Over the last two years the team prepared by developing protocols for the retrospective and prospective pilot studies. The aim for these studies is to investigate the (potential) vaccine-preventable disease burden in ageing adults.

The retrospective study

The team will first conduct a pilot in two regions: Denmark and the Valencia region in Spain. The study protocol synopsis was submitted during the second year of the project. Based on the initial research, the consortium decided to focus on Pneumococcal pneumonia (PP) and Invasive extra-intestinal pathogenic Escherichia coli Disease (IED) for the retrospective pilot study.

To develop the protocol for implementing the eHR database in their pilot studies the team had to be built on disease progression models (or outcome trees) for the two diseases of interest. These outcome trees described the disease progression pathways over time by chronologically ordering all health states associated with the disease of interest. The constructed trees for PP and EID used standard definitions and description of diseases progressions from experts consultation and literature review.

Protocols were approved by the Ethical Committees and requests were made to data providers in Denmark and Valencia region, in order to have the retrospective pilot studies initiated in the third year of VITAL.

Currently the team submitted an article on ‘European data sources for computing of (potential) vaccine-preventable diseases in ageing adults’ to be published in VACCINE.

The prospective study

During the last year, Sanofi Pasteur and the WP1 team prepared the pilot prospective study. The study aims to assess the impact of Acute Respiratory Infection (ARI) and bacteremia hospitalization on quality of life, frailty and disability in the ageing population. It  is a longitudinal observational study in multiple hospital centers across 3 European countries (France, Italy and Spain). It includes patients aged 65 years or older from the emergency, infectious disease, internal medicine or geriatric hospital wards with bacteraemia and/or ARI.

Two controls are foreseen for every case; the typical control patient will be of the same age and same sex, without suspicion of infection and hospitalized during the past or upcoming month in the same center. All cases and controls will be followed up after six months, and quality of life and frailty will be longitudinally assessed using standardized instruments. The study started in December 2020.