Some Californians face substantial risk of illness within their own households under the state’s shelter-in-place order. Physical distancing and self-isolation can be virtually impossible in crowded homes, threatening the health of entire households. In crowded living conditions, individuals are at higher risk of transmitting infectious diseases, a factor that may challenge the state’s efforts to manage the pandemic while reopening the economy.

As the high cost of housing is a stark reality for nearly two-thirds of Californians, finding affordable housing can mean cohabiting with several other people. California’s overcrowding rate is well above the national average; the share of housing units with more than one occupant per room is 8.3% compared with 3.4% across the nation. Furthermore, overcrowding is much more common among renters than homeowners (13.4% vs. 4.0%), and in Latino households (18.4% vs. 2.4% of white households).

While most Californians have been staying home to reduce coronavirus transmission, essential workers do not have the option to shelter in place. Over one-third of California’s labor force works in essential occupations that require being physically present. Compared to nonessential workers, they are at higher risk of infection because they continue to circulate among others despite the shutdown.

Essential workers are more likely than nonessential workers to live in overcrowded housing—16 percent versus 12 percent. That share is almost double for workers in farming (31%), and food preparation/serving (29%).

A recent study confirms that essential workers and those in larger households do face a higher risk of contracting coronavirus. It would be ideal to explore the relationship between COVID-19 cases and workers living in crowded conditions. However, inconsistent testing availability across regions makes cases an unreliable measure of the virus’s geographic spread; deaths, which are better measured, are a valuable proxy.

There is a clear link between COVID-19 deaths and essential workers who live in overcrowded homes, though the relationship is muddied by regional differences in terms of the age structure of the population,  underlying health conditions, and other factors. Santa Barbara (25%), Madera (23%), Los Angeles (21%), Orange (20%), and Tulare (19%) counties have the highest shares of essential workers in overcrowded homes. Los Angeles and Tulare are experiencing large numbers of deaths per capita, at 14 and 9 deaths per 100,000 people, but the other counties are not.

California will lift some shelter-in-place restrictions in the coming days, and more people will leave their homes to work. Examining work and living conditions together can identify areas where people are least able to take effective actions against the spread of the coronavirus. Designing policies to protect the health of workers and their households will be critical to managing COVID-19 while restarting the state’s economy.