Experts answer your questions about why Sacramento is moving away from coronavirus quarantines
As Placer County’s health officer, Dr. Aimee Sisson, did the math, she realized that quarantining those exposed to the new coronavirus was not going to contain the spread of the disease.
This realization hit Sisson as she and her team investigated a case of COVID-19 in a Placer County resident who had returned home Feb. 21 from a cruise to Mexico aboard the Grand Princess. The respiratory illness wasn’t diagnosed until March 3, however, so for 11 days, other local people could have been infected.
While researchers have put the maximum incubation period for COVID-19 at 14 days, Sisson said, studies out of China show the average incubation may be four. Sisson said she had found six COVID-19 cases related to the Grand Princess cruise ship, with more tests pending.
“If you think about how many periods of four days there are in 14 days,” Sisson said, “and if you think about every person with COVID-19 having the potential to spread it to...two to three people on average, and each of our sick people spreading it to two to three people who then spread it to two to three more people four to seven days later, you can see that this quickly grows exponentially literally, and so that’s why we are concerned and are now saying the virus is now in our community.”
Other public health officers in the region came to the same conclusion as the U.S. Surgeon General, Dr. Jerome Adams, and Dr. Anthony Fauci, head of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health: Quarantines of asymptomatic people will not contain COVID-19.
Local and national leaders say we need to move from the containment phase to the mitigation phase, and that means the public, businesses, nonprofits, religious organizations and all other entities must change behavior.
As local public health officials announced this pivot in strategy on Monday and Tuesday, Sacramento residents emailed The Bee and sent social media messages saying they were stunned that officials were ending mandatory 14-day quarantines for those who had been exposed. They described the decision as reckless.
The decision won applause, however, from Gerald Parker, who served as an assistant secretary for preparedness and response at the U.S. Department of Health and Human Services. He said that containment can work with a small number of cases out, but mitigation is what’s needed when it’s spread to the community.
“We’ve got to treat it (the spread of the new coronavirus) more than we would when we were trying to put out a little spark,” said Parker, an associate dean in Texas A&M University’s College of Veterinary Medicine & Biomedical Sciences. “Before it becomes a raging forest fire, there are things we do like putting fire lines to try and break the fire from spreading. That’s really what mitigation strategy is. We’ve gone from the spark to a regional fire that we’re putting up fire lines around to stop it. Sometimes it jumps beyond the line, and we have to draw a bigger line.”
That bigger line, Sisson and Parker said, may come in the former of greater restrictions on events and movements, but the local public health departments have begun by recommending critical steps that epidemiologists say can keep the virus from spreading. Sisson, Parker and Dr. Peter Beilenson, the health services chief for Sacramento County, answered questions about the shift in strategy.
Parts of their responses are paraphrased and condensed.
Whose idea is this?
Parker: This isn’t something that public health officials just made up. This two-phase approach is based in public health science, and the United States has used it to mitigate the impact of epidemics at least since 2006 when the nation confronted the H5N1 avian flu pandemic.
Why end quarantines of those exposed to the virus?
Beilenson: Public health investigators have been aggressively identifying and investigating close contacts, quarantining them and monitoring them. Although there have been only 10 confirmed cases in Sacramento county, the public health staff also has been monitoring hundreds of people who returned from travel abroad.
Parker: The nation is at an inflection point, so there’s about to be a significant change in the number of cases.
China took draconian measures when they reached their inflection point, sealing off an entire province from the rest of the nation and mandating all people to stay in their homes unless performing essential duties.
They essentially quarantined Hubei province. Now public health leaders would never do something that aggressive in the U.S., but they are trying to get close to that kind of impact.
Right now, they’re telling people to avoid large crowds where people cannot put at least an arm’s length of space between themselves. This is especially crucial for elderly individuals or people with serious health conditions. They are advising churches to reduce the number of events and eliminate elements of the service that would allow the new coronavirus to spread.
Sisson: Essentially, public health officials are telling those showing symptoms of respiratory illness to quarantine themselves. It doesn’t matter if you have a cold or the flu, COVID-19 or even allergies. Stay home if you’re showing symptoms and for a few days after symptoms have ceased
U.S. public health officials start by making recommendations, but if those recommendations don’t reduce the rate of transmission, local residents should expect to see more aggressive actions such as canceling events, closing schools and even restricting some movement.
Won’t asymptomatic people expose others?
Parker: The data from China show that the symptomatic people are the primary drivers of transmission, but undoubtedly, there is some asymptomatic transmission occurring, too. That’s why the mitigation strategies are so important.
If you’re in a vulnerable population, you should avoid going to large gatherings because other people at the large gathering may be asymptomatic and spreading.
The purpose of mitigation is to try to avoid exposure because there probably is some transmission by undiagnosed cases in the community, and those people don’t even know it.
At the same time, sick people must mitigate the risk of spreading COVID-19. Chinese researchers have published peer-reviewed studies in the Journal of the American Medical Association showing that each visibly sick individual passes the virus to 2.3 people. That means two to three people.
For the safety of everyone around you, stay home if you’re sick.
How do you know these measures will work?
Parker: That’s actually a really, really, really good question. After studying this over a long time, we know the things that people do to avoid exposure and reduce transmission work.
It’s true, though, that concepts like social distancing are largely based on epidemiological mathematical modeling. It’s pretty good modeling, though.
And, again, China provides an example of what can happen when non-pharmaceutical interventions are aggressively implemented. The vast majority of COVID-19 cases and deaths occurred in Hubei because Chinese officials barred people there from moving to other parts of the country.
Then they restricted movement within the province, and now they’re seeing the number of cases decline.
Do you expect the health care system to be overwhelmed?
Parker: The H1N1 pandemic provides a good window into that. That virus at the time spread around the world in just four, five or six months. In Mexico, it was associated with a pretty high mortality rate.
Here in the United States, young people in their prime – teenagers and 20-somethings – became critically ill. Tragically, there were a number of families who lost young sons and daughters, but overall, H1N1 didn’t kill as many people as some had feared.
The nation’s hospital systems were stressed in some communities, but not nationwide.
Now let’s look at the current challenge. Everyone talks about how 80 percent of people will have mild symptoms or no symptoms, and that’s true. But 14 percent of people fall into this category of severe, and 5 percent fall into this category of critical.
Most of the severe actually require some level of hospital care, and that critical category actually requires intensive critical care. That could represent a very high burden on our hospital systems. That’s where you could see problems in individual communities – not everywhere in the United States – but in individual communities.
Sisson: Public health officials don’t want a surge in cases, but it’s not so much to prevent a hospital surge, I want to prevent as many cases as possible.
Again, 80 percent of people are going to have a mild illness, but it’s the 15 percent with severe and 5 percent with critical illness. The more people that are infected, then the larger that proportion is going to get.
We’re trying to keep the total number of cases down, which will prevent the surge, but the surge prevention is a secondary impact.
How do you care for at-risk people?
Sisson: Ideally, the most vulnerable will stay home so that they’re not going to be exposed to the virus, and if someone who lives with a vulnerable person develops symptoms, the sick person should keep their distance. Wear a mask in the house or even consider staying somewhere else because they really are most at risk.
If you have a multi-generational household with lots of people coming in and out, consider limiting visitors and asking the vulnerable person to remain in their room.
There are studies out of China, one of them showed a death rate of 15 percent for people over 80 who had contracted COVID-19. People need look no further than Washington state and what happened with one case in a nursing home. There was one death but now more than 20 deaths.
Public health officials are trying to prevent that by letting people know the virus is here. Everybody needs to take extra precautions and wash their hands like it matters because it does.
In some cases, the alarm is warranted. But again, the message is: Turn anxiety into action. Have a plan. Wash your hands. Stay home when you’re sick. That’s one of the biggest messages being emphasized.
Why not close our borders, restrict U.S. travel?
Parker: Viruses do not respect borders. That is fundamental public health science.
In effect, though, we did close our border to China with the travel ban. The effect was only temporary. It prevented foreign nationals from Hubei province from coming into the United States. It was controversial, but it bought the nation some time to prepare.
Virtually every nation is dependent on the rest of the world for trade. Manufacturers, grocers, pharmacies and hospitals depend on supplies such as raw materials, food and medicines from overseas.
Without certain medical devices and drugs, people would die from diabetes, heart disease and other ailments. You would have to shut down all of the supply chains. It’s just impractical.
Who will be responsible if this strategy doesn’t work?
Parker: Everyone will be.
Editor’s note: This article was updated Thursday to correct that Placer County has found six cases related to the Grand Princess cruise, not to the cruise ship passenger who died.
This story was originally published March 11, 2020 at 1:31 PM.
