The city began closing public schools the week of March 15 and placed home orders for all but important workers the following week. Restrictions remained in place until June, when the city gradually began to reopen, keeping indoor dining and other high-risk businesses off-limits.
Amesh Adalja, an infectious physician and senior researcher at the Johns Hopkins Center for Health Security, said it is not surprising that shutdowns will slow the spread of coronavirus.
But it is crucial to also look at “the whole picture”
He cited, for example, the impact that restrictions may have had on the ability of mentally ill patients to go to group therapy, or the effect on the degree of vaccination against measles.
“The proof of its ability to reduce cases of covid-19 is not proof that it is a go-to tool,” Adalja said, adding: “It is just a blunt tool that can only be used in a very short time. period in serious circumstances. You end up causing a lot of safety issues that you will have to solve along the way. The key is to think about public health measures in the long run. What is sustainable? ”
Masks also played a major role in limiting the spread, the researchers found.
The forthcoming study showed that the widespread use of face clothing was linked to a 7 percent reduction in transmission during the first month the mandate was implemented in public space.
“But this effectiveness varied very significantly across different age segments of the population,” said Wan Yang, assistant professor of epidemiology at Columbia Mailman School.
Facial coating helped reduce transmission by approx. 20 percent among people 65 and older compared to less than 10 percent for most other age groups.
These numbers reflect the reality that people do not always wear their masks consistently or correctly.
Yang, the lead author of the study, said it is not surprising that older populations had more effective mask behavior compared to younger people who may choose comfort over mask conformity.
“The elderly, they know, they know [higher] risk, so they are more willing to wear face masks properly when outside, ”she said, adding:“ Just after personal observation, they tend to be more careful. Sometimes I saw some older people wear two stitches, just to cover all the bases. ”
If other age groups could model the masking behaviors of older adults, universal face clothing could reduce virus transmission by up to 32 percent, the researchers wrote. There is “certain room for improvement” in mask-wearing, Yang said.
Improving mask wear will be key as the city continues to reopen, and as more people move out after months of staying home, Yang said, especially to “reduce the risk of a new flare-up of covid for places that were able to get it under control and now reopens and tries to regain normalcy after a severe period of the pandemic. ”
Jeffrey Shaman, professor of environmental hygiene science at Columbia and co-author of the study, said in a statement, “It is vital that we find ways to increase uniform and proper mask use in settings where social distance is not possible.”
The researchers used city data on case numbers and deaths as well as mobility data from SafeGraph, a company that collects mobile phone location information, to simulate the spread of coronavirus and estimate transmission. The study was published on MedRxiv, a non-peer-reviewed research preprint server.
The results are particularly noteworthy as the state of New York, once the U.S. epicenter of coronavirus, moves forward with its reopening phases. All the regions of the state have entered phase 4 with reopening. For the first time in months, New York City eateries will be able to dine within restaurants in late September.
The new investigation into New York’s shutdown measures also comes when a federal judge this week ruled that restrictions ordered by Pennsylvania Gov. Tom Wolf (D) to curb the spread of coronavirus were constitutional. President Trump, who had repeatedly threatened Democratic governors of state restrictions, welcomed the decision, saying he hopes it will be followed by similar decisions in other states.
Adalja said that even when they were implemented in New York, home orders were a “last resort because so many mistakes were made in January and February and March. Hospitals were exceeded. We had no ability to know who was infected and who was not. ”
Yang said research has shown that shutdowns work to limit virus spread, even though they are an undesirable strategy.
Nobody wants a lockdown, right? So when it is implemented, it is really critical, ”she said. “Our studies show that it is very effective, especially for covid. It’s really hard to spot. Once you have discovered a significantly high infection rate in a population, chances are we already have broad transmission of communities. ”
Looking ahead, Yang said that in addition to improved masking, there should also be public health protocols, including contact tracing, limiting occupancy in companies and testing and insulation, while reducing the risk of a flare-up.
Public announcements, Yang said, including about the importance of facial coatings, are critical.
“What can you do to prevent another lockdown? We are all in the same boat, so we should communicate that everyone’s efforts count, ”she said. “This is not about individuals. For it to work, we as a society must act collectively. ”