What the science says about the mental health impact of quarantine
Length of isolation, financial stress, and leadership are all key factors. And while the effects are often mild, they can be severe and long-lasting for some (especially health workers).
The coronavirus is grinding life to a halt in cities around the world. China was the first to impose a massive lockdown. Italy, France, and Spain have since done the same. In the U.S., the Bay Area imposed a seven-county lockdown, and New York City has considered a “shelter in place” order of its own.
At present, such severe measures seem necessary to slow the rapid spread of the disease and buy time for hospitals to prepare for a surge in patients. But as Michael Kimmelman writes in the New York Times this week, interventions this severe run counter to the very foundations of urban life, and social isolation carries health consequences of its own.
To get a sense of the mental health impact of disease-related quarantines and other severe restrictions, a group of psychologists at King’s College London conducted a thorough review of the science, released in late February in the journal Lancet. The work focuses on 24 qualitative and quantitative studies on this topic; from this group, I’ve focused on a smaller subset of studies looking at recent respiratory outbreaks, including SARS, MERS, and swine flu.
The upshot isn’t pretty. While the mental health toll of quarantine or isolation during an outbreak is mild for many people, it can be more severe for some groups (especially frontline health workers), with signs of depression or PTSD — and it can last for months or even years. Still, understanding the key factors driving these impacts can help local leaders do a better job mitigating them now, or at least treating them later.
That’s where things get a little brighter: some of the measures needed to reduce the psychological toll are already in motion, the most important being financial support. But many leaders are still struggling to provide the consistent communications and clear timelines that, the evidence suggests, are also important to reducing the mental impact of quarantine.
As in last week’s look at the effectiveness of social distancing measures in 1918, I’ll mention the caveats up top. The coronavirus isn’t like previous outbreaks, so a one-to-one comparison is imperfect. The many social and cultural factors in play limit how widely the results can be applied, as does a lack of focus on elderly populations. Most critically, these studies reviewed strict quarantines; the health impacts are likely less severe in places where people are allowed to make essential trips or even take short walks.
The impact was generally mild but sometimes long-lasting
It’s no surprise that quarantine is mentally tough on people: it’s an extremely restrictive type of intervention that dates back to the plague. Across many studies, the Lancet survey found many indicators of a mild psychological impact from quarantine, such as boredom, a blue mood, or irritability. Stress, insomnia, anger, and exhaustion were also common.
Take one study of Toronto-area residents who lived through a SARS quarantine in 2003. Of 1,057 people who experienced quarantine and responded later to a standard health assessment, the most common self-reported impacts included feelings of boredom (62 percent), isolation (61 percent), frustration / annoyance (54–58%), general worry (40 percent) and loneliness (38.5 percent). This was the case even though compliance with the full quarantine measures was low.
It’s worth noting that 5 percent of study participants felt happy during the quarantine (how their friends or employers felt in response to this news isn’t reported).
There’s also evidence that some of these milder effects lingered long after the quarantine ended. In a study of more than 1,600 Koreans in several areas (including Seoul) who were isolated in response to a MERS outbreak in 2015, researchers found signs of anxiety and anger from self-report assessments. These symptoms decreased over time, but they remained present in some folks even 4 to 6 months after isolation or quarantine.
Perhaps most interestingly, multiple studies found that the experience of a quarantine or isolation led people to change their day-to-day behavior over the long term.
In the Toronto-area SARS study mentioned above, for instance, a quarter of the study participants avoided crowded places and one in five avoided all public spaces in the weeks after the quarantine was lifted. Other evidence from Toronto during this time found that, among quarantined individuals, a return to normal behavior around handwashing and crowd interaction took many months — and, in some cases, was “permanently altered.”
Some impacts were more severe — especially for health workers
In some cases, the mental health impact was more severe, often involving signs of PTSD or depression. That was the troubling finding of a study that looked at nearly 400 parents living in places hit hard by the H1N1 virus (swine flu) in 2009. These households represented cities or suburbs in six U.S. states, Toronto, and Mexico City. About 20 percent of respondents had been ordered into isolation, with 4 percent being fully quarantined.
The impact of quarantine or isolation was striking. Based on self-reports, 28 percent of parents in isolation or quarantine met the diagnostic criteria for PTSD — compared to just 6 percent of parents who hadn’t experienced such restrictions. The same trend held in parental reports of children living through isolation or quarantine, with 30 percent of children meeting a clinical measure of PTSD, compared to just 1 percent of non-quarantined children.
The study didn’t interrogate why these impacts occurred, but confusion and disruption from the norm likely played a role. As one parent (who was also a healthcare worker) put it:
I’m now suddenly working 20 hours a day and isolating myself, and away from them, and wearing a mask when we’re close and not hugging and not sleeping, they can’t crawl into bed with you. That was tough, that was the toughest, the hardest part….
Indeed, frontline health workers such as that participant seemed to suffer more than most. These workers obviously bear a tremendous psychological burden during outbreaks. They’re expected to remain calm and care for others, all while facing much higher risk of transmission from exposure. Indeed, several studies found the mental toll on health workers quarantined during outbreaks sometimes lasted for years.
One study of 549 Beijing hospital workers during the 2003 SARS outbreak found that being quarantined was a predictor of post-traumatic stress symptoms three years later — with these respondents two or three times more likely to have high symptoms than those who weren’t quarantined. A second study of the same population found symptoms of high depression three years after quarantine. A third study of this group found a link between quarantine and symptoms of alcohol abuse three years on.
As the Lancet authors put it, such findings reinforce the need to provide health workers with “special attention” both during and after an outbreak.
A key factor: length of quarantine
The previous sections outlined the nature and severity of psychological impacts resulting from quarantine during an outbreak. But the studies reviewed by the King’s College London researchers also provide insight into some of the key factors that help determine these health outcomes. Little surprise, one of the biggest factors was a quarantine’s duration.
The most instructive study on that front is yet another look at the impact of a SARS quarantine in the Toronto area in 2003. The research team issued online questionnaires to 129 people who’d been given a voluntary quarantine request that involved not leaving their homes.
The study revealed some fairly significant mental health impacts, with symptoms of PTSD in 29 percent of respondents and symptoms of depression in 31 percent. But when the researchers dug deeper, they found measurable variations based on the duration of the quarantine.
On PTSD assessments, study participants who’d been quarantined for more than 10 days had a mean score of 24 (a score of 20 indicates clear symptoms) — significantly higher scores than those quarantined for fewer than 10 days, whose average score was 12. A similar trend existed for measures of depression, with those in quarantine more than 10 days having higher scores than those fewer than 10 days (17 to 11, respectively, with 16 indicating clear symptoms), though this variation didn’t reach statistical significance.
In short, people quarantined more than 10 days suffered measurably more than those quarantined less than 10 days. Now, that doesn’t necessarily mean 10 days is the most people can handle in isolation; we’d need a lot more data to find a true pivot point. But it does suggest, according to the Lancet authors, the need for government leaders to restrict the length of the quarantine “to what is scientifically reasonable given the known duration of incubation periods.” They also caution against extending a quarantine period midstream, given the potential for a person to feel frustrated or demoralized.
They conclude:
Imposing a cordon indefinitely on whole cities with no clear time limit (such as has been seen in Wuhan, China) might be more detrimental than strictly applied quarantine procedures limited to the period of incubation.
Perhaps the biggest factor: Financial stress
The other very big factor in mental health outcomes for those facing isolation or quarantine during an outbreak was financial stress. Again, not a big surprise, but it’s an important factor to document — and it’s likely to be an even greater factor during the coronavirus outbreak than it has been in the past, given the global economic fallout that’s accompanying the current crisis.
Take one study of nearly 200 workers in Beijing, which was placed under mass isolation during the 2003 SARS outbreak. Even 7 to 8 months after the rule was lifted, a standard mental health assessment found evidence of psychological disorder in about a quarter of all respondents. Of these folks, income reduction was the factor with the highest link to mental suffering — more strongly connected than any other factor they tested, including restrictions on going outside, food options, and activity options.
The psychological toll of financial strain also came through in the Toronto-area SARS study mentioned in the previous section. That study found increased PTSD and depressive symptoms in households with a combined income below $40,000 CAD (in 2005 currency), relative to households with higher income levels.
Together this evidence suggests that the economic measures currently being considered by the U.S. government — sending money directly to people — should ease the psychological toll as well as the financial one, provided these payments arrive in a timely manner. That’s of course especially important for people who don’t get paid leave or who lose work as a result of the virus.
Other key factors: boredom and leadership
More than a third of the studies reviewed by the Lancet team found that boredom played a role in psychological distress during quarantine. The potential remedies here are equally unsurprising but still important. For those who can’t leave the house at all, contact with friends, family, and colleagues is essential — and there was evidence that quarantine support groups also helped in Taiwan during the SARS outbreak.
To the extent that isolation orders allow for the occasional safe walk outside, that can help ease the frustration. A stroll through a park or green area may be the best option of all, given nature’s long-established ability to refresh a tired mind, reduce stress, and improve mental health. (And if a walk is impossible, even looking at a desk plant for a bit has been shown to help.)
A final, related factor that plays an important role in mental health during mass quarantine or isolation efforts is leadership — specifically with respect to communications. The studies reviewed in Lancet found negative effects on mental health as a result of mixed messages on health risks from various levels of government, confusion around isolation guidelines (as was initially the case in Spain), and lack of transparency around the severity of the outbreak.
As the Lancet authors write: “Ensuring that those under quarantine have a good understanding of the disease in question, and the reasons for quarantine, should be a priority.”
Steps toward “tolerable”
Overall, the evidence on the psychological impact of outbreak quarantine is, in the words of the Lancet authors, “wide-ranging, substantial, and can be long lasting.” These findings obviously don’t mean cities shouldn’t implement quarantine, isolation, or other severe measures to slow the spread of coronavirus; the health toll of a more widespread disease might be even worse.
Still, the mental health impact is a reason to handle such measures very carefully, to impose less restrictive social distancing measures if possible, and to prepare the proper post-quarantine support programs if not. The authors conclude:
If quarantine is essential, then our results suggest that officials should take every measure to ensure that this experience is as tolerable as possible for people.
Given all that’s happening right now, many of us would gladly endure a “tolerable” spring to beat the current threat — and there are clear steps local leaders can take to help us move forward, while staying still.
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