SERIOUSNESS CRITERIA OTHER: IMPORTANT MEDICAL EVENT. Initial unsolicited report received from the literature on 30-Oct-2017. This case is linked with case 2017SA212703 (same reporter). Background. Some studies have found a higher frequency of fever with trivalent live attenuated influenza vaccine (LAIV) than with inactivated influenza vaccine (IIV), but quadrivalent LAIV has not been assessed. Understanding fever is important for safety reviews and for parents and providers. In addition, there have been only a limited number of studies in which text messaging was used for vaccine adverse-event (AE) surveillance. Methods. We conducted a prospective observational study in 3 community clinics to assess post-influenza vaccination fever in 24- to 59-month-olds during the 2013-2014 season. Enrolled families of children who received quadrivalent LAIV (LAIV4) or IIV (trivalent IIV3 or quadrivalent IIV4) replied to text messages that assessed their temperature on vaccination night and the next 10 nights (days 0 to 10); missing data were collected via telephone and a diary. We compared frequencies of fever (temperature 100.4 degree F) according to vaccine group on days 0 to 2 and 3 to 10 by using ?2 and multivariate log-binomial regression adjusted for age, previous influenza vaccination, and vaccine coadministration. We also assessed outcomes using all sources versus only text messages. Results. Most (84.1% [n = 540]) eligible parents enrolled. Fever frequencies on days 0 to 2 did not differ between LAIV4 and any IIV (3.8% vs 5.7%, respectively; adjusted relative risk [aRR] [95% confidence interval], 0.60 [0.25-1.46]), between LAIV4 and IIV4 (4.2% vs 7.1%, respectively; aRR, 0.58 [0.19-1.72]), or between IIV4 and IIV3 (7.1% vs 6.0%, respectively; aRR, 1.02 [0.30-3.46]). The findings were similar when all data sources versus text-message data alone were used. There were no significant differences on days 3 to 10. Conclusions: Post vaccination fever frequencies were low overall and did not differ according to influenza vaccine type during the 2013-2014 influenza seasons. The similarity of results when data were limited to text messages lends support to its use for surveillance of vaccine adverse events. Keywords. fever; influenza; live attenuated; text message; vaccine safety; vaccination. This case involves a child patient (age between 37 months to 59 months, gender not reported), who was vaccinated with a dose of a dose of INFLUENZA VACCINE (IIV3) and HEPATITIS A VACCINE (manufacturer- other) (batch number, expiry date, dose, route were not reported for both the vaccines) on an unknown date (in between September 2013 and April 2014). Patient's medical history and concomitant medication was not reported. On an unknown date, in between day 3 to day 10 post vaccination, patient had fever (temperature greater than or equal to 102.2 degree F). On an unknown date, following the vaccination, patient also developed gastroenteritis due to which the patient had a day eight pediatric visit. Patient's other laboratory and corrective treatment was not reported. Outcome for both the events were not reported. Upon internal review the case was considered as serious because of important medical event: gastroenteritis. Documents held by sender: none. Sender's Comments: In this case patient experienced gastroenteritis and fever after vaccination with INFLUENZA VACCINE. Time to onset is compatible with the role of vaccine. However, further information on medical history including birth history, immune status at the time of vaccination, previous vaccination and tolerance, laboratory investigations excluding alternative etiologies would be needed to fully assess this case. Moreover, as two vaccines were administered concomitantly, the role of each component cannot be assessed separately.