Eurosurveillance - Volume 27, Issue 39, 29 September 2022

After an outbreak of the SARS-CoV-2 Beta variant in the district of Schwaz/Austria, vaccination with Comirnaty vaccine (BNT162b2 mRNA, BioNTech-Pfizer) had been offered to all adult inhabitants (≥ 16 years) in March 2021. This made Schwaz one of the most vaccinated regions in Europe at that time (70% of the adult population took up the offer). In contrast, all other Austrian districts remained with low vaccine coverage.

We studied whether this rapid mass vaccination campaign provided indirect protection to unvaccinated individuals such as children (< 16 years) living in the same district.

To study the effect of the campaign we used two complementary approaches. We compared infection rates among the population of children (< 16 years) in Schwaz with (i) the child population from similar districts (using the synthetic control method), and (ii) with the child population from municipalities along the border of Schwaz not included in the campaign (using an event study approach).

Before the campaign, we observed very similar infection spread across the cohort of children in Schwaz and the control regions. After the campaign, we found a significant reduction of new cases among children of −64.5% (95%-CI: −82.0 to −30.2%) relative to adjacent border municipalities (using the event study model). Employing the synthetic control method, we observed a significant reduction of −42.8% in the same cohort.

Our results constitute novel evidence of an indirect protection effect from a group of vaccinated individuals to an unvaccinated group.

The European Centre for Disease Prevention and Control (ECDC) systematically collates information from sources to rapidly detect early public health threats. The lack of a freely available, customisable and automated early warning tool using data from Twitter prompted the ECDC to develop epitweetr, which collects, geolocates and aggregates tweets generating signals and email alerts.

This study aims to compare the performance of epitweetr to manually monitoring tweets for the purpose of early detecting public health threats.

We calculated the general and specific positive predictive value (PPV) of signals generated by epitweetr between 19 October and 30 November 2020. Sensitivity, specificity, timeliness and accuracy and performance of tweet geolocation and signal detection algorithms obtained from epitweetr and the manual monitoring of 1,200 tweets were compared.

The epitweetr geolocation algorithm had an accuracy of 30.1% at national, and 25.9% at subnational levels. The signal detection algorithm had 3.0% general PPV and 74.6% specific PPV. Compared to manual monitoring, epitweetr had greater sensitivity (47.9% and 78.6%, respectively), and reduced PPV (97.9% and 74.6%, respectively). Median validation time difference between 16 common events detected by epitweetr and manual monitoring was -48.6 hours (IQR: −102.8 to −23.7).

Epitweetr has shown sufficient performance as an early warning tool for public health threats using Twitter data. Since epitweetr is a free, open-source tool with configurable settings and a strong automated component, it is expected to increase in usability and usefulness to public health experts.

Diagnoses of bacterial sexually transmitted infections (STIs) have increased in France since the 2000s. The main strategy to control STI transmission is recommending/facilitating access to condom use, testing, and antibiotic treatments.

This study analyses the evolution of STI testing in the private sector in France from 2006 to 2020.

National health insurance reimbursement data were used to determine numbers and rates of individuals aged ≥ 15 years tested for diagnoses of chlamydia, gonorrhoea and syphilis in the private sector in France and to describe their evolution from 2006 to 2020.

Upward tendencies in testing were observed from 2006 to 2019 for all three STIs. The highest testing rates were identified in people aged 25‒29-years old. The observed testing-increase from 2017 to 2019 was twice as high in young people (< 25 years old) as in older people. In 2019, chlamydia, gonorrhoea and syphilis testing rates were respectively 45.4 (+ 21% since 2017), 41.3 (+ 60%), and 47.2 (+ 22%) per 1,000 inhabitants. For all STIs combined, the number of tested individuals decreased by 37% between March and April 2020 during the first COVID-19 epidemic wave and lockdown in France.

Improvements found in STI testing rates may have resulted from better awareness, especially among young people and health professionals, of the importance of testing, following prevention campaigns. Nevertheless, testing levels remain insufficient considering increasing diagnoses. In 2020, the COVID-19 pandemic had a considerable impact on STI testing. Partner notification and offering diverse testing opportunities including self-sampling are essential to control STI epidemics particularly in exposed populations.