New approaches to safety surveillance of seasonal trivalent influenza vaccine in pregnant women: Experiences from FASTMum 2013
Regan, A., Blyth, C., Taksdal, S., Mak, D., Richmond, P., & Effler, P. (2013). New approaches to safety surveillance of seasonal trivalent influenza vaccine in pregnant women: Experiences from FASTMum 2013. Options for the Control of Influenza VIII.
Pregnant women are at increased risk of morbidity and mortality due to serious influenza related complications. Antenatal vaccinations with seasonal trivalent influenza vaccine (TIV) can reduce morbidity among pregnant women, and the available data suggest a protective effect among infants born to vaccinated mothers. For these reasons, in 2012, the World Health Organisation’s Strategic Advisory Group of Experts on Immunization stated that pregnant women are the highest priority for seasonal influenza vaccination. Influenza vaccination coverage rates among pregnant women remain low in a number of countries. One of the reasons for this low coverage may be related to pregnant women’s perceptions of influenza vaccination. Although the safety of influenza vaccination administration during pregnancy has been well established, half of antenatal patients who refuse vaccination cite safety concerns as their primary reason. Ongoing and timely safety surveillance could help reassure pregnant women and promote vaccine uptake. In 2013, the Western Australia Department of Health modified its TIV safety monitoring system FASTMum (Follow-up and Active Surveillance of TIV in Mums) to collect information regarding the safety of TIV in pregnant women using SMS technology. Materials and Methods: In Western Australia, seasonal antenatal influenza vaccinations are reported to the Western Australia Department of Health by vaccination providers. In 2013, SMS technology was introduced as a semi-automated, rapid method to capture adverse events following immunization in a timely manner. Of the 2203 antenatal vaccination reports received between 01 March and 15 May 2013, 1852 (84.1%) of these women consented to SMS follow-up and provided a mobile telephone number. One week post vaccination, the Western Australia Department of Health sent a SMS message to these women asking if they had experienced any reactions following the 2013 TIV. Women who responded “yes” to this message were followed-up with a telephone questionnaire.
On average, complete information regarding adverse events following TIV was obtained within one month (28 days) of vaccine administration. Of the 1425 women who responded to SMS in the first two months of influenza season, one in ten (10.8%) pregnant women reported a non-serious adverse event one week following receipt of the 2013 TIV. Of these women, 52 (3.6%) reported a local reaction at the site of injection, 29 (2.0%) reported fatigue, 28 (2.0%) reported fever, 27 (1.9%) reported respiratory symptoms (eg, coughing, congestion, sneezing), and 24 (1.7%) reported headache. Of the 427 women who did not respond to SMS, 333 (88.0%) were followed-up with a telephone interview. With the exception of injection-site reaction, the rate of adverse events was consistent with that of women who responded to SMS. No serious reactions related to the influenza vaccine were identified.
The results from FASTMum 2013 are promising and provide timely evidence of 2013 TIV safety in pregnant women in the early months of influenza vaccination season in the southern hemisphere. These results demonstrate the feasibility of using mobile phone technology to monitor vaccine safety in near real-time. Information resulting from this surveillance effort is important for addressing lingering concerns among providers and antenatal patients about the safety of influenza vaccine for pregnant women.
influzena, vaccination, pregnant women, seasonal trivalent influenza vaccine (TIV)