Initial unsolicited report received from the literature on 29-Jul-2016. This case is linked to cases 2016SA140361, 2016SA140962, 2016SA140455, 2016SA140480, 2016SA140494, 2016SA140516, 2016SA140980, 2016SA140990, 2016SA141005, 2016SA141097, 2016SA141105 (same literature). Background: No comparative review of Vaccine Adverse Event Reporting System (VAERS) submissions following pandemic influenza A (H1N1) 2009 and seasonal influenza vaccinations during the pandemic season among one population has been published. Methods: We compared two populations' adverse event reporting rates. Adverse events (AEs) following vaccination were identified from VAERS for adults aged 17-44 years after pandemic (monovalent influenza [MIV], and seasonal (trivalent inactivated influenza [IIV3], live attenuated influenza [LAIV3]) vaccines. The first population vaccination coverage was provided by the Medical Surveillance System. The second population vaccination coverage was estimated using data from the National 2009 H1N1 Flu Survey and the Behavioral Risk Factor Surveillance System survey. Results: Vaccination coverage was more than four times higher for MIV and more than twenty times higher for LAIV3 in the first population than in the second population. The reporting rate of serious AE reports following MIV in the first population (1.19 per 100,000) was about half that reported by the second population (2.45 per 100,000). Conversely, the rate of serious AE reports following LAIV3 among the first population(1.32 per 100,000) was more than twice that of the second population. Although fewer AEs following MIV in the first population were reported overall, the rate of Guillain-Barre Syndrome (GBS) (4.01 per million) was four times greater than that in the second population. (1.04 per million). Conclusions: Despite higher vaccination coverage in the first population, the rate of serious AEs following MIV was about half that in the second population. The rate of GBS reported following MIV was higher in the first population. This case involves a 35-year-old male patient who was vaccinated with a dose of Monovalent H1N1 Vaccine (batch number, expiry date, route and site of administration not reported) on an unspecified date. Patient's ongoing history included Herpes Zoster on left side of back The patient's medical history included Back injury. Concomitant medications were not reported. On an unspecified date, 36 days following the vaccination, the patient developed Atypical GBS" (2)/Guillain-Barre syndrome and experienced ascending numbness, unable to walk and 'weakness all limbs'. Relevant laboratory tests included CSF examination which was remarkable for positive albumin cytologic dissociation and EMG which showed absent P waves in early Guillain Barre Syndrome (GBS). Other testes included CBC, CMP, CRP, ANA, MRI (head), tests involving cervical and thoracic spine. Corrective treatment included plasmapheresis intubated in ICU. It was further reported that the patient suffered relapse on discharge and was re admitted. There was a repeat plasmapheresis followed by course of IVIG with marked positive clinical response. The outcome of events were not reported. Upon medical review, the case was considered as serious due to important medical event: Atypical GBS" (2)/Guillain-Barre syndrome. Documents held by sender: none. Sender's Comments: Patient had Guillain-Barre syndrome 36 days following MONOVALENT INFLUENZA A (H1N1) 2009 VACCINE. Time to onset is compatible with the vaccine but too long, Guillain-Barre syndrome is usually preceded by upper respiratory tract or gastrointestinal tract infection, influenza infection and vaccination, in this case patient had herpes zoster left side of back a viral infection 4 weeks prior which could be triggering factor and also patient was vaccinated with influenza vaccine which is also one of the triggering factors, patient is also positive for albuminocytologic dissociation in CSF. Detail medical history, past vaccination history and its tolerance are needed to further assess the case. Based on the available information the role of vaccine cannot be excluded.