The first pictures of the coronavirus, taken just seven months ago, resembled barely discernible smudges. But scientists have since captured the virus and its structures in intimate, atomic detail, offering crucial insights into how it functions.
Less than a millionth of an inch wide, the virus is studded with proteins called spikes that attach to cells in people’s airways, allowing the virus to infiltrate. But under an electron microscope, the proteins look more like tulips than spikes, consisting of long stems topped with what looks like a three-part flower. These spikes also swivel on a three-way hinge, which may increase their odds of encountering and attaching to proteins on human cells.
As the spikes sweep around, they can also be attacked by antibodies. But they are protected by shields made of sugar. Sugar molecules, in navy below, swirl around the proteins and hide them from antibodies.
The coronavirus genome consists of 30,000 letters that hold the information for making its proteins. The genes are arrayed on a molecular strand called RNA.
After the virus enters a human cell, our ribosomes — the tiny cellular factories that pump out proteins — attach to its RNA strands and glide down them like a roller coaster car running along a track. As the ribosomes pass over the genetic letters, they build proteins with corresponding structures.
In just a few hours, an infected cell can make thousands of new virus genomes. Ribosomes read the genes and create more viral proteins, which then combine with the new genomes to make more viruses.
Already, the new pictures of SARS-CoV-2 have become essential for the fight to end the pandemic. Vaccine developers study the virus’s structure to ensure that the antibodies made by vaccines grip tightly to the virus. Drug developers are concocting molecules that disrupt the virus by slipping into nooks and crannies of proteins and jamming their machinery.
But while the past few months have delivered a flood of data about the virus, some studies have made it clear that it will take years to fully make sense of SARS-CoV-2.
Rural India’s hot spots
The coronavirus is spiraling out of control in rural India, where efforts to contain the virus have faced a significant backlash. The situation has put India on track to have the most reported infections in the world: While the nation currently has 6.9 million cases, compared with 7.6 million in the United States, it is adding about 30,000 more cases a day than the U.S.
A sharp contrast divides India’s urban centers, where public health campaigns have helped to quell the virus, and the rest of the country, where many people think the government has exaggerated the pandemic and doesn’t understand their economic hardship. In many villages, people don’t wear masks or practice social distancing. Residents often refuse to be tested, which carries a social stigma, and hide that they are sick.
The surge stems at least in part from India’s strict lockdown in the spring, which prompted millions of migrant laborers to leave urban areas that they could no longer afford. Their exodus to rural communities helped the virus spread across the country.
The consequences are now clear: Rural hospitals are running out of beds and struggling to provide oxygen to patients. In one rural facility’s coronavirus ward, corpses were left for insects to crawl over.
Resurgences
Here’s a roundup of restrictions in all 50 states.
What else we’re following
What you’re doing
My husband and I each picked six of our favorite cities and loaded them into our weather app. Each morning, over coffee, we read the weather to each other for all of these places, talking about what we would do for the day if we were there, and in doing so, often remembering lovely little memories of past visits. A couple of the cities are still bucket list cities, but we’ve certainly learned a lot more about how to choose the best time to go..
— Karyn Todd, Parkland, Fla.
Let us know how you’re dealing with the pandemic. Send us a response here, and we may feature it in an upcoming newsletter.
Sign up here to get the briefing by email.
Email your thoughts to [email protected]. Did a friend forward you the briefing? Sign up here.