The Australian Immunisation Handbook 10th Edition 2013

All adults aged ≥65 years
There is evidence that influenza vaccine reduces hospitalisations from influenza
and pneumonia and all-cause mortality in adults ≥65 years of age. 30 (See also
4.7.4 Vaccines above.)
Persons at increased risk of complications from influenza infection
Persons aged ≥6 months with conditions predisposing to severe influenza, 7
such as:
• Pregnancy – Pregnant women (and women planning pregnancy) are
recommended to be immunised against influenza because they are at
increased risk of morbidity and mortality from influenza and because
there is good evidence that influenza immunisation in pregnancy is safe
and effective. 38-45 The risk to the mother of complications from influenza
increases in the later stages of pregnancy. 38-42,46-50 There is also a growing
body of evidence showing that influenza vaccination of pregnant women
protects infants against influenza for the first 6 months after birth. 39,51,52 Most
evidence around infant protection is from studies of maternal influenza
vaccination in the second or third trimester. 38-42,46-51 Influenza vaccination is
thought to provide protection for up to a year, but there is limited evidence
that immunity may start to wane from 4 months following immunisation.
Although it is recommended that all pregnant women should be immunised
as early as possible in pregnancy, 53 the precise timing of vaccination will
depend on the time of the year, vaccine availability, influenza seasonality,
gestation of pregnancy and the likely duration of immunity. (See also 4.7.8
Pregnancy and breastfeeding below.)
• Cardiac disease, including cyanotic congenital heart disease, coronary artery
disease and congestive heart failure – Influenza causes increased morbidity
and mortality in children with congenital heart disease and adults with
coronary artery disease and congestive heart failure. 37,54-57
• Down syndrome – Persons with Down syndrome should receive annual
seasonal influenza vaccine whether or not they have congenital heart
disease. This is due to the presence of anatomical abnormalities, which put
them at increased risk of upper respiratory tract infections, as well as a high
prevalence of other medical conditions that put them at increased risk of
severe influenza. 56
• Obesity – Persons with significant obesity, defined as a BMI ≥30 kg/m2 , with
or without other underlying conditions, have been identified as being at
increased risk for hospitalisation with respiratory complications following
influenza. 37 This risk was particularly apparent during the 2009–2010
pandemic. 58,59
252 The Australian Immunisation Handbook 10th edition