Published: 1 March 2018

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Spontaneous Reports: Seasonal Influenza Vaccination 2017

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Prescriber Update 39(1): 12-13
March 2018

Influenza has a significant impact on public health in New Zealand. The rate of influenza-associated hospitalisations for all causes and all ages in New Zealand has been estimated as 62.4 per 100,000 (1). The age groups with the highest rates were those 80 years of age and older (327.8 per 100,000) and children under one year (244.5 per 100,000)¹.

In addition, seasonal influenza in New Zealand has been estimated to be associated with all- cause medical deaths at a rate of 10.6 per 100,000 persons per year with the majority of deaths occurring in those 65 years and over².

During 2017, there was a total of 335 Intensive Care Unit cases of influenza-like illness of which 27 of the 352 collected specimens tested positive for influenza viruses³.

In 2017, the Centre for Adverse Reactions Monitoring (CARM) received 191 reports of adverse reactions to seasonal influenza vaccines (Table 1). There were 467 suspected adverse reactions described in these 191 reports.

Table 1: Number of reports of adverse events following influenza vaccination received by CARM and number of influenza vaccine doses distributed, 2013–2017

	2013	2014	2015	2016	2017
Reports of adverse event reports following influenza vaccination	290	253	241	212	191
Influenza vaccine doses distributed*	1,253,600	1,206,573	1,211,152	1,245,934	1,217,494
Estimated reporting rate per 100,000 doses	23.1	21.0	19.9	17.0	15.7

*The number of doses distributed is not equal to number of people to whom the vaccine was administered

The majority of these reports were submitted by nurses (74.9%). The most commonly reported reactions were injection site inflammation, arm pain, headache, fever and vasovagal reaction (Table 2).

Table 2: Top five reported suspected adverse reactions to the 2017 seasonal influenza vaccines

Adverse reaction	Number of events	Percentage of total events	Percentage of totalport
Injection site inflammation	46	9.9%	24.1%
Arm pain	29	6.2%	15.%
Headache	20	4.3%	10.5%
Fever	13	2.8%	6.8%
Vasovagal reaction	13	2.8%	6.8%

There were 10 reports that were classified as serious. Of these 10 reports, seven reports involved hospitalisation (3.7% of reports) and three reports were classified as life-threatening (severe allergic reactions) (1.6%).

In 2018, the funded influenza vaccine will be quadrivalent rather than trivalent. Please continue to report any suspected adverse reaction(s) to vaccines to CARM.

References

1. Khieu TQ, Pierse N, Telfar-Barnard LF, et al. 2015. Estimating the contribution of influenza to hospitalisations in New Zealand from 1994 to 2008. Vaccine 33: 4087–92.
2. Kessaram T, Stanley J, Baker MG. 2015. Estimating influenza-associated mortality in New Zealand from 1990 to 2008. Influenza and Other Respiratory Viruses 9: 14–9.
3. ESR. 2017. Community and Hospital Surveillance: ILI, SARI ICU, Influenza and Respiratory Pathogens, 2017 Influenza Season, December 2017 17 January 2018. URL: https://surv.esr.cri.nz/virology/influenza_surveillance_summary.php (accessed 31 January 2018).