Contents

10 Influenza

10.5 Recommended immunisation schedule

Influenza vaccine should be given annually because protective antibody levels wane with time and the prevailing strains may change between years and may not have been included in the previous year’s vaccine. See Table 10.3 for a summary of the funded and unfunded recommendations for influenza immunisation.

10.5.1 Funded influenza immunisation

Funded influenza immunisation is available for the following groups. To encourage early uptake of the vaccine, funded immunisation is usually only available until the end of July each year.

At-risk adults

Adults aged 65 years and older

In adults aged 65 years and older, influenza vaccine has been shown to be effective against non-fatal and fatal influenza complications, influenza-like illness and laboratory-confirmed influenza (see Table 10.1).

Adults with underlying medical conditions

Influenza has been associated with increased morbidity and mortality in adults with underlying medical conditions.

Pregnancy and breastfeeding

Influenza vaccine is safe to administer during any stage of pregnancy or while breastfeeding. Pregnant women are at greater risk from complications associated with influenza illness. Pregnant women with co-existing medical conditions are at even greater risk of severe influenza-related morbidity. When pregnancy is superimposed on high-risk conditions such as asthma or diabetes, influenza-related morbidity is three to four times greater than in non-pregnant women with similar high-risk conditions.

There is no evidence that influenza vaccine prepared from inactivated virus causes damage to the fetus. The seasonal influenza vaccine is strongly recommended, and funded, for women who will be pregnant during the influenza season, usually May to September. The seasonal influenza vaccine is normally given in the second and third trimesters but should be offered to women who are or will be in the first trimester when influenza is expected to be circulating.

Because there is no registered vaccine for children aged under 6 months, vaccination during maternal pregnancy is highly recommended to improve maternal fetal passive antibody transfer. Influenza vaccination of pregnant women has been shown to significantly decrease influenza in their newborn babies.16, 25, 26, 47 Breastfeeding is also strongly recommended, to deliver passive immunity to the infant.16

Children

Influenza vaccine is funded for children with chronic illnesses and a history of respiratory disease. Children with the following conditions should be prioritised to receive influenza vaccine due to their increased risk:

Special considerations apply to children, as follows.

10.5.2 Recommended but not fundedTop

Influenza vaccine is recommended, but not funded, for the groups listed in Table 10.3.

Healthy adults

Healthy individuals are encouraged to have the vaccine, especially if they are in close contact with individuals at high risk of complications. Employers are encouraged to provide influenza vaccine to avoid illness in their employees, especially those engaged in health care and other essential community services. Immunising healthy individuals has been shown to be cost effective.

In order to optimise the protection of high-risk (see Table 10.3) infants and toddlers (including those aged under 6 months) all household and close contacts should receive influenza vaccine (not funded unless eligibility criteria are met).

Health care workers

The Ministry of Health strongly recommends, and expects, that all health care workers will receive annual influenza vaccination for their own protection and the protection of those in their care.

Table 10.3: Influenza vaccine recommendations

Note: Funded conditions are in the shaded rows. See the Pharmaceutical Schedule (www.pharmac.govt.nz) for the number of funded doses and any changes to the funding decisions.

Recommended and funded
All individuals aged 65 years and older.
Individuals aged 6 months to 64 years who:
  • have cardiovascular disease (ischaemic heart disease, congestive heart failure, rheumatic heart disease, congenital heart disease or cerebrovascular disease)
  • have chronic respiratory disease (asthma if on regular preventive therapy; other chronic respiratory disease with impaired lung function)
  • have diabetes
  • have chronic renal disease
  • have any cancer, excluding basal and squamous skin cancers if not invasive
  • have other conditions (autoimmune disease, immunosuppression or immune deficiency, HIV infection, transplant recipients, neuromuscular and central nervous system diseases/disorders, haemaglobinopathies, children on long-term aspirin, have a cochlear implant, errors of metabolism at risk of major metabolic decompensation, pre- or post-splenectomy, Down syndrome)
  • are pregnant
  • ​are children aged under 5 years who have been hospitalised for respiratory illness or have a history of significant respiratory illness.
Recommended but not funded
Individuals with asthma not requiring regular preventive therapy
Individuals with functional asplenia
Asplenic and immune-deficient individuals
Individuals in essential positions and health care workers
Individuals who may transmit influenza to persons at increased risk of complications from influenza infection
Travellers
Children aged under 5 years
Residents of residential care facilities
The homeless

Travellers

People travelling outside New Zealand, especially those who are in the at-risk groups who have not received vaccine during the previous autumn, are recommended to have influenza vaccination depending on the season and their destination. In tropical countries, influenza activity can occur throughout the year but is more likely during the monsoon, while in the northern hemisphere activity is commonest between the months of December and March. Outbreaks of influenza among organised tourist groups (eg, on cruise ships) can occur throughout the year.