A latent class approach to identify multi‐risk profiles associated with phylogenetic clustering of recent hepatitis C virus infection in Australia and New Zealand from 2004 to 2015

Abstract

IntroductionOver the last two decades, the incidence of hepatitis C virus (HCV) co‐infection among men who have sex with men (MSM) living with HIV began increasing in post‐industrialized countries. Little is known about transmission of acute or recent HCV, in particular among MSM living with HIV co‐infection, which creates uncertainty about potential for reinfection after HCV treatment. Using phylogenetic methods, clinical, epidemiological and molecular data can be combined to better understand transmission patterns. These insights may help identify strategies to reduce reinfection risk, enhancing effectiveness of HCV treatment as prevention strategies. The aim of this study was to identify multi‐risk profiles and factors associated with phylogenetic pairs and clusters among people with recent HCV infection.MethodsData and specimens from five studies of recent HCV in Australia and New Zealand (2004 to 2015) were used. HCV Core‐E2 sequences were used to infer maximum likelihood trees. Clusters were identified using 90% bootstrap and 5% genetic distance threshold. Multivariate logistic regression and latent class analyses were performed.ResultsAmong 237 participants with Core‐E2 sequences, 47% were in a pair/cluster. Among HIV/HCV co‐infected participants, 60% (74/123) were in a pair/cluster, compared to 30% (34/114) with HCV mono‐infection (p < 0.001). HIV/HCV co‐infection (vs. HCV mono‐infection; adjusted odds ratio (AOR), 2.37, 95% confidence interval (CI), 1.45, 5.15) was independently associated with phylogenetic clustering. Latent class analysis identified three distinct risk profiles: (1) people who inject drugs, (2) HIV‐positive gay and bisexual men (GBM) with low probability of injecting drug use (IDU) and (3) GBM with IDU & sexual risk behaviour. Class 2 (vs. Class 1, AOR 3.40; 95% CI, 1.52, 7.60), was independently associated with phylogenetic clustering. Many clusters displayed homogeneous characteristics, such as containing individuals exclusively from one city, individuals all with HIV/HCV co‐infection or individuals sharing the same route of acquisition of HCV.ConclusionsClusters containing individuals with specific characteristics suggest that HCV transmission occurs through discrete networks, particularly among HIV/HCV co‐infected individuals. The greater proportion of clustering found among HIV/HCV co‐infected participants highlights the need to provide broad direct‐acting antiviral access encouraging rapid uptake in this population and ongoing monitoring of the phylogeny.

Review on the molecular epidemiology of sexually acquired hepatitis C virus infection in the Asia‐Pacific region

“…Detail of the search results is shown in the flowchart (Figure 1). In total, 13 articles published from 2010 to 2019 were included, comprising 12 cross‐sectional studies and one cohort study [13‐25]. Among them, two were multi‐centre and 11 were city‐based.…”

“…Genetic diversity was noted with at least three variants recorded in each country/city, except for Surabaya, where all sequences therein belonged to only two subtypes (1b and 3k respectively) [22]. The prevalent genotypes of sexually acquired HCV were similar to those in the general population in Australia and New Zealand [13], China [14‐19], Japan [23], Pakistan [24] and Taiwan [20,25,26] (Table 3).…”

“…Of the 13 studies included in this review, six (46.2%) involved phylogenetic analysis in the design [13,15,17,20,23,25]. In these studies, the pattern of association between reported sexual risk and injection behaviours with HCV transmission differed among the places.…”

“…In these studies, the pattern of association between reported sexual risk and injection behaviours with HCV transmission differed among the places. Overlapping risk profile was shown in four out of nine countries/cities, whereas shared transmission networks between the two risk groups were phylogenetically confirmed only in the Australian‐New Zealand [13] study, as summarized in the following paragraphs.…”

Sexually transmitted hepatitis C virus infections: current trends, and recent advances in understanding the spread in men who have sex with men

“…Furthermore, declaring injecting drug use does not equate to sharing injection equipment. Viral sequences collected in Australia and New Zealand suggest that HCV transmission occurs through discrete networks, particularly among HIV and HCV co‐infected individuals . In this study, three distinct risk profiles based on the molecular analysis were described: PWID, HIV‐positive MSM with low probability of injecting drug use, and MSM with both injecting drug use and sexual risk behaviour.…”