Sexually transmitted infections: the long wave shaking Europe

Sexually transmitted infections (STIs) represent a global public health problem due to their high prevalence, the potential for serious sexual and reproductive health complications if left untreated, but also the increasing antimicrobial resistance to current treatments. There is, therefore, an urgent need for new preventive interventions. Urging them is the European Centre for Disease Prevention and Control (ECDC), pointing out that over the last decade, bacterial STIs have continued to increase in the EU to a record level of more than 370,000 cases in 2023, with overall notification rates increasing by 16% for chlamydia, 138% for gonorrhoea and 53% for syphilis since 2019. Men who have sex with men make up 73% of syphilis cases, 58% of gonorrhoea cases and 20% of chlamydia cases.

'Over the past decade,' the ECDC explains, 'gonorrhoea and syphilis notifications have fluctuated at considerably lower levels among heterosexual populations. However, an increase in gonorrhoea notifications was observed in 2022 and 2023, particularly among individuals aged between 20 and 24 years'. And even in Italy, doctors have raised the alarm about the spread of syphilis, with Spain and Germany in the lead in terms of absolute numbers of infections (over 10,000 and 9,000 respectively), followed by Italia with 2,538 diagnoses.

However, if we look at the incidence on the population, the geography changes: Luxembourg and Malta lead the ranking, while Italia slips to nineteenth place with 4.3 cases per 100,000 inhabitants. A figure that should not, however, reassure. After a phase of relative stability between 2006 and 2015, in fact, infections in our country have been growing steadily again since 2016, interrupted only temporarily by the effects of the pandemic.

This is why public health responses in countries that have experienced an increase in infections, according to the ECDC, must include 'interventions to make young people aware of the risks of STIs, the importance of safe sexual practices, and the need for timely testing following possible exposure'.

In Seattle, Italia researcher Lorenzo Giacani heads the main laboratory studying syphilis and aims to develop a vaccine. Meanwhile, he has created attenuated strains of the bacterium and identified the mechanism by which the bacterium manages to evade the immune system.