Near Real-Time Detection of Molecular HIV-1 Transmission Clusters in Cyprus: Outbreak Detection and Response Using Phylogenetic-Based Analyses from the Cyprus HIV-1 Transmission Cohort Study (CHICS)

In Cyprus, the number of newly infected individuals has nearly tripled since the early 2000s, reaching to 85 new cases in 2018. Advanced phylogenetic-based analyses of HIV-1 genomic sequences from HIV-1 sequence databases provide detailed knowledge of HIV-1 transmission dynamics in human populations which is important in identifying outbreaks and populations at risk and also in better designing intervention strategies.

The Cyprus HIV Transmission Cohort Study (CHICS) is a densely sampled prospective cross-sectional HIV-1 transmission database of newly-diagnosed patients in Cyprus that enables detailed phylogenetic clustering molecular studies in order to reveal HIV-1 transmission dynamics in Cyprus in near real-time. HIV-1 Transmission clusters (or molecular clusters) are identified based on low nucleotide genetic distance and high branch support. We are using this front-line technology to detect and respond to clusters of HIV-1 transmission in Cyprus. This is an important accomplishment to bring Cyprus closer to the goal of no new HIV-1 infections.

Monthly reports on the growth and characteristics of HIV-1 transmission clusters (molecular clusters) are generated by our laboratory and distributed to public health officers and also posted below. The results of this study have a direct impact on the clinical care of HIV-1-infected patients in Cyprus and further advance the implementation of HIV-1 strategies such as treatment-as-prevention and pre-exposure prophylaxis (PrEP) to interrupt the spread of HIV-1 transmission in Cyprus.

The study was approved by and is in accordance with the guidelines and regulations of the Cyprus National Bioethics Committee and the Office of the Commissioner for Personal Data Protection in Cyprus, and in accordance with the written consent of all participating study subjects. Study subjects are presented by a unique laboratory number to protect anonymity.

The monthly reports documenting the HIV-1 transmission hotspots (molecular clusters) in Cyprus are available below: