Airborne transmission is the main way the new coronavirus spreads, and wearing a mask is the most effective way to stop person-to person spread, according to a new study by a team of researchers in Texas and California.
The researchers, led by Renyi Zhang from the department of Atmospheric Sciences at Texas A&M University, compared Covid-19 infection rate trends in Italy and New York both before and after face masks were made mandatory. Both locations started to see infection rates flatten only after mandatory face masks measures were put in place.
They calculated that wearing face masks prevented more than 78,000 infections in Italy between April 6 and May 9, and more than 66,000 infections in New York City between April 17 and May 9.
“Wearing of face masks in public corresponds to the most effective means to prevent interhuman transmission, and this inexpensive practice, in conjunction with simultaneous social distancing, quarantine, and contact tracing, represents the most likely fighting opportunity to stop the COVID-19 pandemic,” they wrote in a report published Thursday in the Proceedings of the National Academy of Sciences .
The researchers undertook their analysis to gauge the effectiveness of different strategies for stopping the spread of infection and to determine how the virus is mainly spread. Viruses can spread by direct contact when a person coughs or sneezes on another person; indirect contact, when a person coughs or sneezes on an object that is then touched by another person; or in the air via large droplets that fall quickly to the ground and tiny droplets, called aerosols, that can travel several feet and hang in the air for a while.
To figure out how the virus is mainly transmitted, the researchers analyzed trends in the infection rates in three epicenters — Wuhan, China; Italy; and New York City. They also looked at mitigation measures that were being used in those locations, such as extensive testing, quarantining, contact tracing, social distancing and mandatory use of face masks.
Then they compared the timing of when those measures were put in place. In China, all of the measures were put in place at the same time. In contrast, New York and Italy saw different measures being put in place at different times. This allowed the researchers to assess their relative effectiveness.
They found infection rates in Italy and New York City only started to slow after face masks were made mandatory, not after lockdown was put in place in Italy or after stay-at-home orders went into effect in New York.
There has been much confusion about the effectiveness of face masks.
“Advice on the use of face masks was not issued until April 6, 2020 by the WHO, claiming that it is important only to prevent infected persons from viral transmission by filtering out droplets but that it is unimportant to prevent uninfected persons from breathing virus-bearing aerosols,” Zhang and colleagues wrote. When people wear face masks, they are protecting others more than they are protecting themselves.
But the researchers said the evidence shows masks work to slow spread.
“Face covering prevents both airborne transmission by blocking atomization and inhalation of virus-bearing aerosols and contact transmission by blocking viral shedding of droplets,” they write. “On the other hand, social distancing, quarantine, and isolation, in conjunction with hand sanitizing, minimize contact (direct and indirect) transmission but do not protect against airborne transmission.”
Brazil surpassed 800,000 total confirmed Covid-19 cases Thursday, according to figures released by the health ministry.
The health ministry reported 30,412 new cases in the past 24 hours, bringing the country's total to 802,828. This is the third day in a row Brazil has recorded a daily spike of at least 30,000 new cases, the health ministry said.
Brazil's Covid-19 death toll also topped 40,000 Thursday, after recording 1,239 new deaths in the past 24 hours.
Brazil's coronavirus death toll stands at 40,919.
Georgia Gov. Brian Kemp signed a new executive order today, easing more restrictions across the state.
The order goes into effect on June 16 and lasts through June 30, according to a statement.
Here's what can further reopen:
The food industry shares the blame for both the obesity pandemic and the severity and consequences of Covid-19, according to an editorial published Thursday in the BMJ.
The authors, who are from Queen Mary University in London, highlight the link between obesity and serious illness and death from Covid-19.
Studies show that for people who were overweight, the risk of critical illness increased by 44% and the risk of death increased by 27%. Studies also showed the risk of both critical illness and the risk of death nearly doubled for people who were obese, the authors wrote.
Obesity also affects immune responses and lessens lung function.
Because of this, food industries worldwide must change the way that they are reacting to the pandemic and governments must support healthier food habits, the group argued.
“The food industry has launched campaigns and corporate social responsibility initiatives, often with the thinly veiled tactics using the outbreak as a marketing opportunity,” they wrote.
During the pandemic, there have also been many issues surrounding food, which include an increase in food poverty and disruptions in the supply chain. This may have limited access to fresh food, forcing people to eat more food that is processed or high in salt, sugar and saturated fat.
With 65% to 70% of the United States and United Kingdom populations being overweight or obese, the effects of Covid-19 have made it clear that these changes from the food industry and from governments need to be made, the authors say.
A US Centers for Disease Control and Prevention team is scheduled to arrive Friday in Northwest Arkansas, said Dr. Nate Smith during a news conference on Thursday.
“Their goal is to help us to better understand the dynamics of transmission in the northwest part of the state, particularly in Washington and Benton counties, helping to understand this interplay between transmission in the home, in the community and in the workplace. We are hoping that those insights will better enable us to break those cycles of transmission,” Smith said.
Smith said 29% of active cases in the state were in the Latino community and on Tuesday, 24% of our hospitalized patients were in the Latino community.
The Arkansas Department of Health reported 10,816 cases of Covid-19 cases and 171 deaths in the state.
Smith said there are 3,294 active cases, with 140 in nursing homes, 199 in correctional facilities and 2,955 in communities.
Arkansas Gov. Asa Hutchinson said he believes he made the right decision to lift restrictions and to move the state into phase two on June 15 despite the number of Covid-19 cases rising.
“Even though we are opening up and expanding our economy that does not diminish the seriousness of this virus,” he said.
The coronavirus pandemic is killing on average 1,000 Americans a day and 4,000 globally, and this should not be the new normal, Dr. Tom Inglesby, the director of the Bloomberg School’s Center for Health Security, said at a news briefing Thursday.
Some states have hundreds or even thousands of new Covid-19 cases every day and Inglesby pointed out that countries like New Zealand and Thailand have driven their cases down to zero.
“Are we resigned to losing 1,000 Americans a day, until we have a vaccine?” he asked. “I hope we aren’t.”
“We can do these things in the US and should be,” Inglesby added.
He referenced a study this week from the University of California at Berkeley that found that stay-at-home orders alone have prevented more than 62 million coronavirus infections in the US so far and 530 million in the six other countries studied.
“Social distancing works,” he said, noting that in some places around the country people are letting their guard down, moving “too rapidly to open the economy at the risk of accelerating the spread of the disease.”
He also warned that he considers indoor gatherings one of the continued dangers of catching and spreading the virus.
“I think the things that are going to be higher risk are longer periods of time indoors with others that are not part of your family and you breathing in the air that they’re exhaling. If you’re at close distance, that’s going to pose higher risk,” he said.
“The concern is we don't know whether or not kids in schools will accelerate the spread within those institutions and then transmit the disease to both teachers or administrators who are older, or to their family, parents, grandparents at home,” he said.
Sao Paulo state authorities announced an agreement between the Brazilian Butantan Institute and Chinese laboratory Sinovac Biotech to conduct phase three of a clinical coronavirus vaccine trial on approximately 9,000 volunteers in Brazil starting the first week of July.
"The vaccine proved very effective at phase two. It really protected against all infections. Now we are going to do a populational test. It is a promising vaccine, without a doubt,” Butantan Institute President Dimas Covas said while speaking at a news conference Thursday.
Phase three will involve trying the vaccine on different types of people that represent the diversity of the population such as by age or ethnicity.
According to Sao Paulo´s health officials, the vaccine went through the first two phases of testing in China, where it was tested on 744 volunteers. The Chinese lab started human clinical trials with the experimental vaccine on April 17.
The agreement establishes that the Butantan Institute will own the vaccine technology to potentially mass-produce it inside Brazil; and if proven effective, it is expected to be available to the population in the first half of 2021, according to Covas.
The Butantan Institute is one of Brazil's top biomedical research centers.
The state of Sao Paulo is the epicenter of the outbreak in Brazil with 162,520 cases of coronavirus and 10,145 deaths as of Thursday afternoon. Brazil has the second highest cases in the world; the US is first, according to Johns Hopkins University.
Italy is further easing its coronavirus lockdown measures to allow professional sporting events, such as the Coppa Italia football match, to resume behind closed doors starting Friday, Prime Minister Giuseppe Conte said in a news conference Thursday night.
Other establishments can also reopen starting June 25, including summer camps, kindergartens, betting rooms, and bingo halls, Conte said, announcing that he had just signed a decree that eases further the lockdown measures. Non-professional sports that involve physical contact may also resume.
Local officials will be able to assess the viability of restarting these activities given the number of coronavirus cases in each region. Fairs, convention centers, and nightclubs with dancing will not be permitted to restart their activities until July 14.
Italy has been on a nationwide lockdown since March 9.
Conte also announced the expansion of Italy's contact tracing program. Starting Monday, a contact tracing app that has been tested in four regions will be implemented nationwide.
“Citizens can download the app in great security...it protects privacy," Conte said. “We are proud of this app that grants a further service to citizens and we were the first in Europe to have reached this result that is very sophisticated from a technical point of view."