Aysén region reports sharp rise in syphilis cases in Chile

The Aysén region in Chile is experiencing a significant surge in syphilis cases, recording the second-highest incidence rate in the country at 90.1 cases per 100,000 inhabitants. According to the Ministry of Health’s 2025 epidemiological report, Aysén’s rate exceeds the national average of 55.2 cases per 100,000 and represents an 8.8-fold increase since 2021.

Deputy Alejandra Valdebenito has formally requested the Undersecretariat of Public Health to provide a detailed action plan and data breakdown by commune, sex, and age group. The inquiry seeks to determine if the spike is due to increased actual transmission, improved testing and notification capabilities, or a combination of both.

Health experts, including María Carolina Rodríguez from Universidad Andrés Bello, have noted that while increased testing may contribute to higher numbers, the magnitude and concentration among young people suggest a real rise in transmission. Syphilis, caused by Treponema pallidum, can lead to severe reproductive, neurological, and perinatal complications, and can be transmitted from pregnant individuals to fetuses.