Every day, Isidoro Flores Contreras stands at the edge of a parking lot in Sand City selling $15 bouquets of flowers. And every evening, he returns to a small apartment that he shares with four other people.

Flores Contreras, who makes about $300 a week, is highly vulnerable to the coronavirus — both at work, which he had to stop until Monterey County’s health order was eased, and at home.

He lives in the most crowded ZIP code in Monterey County, sleeping in the living room of a two-bedroom apartment. His housing conditions put him at high risk: The millions of Californians who live in overcrowded houses are more likely to be infected with the coronavirus, according to an analysis of health data by The California Divide, a statewide media collaboration.

The hardest-hit neighborhoods have three times the rate of overcrowding and twice the rate of poverty as the neighborhoods that have largely escaped the virus. And the neighborhoods with the most infections are disproportionately populated by people of color.

About 6.3 million Californians, or 16%, live in overcrowded housing. A third of those, 2.1 million, inhabit severely overcrowded housing. California has the second-highest rate of crowded households in the nation, about 2.5 times higher than the nationwide rate.

About two-thirds of the people who live in these crowded homes — some 4 million people — are essential workers or live with at least one essential worker. Health experts say this creates a perfect storm for the coronavirus: people crowded together in homes at night and spending days working on the front lines, exposed to a lot of people both at work and at home.

Hot spots for overcrowded homes are spread throughout California, including the Salinas Valley, Oakland, Los Angeles and desert towns near the US-Mexico border.

Monterey County, home to many farmworkers, leads the state in overcrowding with one in every seven households crowded. In Monterey and San Benito counties, nearly one in 10 households, the highest rate in the state, are both overcrowded and include an essential worker.

During a pandemic, this can be deadly.

Crowded communities hit hardest

Flores Contreras lives in the Alisal, a Mexican and Mexican-American community in Salinas where 61,000 people are squeezed onto a parcel of land less than three square miles.

The Alisal, where 22% live in poverty, is the center of the coronavirus outbreak. About 31% of patients in Monterey County diagnosed with COVID-19 live in the 93905 ZIP code, even though just 14% of the county’s population lives there.

Many, like Flores Contreras, live doubled or tripled up, which heightens the risk of transmission. In the 93905 ZIP code, where the Alisal lies, 31% of homes are crowded. An average of 4.5 people live in each household.

The Census Bureau defines overcrowding as a home with more people than rooms, while a home with more than 1.5 people per room is severely crowded. California’s overcrowded homes are due, in part, to the sky-high cost of housing. Nearly a third of California renter households spend more than half their income on rent.

In Monterey County’s eleven ZIP codes, the five areas most heavily burdened by the virus had 2.5 times more crowded housing than areas with the fewest people diagnosed, as of June 8.

Drive 22 miles west from the Alisal, and you’ll arrive in Carmel-by-the-Sea, a wealthy hamlet of fewer than 4,000 people on the edge of the Pacific. Here, the median income is almost $91,000 and just 3.9% of homes are crowded. Fewer than five people (the county’s reporting cutoff) have been diagnosed with COVID-19, compared with 233 in the Alisal’s ZIP code as of June 9.

Oakland is another area with wide disparities, based on which neighborhood people live in. In the ZIP code that contains the affluent Montclair neighborhood and Piedmont city, just 1% of homes are overcrowded. Fewer than one in every 1,000 residents tested positive for the coronavirus there. But across town, in majority Latino neighborhoods like Fruitvale, the infection rate was six times higher as of late May and 21% of homes are overcrowded.

An April analysis of New York City emergency department data found neighborhoods with more residential overcrowding tended to have more emergency department visits for influenza-like illness in March compared with the previous four years.

“What we’ve been generally seeing is very high transmission rates within a household. … You can imagine if there’s less space, if people have to share room, it’s going to be really hard to isolate people,” said Justin Feldman, an NYU social epidemiologist who conducted the research.

Neighborhoods with more foreign-born residents, poverty and Latino residents had the biggest increases.

“And who do we know is living in crowded housing?” asked Feldman. “People who are lower income, they’re more likely to be immigrants, more likely to have to go to work.”

Essential workers stuffed into homes

Social distancing is especially hard for essential workers, who must leave their homes regularly to keep the rest of the United States fed and sheltered.

According to an analysis by the Public Policy Institute of California, essential workers are more likely than nonessential workers to live in overcrowded housing — 16% versus 12%. More than a third of California’s labor force works in essential jobs that mean they must be physically present, such as farming, fishing or forestry. Nearly a third of farmworkers and people who work in restaurants live in overcrowded homes.

Crowded housing also puts Latinos at higher risk. Latino households are nearly eight times as likely as white households to be crowded.

At the low-income health clinic where Dr. Efrain Talamantes works in Los Angeles, most patients arriving with coronavirus symptoms are essential or service workers, Latino, low-income and live in crowded housing.

“Patients who live in places where there’s no privacy …  when you tell someone to get in a room and stay away from their loved ones, it’s almost nonsense to them,” said Talamantes.

He said patients are often just as worried about staying housed as they are about the virus, and fear being evicted if their landlord finds out they’ve contracted COVID-19.

“What we’re most concerned about is how this virus is going to exacerbate inequalities in communities where we’ve made so much progress since the last recession. It really takes a toll on the communities they’re in,” Talamantes said.

In Los Angeles, as many as two in every five households are overcrowded in some neighborhoods. The areas most heavily burdened by COVID-19 had twice the rate of crowded housing as the areas least hard hit.

Ricardo Hernandez and his family of five live in West Adams, a neighborhood in South Los Angeles where 83% of residents are Latino or black, in a two-bedroom home his parents purchased years ago. In West Adams, about 17% of households are overcrowded, and there were about seven coronavirus cases for every 1,000 residents in late May, almost three times the statewide rate of 2.6 per 1,000.

For months, Hernandez, his wife and two sons shared one bedroom, while his mother, a diabetic, and his brother, a kidney transplant survivor, shared the other. Because of their health problems, they are both highly vulnerable to severe effects if they are infected with the virus.

“We remove our shoes before entering the house, we disinfect door knobs often and we wash our hands as much as we can,” said Hernandez.

Although it was hard, Hernandez said it had been beneficial to stay at home together during the pandemic.

“I feel this is a mental, moral cure and a peace of mind because we know how we are doing when we see each other,” he said.

‘I can’t fly to the moon’

For California’s farmworkers, crowded housing is the norm, whether it’s a rental unit, a farmworker shelter, or employer-provided, barracks-style housing.

On the northern edge of the Salton Sea in Riverside County, Gloria Gomez runs the Galilee Center, a boarding house for farmworkers who stay in Mecca for just months at a time.

The pandemic has completely changed their operations. The center expanded its hours to 24 hours a day, provides three full meals a day instead of two and stopped charging farmworkers the usual $7 a day for room and board. Staff moved the beds six feet apart, reduced residents and cleans the dorms every two hours.

Gomez said many of the farmworkers have caught the coronavirus from another relative in the home, unable to properly quarantine themselves in too-small housing. In recent weeks, Mecca had three farmworkers die from COVID-19, according to the Desert Sun.

Enrique Reyes, a farmworker in Mecca, has one of the coveted 34 farmworker beds at Galilee Center.

Before the pandemic began, he fought with his wife and moved out of the two-bedroom Salton City trailer they share with their two kids and two grandchildren. But now, he said, he doesn’t want to move back for fear of bringing the virus into their home, and he can’t miss work.

“Nada es cien por ciento,” said Reyes. “¿Qué más puedo hacer? No me puedo ir a la luna ni llevar mi familia a la luna. Tengo que seguir las reglas como todas las personas.” In English, “Nothing is certain, but what else can I do? I can’t fly to the moon or take my family to the moon with me. I have to just follow the rules like everybody else.”

J. Omar Ornelas of the Desert Sun, Jacqueline Garcia of La Opinión and Matt Levin of CalMatters contributed to this story. This article is part of The California Divide, a collaboration among newsrooms examining income inequality and economic survival in California. Kate Cimini at The Californian reported this story with support from the California Fellowship through the USC Annenberg Center for Health Journalism.