E Letter

There are a variety of factors that need to be considered in relation to the vaccination of the older population. A gradual decline of the immune system occurs as people age (known as immunosenescence), impacting how the immune system responds to new infections, as well as the effectiveness of long-term immune memory. It is for this reason that some vaccines are specifically designed for the older population and aim to enhance the immune response by using higher immunogenicity formulations or by containing adjuvants. Providing optimal protection can also be complicated due to the increasing prevalence of multiple co-morbidities in the ageing population. Specific medical conditions or targeted therapies (eg. chronic renal conditions, chemotherapy for cancers etc) can also cause older adults to be more vulnerable to infections and their complications. Further to this, relying on patient recall, as well as a lack of awareness for the recommended vaccines for the older population, can result in either missed vaccines or additional unnecessary doses being administered.

There are multiple vaccines recommended for the older population as outlined below.

Herpes zoster (Shingles) vaccines

Shingles is caused by a reactivation of the varicella virus and will occur in approximately 20-30% of people in their lifetime. Older people (> 70 years of age) are more likely to suffer post-herpetic neuralgia (PHN) following a shingles infection than younger people. PHN is a chronic neuropathic pain which can affect 1 in 4 cases of shingles diagnosed in those > 80 years. It can persist for months to years with pain control being difficult to manage, impacting quality of life.

There are currently 2 vaccines available in Australia for the prevention of shingles:

• Zostavax®- a live-attenuated vaccine
• Shingrix®- an adjuvanted recombinant varicella zoster virus glycoprotein E (gE) subunit (non-live) vaccine

Zostavax®

Zostavax® has been shown to reduce the incidence of developing shingles by up to 50%, as well as the incidence of PHN in those ≥ 60 years of age by 66%. It is currently funded under the National Immunisation Program (NIP) for persons aged 70 years, with a catch-up program for those aged 71–79 years also funded (until October 2023). As it is a live-attenuated vaccine, it is contraindicated for use in those who are immunosuppressed, or on immunosuppressive medications (eg; Rituximab, Azathioprine, Prednisolone, chemotherapy etc). Prior to administering Zostavax® it is important to take a thorough patient history to determine suitability for immunisation.

Shingrix®

Shingrix® is preferred over Zostavax® for the prevention of shingles due to a higher efficacy, particularly in the older population. In those aged ≥ 50 years, Shingrix® provided 97% protection against shingles in immunocompetent individuals and 91% protection in those aged > 70 years. Clinical trials have demonstrated high efficacy up to 4 years following vaccination with immunogenicity data indicating this is likely to persist beyond 10 years.

Shingrix® is registered for use in adults aged ≥ 50 years. It is only available through private prescription and supplies are currently limited. It is a non-live vaccine and as such can safely be administered to immunocompromised individuals. ATAGI recommends a 7 day interval between the administration of COVID-19 vaccines and Shingrix®, and prefers that FluadQuad and Shingrix® are not co-administered on the same day.

Further guidance can be provided by reviewing the Australian Immunisation Handbook: Table. Live shingles vaccine (Zostavax) screening for contraindications or by contacting SAEFVIC prior to immunisation.

Pneumococcal vaccines

Invasive pneumococcal disease (IPD) can manifest as meningitis, pneumonia and bacteremia, with severe disease requiring hospitalisation, causing significant morbidity and even death. The elderly (along with infants) are at the highest risk of developing IPD. Recommendations for pneumococcal vaccines in adults vary according to age and medical condition [refer to ATAGI clinical advice on vaccination recommendations for people with risk conditions from 1 July 2020]. Pneumococcal vaccines are currently provided for free on the NIP for the following people:

• Aboriginal and Torres Strait Islander adults with NO risk condition – 1 dose of Prevenar 13® at 50 years of age, followed 8 weeks later by 2 doses of Pneumovax® 23, given 5 years apart
• Non-indigenous adults with NO risk condition – 1 dose of Prevenar 13® at >70 years
• Non-indigenous adolescents/adults diagnosed with a risk condition – 1 dose of Prevenar 13® at diagnosis, followed by 2 doses of Pneumovax® 23, given 5 years apart

In adults, injection site reactions may occur > 3 days following the Prevenar 13® dose given at > 70 years, particularly in those who have previously received Pneumovax®23. A history of large local injection site reactions following previous pneumococcal vaccines is not a contraindication to further doses.

Refer to MVEC: Pneumococcal for more information.

Influenza vaccines

For older adults, and those with certain medical conditions (eg. chronic lung disease, cardiac disease, immunosuppression), influenza disease can cause serious morbidity and mortality. Annual influenza vaccination is strongly encouraged and it is available for free on the NIP for those ≥ 65 years of age and/or adults with certain medical conditions. Due to a reduced immune response to routine influenza vaccines, those aged ≥ 65 years should receive higher-immunogenicity influenza vaccines.

Refer to MVEC: Influenza for specific information on brands and dosing.

COVID-19 vaccines

Older people and those with comorbidities (eg. hypertension, diabetes, chronic lung disease etc) are much more likely to suffer from severe COVID-19 disease if infected. Of those who are > 80 years of age and have COVID-19 disease, approximately 1 in 3 will die from it.

COVID-19 vaccination requires a 2-dose primary course for immunocompetent individuals, or a 3 -dose primary course for those with immunocompromise. A primary course shoulod be followed by a booster dose ≥ 3 months later, and a further “winter booster” dose ≥ 3 months after that for select individuals.

For more information on COVID-19 vaccination for older people please refer to COVID-19 vaccination – COVID-19 vaccination decision guide for frail older people, including those in residential aged care facilities.

Considerations for residents of residential aged care facilities (RACF)

Whilst every effort should be made to immunise residents of RACF at risk of vaccine preventable diseases like COVID-19 and influenza, it is important to monitor for adverse events following immunisation (AEFIs). Due to a high incidence of cognitive impairment, elderly residents may not have capacity to self-report any side effects. Any AEFIs experienced within 5 days of vaccination should be reported to SAEFVIC. It is important to monitor for non-specific symptoms seen in the elderly population when unwell such as falls, delirium, functional decline, decrease/loss of appetite or changes in mood/behaviour.

For further information on additional cares that may be required and management of symptoms following vaccination in residents of RACF refer to Guidance for vaccination care of residents of Victorian Residential Aged Care Facilities.

Reporting to the Australian Immunisation Register (AIR)

The AIR provides a record of all vaccine doses given, the date of administration as well as the specific brands used. Since 2016 vaccines administered to Australians of any age have been recorded onto the AIR. Patient recall, particularly in the older population, is not reliable and as such it important that immunisation records are accurately maintained and reviewed regularly.

From March 2021, new legislation came into effect making reporting vaccines to AIR mandatory. This includes all COVID-19 vaccines, influenza vaccines and all National Immunisation Program vaccines.

Resources

• Australian Government Department of Health: Immunisation for Seniors
• MVEC: Influenza
• MVEC: Zoster
• MVEC: Pneumococcal disease and vaccines
• MVEC: COVID-19 vaccines: Frequently asked questions
• MVEC: Australian Immunisation Register
• COVID-19 vaccination – COVID-19 vaccination decision guide for frail older people, including those in residential aged care facilities
• Guidance for vaccination care of residents of Victorian Residential Aged Care Facilities
• Aw D. Silva B. and Palmer D. Immunosenescence: emerging challenges for an ageing population Immunology 2007 Apr; 120(4): 435–446
• Gustafson C. Kim C. Weyand C. Goronzy J Influence of immune aging on vaccine responses Journal of Allergy and Clinical Immunology 2020 May; 145(5): 1309–1321

Background

Epilepsy is a disorder of the brain that leads to a person having seizures (disruptions to the electrical activity in the brain). Epilepsy can result from genetic conditions, brain injury or infection, hypoxic insult at birth, brain tumours or neurodegenerative diseases. However, the cause of epilepsy in most people is unknown. It can develop at any stage of life but is most commonly diagnosed in childhood, adolescence and in adults over 60 years of age. Approximately 250,000 Australians (or 1% of) are currently living with epilepsy.

Seizures of epilepsy can be controlled with anti-epileptic medication/s and by recognising and managing triggers. Common triggers include lack of sleep, stress, illness, hormonal fluctuations, drug and alcohol use, and photosensitivity. 

In general, vaccination is recommended for individuals with epilepsy. 

While, in rare instances, vaccines can trigger seizures, it is important to note that infections, including vaccine-preventable diseases (e.g., measles, influenza or COVID-19), can trigger seizures in individuals with epilepsy. Therefore, a risk/benefit assessment is important when planning vaccination. 

Any seizure that occurs within 14 days of receiving a vaccine are defined as vaccine-proximate seizures (VPS). Most types of epilepsy do not have a high risk of VPS. However, there are some genetic epilepsies with a strong association with VPS. These include Dravet syndrome and genetic epilepsy with febrile seizures plus (GEFS+). 

Dravet syndrome

Dravet syndrome is a rare and severe form of infantile onset epilepsy with a prevalence of 1 in 15,500 – 40,000 children. It is caused by a genetic mutation, usually a new/non inherited (de novo) change in the sodium channel gene (SCN1A). Children with Dravet syndrome classically present with prolonged febrile seizures in the first year of life. Seizures can be hemiclonic (one-sided) or generalised tonic-clonic. They can be sustained (lasting an extended period of time) such as in status epilepticus (SE). Following the first seizure, children with Dravet syndrome can develop refractory (uncontrolled) afebrile seizures, particularly myoclonic seizures, and a plateau or regression in their development. In approximately 30% of children with Dravet syndrome, the first seizure is vaccine-proximate (often occurring following the 4 or 6 month vaccines).  VPS occurring in infants, particularly if they are prolonged or classed as SE, should raise suspicion of Dravet syndrome.  

Immunisation can cause an earlier age of seizure onset in children with Dravet syndrome. However, there is no difference in developmental or seizure outcomes in children who had a first seizure proximate to immunisation compared to children whose first seizure was unrelated to immunisation. 

Genetic epilepsy with febrile seizures plus (GEFS+)

Genetic epilepsy with febrile seizures plus (GEFS+) describes a spectrum of seizure disorders of varying severity. A diagnosis of GEFS+ is usually made in individuals who are experiencing febrile seizures beyond the usual age range of up to 6 years and who have family members across different generations with a history of different types of epilepsy involving febrile seizures and/or recurrent afebrile seizures. 

Individuals with GEFS+ may experience VPS. 

Immunisation

Whilst vaccination is generally recommended in individuals with Dravet syndrome and other genetic epilepsies, there is a well-reported association with febrile seizures/SE following vaccination. Seizures most commonly occur within the first 48 hours following inactivated vaccines (e.g., influenza vaccines, COVID-19 vaccines, Infanrix hexa) and 5-10 days following live-attenuated vaccines (such as the measles-mumps-rubella, MMR, vaccine given at 12 months of age). 

Recommendations and management

Children with Dravet syndrome or GEFS+ and other children at risk of vaccine-proximate seizures should be referred to a specialist immunisation clinic for assessment prior to vaccination. 

Vaccination requires a comprehensive discussion between the patient’s family and the treating medical teams. Usually, expert advice from both immunisation specialists and neurologists is required and a clear plan is devised to ensure that vaccines can be administered under careful medical supervision (refer to protocol in resources). Vaccine administration for these groups includes admission for immunisation under observation and sometimes the prophylactic administration of paracetamol and benzodiazepines. Whilst there is no published data evaluating prophylactic measures to prevent seizures in children with Dravet syndrome undergoing immunisations, there is anecdotal evidence that this can reduce the rate of immunisation-related seizures and SE. 

Individuals with stable epilepsy, who have not had a previous VPS and whose type of epilepsy is not strongly associated with VPS, can generally be vaccinated safely in the community. However, where there are questions or concerns about the safety of vaccination in an individual, a referral to a specialist immunisation clinic could be considered. 

Resources

• RCH Kids health information: Epilepsy
• RCH Kids health information: Febrile seizures
• Epilepsy Action Australia: Seizure Types and Classification
• Symonds, J. et al Incidence and phenotypes of childhood-onset genetic epilepsies: a prospective population-based national cohort Brain: A journal of neurology 2019 August 142(8)2303-2318
• Protocol for immunisation in children with Dravet Syndrome and other children with vaccine-proximate seizures (RCH intranet access only)
• Protocol for immunisation of children with Dravet syndrome or other vaccine-proximate seizures
• Epilepsy Foundation: what causes epilepsy?

Background

Eczema, or atopic dermatitis, is a skin condition affecting many people of all ages but is most common in infants and young children. It affects approximately 40% of babies and children worldwide and often appears in the first year of life. Many children grow out of eczema around the age of 5 years however, there are some individuals who will have eczema throughout their life.

Eczema, along with asthma, allergy and allergic rhinitis are more formally known as atopic conditions. Of those children with moderate to severe eczema, a small number will go on to develop food allergy, asthma of childhood and/or allergic rhinitis.

It is not well understood why some individuals develop eczema or other atopic conditions however, there is research and clinical trials currently underway looking into possible genetic, immunological and environmental causes for eczema.

Vaccines

It is safe and recommended for individuals with eczema to receive vaccines according to the National Immunisation Program (NIP); and there is currently no robust evidence suggesting a causal link between immunisation and eczema. Eczema affects people differently and there are multiple triggers that may cause flares including viral or bacterial infections, environmental allergens, stress and some medications.

Recommendations

Eczema may flare in the days following immunisation, however this is not a contraindication to future vaccines.  It is recommended to follow an eczema treatment plan which may include regular moisturiser, topical steroids and barrier creams. If the first presentation of eczema following immunisation, it is recommended to seek GP assessment for an appropriate management plan.

Precautions

If there is active eczema at the intended site of injection, an alternate site could be considered to reduce the risk of infection (or abscess). If no other site is deemed suitable, cleaning the site with an alcohol-based wash/single use alcohol swab and allowing the site to dry completely before injecting could be considered.

BCG vaccination should be deferred if there is active eczema at the injection site.

The smallpox vaccine ACAM2000™ is contraindicated in individuals with active eczema, atopic dermatitis or other exfoliative skin conditions due to the risk of developing eczema vaccinatum (a reaction to smallpox vaccination experienced by people with eczema/atopic dermatitis resulting in a severe rash and systemic illness).

Resources

• Australasian Society of Clinical Immunology and Allergy: Eczema (Atopic dermatitis)
• Olesen A, Juul S, Thestrup-Pedersen K, Atopic dermatitis is increased following vaccination for measles, mumps and rubella or measles infection. ActaDV 2003;83(6):445-50
• DermNet NZ: Atopic dermatitis
• Australian Immunisation Handbook: Tuberculosis
• Australian Immunisation Handbook:Preparing for vaccination
• MVEC: Mpox (monkeypox)
• RCH Kids Health Info: Eczema