BACKGROUND: It has been reported that the increase in human immunodeficiency virus (HIV) sequence diversity in drug resistance surveillance specimens may be used to classify the duration of HIV infection as <1 or >1 year. We describe a mixed base classifier (MBC) optimized to categorize the duration of subtype B infections as <6 or >6 months on the basis of sequences for drug resistance surveillance specimens and compared MBC findings with those of serologic methods. METHODS: The behavior of the MBC was examined across a range of thresholds for calling mixed bases. MBC performance was then evaluated using either complete pol sequences or sites reflecting evolutionary pressures (HLA selection sites, sites that increased in entropy over the course of infection, and codon positions). RESULTS: The MBC performance was optimal when secondary peaks on the sequencing chromatogram accounted for at least 15% of the area of primary peaks. A cutoff of <0.45% mixed bases in the pol region best identified recent infections (sensitivity = 82.7%, specificity = 78.8%), with improvement achieved by analyzing only sites that increased in entropy. CONCLUSIONS: In an extended data set of 1354 specimens classified by BED, the optimized MBC performed significantly better than a simple MBC (agreement, 68.98% vs 67.13%). If further validated, the MBC may prove beneficial for detecting recent infection and estimating the incidence of HIV infection.
BACKGROUND: It has been reported that the increase in human immunodeficiency virus (HIV) sequence diversity in drug resistance surveillance specimens may be used to classify the duration of HIV infection as <1 or >1 year. We describe a mixed base classifier (MBC) optimized to categorize the duration of subtype B infections as <6 or >6 months on the basis of sequences for drug resistance surveillance specimens and compared MBC findings with those of serologic methods. METHODS: The behavior of the MBC was examined across a range of thresholds for calling mixed bases. MBC performance was then evaluated using either complete pol sequences or sites reflecting evolutionary pressures (HLA selection sites, sites that increased in entropy over the course of infection, and codon positions). RESULTS: The MBC performance was optimal when secondary peaks on the sequencing chromatogram accounted for at least 15% of the area of primary peaks. A cutoff of <0.45% mixed bases in the pol region best identified recent infections (sensitivity = 82.7%, specificity = 78.8%), with improvement achieved by analyzing only sites that increased in entropy. CONCLUSIONS: In an extended data set of 1354 specimens classified by BED, the optimized MBC performed significantly better than a simple MBC (agreement, 68.98% vs 67.13%). If further validated, the MBC may prove beneficial for detecting recent infection and estimating the incidence of HIV infection.
Authors: Ethan Obie Romero-Severson; Cody Lee Petrie; Edward Ionides; Jan Albert; Thomas Leitner Journal: Int J Epidemiol Date: 2015-07-10 Impact factor: 7.196
Authors: Peter Rusert; Roger D Kouyos; Claus Kadelka; Hanna Ebner; Merle Schanz; Michael Huber; Dominique L Braun; Nathanael Hozé; Alexandra Scherrer; Carsten Magnus; Jacqueline Weber; Therese Uhr; Valentina Cippa; Christian W Thorball; Herbert Kuster; Matthias Cavassini; Enos Bernasconi; Matthias Hoffmann; Alexandra Calmy; Manuel Battegay; Andri Rauch; Sabine Yerly; Vincent Aubert; Thomas Klimkait; Jürg Böni; Jacques Fellay; Roland R Regoes; Huldrych F Günthard; Alexandra Trkola Journal: Nat Med Date: 2016-09-26 Impact factor: 53.440
Authors: Yen T Duong; Reshma Kassanjee; Alex Welte; Meade Morgan; Anindya De; Trudy Dobbs; Erin Rottinghaus; John Nkengasong; Marcel E Curlin; Chonticha Kittinunvorakoon; Boonyos Raengsakulrach; Michael Martin; Kachit Choopanya; Suphak Vanichseni; Yan Jiang; Maofeng Qiu; Haiying Yu; Yan Hao; Neha Shah; Linh-Vi Le; Andrea A Kim; Tuan Anh Nguyen; William Ampofo; Bharat S Parekh Journal: PLoS One Date: 2015-02-24 Impact factor: 3.240