Here's how the eviction crisis could increase the spread of Covid in the US

One of the main ways that state and local governments have tried to slow the spread of the coronavirus is by issuing stay-at-home orders.

Yet sheltering in place is close to impossible for the tens of thousands of Americans who've been evicted during the pandemic.

And the situation could soon get a great deal worse for many more. At the end of the month, the Centers for Disease Control and Prevention's national eviction moratorium will expire, and landlords will be free to push out their tenants.

Without additional government intervention, many families will spend their holidays this year scrambling to figure out where to go if they're evicted. More than 12 million Americans – or 1 in 6 adult renters – were behind on their rent in November. Certain to worsen the situation is the fact that unemployment claims this week were at their highest level in months.

Beyond the devastating personal and financial consequences of an eviction on an individual, a report shows that displaced individuals and families increase the spread of the virus.

Before the CDC halted evictions across the country in September, 43 states had passed their own eviction moratoriums. Yet many of the stays were in place for 10 weeks, or less. North Dakota and Iowa, for example, halted the proceedings for only about a month.

The researchers found that states allowing their eviction moratoriums to expire caused as many as 433,700 excess cases of Covid and 10,700 additional deaths between March and September.

CNBC spoke with two of the study's authors, Kathryn Leifheit, an epidemiologist and postdoctoral fellow at the UCLA Fielding School of Public Health, and Dr. Craig Pollack, an associate professor at Johns Hopkins Bloomberg School of Public Health. We discussed what their findings might tell us about what will happen when the CDC's national eviction ban expires and what should be done to keep families in their homes during the public health crisis.

CNBC: What are the reasons that evicting individuals and families increases the spread of the virus?

Kathryn Leifheit: We know that household crowding is a major risk factor for the spread of the coronavirus. When people get evicted, they often need to move in with friends and family or enter a homeless shelter. This drives up the number of contacts people are having, allowing Covid to spread more easily.

CNBC: What are some of the states that have had the most eviction-related Covid cases and deaths? Why has it been worse in these places?   

KL: We saw the most cases and deaths associated with lifting the eviction moratorium in Texas, where we estimate nearly 150,000 excess cases and 4,500 excess deaths. Two main factors contribute to this: The population – states with more people can develop more cases and deaths – and the date the moratorium was lifted. Lifting earlier allows more evictions to be processed and allows displacement to drive up Covid risk.

CNBC: The federal government moved to halt evictions across the country in September, but that moratorium will expire at the end of the month. If no additional action is taken, what do you expect to happen?

Craig Pollack: The economic toll of Covid has been unrelenting and experts predict an avalanche of evictions if the federal moratorium expires. Our research suggests that this will be associated with a large number of cases and deaths that could potentially be avoided if the moratorium were to remain in place.

CNBC: If the federal government wants to do everything it can to end the pandemic, what kind of housing policies should it implement?

KL: In the short term, we need a strong federal eviction moratorium that extends through the end of the public health emergency. Congress should also address rent relief so that, whenever the moratorium lifts, tenants and landlords have the means to settle back-rent and prevent a mass wave of evictions.

CNBC: I know you've both researched the relationship between housing and health before the pandemic. Besides the risk of contracting and spreading Covid, what are some of the other consequences evicted individuals often face?   

KL: Most of my past research has been on how eviction affects children's health and development. We found that if a pregnant mother is evicted, she's more likely to give birth to a baby that is either pre-term or low birthweight. When children are evicted, they're more likely to experience food insecurity and lead poisoning. They're also more likely to fall behind cognitively.

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