Patients in the confirmed and probable cases had contact with sick cows at nine different farms.
At least two doses of the novel oral polio vaccine type 2 are needed to interrupt transmission
California also reported a seventh potential case, as the CDC shared updates, including the latest genetic sequencing results.
The two patients experienced eye symptoms and have no known connections to the state's three earlier confirmed cases.
Like two recent California cases, the patient had conjunctivitis after working with sick cows.
Along with updates on recent human infections, federal officials detailed new awards for H5 vaccines, which will double the doses slated for the national stockpile.
The patient experienced conjunctivitis after contact with infected dairy cattle in the state's Central Valley.
Idaho's agriculture department says dairy herds are quarantined in four of the state's counties.
California has reported 63 West Nile virus infections this year, including many in the Central Valley.
The latest local dengue case in Los Angeles county isn't related to the cluster reported earlier this month.
