ABSTRACT
Objective:
To understand the molecular
transmission characteristics of
human immunodeficiency virus (
HIV)/
acquired immunodeficiency syndrome(
AIDS)
patients in the mountainous area of southwest Zhejiang Province(Lishui city).
Methods:
A total of 147
blood samples were collected from newly-diagnosed
HIV-1 infected
who received no
antiviral therapy, and
pol gene was amplified, followed by sequencing. MEGA6.0
software was used to construct
phylogenetic tree and determine
gene subtypes. HIVDB online was used to analyze
drug resistance mutation, then the pairwise genetic distance(GD) was calculated and the opitimal threshold of GD was selected, finally the molecular
transmission network was constructed by Cytoscape3.7.0
software. Chi-square or Fisher′s exact
probability method was used for
statistical analysis.
Results:
A total of 134 sequences were obtained successfully, and nine subtypes were detected. The dominant subtypes were CRF08_BC (34.33%, 46/134), CRF01_AE (29.85%, 40/134) and CRF07_BC (23.88%, 32/134). It also found that age, registered residence,
education level and
transmission route had significant differences in distribution of subtypes ( P<0.05). Nineteen
drug resistance individuals were found, and the total
drug resistance rate was 14.18% (19/134). The
HIV-1 molecular
transmission network was plotted based on 1.2% GD threshold. A total of 15
transmission clusters (cluster size ranging from 2 to 29) were found. The network access rate was 49.25% (66/134), mainly including
male (75.76%, 50/66),
heterosexual (81.82%, 54/66) and patientsrinfected with CRF08_ BC (50.00%, 33/66). A
transmission cluster including two cases of
female sex workers and seven cases of
drug resistance was identified, in which the average age of the
patients was 57.21 years old and the average degree value was 22.7, and the cases were mainly infected through
heterosexual contact (96.55%, 28/29). The highest homology of the sequences in the cluster was in Yunnan.
Conclusions:
The
HIV-1 subtypes were diverse in the mountainous area of southwest Zhejiang Province(Lishui city).
Drug resistant
transmission had reached a moderate
epidemic level. There were molecular
transmission clusters with the aggregation characteristics of
elderly clients in specific regions. It was urgent to formulate and implement precise intervention
strategies to curb the spread of
HIV.