The following is from the Diocese of Sacramento website:

We’ve received several questions about flu season and whether or not Bishop Soto is planning to suspend the common cup for Communion.

In order to determine whether or not to temporarily suspend the cup, we closely monitor the California Department of Public Health’s weekly Influenza surveillance report. When the CDPH has determined that influenza-like illnesses (ILIs) have exceeded the epidemic threshold, the Bishop will notify you about suspending the cup for Holy Communion.

As of their most recent report, however, CDPH determined that the incidence of Influenza like illnesses is “widespread” and “above expected levels for this time of year” but has not reached the epidemic threshold. In the meantime, everyone should take care and be prudent about receiving the cup and making contact with others.

Please remind your parishioners that if they are not feeling well they should abstain from the cup and avoid shaking hands at the kiss of peace. You may assure them that “since Christ is sacramentally present under each of the species, communion under the species of bread alone makes it possible to receive all the fruit of Eucharistic grace.” [Catechism, 1390].

Related: No obligation to attend Mass if you’re sick (Oakland Diocese)