HMO Plans Choose Altais Medical Group: HMO Plans To confirm whether your Altais Medical Group physician participates in any of these HMO plans, please refer to the health plan websites listed below. Aetna 800-756-7039 aetna.com Anthem Blue Cross 800-677-6669 anthem.com/ca Blue Shield 888-568-3560 blueshieldca.com Cigna 800-244-6224 cigna.com Health Net 800-638-3889 healthnet.com UnitedHealthcare 800-624-8822 uhc.com View all Insurances Accepted