Two years

Without widespread testing and surveillance, said Angela Rasmussen, a virologist at Columbia University in New York, “we won’t be able to quickly identify and isolate cases in which the patients are presymptomatic or asymptomatic, and thus community transmission could be re-established.”

Without a vaccine, the virus is expected to circulate for years, and the death tally will rise over time. [...] Only when tens of thousands of antibody tests are done will we know how many silent carriers there may be in the United States. The C.D.C. has suggested it might be 25 percent of those who test positive. Researchers in Iceland said it might be double that. [...] There may be good news buried in this inconsistency: The virus may also be mutating to cause fewer symptoms. In the movies, viruses become more deadly. In reality, they usually become less so, because asymptomatic strains reach more hosts. At the moment, however, we do not know exactly how transmissible or lethal the virus is. But refrigerated trucks parked outside hospitals tell us all we need to know: It is far worse than a bad flu season. [...] If Americans pour back out in force, all will appear quiet for perhaps three weeks. Then the emergency rooms will get busy again. [...] The virus will blossom every time too many hosts emerge and force another lockdown. [...] The tighter the restrictions, experts say, the fewer the deaths and the longer the periods between lockdowns. [...] Reopening requires declining cases for 14 days, the tracing of 90 percent of contacts, an end to health care worker infections, recuperation places for mild cases and many other hard-to-reach goals. [...] Immunity will become a societal advantage. “Those with antibodies will be able to travel and work, and the rest will be discriminated against.” [...] Soon the government will have to invent a way to certify who is truly immune. [...] The California adult-film industry pioneered a similar idea a decade ago. Actors use a cellphone app to prove they have tested H.I.V. negative in the last 14 days, and producers can verify the information on a password-protected website. [...] The next two years will proceed in fits and starts, experts said. As more immune people get back to work, more of the economy will recover. But if too many people get infected at once, new lockdowns will become inevitable. To avoid that, widespread testing will be imperative. [NY Times]

South Korea is trying to solve a mystery: why 163 people who recovered from coronavirus have retested positive [...] the proportion of cases that retest positive is low, 2.1% [...] For now, the most likely explanation of why people are retesting positive seems to be that the test is picking up remnants of the virus.

There are, practically speaking, three paths out of the coronavirus crisis, to a way of life that resembles the one interrupted by COVID-19. The first is a vaccine. The second is effective treatment for the sick — not just effective at the margin, but so effective that catching the disease becomes a considerably less worrisome prospect for even those with comorbidities. The third is through herd immunity, when enough of the population has acquired COVID-19 antibodies that even with a return to “normal” life, there wouldn’t be enough opportunities for disease transmission for the virus to continue circulating through the population. You have probably heard quite a lot in the past few weeks about testing — in particular the need to deploy widespread testing and possibly what’s called “contact tracing” alongside it, to identify not just those who are sick but those they’ve been in contact with, as well. But a widespread testing regimen — or those “test and trace” programs — isn’t a path out of the pandemic, only out of lockdown. [...] The most optimistic projection for vaccines is that they begin to be available this fall; other reputable estimates suggest between one and two years from now. [NY mag ]

On 4/3-4/4, 2020, we tested county residents for antibodies to SARS-CoV-2 using a lateral flow immunoassay. [...] the population prevalence of COVID-19 in Santa Clara ranged from 2.49% (95CI 1.80-3.17%) to 4.16% (2.58-5.70%). [...] The population prevalence of SARS-CoV-2 antibodies in Santa Clara County implies that the infection is much more widespread than indicated by the number of confirmed cases. [medRxiv]

Seattle: We estimate that the average population prevalence between March 23 and April 9 was 0.24% [95% CI 0.05% - 0.75%]. [PDF]

How does coronavirus kill? Clinicians trace a ferocious rampage through the body, from brain to toes

world's biggest trial of drug to treat Covid-19 begins in UK (over 5,000 test subjects)

Our study shows that non-pharmaceutical interventions (including border restrictions, quarantine and isolation, distancing, and changes in population behaviour) were associated with reduced transmission of COVID-19 in Hong Kong, and are also likely to have substantially reduced influenza transmission in early February, 2020. [The Lancet]

Nearly half of the roughly 2,300 sailors from France’s Charles de Gaulle aircraft carrier group have tested positive for the coronavirus [To compare with: “The Diamond Princess cruise ship represented the worst-case scenario in terms of disease spread ... only 20% were infected." previously posted here]

Epidemiologists still don’t know the worldwide death rate for Covid-19

The “case fatality rate” of covid-19 varies wildly from country to country and even within nations from week to week.

One in five people globally could be at increased risk of severe COVID-19 disease through underlying health conditions

DeRisi soon realized that he had stumbled onto a snake pandemic whose origin remained entirely uninvestigated. He ordered up some dead snakes so that he might play around with their genome in the same way that, back in 2003, he’d analyzed human genomes after people were killed by a mysterious new coronavirus that had surfaced in Hong Kong. (SARS, the new virus was being called.) To work the same magic on snakes that he did on humans — that is, to separate the genetic material that was “python” from everything else, he needed to know the python’s genome. “Who founded the Python Genome Project?” says DeRisi. “No one!” And so DeRisi took some of his graduate students to the San Francisco aquarium, extracted the blood of one of its snakes, and began what amounted to the Snake Genome project. Once he was done, he was able to take the genetic material of an infected snake, eliminate everything that was “snake,” and thus isolate what wasn’t snake: the virus. “It was actually an ancient ancestor of Ebola,” says DeRisi. “Dinosaurs had this same virus.” [...] DeRisi is now the co-president of the Chan Zuckerberg Biohub, a nonprofit organization created a few years ago with a $600 million gift from the Facebook Inc. founder Mark Zuckerberg and his physician wife, Priscilla Chan. [...] On March 12, DeRisi decided to turn the Biohub into a coronavirus testing lab. [...] Eight days after the 200 volunteers started building the new UCSF testing lab, the Biohub was up and running. Since March 20, it’s been able to process 2,500 tests a day, at no cost. Quest Diagnostics, one of the biggest diagnostic labs in the country, was saying that if you sent them a test, it would take them a week to get back to you with an answer, along with their bill. In just one day more than it took Quest to process a single test, DeRisi built an entire lab that could process 2,500 of them. A day. For free. [Bloomberg ]
China revises its figures in Wuhan, adding 50 percent more deaths

Chinese officials on Friday said that the world’s second-largest economy shrank 6.8 percent in the first three months of the year compared with a year ago, ending a streak of untrammeled growth that survived the Tiananmen Square crackdown, the SARS epidemic and even the global financial crisis. The data reflects China’s drastic efforts to stamp out the coronavirus, which included shutting down most factories and offices in January and February as the outbreak sickened tens of thousands of people. The stark numbers make clear how monumental the challenge of getting the global economy back on its feet will be. Since

Wuhan’s 11 Million People Are Free to Dine Out. But They Aren’t.

The dating industry was poised to take a hit amid the coronavirus outbreak as potential suitors are generally unable to meet in-person. Platform Match, which also owns Tinder and OkCupid, has seen stocks tumble 25%. But daters are turning to digital courtship through video chats and virtual activities as an alternative. [AXIOS]