Dozens of migrant children at Long Beach, Pomona centers treated for COVID-19

About four dozen migrant children being housed at an intake center at the Long Beach Convention Center have tested positive for COVID-19, along with 14 more at the Pomona Fairplex.

All are in isolation and receiving on-site medical care, federal officials confirmed.

As of Wednesday, the Long Beach center was housing 710 migrant children, and 47 of them have tested positive for COVID-19, according to Zhan Caplan of the U.S. Department of Health and Human Services, which operates the sites. A total of 67 children were in isolation, with Caplan noting that siblings are kept together.

"The cases are either all asymptomatic or very mild symptoms,'' Caplan told City News Service. "The children are getting excellent care from UCLA Health, our medical provider.''

At the Pomona Fairplex site, where 216 children were housed as of Wednesday, 14 children have tested positive for COVID and were being housed separately, according to Bonnie Preston of HHS.

"We have a team of infectious disease experts from the (U.S. Centers for Disease Control and Prevention) on site who are working with program leads to implement CDC COVID-19 protocols as the site gears up and the census grows,'' Preston said.

RELATED: First group of migrant children arrive at Long Beach Convention Center

Migrant children arrive at Pomona Fairplex

She noted that most of the COVID cases at the location -- and at other HHS intake centers -- were children who arrived with the virus, testing positive when they left the custody of the Border Patrol. They were then taken to intake centers in separate vehicles, she said.

"Once here they remain separate from the other children,'' she said.

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The Pomona Fairplex site began welcoming migrant children Saturday. The children arrived unaccompanied at the U.S.-Mexico border, and are taken to one of various HHS intake centers until they can be reunited with family or placed with sponsors. The Pomona site can hold as many as 2,500 children.

The Long Beach site opened a week prior to the Pomona location. It has the capacity to hold about 1,000 children.