If you wish to travel to the United States a B1 or B2 visa are both still valid. Nonetheless, the EVUS is an additional requirement under U.S. Immigration law in addition to the B1, B2 or B1/B visa.
The EVUS visa is meant to compliment your 10-year B1/B2 Visa. All individuals who travel to the United States should complete this requirement before departure. As of November 29, 2016 if you hold a 10-year B1, B2 or B1/B2 it is compulsory that you update your personal information every two years in the EVUS system.
Please note that the EVUS is not a visa as it does not meet the legal requirements to serve as one. To apply for an EVUS you must have a valid US visitor visa class B1, B2 or B1/B2. Once your EVUS is revised and approved it will be valid for multiple trips for two consecutive years unless the visa or the passport expire, whichever comes first.