Current Affairs Of Pakistan & World: Coronavirus: When should you mask?

Coronavirus: When should you mask?

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April 20, 2022

An informed guide to the pandemic, with the latest developments and expert advice about prevention and treatment.

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The New York Times

By Amelia Nierenberg

Writer, Briefings

Moderna released trial results that suggest a version of its vaccine designed to target variants offers better, longer-lasting protection.
Officially, Shanghai has recorded just 17 Covid deaths, a figure that revives questions about the way China defines and records pandemic fatalities.
An "epidemic of loneliness" was already affecting our health and life expectancy. The pandemic has made it worse.
Find the latest updates here, as well as maps and a vaccine tracker.

When should you wear a mask?

On Monday, Philadelphia reinstated its mask mandate as cases there rose. (New York City may soon follow.) Hours later, a federal judge struck down the federal mask mandate for planes and public transit.

Since then, it's been an absolute scramble.

Public health experts are dismayed by the ruling, which the C.D.C. said today it had asked the Justice Department to appeal.

Some large U.S. transit systems are keeping mask mandates in place, a decision supported by a new poll. But many airlines quickly complied with the new rules, and Uber ended its U.S. mask requirements. When asked whether Americans should wear masks on planes, President Biden said it was "up to them."

Here's some guidance, taking into consideration your environment, your individual risk factors and those of the people around you — and the fact that masks protect the wearer, even when others around them are mask-free.

Airplanes: A mask is a good idea.

Most planes pump the cabin air through high-efficiency particulate air (HEPA) filters, which work pretty well. But in December 2021, researchers found that passengers sitting in the same row and more than one seat away from someone who had Covid-19 still had a high risk of being infected through direct respiratory droplets. Wearing a mask reduced the risk of infection by 54 percent.

Your seat may not be in the most dangerous spot, either. Boarding and deplaning areas and airports generally may be worse for circulation of the virus. And as experts reminded me: You don't want to ruin your trip by becoming infected and having to quarantine, even if your risk of severe illness remains low.

Public transportation: Probably a good idea.

Unlike a plane, few buses or trains have fancy ventilation systems.

"I know everyone talks about planes, but I would say buses are probably the riskiest, then trains, and then planes, in order of highest to lowest," said Linsey Marr, an expert in airborne transmission of viruses at Virginia Tech.

Schools: It's a tough call.

It's a difficult and deeply personal call for parents, especially when schools or school systems do not have hard and fast mask mandates.

Children very rarely suffer severe symptoms, whether or not they're vaccinated. (Vaccination helps: Unvaccinated children from 5 to 11 years old were hospitalized with Covid at twice the rate of vaccinated children during the winter Omicron surge) Many students have gone to school without masks during the pandemic, and very few children have gotten seriously sick.

The jury is also still out on whether masks impede social development, and several studies do suggest that masks make communication difficult.

Shopping: Depends on the store.

If the business is mask optional, consider the space, the crowds and the airflow.

Take a big box store with high ceilings. "Those tend to have good ventilation, and because of the high ceilings, there's a lot of dilution," Dr. Marr told me.

"If it's a smaller space and crowded space — Trader Joe's, for example, or some New York market with tiny aisles and people are really packed in there — the risk is higher," she continued. "You might want to wear a mask."

And in general: Consider case numbers.

You're not the only person affected by your mask choices.

Take a second to wonder about the risk you pose to others, especially as cases rise. What role does my mask play in protecting others? What is my responsibility to the people around me, especially if I'm healthy?

How dangerous is Covid, really?

Throughout the pandemic, we've all tried to quantify the actual threats we face from the coronavirus, fumbling around with iffy statistical analyses.

Scientists have struggled to make and communicate comparisons as well. The coronavirus remains new enough, and its long-term effects unpredictable enough, that measuring the threat posed by an infection is a thorny problem.

But with the information we have now, my colleague Benjamin Mueller tackled questions of quantifying your individual risk.

Here are some takeaways from a few recent estimates:

War: The average vaccinated and boosted person 65 or older had a risk of dying after a Covid infection slightly higher than that of someone serving for a year in the military in Afghanistan in 2011.
Drugs: An average unvaccinated person 65 or older is roughly as likely to die from an Omicron infection as someone is from using heroin for a year and a half.
Driving: An average 40-year-old vaccinated more than six months ago faces roughly the same chance of being hospitalized after an infection as someone does of dying in a car crash in the course of 170 cross-country road trips.

Any comparison to an average is inherently limited, however, because different groups of people have different vulnerabilities. Children and the immunocompromised, for example, face very different risks:

Children under 5: The risk of dying after a Covid infection was about the same as the risk of a mother dying in childbirth in the U.S. (Importantly, that's a national average; there are large racial discrepancies in maternal mortality statistics.)
Organ transplant patients: An unvaccinated 61-year-old with an organ transplant is three times as likely to die after a Covid infection as someone is within five years of a diagnosis of stage one breast cancer. That transplant recipient is twice as likely to die from Covid as someone scaling Mount Everest.

What you're wondering

How are we testing to track variants effectively? It seems we are only aware of Covid positivity, not what variant of Covid is present. — M. Sorenson, Virginia Beach, Va.

Here's an answer from Emily Anthes, a Times science reporter.

It's true the overwhelming majority of people tested for the virus will never learn which variant they have — those results aren't generally returned directly to patients. But it doesn't mean virus samples aren't being sequenced. A lot of that happens behind the scenes, and a subset of the samples collected for testing at health care facilities and labs is sent for sequencing. Scientists are also using wastewater to track variants — people infected with the virus shed it in their stools, and sequencing samples of wastewater can help us keep tabs on which variants are circulating and how prevalent they are. But it's true there are still lots of infections we're not capturing, especially among people only taking at-home tests. Some scientists worry the shift to at-home tests could create bigger blind spots in genomic surveillance.

What else we're following

Boris Johnson apologized for violating his own coronavirus restrictions but downplayed the act of lying to Parliament, which is considered grounds for resignation under the ministerial code.

School districts are offering incentives like gift cards and night classes to lure chronically absent students back.
Shanghai relaxed lockdown rules for about four million people on Wednesday, The Associated Press reported.
A day after public schools in Milwaukee made masks optional, the district reinstated its mandate, CNN reports.
The Justice Department charged 21 people with coronavirus-related fraud schemes.