On 10/2/2012, he reported being in good health with receipt of first AVA (Bioport - FAV308) vaccination and annual Influenza (SP-UH713AB) intramuscular vaccination. He recalls his right arm "hurt like hell" for 3 days following AVA vaccine, and his right arm remained sore stating it felt as if "his arm had been hit by a hammer & it hurt to lift". He reported no other symptoms and his arm pain resolved within 1 week. On 10/10/2012 (day 8) he took a 17 hour flight. On 10/11/2012 (day 9) he complained of feeling poorly being tired & weak with a subjective fever, low energy, mild sinus congestion & post nasal drip. He described his symptoms as "if coming down with a cold" & he felt a little better after some sleep. On 10/12/12 he went to medical for a persistent painful small fluid filled lesion to left scalp: a 3x2cm small raised lesion behind left ear in hairline. It was lanced, had a negative KOH culture & was diagnosed with folliculitis & given topical BACTROBAN. On 10/14/2012 lesion was "dry healed rash with alopecia" (per provider) & he was cleared to fly. On 10/19/2012 he flew at 6-7 thousand feet with no reported concerns. On 10/22/2012 (day 20 after vaccinations and 4 days after flying) he reported his first 30 minute "headache" while working on a computer. HA described as a sharp shooting pain from bridge of nose that extended down to left inner canthus extending across his cheek-eye socket to temple region & then down to left ear & neck. He describes this 8-9/10 pain as "if pliers were gripping the nerve pinching causing a severe headache". He also stated mucosal lining in left nostril burned. He denied any visual disturbance or tearing, no foreign body or trauma to eyes/head. He did not wear/need eyeglasses, was not in sunlight, not precipitated by alcohol, & was not exposed to any odors or chemicals. He did have to squint due to the pain. He reported this pain returned spontaneously 3 more times regardless of activity between 0900-1200 hours lasting about 30 minutes each on 10/24, 10/27, and 10/28. Each episode he "could feel area tighten up and then his head hurt" and then would feel exhausted for 2-3 hours upon resolution of headache. He took MOTRIN but was unsure if medication helped or if headache resolved on own. He sought treatment after episode #4 on 10/29/12 stating he "never felt pain like this before" describing a daily "headache like pressure (see above description). Provider documented "headache extending thru medial orbit and cheek, and was accompanied by ipsilateral watery nasal discharge, eye tearing, facial sweating and eyelid swelling. Headaches were very specific in timing and location". His CT head, CRP, ESR, vitals (BP) and neuro/physical exam were normal. He was diagnosed with headache syndrome and treated with ZANTAC, prednisone taper (60mg x 5 day, then 50-40-30-20 mg 1 day each) and given prescription for nasal IMITREX (headaches did improve with steroids slightly). While his differential did include evaluation for air sickness-altitude injury, temporal arteritis, migraine or allergies (on FLONASE and ALLEGRA); provider advised "demographics are more consistent with cluster headaches". His "headache" symptoms initially were ipsilateral but were bilateral in December 2012. He advised of daily stabbing in the peri and retro-orbital region and upper maxillary and lower frontal sinus areas occurring 10-15 times a day with burning sensation at the bridge of his nose (not like initial 4 headaches-less intense). He feels pains shortly after awakening and has no problems sleeping (7-9 hr/night). He complains of intermittent pains to other body parts which migrate from one spot to another day by day ultimately returning to original spot (bilateral low back, left groin, suprapubic area, and forearms). He reports some muscle spasms to inner quads that occur when he has testicular/groin pain. He has generalized malaise and "just feels bad". His HA is worse with exercise.