Detection Of Human Immunodeficiency Virus DNA Research Articles

Label-free and portable detection of HIV-DNA by a handheld luminometer

BackgroundThe human immunodeficiency virus (HIV) remains a major worldwide health problem. Nowadays, many methods have been developed for quantitative detecting human immunodeficiency virus DNA (HIV-DNA), such as fluorescence and colorimetry. However, these methods still have the disadvantages of being expensive and requiring professional technicians. Early diagnosis of pathogens is increasingly dependent on portable instruments and simple point-of-care testing (POCT). Therefore, it is meaningful and necessary to develop portable and cheap methods for detecting disease markers. ResultsIn this work, a label-free chemiluminescence (CL) method was developed for detecting HIV-DNA via a handheld luminometer. To achieve label-free target detection, the CL catalyst, G-triplex-hemin DNAzyme (G3-hemin DNAzyme), was in-situ assembled in the presence of HIV-DNA. For improving sensitivity, HIV-DNA induced the cyclic strand displacement reaction (SDR), which can form three G3-hemin DNAzymes in one cycle. So, the chemiluminescence reaction between luminol and H2O2 was highly effectively catalyzed, and the CL intensity was linearly related with the concentration of HIV-DNA in the range of 0.05–10 nM with a detection limit of 29.0 pM. Due to the high specificity of hairpin DNA, single-base mismatch can be discriminated, which ensured the specific detection of HIV-DNA. SignificanceIn-situ formation of G3-hemin DNAzyme led to label-free and selective detection without complex synthesis and functionalization. Therefore, it offers a cheap, selective, sensitive and portable method for detecting disease-related genes, which is promising for POCT of clinical diagnosis in resource-limited settings.

Cell membranes cloaked magnetic nanoparticles for target recycling detection of nucleic acid

Accurate analysis of human immunodeficiency virus (HIV) related molecules are significant for early diagnosis and therapy of acquired immune deficiency syndrome (AIDS). In this work, a novel electrochemical biosensor for HIV DNA detection is developed. Target induced recycling amplification is designed to enhance the sensitivity. Magnetic nanoparticles are used for facile separation, which are first cloaked by red blood cell membranes and then modified with DNA strands. Target initiated formation of multiple DNA three-way junctions occurs at the interface and the nanoconjugates can be conveniently immobilized on the surface of magnetic electrode. The measured responses from electrochemical species carried on the nanoconjugates can be used to reflect the level of target DNA. This proposed electrochemical method shows excellent sensing performances with a linear range from 0.1 fM to 1 pM. The limit of detection is as low as 35 aM. It is also successfully applied in clinical serum samples with satisfactory results. Therefore, this approach has great potential use for point-of-care testing of HIV DNA and provides a general strategy for various virus analysis.

Ultrasensitive detection of HIV DNA using an electrochemical biosensor with branched DNA amplification

This paper presents a novel strategy for ultrasensitive detection of human immunodeficiency virus (HIV) DNA by an electrochemical biosensor. By the shearing cycle of the target DNA (T-DNA), a large amount of complimentary sequence probes (CS probe DNA) are obtained. Then, the Zr4+ functional probe DNA containing many branched DNAs is captured. Next, the initiator α-bromophenylacetic acid is connected to the branched chains of probe DNA by esterification reaction. Numerous electroactive monomers, namely, ferrocenylmethyl methacrylate (FMMA), are produced at the end of the branched chains by electrochemically mediated atomic transfer radical polymerization reaction. The signal of FMMA is greatly enhanced due to a large number of branched chain-loaded probe clusters containing numerous FMMA. T-DNA can be detected with a linear range of 0.1 fM–10 nM with a detection limit of 0.037 fM. The sensor is highly sensitive and selective. It has been applied to the detection of HIV DNA in human serum samples, and it has potential application prospects in the early clinical diagnosis of AIDS.

3-D DNA walker-mediated ultrasensitive dual-signal biosensor for HIV DNA detection

Here, we successfully designed a dual-signal sensing system based on 3-D DNA walker signal amplification and target recycling amplification strategies for ultrasensitive determination of the human immunodeficiency virus（HIV）DNA. The DNA walker is constructed by locked swing arm and track strand onto the surface of the magnetic beads (MBs). After adding HIV DNA, the swing arm was activated to hybridize with the track strand to form ds-DNA, which could be cleaved by Exonuclease III (Exo III) to release G-quadruplex. Subsequently, hemin combined with G-quadruplex to construct DNAzymes, which catalyzed the oxidation of o-phenylenediamine (OPD) into the yellow product 2,3 diaminophenazine (DAP), resulting in the fluorescence quenching of MoS2 QDs at 420 nm, and the fluorescence enhancement of DAP at 560 nm. Therefore, the amounts of HIV DNA can be detected by Uv-vis absorbance and fluorescence dual-signal changes. Besides, each swing arm cleaved multiple track strands to amplify the signal, while the target recycling amplification was also in progress. Such double-amplified signal strategy not only provided excellent sensitivity and selectivity, but also realized magnetic separation, eliminating interferences in complex samples. In addition, our designed sensing platform can detect different DNAs by adjusting the recognition sequence, providing a general strategy for various virus analysis.

Pt/Ti3C2Tx nanozyme-amplified colorimetric lateral flow biosensor for dual-readout detection of HIV-DNA

Rapid and sensitive virus genes detection with point-of-care testing is the key to improving the probability of survival and lowering infectious rate. Here, we proposed a sensitive and quantitative colorimetric lateral flow biosensor (CLFB) for human immunodeficiency virus-DNA (HIV-DNA) detection with a novel nanomaterial (Pt nanoparticles decorated Ti3C2Tx MXene, Pt/Ti3C2Tx) as signal reporters. Pt/Ti3C2Tx was synthesized by a self-reduction method with Ti3C2Tx as both reducing agent and supporter. Each Pt/Ti3C2Tx contained hundreds of Pt nanoparticles to achieve enhanced colorimetric dual-readout, which can not only show gray color itself, but also catalyze its substrate to produce more obvious red color within 3 min. The integration of mimic enzyme property of Pt/Ti3C2Tx improved the colorimetric signal brightness and decreased naked-eye detection limit of HIV-DNA to 0.1 nM relative to original 0.8 nM. Capture DNA was further modified onto the Pt/Ti3C2Tx to realize specific binding with HIV-DNA, enabling the CLFB good reproducibility with an average intra-assay deviation of 4.3% and an inter-assay deviation of 4.2% respectively. Furthermore, the successful detection of HIV-DNA in serum samples demonstrated its great application potential in real samples and timely diagnosis.

Flexible paper-based Ni-MOF composite/AuNPs/CNTs film electrode for HIV DNA detection

It is very important to develop a rapid, simple, low cost point-of-care (POC) method for the early diagnosis of pathogens. In this work, a flexible paper-based electrode based on nickel metal-organic framework (Ni-MOF) composite/Au nanoparticles/carbon nanotubes/polyvinyl alcohol (Ni–Au composite/CNT/PVA) was constructed to detect target human immunodeficiency virus (HIV) DNA by DNA hybridization using methylene blue (MB) as a redox indicator. The CNT/PVA and Ni–Au composite were deposited on the cellulose membrane by vacuum filtration and drop-coating method in turn to obtain Ni–Au composite/CNT/PVA (CCP) film electrode. Compared to the CNT/PVA film electrode, CCP film electrode makes a higher loading of the probe DNA for its large specific surface area and conjugated π-electron system that can provide hydrogen bond sources to achieve interactions between MOF and single-stranded DNA, which improves the sensitivity for detecting target DNA. The variation of peak current for MB molecules adsorbed onto DNA before and after hybridization with HIV DNA was monitored. Electrochemical results proved that the CCP film maintained stable electrochemical property even after bending 200 times or stretching under different strains from 0% to 20%. The flexible paper electrode showed excellent sensing performance with a linear range of 10 nM–1 μM and a low detection limit of 0.13 nM. The target HIV DNA was successfully detected even in complex serum samples using the flexible CCP film electrode. Therefore, the simple and inexpensive flexible paper-based MOF composite film electrode can also be utilized for other pathogens POC diagnosis.

Single-Particle Electrochemical Biosensor with DNA Walker Amplification for Ultrasensitive HIV-DNA Counting.

Single-particle electrochemical collision has gained great achievements in fundamental research, but it is challenging to use in practice on account of its low collision frequency and the interference of the complex matrix in actual samples. Here, magnetic separation and DNA walker amplification were integrated to build a robust and sensitive single-particle electrochemical biosensor. Magnetic nanobeads (MBs) can specifically capture and separate targets from complex samples, which not only ensures the anti-interference capability of this method but also avoids the aggregation of platinum nanoparticles (Pt NPs) caused by numerous coexisting substances. A low amount of targets can lead to the release of more Pt NPs and the generation of more collision current transients, realizing cyclic amplification. Compared with simple hybridization, a DNA walker can improve the collision frequency by about 3-fold, greatly enhancing detection sensitivity, and a relationship between collision frequency and target concentration is used to realize quantification. The biosensor realized an ultrasensitive detection of 4.86 fM human immunodeficiency virus DNA (HIV-DNA), which is 1-4 orders of magnitude lower than that of traditional methods. The successful HIV-DNA detection in complex systems (serum and urine) demonstrated a great promising application in real samples and in the development of new single-entity biosensors.

Enrichment-Stowage-Cycle Strategy for Ultrasensitive Electrochemiluminescent Detection of HIV-DNA with Wide Dynamic Range.

Sensitive detection of human immunodeficiency virus DNA (HIV-DNA) is essential for timely diagnosis and cure of the illness. Herein, a novel "enrichment-stowage-cycle" strategy was proposed to fabricate a multiple amplified electrochemiluminecence (ECL) biosensor for HIV-DNA detection. On the basis of the enrichment role of magnetic nanobeads, assembly role of copolymer nanospheres and strand displacement amplification (SDA), the processes were named as "enrichment", "stowage", and "cycle", respectively. The method employed electrochemiluminescent nanospheres (ENs) as signal labels by assembling three layers of CdSe/ZnS quantum dots (QDs) onto the surface of copolymer nanospheres. Compared to QDs, the same concentration of ENs can the enhance the ECL intensity by about 11.3-fold. SDA could further amplify the signals by about 3.77-fold, possessing high sensitivity for low-abundant biomarkers detection. The integration of magnetic separation improved detection specificity and stability, making the method possible for practical application. On the basis of magnetic separation, ENs and SDA, the ECL biosensor realized ultrasensitive detection of 39.81 fM HIV-DNA, which was more sensitive than other HIV-DNA analytical methods, with a wide dynamic range of 0.05 pM to 50 nM. The successful detection of HIV-DNA in complex samples with good sensitivity and accuracy indicated its potential utilization in early judgment of diseases and fabrication of signal amplification platforms.

A molecularly imprinted electrochemiluminescence sensor for ultrasensitive HIV-1 gene detection using EuS nanocrystals as luminophore

Development of simple, sensitive and specific method for human immunodeficiency virus (HIV) assays are urgently demand. In this study, we developed a novel molecularly imprinted polymer (MIP) electrochemiluminescence (MIP-ECL) sensor for the highly sensitive and selective HIV-1 gene detection using Europium sulfide nanocrystals (EsNCs) as signal producing compound. Here, the HIV aptamer as the template and o-phenylenediamine as the functional monomer, were electropolymerized directly on the surface of ITO electrode. With the hybridization reaction between the assemblies of EuS NCs functionalized 5-amino-labeled oligonucleotides as capture probes and oligonucleotides as detection target (HIV gene), the ECL signal significantly increased using K2S2O8 as coreactant. Taking advantage of both MIP-ECL assays and the strong electrochemiluminescence emission of EuS NCs, the sensitive and selective HIV gene detection has been achieved in a linear range 3.0 fM to 0.3 nM with a detection limit of 0.3 fM. The present MIP-ECL biosensor showed good specificity for HIV DNA detection compared to non-complementary and two bases mismatched sequences. The proposed ECL biosensor was applied to detect of HIV DNA in real human serum samples and satisfactory results were obtained. Due to high sensitivity and selectivity, excellent reproducibility and stability of the proposed assay, EuS NCs can be used as novel luminophore for development of MIP-ECL sensors for detection of other DNA biomarkers.

The development of radio frequency magnetron sputtered p-type nickel oxide thin film field-effect transistor device combined with nucleic acid probe for ultrasensitive label-free HIV-1 gene detection

Sensitive, selective and inexpensive human immunodeficiency virus (HIV) diagnostics are urgently needed for early diagnosis and monitoring of the HIV. We developed a novel label free liquid-ion gated field-effect transistor (FET)-type biosensor for HIV-1 gene detection with the development of p-type semiconducting nickel oxide (NiO) thin film. Initially, reproducible radio frequency (RF) magnetron sputtering technique was used for deposition of NiO nanoscale thin film on the glass substrate. Electrical measurements showed that NiO certainly provided a high carrier mobility (μ), superior subthreshold swing (SS) and high On/Off ratio in FET device. The pH sensing of NiO -FET device was evaluated and then HIV-1, 5′-amino-modified probe single strand DNA (ssDNA) was covalently immobilized on the surface of the NiO thin film. By integration of the advantages of the NiO and liquid-ion gated FET, an efficient DNA HIV biosensor has been achieved for sensitive detection of target HIV DNA at linear range 1.0 aM to 10.0 nM with a detection limit of 0.3 aM. The proposed biosensor exhibited good selectivity even against non-complementary and two-base mismatch sequences and was successfully applied to detect HIV DNA in human serum sample. This device has a promising potential application to monitor other biomarkers in biological fluids and clinical samples.

HIV-related DNA detection through switching on hybridized quenched fluorescent DNA-Ag nanoclusters.

In this paper, DNA containing six cytosines as the formation site for silver nanoclusters (Ag NCs) was adopted as a template for preparing fluorescent DNA-Ag NCs. For the first time, it was found that the fluorescence of DNA-Ag NCs could be quenched after hybridization with their complementary sequence. On the basis of this new phenomenon, we designed a sequence C1 that was completely complementary to human immunodeficiency virus (HIV) DNA, and probe DNA which was partially complementary to C1 for the synthesis of DNA-Ag NCs. The fluorescence of DNA-Ag NCs was quenched after hybridization with C1 and the DNA-Ag NCs/C1 composite was formed, while C1 could be dissociated away from the DNA-Ag NCs by HIV DNA through a strand exchange reaction due to the stronger affinity between HIV DNA and C1, which could switch on the quenched Ag NCs, thus a new "off-on" fluorescence method for HIV DNA detection was developed. In the experiment, the Ag NCs formation site of DNA, the number of base pairs, and the pH and salt concentration of binding buffer were optimized. Under the optimum conditions, the limit of detection for HIV DNA was obtained to be 3.18 nM (3σ/N, n = 7) with the linear range of 15-150 nM for the 150 nM DNA-Ag NCs/C1 probe. Besides, the probe showed excellent specificity to HIV DNA, and even distinguished one nucleotide mismatched HIV DNA.

Polydopamine Nanotubes as an Effective Fluorescent Quencher for Highly Sensitive and Selective Detection of Biomolecules Assisted with Exonuclease III Amplification.

In this work, the effective fluorescence quenching ability of polydopamine nanotubes (PDANTs) toward various fluorescent dyes was studied and further applied to fluorescent biosensing for the first time. The PDANTs could quench the fluorophores with different emission frequencies, aminomethylcoumarin acetate (AMCA), 6-carboxyfluorescein (FAM), 6-carboxytetramethylrhodamine (TAMRA), and Cy5. All the quenching efficiencies reached to more than 97%. Taking advantage of PDANTs' different affinities toward ssDNA and dsDNA and utilizing the complex of FAM-labeled ssDNA and PDANTs as a sensing platform, we achieved highly sensitive and selective detection of human immunodeficiency virus (HIV) DNA and adenosine triphosphate (ATP) assisted with Exonuclease III amplification. The limits of detection (LODs) of HIV DNA and ATP reached to 3.5 pM and 150 nM, respectively, which were all lower than that of previous nanoquenchers with Exo III amplification, and the platform also presented good applicability in biological samples. Fluorescent sensing applications of this nanotube enlightened other targets detection based upon it and enriched the building blocks of fluorescent sensing platforms. This polydopamine nanotube also possesses excellent biocompatibility and biodegradability, which is suitable for future drug delivery, cell imaging, and other biological applications.

DNA tetrahedron and star trigon nanostructures for target recycling detection of nucleic acid.

Human immunodeficiency virus (HIV) is a retrovirus which attacks the human body's immune system and further leads to acquired immunodeficiency syndrome (AIDS). Nucleic acid detection is of great importance in the medical diagnosis of such diseases. Herein, we develop a simple and enzyme-free electrochemical method for the target recycling detection of nuclei acid. DNA tetrahedron and star trigon nanostructures are designed and constructed on the electrode interface for target capture and signal enrichment. This strategy is convenient and sensitive, with a limit of detection as low as 1 fM, and can also successfully distinguish single-base mismatched DNA. Therefore, the proposed method has a promising potential application for HIV DNA detection.

Ultrasensitive Electrochemical Biosensor for HIV Gene Detection Based on Graphene Stabilized Gold Nanoclusters with Exonuclease Amplification.

Because human immunodeficiency virus (HIV) has been one of the most terrible viruses in recent decades, early diagnosis of the HIV gene is of great importance for all scientists around the world. In our work, we developed a novel electrochemical biosensor based on one-step ultrasonic synthesized graphene stabilized gold nanocluster (GR/AuNC) modified glassy carbon electrode (GCE) with an exonuclease III (Exo III)-assisted target recycling amplification strategy for the detection of HIV DNA. It is the first time that GR/AuNCs have been used as biosensor platform and aptamer with cytosine-rich base set as capture probe to construct the biosensor. With the combination of cytosine-rich capture probe, good conductivity and high surfaces of GR/AuNCs, and Exo III-assisted target recycling amplification, we realized high sensitivity and good selectivity detection of target HIV DNA with a detection limit of 30 aM (S/N = 3). Furthermore, the proposed biosensor has a promising potential application for target detection in human serum analysis.

Exonuclease III-based target recycling for ultrasensitive homogeneous monitoring of HIV DNA using Ag+-coordinated hairpin probe

A new homogeneous electrochemical sensing strategy based on exonuclease III-assisted target recycling amplification was utilized for simple, rapid and highly sensitive detection of human immunodeficiency virus (HIV) DNA on an immobilization-free Ag(I)-assisted hairpin DNA through the cytosine-Ag(+)-cytosine coordination chemistry. The assay involved target-induced strand-displacement reaction accompanying dissociation of the chelated Ag(+) in the hairpins and exonuclease III-triggered target recycling. Initially, the added target DNA hybridized with hairpin DNA to disrupt the Ag(I)-coordinated hairpin probe and releases the coordinated Ag(+) ion. Then, the newly formed DNA double-stranded DNA could be cleaved by exonuclease III, and released target HIV DNA, which retriggered the strand-displacement reaction with the hairpin for target recycling, thereby resulting in formation of numerous free Ag(+) ions in the detection cell. The released Ag(+) ions can be readily captured by the negatively charged electrode, and subsequent anodic-stripping voltammetric detection of the captured Ag(+) ions are conducted to form the anodic current for the production of the electronic signal within the applied potential. Under optimal conditions, the exonuclease III-based sensing system exhibited good electrochemical responses for the detection of HIV DNA at a concentration as low as 23 fM.

Sensitive electrochemical monitoring of nucleic acids coupling DNA nanostructures with hybridization chain reaction

Methods based on metal nanotags have been developed for metallobioassay of nucleic acids, but most involve complicated labeling or stripping procedures and are unsuitable for routine use. Herein, we report the proof-of-concept of a novel and label-free metallobioassay for ultrasensitive electronic determination of human immunodeficiency virus (HIV)-related gene fragments at an ultralow concentration based on target-triggered long-range self-assembled DNA nanostructures and DNA-based hybridization chain reaction (HCR). The signal is amplified by silver nanotags on the DNA duplex. The assay mainly consists of capture probe, detection probe, and two different DNA hairpins. In the presence of target DNA, the capture probe immobilized on the sensor sandwiches target DNA with the 3′ end of detection probe. Another exposed part of detection probe at the 5′ end opens two alternating DNA hairpins in turn, and propagates a chain reaction of hybridization events to form a nicked double-helix. Finally, numerous silver nanotags are immobilized onto the long-range DNA nanostructures, each of which produces a strong electronic signal within the applied potentials. Under optimal conditions, the target-triggered long-range DNA nanostructures present good electrochemical behaviors for the detection of HIV DNA at a concentration as low as 0.5fM. Importantly, the outstanding sensitivity can make this approach a promising scheme for development of next-generation DNA sensors without the need of enzyme labeling or fluorophore labeling.

LONGITUDINAL ANALYSIS OF HUMAN IMMUNODEFICIENCY VIRUS TYPE 1 RNA IN BREAST MILK AND OF ITS RELATIONSHIP TO INFANT INFECTION AND MATERNAL DISEASE

Rousseau CM, Nduati RW, Richardson BA, et al. J Infect Dis. 2003;187:741–747Transmission of human immunodeficiency virus (HIV) via breastfeeding may occur throughout lactation. In developing countries, where >90% of HIV-exposed children live, safe alternatives to breastfeeding are not available. An understanding of the dynamics of breast milk virus levels and the correlation of breast milk virus levels with mother-to-child transmission is essential for the development of effective interventions.A total of 648 breast milk samples were collected from 275 women enrolled in a clinical trial in Nairobi, Kenya, between 1992 and 1998. Antiretroviral regimens were not available to the women at the time of the study. Breast milk samples were analyzed for virus levels, and infants were monitored for up to 2 years, for assessment of HIV transmission.The average duration of breastfeeding was 21 months. Of the 275 women, 70 transmitted HIV to their infants and 205 did not. Greater maternal plasma viral loads, lower maternal CD4+ T cell counts, and detection of HIV DNA in maternal genital secretions were significantly associated with elevated breast milk HIV RNA levels. The median viral load in early milk was significantly greater than that in breast milk collected 14 days after delivery. Breastfeeding mothers who transmitted HIV had significantly higher breast milk HIV RNA levels and more consistent viral shedding, compared with mothers who did not transmit HIV.The risk of infant infection through breastfeeding was increased by higher levels of virus in breast milk; levels were highest early after delivery.In developing countries, the rate of perinatal HIV transmission approaches 50%. This is dramatically higher than the 20% to 25% rate of transmission that was noted in developed countries before the initiation of perinatal antiretroviral therapy. It is now clear that breastfeeding is a significant factor in the transmission of HIV from mother to child and may be responsible for ≥30% of transmissions in developing countries. Unfortunately, safe alternatives to breastfeeding do not exist for most HIV-positive women. Provision of effective perinatal antiretroviral therapy, combined with safe alternative feeding methods, is required to significantly affect the extraordinary rate of HIV disease among children in the developing world.

Determinants of human immunodeficiency virus DNA and RNA shedding in the anal-rectal canal of homosexual men.

To define the determinants of anal-rectal shedding of human immunodeficiency virus (HIV) DNA and RNA, 374 HIV-seropositive homosexual men were tested. Factors independently associated with detection of anal-rectal HIV DNA included anal-rectal inflammation and detection of anal human papillomavirus DNA; predictors of HIV RNA included detection of anal-rectal HIV DNA, anal-rectal inflammation, and high plasma HIV RNA levels. The latter (>10,000 copies/mL) was the main determinant of anal-rectal HIV RNA shedding when HIV DNA (e.g., HIV-infected cells) was not detected in the anal-rectal sample. The local presence of HIV-infected cells and local inflammation were the principal determinants of HIV RNA among those with low (<10,000 copies/mL) plasma HIV RNA load. Among those with anal-rectal HIV DNA present, increased HIV RNA plasma load did not increase the risk of shedding of HIV RNA into the anal-rectal canal.

Detection of HIV DNA in cervical and vaginal secretions: Prevalence and correlates among women in Nairobi, Kenya

Objective. —Factors that influence heterosexual transmission of the human immunodeficiency virus (HIV), including sexually transmitted diseases, contraceptive practices, sexual practices, HIV-related immunosuppression, and presence of cervical ectopy and the penile foreskin, have been identified through cross-sectional and prospective cohort epidemiologic studies. To more directly characterize factors that influence infectivity, we conducted a study of HIV shedding from the genital tract in women. Design. —Ninety-seven HIV-seropositive women attending a sexually transmitted disease clinic in Nairobi, Kenya, completed a questionnaire and underwent a physical examination and an evaluation for sexually transmitted diseases. Cervical and vaginal secretions were obtained for HIV DNA detection using polymerase chain reaction amplification. Results. —Human immunodeficiency virus DNA was detected by polymerase chain reaction in 28 (33%) of 84 cervical samples and 13 (17%) of 77 vaginal samples. The prevalence of HIV was higher in specimens from the endocervix than from the vaginal wall (P=.002), and there was no correlation between presence of virus at the two sites. After adjusting for age, cervical HIV shedding was independently associated with oral contraceptive pill use (odds ratio [OR], 11.6; 95% confidence interval [CI], 1.7 to 77.6), cervical mucopus (OR, 6.2; 95% CI, 0.9 to 41.4;P=.05), cervical ectopy (OR, 5.0; 95% CI, 1.5 to 16.9), and pregnancy (OR, 4.5; 95% CI, 1.2 to 16.3). Conclusions. —Human immunodeficiency virus was detected in one third of cervical samples and one sixth of vaginal samples. The presence of HIV DNA in cervical secretions was significantly associated with oral contraceptive pill use, cervical ectopy, and pregnancy. There was a marginally significant association with cervical mucopus. The identification of factors that increase the infectivity of women suggests potential strategies for reducing heterosexual transmission of HIV. (JAMA. 1993;269:2860-2864)

Detection of HIV DNA in Cervical and Vaginal Secretions

Factors that influence heterosexual transmission of the human immunodeficiency virus (HIV), including sexually transmitted diseases, contraceptive practices, sexual practices, HIV-related immunosuppression, and presence of cervical ectopy and the penile foreskin, have been identified through cross-sectional and prospective cohort epidemiological studies. To more directly characterize factors that influence infectivity, we conducted a study of HIV shedding from the genital tract in women. Ninety-seven HIV-seropositive women attending a sexually transmitted disease clinic in Nairobi, Kenya, completed a questionnaire and underwent a physical examination and an evaluation for sexually transmitted diseases. Cervical and vaginal secretions were obtained for HIV DNA detection using polymerase chain reaction amplification. Human immunodeficiency virus DNA was detected by polymerase chain reaction in 28 (33%) of 84 cervical samples and 13 (17%) of 77 vaginal samples. The prevalence of HIV was higher in specimens from the endocervix than from the vaginal wall (P = .002), and there was no correlation between presence of virus at the two sites. After adjusting for age, cervical HIV shedding was independently associated with oral contraceptive pill use (odds ratio [OR], 11.6; 95% confidence interval [CI], 1.7 to 77.6), cervical mucopus (OR, 6.2; 95% CI, 0.9 to 41.4; P = .05), cervical ectopy (OR, 5.0; 95% CI, 1.5 to 16.9), and pregnancy (OR, 4.5; 95% CI, 1.2 to 16.3). Human immunodeficiency virus was detected in one third of cervical samples and one sixth of vaginal samples. The presence of HIV DNA in cervical secretions was significantly associated with oral contraceptive pill use, cervical ectopy, and pregnancy. There was a marginally significant association with cervical mucopus. The identification of factors that increase the infectivity of women suggests potential strategies for reducing heterosexual transmission of HIV.