Vaccine fatigue leaves Singapore vulnerable to falling ill

[The_King]

SINGAPORE: Although this is the season to be jolly among many, this is also the season our healthcare professionals and system are embracing surges of patients with acute respiratory infections.

In the week leading up to Christmas, the average daily number of patients seeking treatment in polyclinics for acute respiratory infection was 3,475, an increase of 30 per cent over the four weeks before, according to the Ministry of Health’s weekly infectious diseases bulletin

 

These patients could be infected by one or more respiratory pathogens that may cause flu, pneumococcal disease or COVID-19. The severity of these infectious diseases can be minimised by vaccinations. Yet, according to the Health Ministry, vaccination rates against COVID-19 have been falling recently. This trend is concerning and vaccine fatigue may be one of the reasons.

THE IMPACT OF VACCINE FATIGUE

Vaccine fatigue can be defined as a transitional stage from vaccine acceptance to vaccine hesitancy on the uptake of additional updated booster shots.

Vaccine fatigue usually applies to individuals who already have had at least two doses of vaccine against a specific or a panel of infectious pathogens. It can be due to fear of previous episodes of side effects, misinformation and disinformation on low effectiveness and non-urgency of booster vaccines during the endemic phase.

While the majority of these respiratory infections may be self-limiting, a proportion can be severe, even lethal, especially for the more vulnerable populations such as the elderly or those with underlying medical conditions, or a weakened immune system.

The recent surge of COVID-19 cases has led to an increase in the average daily ICU admissions. Among those admitted, most of the deaths occurred among the elderly aged 60 and above.

OTHER FACTORS FOR COVID-19 SURGE

Besides vaccine fatigue, the recent surge in COVID-19 cases can also be attributed to a few other factors.

First, decreasing herd immunity in the population. Immunity from the vaccine typically wanes over a period of up to a year after each dose. Coupled with the slower uptake of the recent booster vaccine, herd immunity can be challenging to maintain.

The Singapore government has updated its COVID-19 vaccine recommendations, encouraging people aged six months and above to receive an additional dose in 2023 or 2024.

The current updated booster vaccine is able to provide effective immunity against the Omicron XBB 1.5. subvariant strains as well as cross-protection immunity against other circulating Omicron subvariant strains, reducing the risk of disease severity.

As reported by the World Health Organization (WHO), a recent surge of the JN.1 subvariant is likely to circulate more predominately globally, and replacing other subvariants.

 

 

While evidence is still lacking on the cross-protection immunity of the most recent vaccine against the JN.1 subvariant, both the WHO and the US Centers for Disease Control and Prevention expect the updated COVID-19 vaccine to remain effective. This is based on the limited differences in the virus’ genetic mutations assessed through next-generation sequencing technology as part of ongoing surveillance strategy.

With new subvariants evolving constantly, a population with a lowered herd immunity would likely experience new surges of cases yearly, similar to the influenza transmission during the winter seasons of the Northern and Southern hemispheres.

Second, the year-end travels and festive gatherings have increased the risk of exposure and transmission of COVID-19 within a short period of time at a specific location, akin to a super-spreading event.

Lastly, growing complacency as we have been living in the endemic phase since early 2023. A “false sense of security” reduces the motivation for one to take up additional booster shots. This has also led to a drop in compliance over time for personal prevention measures such as masking up in crowded indoor settings, self-isolation when ill and practising frequent handwashing with soap.

VACCINE FATIGUE CAN BE MINIMISED

A recent study published in the journal Nature Medicine suggested that a vaccine mandate is not likely to overcome vaccine fatigue, but instead may create negative sentiment and mistrust about the vaccine and government during endemicity.

 

To reduce vaccine fatigue, the study suggested increasing awareness of updated vaccines, providing free and easy access to vaccines, and the requirement of vaccine passport for travel.

Additionally, strengthening campaign messaging on booster vaccines as well as complementing this with medical consensus and celebrity endorsement would help to remind people of the importance of protecting their vulnerable loved ones.  

A number of these factors are also highlighted in a separate study published in the journal Vaccine on vaccine acceptance. This suggests the importance of adopting the same risk communication strategies that were used to advocate for vaccine uptake during the early phase of the pandemic to increase the uptake of boosters during the endemic period.

One possible approach might be to adopt the strategies that were used to promote childhood immunisation in Singapore. Under the childhood immunisation programme, frequent touchpoints with the paediatrics care team for developmental screening as well as engagement with family physicians and schools served as effective platforms to raise vaccine awareness and disease risk among parents.

Similarly, the Healthier SG programme could serve as an effective platform. Beyond their role in managing population health, family physicians play an important role in educating their patients on the importance of staying up to date with vaccinations to reduce the risk and severity of diseases that could be detrimental to their health.

 

 

PREVENTION MEASURES REMAIN CRITICAL

Despite the high accessibility and availability of a safe booster vaccine against COVID-19, the vaccine is only highly effective in reducing the risk of hospitalisation and disease severity. It is not likely to prevent infection.

Masking up is highly encouraged among all, especially among vulnerable populations in crowded indoor places. Masking up has been found to reduce the risk of infection resulting in COVID-19 by up to 45 per cent in community studies. High compliance towards proper masking is also likely to reduce the risk and transmission of other respiratory infections.

Combining masking with vaccination is likely to be more effective in reducing disease burden due to immunity waning, circulation of new subvariants and vaccine fatigue.   

As we say goodbye to 2023, going for your booster vaccines and masking up will set the stage for an excellent start to the new year.

Dr Vincent Pang Junxiong, Assistant Professor, Centre for Outbreak Preparedness at Duke-NUS Medical School.

Source: CNA/aj

[The_King]

talk until like  vaccine go no side effect.  it true then inject 1 shot per month and we talk after 1 yr