Environmental News for a Healthier Planet and Life

Help Support EcoWatch

Coronavirus May Wane This Summer, but Don’t Expect the Pandemic to End

Coronavirus May Wane This Summer, but Don’t Expect the Pandemic to End
An aerial view of a notice dug into the sand reading #STAYHOME on Tamarama Beach on April 02, 2020 in Sydney, Australia. James Gourley / Getty Images

By Ellen Wright Clayton

Will SARS-CoV-2, the virus that causes COVID-19, fade away on its own this summer?

After all, other viruses – including influenza and respiratory syncytial virus (RSV), which causes bronchiolitis in little children – are mostly seen in the winter.

The National Academies' Standing Committee on Emerging Infectious Diseases and 21st Century Health Threats recently addressed the question of whether SARS-CoV-2 will follow the same pattern. The group of experts corralled the research that's been done so far – much of it not yet peer-reviewed – to assess the evidence.

While there is some reason to hope that things may get better as the weather warms up, there is plenty of reason for the U.S. to keep its guard up.

Are Heat and Humidity Reason for Hope?

Although the U.S. is early in the course of the pandemic, there is evidence from other countries that SARS-CoV-2 spreads more rapidly in cold, dry weather.

One preprint study of 30 Chinese provinces showed that the number of COVID-19 cases went down by between 36% and 57% for every 1.8 degree Fahrenheit increase in temperature. When temperatures held steady in the low 40s F, the number of cases went down between 11% and 22% with each 1% increase in relative humidity (how much water is in the air).

A larger preprint study looking at 310 regions in 116 countries found that 11% more cases were reported when the temperature went down 9 degrees, the relative humidity went down 10% and when the wind speed went up.

Laboratory research also suggest that the virus survives longer in cold conditions. One study showed that SARS-CoV-2 lasts for 14 days at 40 F in lab media but is gone after one day at 98.6 F.

These and other studies suggest that warm, humid weather may slow the spread of this virus, although not all commentators agree.

New research on this topic appears almost daily, and scientists are watching to see what happens as summer comes to the Northern Hemisphere.

Which Clues Call for Caution?

COVID-19 is already spreading in many parts of the world where it's hot, including Australia and South America, demonstrating that high temperatures are not enough to stop the disease.

The most important reason to be concerned about ongoing spread is the fact that this is a brand new virus for humans, so almost everyone is susceptible to being infected.

In fact, weather actually appears to play a minor role in the rate at which this virus spreads.

Other influences on infection rates include individual behaviors, cultural practices, geography, income and living conditions. Public health practices such as social distancing, the intensity of testing for infection, contact tracing, quarantine of people who are exposed and isolation of people who are actually infected also play a big role in how the coronavirus spreads.

The news from other viral diseases is not encouraging either. The two most serious coronavirus diseases that are closely related to COVID-19, the first SARS outbreak and MERS, did not vary with the seasons after they emerged. In fact, MERS is still found year-round in the Middle East, where it is hot and dry. Pandemic influenza infections have emerged at different times of the year as well.

What Should We Do?

The long-term solution to SARS-CoV-2 will be to develop a safe and effective vaccine. This work is proceeding at unprecedented speed, but it will still take anywhere from months to a few years and will require trials involving thousands of people and massive international leadership and collaboration.

Until there's a vaccine, prevention will require avoiding exposure to people who can spread the virus. Communities need to test people to find out who is contagious and engage in serious contact tracing, quarantine and isolation. Scientists need to learn more about how to determine if someone is immune and how long immunity lasts, a big open question at the moment. As individuals, each of us will need to follow expert scientific advice about good hygiene practices and distancing.

SARS-CoV-2 is likely to keep circulating until the human population has widespread immunity, which hopefully will come not from an unchecked pandemic but from developing and deploying a safe and effective vaccine.

Ellen Wright Clayton is a Professor of Pediatrics and Law and Health Policy at Vanderbilt University.

Disclosure statement: Ellen Wright Clayton reviewed the statement on seasonality by the NASEM Standing Committee.

Reposted with permission from The Conversation.

EcoWatch Daily Newsletter

A resident works in the vegetable garden of the Favela Nova Esperanca – a "green favela" which reuses everything and is subject to the ethics of permaculture – in the outskirts of Sao Paulo, Brazil, on Feb. 14, 2020. NELSON ALMEIDA / AFP via Getty Images

Farmers are the stewards of our planet's precious soil, one of the least understood and untapped defenses against climate change. Because of its massive potential to store carbon and foundational role in growing our food supply, soil makes farming a solution for both climate change and food security.

Read More Show Less
Once the virus escapes into the air inside a building, you have two options: bring in fresh air from outside or remove the virus from the air inside the building. Halfpoint Images / Getty Images

By Shelly Miller

The vast majority of SARS-CoV-2 transmission occurs indoors, most of it from the inhalation of airborne particles that contain the coronavirus. The best way to prevent the virus from spreading in a home or business would be to simply keep infected people away. But this is hard to do when an estimated 40% of cases are asymptomatic and asymptomatic people can still spread the coronavirus to others.

Read More Show Less
California Senator Kamala Harris endorses Democratic presidential candidate Joe Biden at a campaign rally at Renaissance High School in Detroit, Michigan on March 9, 2020. JEFF KOWALSKY / AFP via Getty Images

Former Vice President Joe Biden made a historic announcement Tuesday when he named California Senator Kamala Harris as his running mate in the 2020 presidential election.

Read More Show Less
An aerial view taken on August 8, 2020 shows a large patch of leaked oil from the MV Wakashio off the coast of Mauritius. STRINGER / AFP / Getty Images

The tiny island nation of Mauritius, known for its turquoise waters, vibrant corals and diverse ecosystem, is in the midst of an environmental catastrophe after a Japanese cargo ship struck a reef off the country's coast two weeks ago. That ship, which is still intact, has since leaked more than 1,000 metric tons of oil into the Indian Ocean. Now, a greater threat looms, as a growing crack in the ship's hull might cause the ship to split in two and release the rest of the ship's oil into the water, NPR reported.

On Friday, Prime Minister Pravind Jugnauth declared a state of environmental emergency.

France has sent a military aircraft carrying pollution control equipment from the nearby island of Reunion to help mitigate the disaster. Additionally, Japan has sent a six-member team to assist as well, the BBC reported.

The teams are working to pump out the remaining oil from the ship, which was believed to be carrying 4,000 metric tons of fuel.

"We are expecting the worst," Mauritian Wildlife Foundation manager Jean Hugues Gardenne said on Monday, The Weather Channel reported. "The ship is showing really big, big cracks. We believe it will break into two at any time, at the maximum within two days. So much oil remains in the ship, so the disaster could become much worse. It's important to remove as much oil as possible. Helicopters are taking out the fuel little by little, ton by ton."

Sunil Dowarkasing, a former strategist for Greenpeace International and former member of parliament in Mauritius, told CNN that the ship contains three oil tanks. The one that ruptured has stopped leaking oil, giving disaster crews time to use a tanker and salvage teams to remove oil from the other two tanks before the ship splits.

By the end of Tuesday, the crew had removed over 1,000 metric tons of oil from the ship, NPR reported, leaving about 1,800 metric tons of oil and diesel, according to the company that owns the ship. So far the frantic efforts are paying off. Earlier today, a local police chief told BBC that there were still 700 metric tons aboard the ship.

The oil spill has already killed marine animals and turned the turquoise water black. It's also threatening the long-term viability of the country's coral reefs, lagoons and shoreline, NBC News reported.

"We are starting to see dead fish. We are starting to see animals like crabs covered in oil, we are starting to see seabirds covered in oil, including some which could not be rescued," said Vikash Tatayah, conservation director at Mauritius Wildlife Foundation, according to The Weather Channel.

While the Mauritian authorities have asked residents to leave the clean-up to officials, locals have organized to help.

"People have realized that they need to take things into their hands. We are here to protect our fauna and flora," environmental activist Ashok Subron said in an AFP story.

Reuters reported that sugar cane leaves, plastic bottles and human hair donated by locals are being sewn into makeshift booms.

Human hair absorbs oil, but not water, so scientists have long suggested it as a material to contain oil spills, Gizmodo reported. Mauritians are currently collecting as much human hair as possible to contribute to the booms, which consist of tubes and nets that float on the water to trap the oil.

A northern mockingbird on June 24, 2016. Renee Grayson / CC BY 2.0

Environmentalists and ornithologists found a friend in a federal court on Tuesday when a judge struck down a Trump administration attempt to allow polluters to kill birds without repercussions through rewriting the Migratory Treaty Bird Act (MBTA).

Read More Show Less
A spiny dogfish shark swims in the Olympic Coast National Marine Sanctuary off the coast of Washington. NOAA / Wikimedia Commons

By Elizabeth Claire Alberts

There are trillions of microplastics in the ocean — they bob on the surface, float through the water column, and accumulate in clusters on the seafloor. With plastic being so ubiquitous, it's inevitable that marine organisms, such as sharks, will ingest them.

Read More Show Less


A "vessel of opportunity" skims oil spilled after the Deepwater Horizon well blowout in the Gulf of Mexico in April 2010. NOAA / Flickr / CC by 2.0

By Loveday Wright and Stuart Braun

After a Japanese-owned oil tanker struck a reef off Mauritius on July 25, a prolonged period of inaction is threatening to become an ecological disaster.

Read More Show Less