The Federal Correctional Institution has 38 inmates with positive tests, five more than on Tuesday.
Staff members who tested positive add up to 14 across both facilities, a number that remained unchanged.
The prison has logged six inmate deaths linked to COVID-19 since the start of the pandemic.
Lompoc has suspended visitation at both facilities during the latest outbreak.
The Lompoc federal prisons aren’t the only facilities dealing with COVID-19 outbreaks.
At the Santa Barbara County Jail, three new inmate cases were reported on Tuesday, the latest in an outbreak that started Dec. 8.
Jail officials have reported 221 positive cases in the outbreak, with 191 people having since recovered.
At the California Men’s Colony in San Luis Obispo, the state-operated men’s prison reported 112 active cases with 131 new in the past 14 days.
For staff, current active staff cases total 183, all of them reported in the past 14 days.
CMC also has had 13 deaths attributed to COVID-19.
The state prisons have suspended visitation until at least Sunday, but have expanded video visiting, according to the California Department of Corrections and Rehabilitation. Information about the status can be found here.