Characterisation of HIV-1 transmission clusters and drug-resistant mutations in Denmark, 2004 to 2016

Abstract

This study describes the prevalence of human immunodeficiency virus (HIV) drug resistance mutations among 1,815 patients in Denmark from 2004 to 2016 and characterises transmission clusters. POL sequences were analysed for subtype, drug resistance mutations and phylogenetic relationship. The prevalence of surveillance drug resistance mutations (SDRM) was 6.7%, while the prevalence of drug resistance mutations (DRM) with a clinical impact was 12.3%. We identified 197 transmission clusters with 706 patients. Patients 40 years or older were less likely to be members of a transmission cluster and patients in transmission clusters were less likely to be infected abroad. The proportion of late presenters (LP) was lower in active compared with inactive clusters. Large active clusters consisted of more men who have sex with men (MSM), had members more frequently infected in Denmark and contained a significantly lower proportion of LP and significantly fewer patients with DRM than small active clusters. Subtyping demonstrated that the Danish HIV epidemic is gradually becoming more composed of non-B subtypes/circulating recombinant forms. This study shows that active HIV-1 transmission has become increasingly MSM-dominated and that the recent increase in SDRM and DRM prevalence is not associated with more sustained transmission within identified transmission networks or clusters.

Prevalence of transmitted HIV-1 drug resistance among treatment-naive individuals in China, 2000-2016

“…Primary infection with transmitted drug resistant (TDR) HIV strains limits a newly-diagnosed patient's treatment options and is associated with treatment failure. Previous studies have shown that China had a prevalence of HIV with TDR of approximately 3.6% in ART-naive patients in 2015 [8,9], which was lower than that in Western countries [10][11][12][13]. However, given the large number of HIV-infected people and the persistent circulation of HIV in China, the number of patients for whom ART failed because of drug resistance is considerably high in this country.…”

Identification of risk factors associated with national transmission and late presentation of HIV-1, Denmark, 2009 to 2017

“…In Denmark, the rate has decreased slightly from 5.2 to 4.3 per 100,000 inhabitants per year during the same time period. Recent phylogenetic investigations have provided new insights into the dynamics and drivers of local transmissions [9][10][11][12], including that the Danish national transmissions are still mainly caused by HIV-1 subtype B [11]. In order to reduce the number of new HIV-1 infections, more knowledge is needed about which risk groups are causing this persistent transmission.…”

SARS-CoV-2 Molecular Transmission Clusters and Containment Measures in Ten European Regions during the First Pandemic Wave

“…MTCs have been used to examine the likely impact of genetic (mutations and subtypes of viruses) [ 27 , 28 , 29 ], demographic and clinical [ 22 , 25 , 26 ] factors on regional phylogenetic clustering. Identification of MTCs for HIV has resulted in the characterization of the risk factors that are associated with the spread of the virus in different countries [ 22 , 30 , 31 ]. As for SARS-CoV-2, an analysis of 3184 sequences from Japan with complete metadata, revealed that the primary source of clusters are healthcare facilities such as hospitals and care facilities such as nursing homes [ 32 ].…”