdowns and social distancing measures (of varying severity) enacted in many countries largely worked. Staying at home starved the virus of transmission opportunities, preventing over 500 million infections in six hard-hit countries, according to some experts (SN: 6/9/20).
Circumstances are different now. “I don’t think we’ll lock down at that scale again,” says Michael Osterholm, an epidemiologist at the University of Minnesota in Minneapolis and a member of Biden’s task force. Now that scientists have a better understanding of transmission, blanket lockdowns may not be needed. Instead, restrictions could focus on crowded, poorly ventilated spaces like restaurants and bars.
If cases continue to grow exponentially, however, stricter lockdowns may be the only tool left to prevent hospitals from being overwhelmed. But such measures are increasingly less palatable to many Americans, Osterholm says. “What the public will accept is key. If they won’t comply, it doesn’t really matter what you recommend or how you recommend it.”
Limits of lockdowns
Stay-at-home orders also don’t stop transmission within a household, where experts are learning that the virus can rapidly spread. In a sample of 101 homes with a positive coronavirus test, 53 percent of other people living in those homes became quickly infected, researchers reported in the Nov. 6 Morbidity and Mortality Weekly Report.
“We know that it’s really gatherings in close contact indoors that are riskiest,” says Alison Hill, an epidemiologist at Johns Hopkins University. “There’s no reason why if you’re in your own house or among family or friends to think that the disease can’t spread.” Isolating infected members of a household, wearing masks and improving ventilation can limit household transmission, she says.
And not everyone can stay home, which has contributed to inequities in who is getting sick in this pandemic.
In the United States, residents of poorer neighborhoods, often home to racial and ethnic minorities disproportionately affected by COVID-19 (SN:4/10/20), were less likely to stay at home during the early months of the pandemic than residents of richer neighborhoods. Cell phone mobility data suggest that this difference stems from work-related demands, according to a study published November 3 in Nature Human Behavior. Residents of the highest-income neighborhoods reduced days at work outside the home by 13.7 percent, compared with 6.6 percent for residents of lower-income neighborhoods, Jonathan Jay, a public health researcher at Boston University, and colleagues found.
Many residents of lower-income neighborhoods work jobs that can’t be done from home. But when there was a choice, people in these neighborhoods did limit their activities, Jay says. The data showed that people of all income groups reduced outings unrelated to work at roughly similar levels.
Policies like restricting evictions so people don’t fear losing their home if they miss work, expanding unemployment insurance and mandating paid sick leave could help these residents physically distance, Jay says.
Test and trace
Lockdowns by themselves will not end the pandemic. They are only supposed to be temporary measures that buy time for local and state health departments to beef up other infection-control strategies. Crucial among these are testing and contact tracing, a tried-and-true public health intervention whereby contacts of positive cases are quickly identified and instructed to quarantine (SN: 4/29/20).
“Contact tracing is really key when you have a disease that’s as fast-spreading as COVID-19,” because it breaks crucial chains of transmission, says Martial Ndeffo, an infectious diseases researcher at Texas A&M University in College Station.
Contact tracing and isolation is most powerful when cases are identified early in the course of infection, their contacts are traced and informed of their exposure quickly, and those contacts comply with requests to quarantine. Such a system requires broadly available testing and lots of contact tracers to do the detective work.
Otherwise, even with relatively small caseloads, contact tracing systems can’t keep up with a growing epidemic. At this point, most of the United States can’t keep up. In October, only three states and the District of Columbia had enough full-time contact tracers to deal with current caseloads, according to a survey conducted by NPR and the Johns Hopkins Center for Health Security. And as cases climb, even well-staffed systems could be overwhelmed.
“Given the number of cases in the U.S., it is unrealistic to think that most states have the resources and available staff to raise the army of contact tracers needed,” Ndeffo says. Biden’s COVID-19 response plan includes efforts to “mobilize at least 100,000 Americans across the country” to boost the contact tracing effort. Currently, there are just over 50,000 contact tracers nationwide.
Robust contact tracing systems work only if people comply with public health officials and share their contact history or quarantine if necessary. Yet only 58 percent of Americans would be likely to speak with a public health official who contacted them by phone or text message about the coronavirus outbreak, according to a Pew Research survey released October 30. “A substantial number of people do not comply with or provide adequate information needed for contact tracing to be effective,” Ndeffo says. Clearer and more consistent public health messaging could improve these numbers.
Time is of the essence
It’s important to act quickly to introduce social distancing measures when case counts begin to surge, as they are now in the United States and Europe, Shaman says, because outbreaks grow at exponential rates. “Exponential growth leads to a tsunami-like effect; it gets worse the longer you wait on it.”
He and colleagues simulated what would have happened had states done exactly what they did at the beginning of the U.S. epidemic in March, only earlier. Enacting social distancing and stay-at-home orders on March 1 instead of March 8 would have headed off about 600,000 confirmed cases and 32,000 deaths. Acting two weeks earlier would have avoided more than 1 million cases and about 60,000 deaths nationwide, Shaman and colleagues reported November 6 in Science Advances.
No one can turn back the clock. But countries including Vietnam, Taiwan, Singapore, New Zealand and Australia have shown that acting aggressively can curb the spread of the virus. “Going forward, the longer you delay in acting on this virus the more damage it does,” both to people who are infected and to the economy, Shaman says.
For instance, at the end of September, 89 counties in Tennessee eased or removed social distancing restrictions. But as COVID-19 cases rose, traffic to bars and restaurants decreased, researchers from Vanderbilt University in Nashville report. Cell phone mobility data as of October 21 suggest that business dropped once restrictions were lifted and was 24 percent below where it was during the same time in 2019. Those findings suggest that infection rates, not restrictions, have a bigger effect on people’s choices, the researchers conclude.
“If you don’t control the virus,” Shaman says, “you’re not going to have an economy.”
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