Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Situational Awareness
Aircraft Equipment Problem Critical; Flight Deck / Cabin / Aircraft Event Illness / Injury; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Air Traffic Control Provided Assistance; Flight Crew Landed in Emergency Condition; Flight Crew Diverted; Flight Crew Overcame Equipment Problem; General Maintenance Action
Aircraft
We departed from ZZZ as scheduled. An hour into the flight; we were cruising at FL380. We received a call from the Number 1 Flight Attendant letting us know that there was an odor in the back of the aircraft that smelled like burning wire. He said he could smell it from about 3 rows from the aft galley. No smoke was seen. The Captain asked about the 2 flight attendants in the back. The Number 1 stated they felt a little nausea and headache; but they were doing okay. At that point; the Captain elected to [advise ATC] and land at ZZZ1. We were about 40nm from ZZZ1. I continued flying while the Captain coordinated with ATC; the Company; and the flight attendants. Captain also made a PA to the passengers. We were given radar vectors to land on RWY XXC. We landed uneventful on [Runway] XXC and stopped on the runway. We talked with ARFF and had them check the aircraft for smoke and anything out of the ordinary. ARFF said they saw nothing and we continued to the gate with ARFF following us. Once parked at the gate; the passengers deplaned. The two flight attendants in the back deplaned and were met by the EMTs and checked out. Maintenance boarded and checked the aircraft for possible sources of the smell. In the end; they said it was a power port that was overheating.  Throughout the event; there was no change reported in the strength of the odor.
B737-800 First Officer reported Flight Attendant notification of 'burning wire' fumes in the passenger cabin. Captain executed an uneventful diversion after flight attendants in aft galley reported physiological symptoms.