Contents

3 Vaccination questions and concerns

3.1 Some commonly asked questions

3.1.1 Vaccine scheduling

Which vaccines can be administered at the same visit?

There are no known contraindications to administering registered vaccines at the same visit, provided they are administered in separate syringes at separate sites. If two or more parenterally or intranasally administered live vaccines are not given at the same visit, then a minimum interval of four weeks is recommended. The rationale is based on limited data where varicella vaccine has been given within four weeks of measles-containing vaccine and breakthrough varicella disease (chickenpox) has occurred. Any time interval is acceptable between administering live oral vaccines and parenteral vaccines (eg, rotavirus and BCG vaccines), live and inactive vaccines, or two inactive vaccines.

What steps are required if the Schedule is interrupted?

Generally there is no need to repeat prior doses; simply continue the Schedule as if no interruption has occurred (see Appendix 2). Special circumstances where the above does not apply are as follows:

Remember that children who miss one vaccine dose may do so again, and that close follow-up may be required.

How should the rest of the Schedule be handled when an adverse event has occurred following immunisation?

Proceeding with the Schedule after an adverse event following immunisation (AEFI) depends on the nature of the event and the likelihood that it was caused by the vaccine. Most prior adverse events are not contraindications to receiving further immunisations. The only absolute contraindication to receiving a vaccine is an anaphylactic reaction to a prior dose or an ingredient in the vaccine. However, immune dysfunction can be a contraindication to receiving live vaccines (see section 4.3).

Adverse events should be reported to CARM, PO Box 913, Dunedin, using the prepaid postcard HP3442, or via online reporting (https://nzphvc.otago.ac.nz/reporting) (see section 2.5: ‘AEFI reporting process – notifying CARM’).

Consult the AEFI section in each of the Handbook chapters, and seek specialist advice (eg, from the medical officer of health, the Ministry of Health, or the Immunisation Advisory Centre, if required). Other vaccines not related to the AEFI can usually be administered as per the Schedule.

3.1.2 Babies and childrenTop

What if the baby had a difficult birth or was premature?

Low birthweight and prematurity are not contraindications to vaccination. The recommended Schedule immunisations should be carried out at the appropriate chronological age. However, if the baby is still in hospital or recently discharged, please seek the advice of the treating specialist (see also section 4.2 on special risk groups and section 8.5 on hepatitis B). These babies may be at higher risk of some of these diseases, so vaccinating them on time is important. For rotavirus vaccine, it is best to vaccinate preterm infants as they leave hospital because of vaccine virus shedding in the stool. However, if discharge is not anticipated before age 15 weeks, which is the upper age limit for giving dose one, then giving rotavirus vaccine in hospital is acceptable (see sections 4.2.1 and 17.5.3).

What special vaccines are offered to newborn babies?

Babies born to HBsAg-positive mothers should receive:

If HBIG and/or hepatitis B vaccine is inadvertently omitted, administer as soon as the omission is recognised. HBIG can be administered up to seven days post-delivery. If there is a delay for longer than seven days, seek specialist advice. These babies should then continue as per the Schedule at ages 6 weeks, 3 months and 5 months. Serological testing is required at 9 months of age (see section 8.5.3).

A baby at higher risk of tuberculosis is offered a Bacillus Calmette-Guérin (BCG) immunisation soon after birth (see section 20.5 for neonatal BCG eligibility and the timing of neonatal BCG). The lead maternity carer will discuss the need for the vaccine with the mother prior to her baby’s birth, and the BCG immunisation may be given while the baby is in hospital, or later at a community clinic.

What are the special requirements of immigrant children?

Immigrant children should be immunised according to the New Zealand Schedule with due account taken of documented prior vaccine administration and the eligibility criteria defined in the Health and Disability Services Eligibility Direction 2011, available on the Ministry of Health website (www.health.govt.nz/eligibility) (see also section 4.4).

It is important to err on the side of giving rather than withholding vaccines if the vaccination history is uncertain (see Appendix 2). The immunisation status of all immigrant children should be checked when they register with a primary health care provider.

Is it possible to boost a child’s immune system by other means?

Children who are healthy have an immune system that functions optimally. Eating a healthy diet, getting adequate sleep and exercise, and minimising stress will help keep the immune system healthy. However, none of the above confer the disease-specific immunity that vaccination provides (see also section 3.3.4).

3.1.3 Allergies and illnessesTop

What if the child is unwell on the day of immunisation?

Minor illness or being in the recovery phase of an illness is not a reason to postpone immunisation. Babies and children with a significant acute illness and a temperature >38oC should have immunisation postponed until they are better. This is not because they are at particular risk of vaccine reactions, but because complications of the acute illness may be misinterpreted as a complication of the immunisation, or an AEFI may complicate the clinical picture of the acute illness. (See section 1.4 on general contraindications to vaccination, and the contraindications sections in the disease chapters.) If immunisation is postponed, it is important to ensure the child is placed on the recall for the immunisation at a later date.

What if the child is due to have an operation (elective surgery)?

There is no evidence that anaesthetic impairs the immune response to a vaccine or increases the risk of AEFI.

Vaccination with inactive vaccines is preferably avoided for 48 hours prior to an anaesthetic in case post-vaccination symptoms such as fever interfere with preparation for surgery. There is no reason to delay surgery following vaccination with a live vaccine if the child is well at the time of immediate pre-operative assessment. There is no reason to delay vaccination after surgery, once the child is well and has recovered from the procedure. See the Association of Paediatric Anaesthetists of Great Britain and Ireland Immunisation guidelines (www.apagbi.org.uk/publications/apa-guidelines).

Ideally, individuals scheduled for splenectomy should be immunised at least two weeks before the operation. Pneumococcal, meningococcal, Hib, influenza and varicella vaccines are recommended for these individuals pre- or post-splenectomy (see section 4.3.4 and the relevant disease chapters). Note: if the surgery is an emergency, then the immunisation programme should commence two weeks later.

What if the child has a chronic disease?

Children with chronic diseases should be immunised in the normal way, especially as they may be more at risk from the severe effects of vaccine-preventable diseases. However, if the illness or its treatment results in impaired immunity, immunisation with live vaccines should be considered carefully (see sections 4.2 and 4.3), and the child’s GP or paediatrician should be consulted before immunisation.

What if the child has had seizures?

A diagnosed neurological condition is not a contraindication to any vaccine on the Schedule. However, an evolving neurological condition (eg, uncontrolled epilepsy or a deteriorating neurological state) is still considered a contraindication to pertussis immunisation. Until the neurological condition has been diagnosed or stabilised, there is a risk that changes may be attributed to the vaccine. A family history of seizures or epilepsy of any type is not a contraindication to immunisation.

A febrile reaction may occur after any vaccine and result in a febrile seizure in a susceptible child. Vaccine-related febrile seizures are rare, although the risk is higher following administration of certain vaccines, such as influenza (section 10.7), MMR and MMRV (see section 21.7) vaccines. These seizures, although frightening for a parent, are almost always benign, with no associated sequelae.

What if the child is allergic?

Only anaphylaxis to a prior dose of vaccine, or to an ingredient in the vaccine, is considered an absolute contraindication. See the contraindications and precautions section in each disease chapter, in particular, pertussis (section 14.6), measles (section 11.6) and influenza (section 10.6) and rotavirus (section 17.6). Children with asthma, eczema, hay fever and other allergies should be immunised in the usual way. Studies have shown that immunised children have slightly lower rates of atopic diseases.

Can children be immunised if they are known to develop a rash with antibiotics?

Yes. The only concern is if a child has had a previous anaphylactic reaction (a rash alone is not anaphylaxis) to a component of a vaccine. Check the vaccine data sheet for the list of components.

Can all children receive all the vaccines?

A child cannot receive a vaccine if they have had an anaphylactic reaction to any component of the vaccine. A child may have an underlying condition that is a contraindication to some vaccines. Most importantly, children with illnesses or treatment that causes immunosuppression should not receive live attenuated vaccines (see sections 4.2 and 4.3 for special risk groups, chapters 11, 13 and 18 for MMR and chapter 21 for varicella).

3.1.4 Parents, guardians and contactsTop

What if the child’s mother or guardian is pregnant or breastfeeding?

This is not a contraindication to giving any of the Schedule vaccines to a child, including live vaccines, such as the measles, mumps and rubella (MMR) vaccine. In addition, consideration should be given to the risks for the mother or guardian and baby from diseases such as pertussis, which can be life threatening in infants.

Pregnancy is an important opportunity to ensure the infant’s siblings have received age-appropriate immunisation. Pertussis (as Tdap) and influenza vaccines are recommended and funded for pregnant women (see section 4.1).

Are live virus vaccines such as measles, mumps, rubella and varicella transmissible?

These are highly attenuated (weakened) viruses designed specifically to induce an immune response without causing disease. There have been no recorded cases of measles, mumps or rubella disease in a contact of a vaccinee. Internationally, there have been only 10 documented cases of attenuated varicella vaccine virus causing disease in contacts, particularly immune-compromised contacts (see chapters 11, 13 and 18 for MMR and chapter 21 for varicella).