Time to protect vulnerable from influenza return

UNDERSTANDABLY, the medical spotlight is on the rollout of COVID-19 vaccines around Australia and the world. But as we step cautiously towards our first winter in the new “COVID-19 normal”, it  is vital to protect our patients from common infectious diseases that would usually be front and centre in the immunisation conversation.

Now is the time to talk to our patients about protection against serious cases of influenza and pneumococcal disease.

Winter can be a dangerous time for people in high risk categories, including those living with chronic lung disease and those aged over 70 years, who are more susceptible to severe cases of influenza and pneumococcal disease and at increased risk of hospitalisation. Amid anxiety about supply and possible (rare) side effects of coronavirus vaccines, and some confusion about the process, patients are telling us, at the Lung Foundation Australia, how eager they are to receive all necessary and available immunisations, not just those for COVID-19. While our patients are waiting for the COVID-19 vaccine, discussing and scheduling their shots for influenza and, where appropriate, pneumococcal disease can provide vital and timely protection.

We enter this winter in uncharted waters. Official figures show there is a real danger of complacency and loss of focus on influenza amid the ongoing COVID-19 storm. In 2020, Australia (and countries around the world) effectively skipped the influenza season. The Department of Health’s 2020 influenza  summary reports that, from mid-March, notifications of confirmed influenza cases fell dramatically. There were just 21 266 cases reported nationally and 37 deaths, compared with a staggering 309 798 cases for the 2019 season (a figure seven times greater than Australia’s previous 18-year average).

However, the Department of Health rightly urges caution when comparing 2020 with previous seasons, as the onset of the COVID-19 pandemic played a key role in reducing the spread of influenza. Physical distancing, community adherence to health messages and dramatic changes to both hygiene practices (hand washing, cleaning, mask wearing) and health-seeking behaviour limited the capacity for the influenza virus to spread. We cannot afford complacency as we return to “normal” behaviour, such as group gatherings, social events and general day-to-day contact with others.

In temperate climates such as ours, influenza infections usually peak around July–August and seasonal infections tend to be over by October, except in the Top End, which sees more year-round activity. So now is the time to discuss vaccination.

In a podcast for the Doherty Institute, Professor Kanta Subbarao, director of the WHO Collaborating Centre for Reference and Research on Influenza, explains that influenza generally lands in Australia from the Northern Hemisphere. With no prospect of international borders opening soon, it would seem infections may stay low. However, this could be a dangerous assumption because if influenza does re-emerge, unvaccinated people will be at increased risk. While we are yet to see a re-emergence of influenza globally, Professor Subbarao identifies some notable, if smaller than usual, pockets of infection in Cambodia, Bangladesh, India, West Africa and southern China.

The influenza virus changes year to year through antigenic drift (genetic variation), so vaccines need constant updating. The efficacy of the vaccine is dependent on many factors, including whether strains included in the vaccine are similar to those circulating in the community. The influenza vaccines currently available in Australia contain four strains of the virus: two influenza A subtypes and two influenza B lineages.

In 2020, we saw unprecedented demand for influenza vaccination while the COVID-19 vaccine was being developed. But Professor Subbarao sounds a further note of caution given that when it came to determining which strains to include in this year’s vaccine, a decision had to be made in September of 2020  based on data that were more limited than usual.

When it comes to scheduling your patients’ important vaccinations, as has been well documented, there should be a two-week break between COVID-19 and influenza vaccinations. The National Immunisation Program (NIP) advises that people aged 6 months to 65 years should receive a standard influenza vaccine, and those aged over 65 should receive the adjuvanted influenza vaccine, but may receive a standard influenza vaccine if the adjuvanted vaccine is unavailable.

Patients living with severe asthma, cystic fibrosis, bronchiectasis, suppurative lung disease, chronic obstructive pulmonary disease (COPD) or chronic emphysema are eligible for free influenza vaccination under the NIP. See the Australian Immunisation Handbook for advice on people who are strongly recommended to receive annual influenza vaccination but are not eligible for NIP-funded vaccines.

Patients living with lung cancer are likely to be immunocompromised due to their condition and treatment. Guidelines vary depending on age, vaccination history and treatment, so while it is recommended that patients with lung cancer receive the annual influenza vaccine, it is appropriate to consult their treating specialist about the best timing and to refer to the Australian Immunisation Handbook.

When it comes to pneumococcal disease, there are two vaccines available: Prevenar 13 (13 valent pneumococcal conjugate vaccine, 13vPCV, covers 13 strains of the disease; Pfizer) and Pneumovax 23 (23 valent pneumococcal polysaccharide vaccine, 23vPPV, covers 23 strains; MSD).

As of July 2020, there were changes in the recommendations for people with risk conditions, Aboriginal and Torres Strait Islander people, and older adults as well as changes in funding via the NIP (further details  regarding the changes are available through the Australian Technical Advisory Group on Immunisation [ATAGI]).

Many children and adults with risk conditions are eligible for funded doses of 13vPCV and 23vPPV. However, some people with high risk conditions for whom the vaccine is recommended are not eligible to receive NIP-funded vaccine doses. This is because clinical advice provided by ATAGI has determined that the incidence of pneumococcal disease for  these conditions is not sufficient to meet cost-effectiveness thresholds.

Those eligible for a free pneumococcal vaccine include people with suppurative lung disease, bronchiectasis and cystic fibrosis. Chronic respiratory conditions identified as at-risk but not funded for pneumococcal disease vaccination under the NIP include COPD and chronic emphysema, all levels of severity of asthma, and interstitial and fibrotic lung disease.

The recommendation for vaccinating healthy non-Indigenous Australian adults over 70 years of age (previously 65 years) is with one dose of 13vPCV, funded under the NIP, even if they have previously had 23vPPV (Pneumovax).

The recommendation for people with NIP-funded medical risk factors, as outlined in the Australian Immunisation Handbook, as well as for healthy Aboriginal and Torres Strait Islander adults aged 50 years or  over, is one dose of 13vPCV, one dose of 23vPPV 12 months later and a second dose of 23vPPV at least 5 years later again. The number of lifetime doses of 23vPPV is limited to two doses for all who are recommended to receive it.

Through its winter immunisation campaign, “Prevention is your best medicine”, the Lung Foundation Australia has developed a Vaccination Tracker to encourage patients to have informed conversations with doctors. Join the Lung Foundation Australia on Wednesday, June 16 (6–7 pm, AEST) for a free webinar on the importance of updating vaccinations, in particular for patients with chronic lung disease and First Nation’s people; register and find other resources here.

Dr Kerry Hancock has a special interest in respiratory medicine and co-chairs the Lung Foundation Australia’s Primary Care Clinical Advisory Committee. Her practice, Chandlers Hill Surgery, was named Australian General Practice of the Year in 1999.

Professor Christine McDonald AM is director of the Department of Respiratory and Sleep Medicine at Austin Health and medical director of the Institute for Breathing and Sleep, Victoria. She chairs Lung Foundation Australia’s COPD Clinical Advisory Committee.

The statements or opinions expressed in this article reflect the views of the authors and do not represent the official policy of the AMA, the MJA or InSight+ unless so stated.