Encouraging vaccination electronically: an encouraging Danish model

In France, the entire territory, with the exception of Martinique which is still in the pre-epidemic phase, is affected by an influenza epidemic according to an SPF press release on December 26. In week 51, 2% of electronically certified deaths mentioned the flu, compared to only 0.5% the previous week. To contain this epidemic, vaccination has been recommended since October 14. However, for the health organization, during the 2023/2024 season, 54% of people aged 65 and over were vaccinated, compared to only 25.4% of those under 65.

Electronic vaccination incentive delivers significant results

Among 299,881 Danish participants aged 18 to 64 (median age 52.0) with a chronic illness, 39.6% of those who received an e-letter got vaccinated, compared to just 27.9 % in the group that did not receive any letters (a significant increase of 11.7 percentage points). The study, carried out between September 24, 2023 and May 31, 2024, took into account vaccinations carried out no later than December 1, 2024 for this vaccination season.

However, the researchers specify in the study that “despite the observed large increase in influenza vaccination coverage, interventions generally did not result in differences in our prespecified exploratory assessment of clinical outcomes.”

The signature of a doctor as well as a known and government sender are incentive elements of the email

The electronic letters were all sent on September 24, 2023, one week before the start of the Danish vaccination period. The shipping procedure used an official government system, to ensure the credibility of the message according to the study authors. Moreover, let us point out that the Danes are used to receiving and recognizing these emails from the country’s health authority. To reinforce this credibility, the letters were signed by specialist doctors. Finally, the letters included a direct link to the vaccination booking platform, as well as an option to make an appointment by telephone.

Repeats of the expedition and information on cardiovascular risks further encourage vaccination.

Six different letter models were used. Among them, the letter resent a second time 10 days after the first, gave the best results with a vaccination rate reaching 41.8%, an increase of 13.9 percentage points compared to the control group. Another effective model highlighted the potential cardiovascular benefits of vaccination, reaching a rate of 39.8%.

A large-scale study on the impact of electronic letters

Already studied for the 2022/2023 flu season, this strategy was published in 2023 in The Lancet. It showed that people aged 65 and over were more vaccinated when they received an email from the Danish government. However, the observed increase was more moderate, as more than 80% of Danes in this age group were already vaccinated.

For the 2023/2024 season, the study also targeted patients with a history of myocardial infarction. The results, published in JAMA Cardiology in November, reveal similar trends: patients who received the electronic letter were vaccinated more. These findings reinforce the idea that digital reminders can be effective even in already sensitized populations

Study biases limit its transposition outside Denmark

Some people may not have been aware of their eligibility for free vaccination before receiving the letter. This could explain part of the observed increase, regardless of the form and content of the letter. In addition, the researchers recognize another bias in the study and specify that “ With citizens legally obligated to read and respond to important government messages transmitted through this system, our interventions may have been viewed with increased importance ».

How did Danish researchers gain access to patients?

The study relied on Danish national administrative registers, considered comprehensive and of high quality. As part of this study, the researchers obtained special permissions to use these data without individual consent, while respecting current ethical and legal guidelines. “ The Danish Health Data Authority has granted access to national registry data and approved the content of intervention letters “, we can read in the article.

https://www.whatsupdoc-lemag.fr/article/vers-une-gestion-simplifiee-du-diabete-de-type-2-linsuline-hebdomadaire-confirme-son

Electronically targeting populations in France, is it possible?

Implementing a similar strategy in France would require access to health databases and the use of a secure electronic platform for transmitting letters. Currently, the MSSanté secure messaging system could be used for this type of communication. However, legislative and logistical adjustments may be necessary to ensure confidentiality rules are respected and facilitate the identification of eligible patients. Such an approach could improve vaccination rates, particularly among vulnerable and under-vaccinated populations.

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