Differential effects of sex in a West African cohort of HIV-1, HIV-2 and HIV-1/2 dually infected patients: men are worse off

Intrahost evolution of the HIV-2 capsid correlates with progression to AIDS

HIV-2 infection will progress to AIDS in most patients without treatment, albeit at approximately half the rate of HIV-1 infection. HIV-2 capsid (p26) amino acid polymorphisms are associated with lower viral loads and enhanced processing of T cell epitopes, which may lead to protective Gag-specific T cell responses common in slower progressors. Lower virus evolutionary rates, and positive selection on conserved residues in HIV-2 env have been associated with slower progression to AIDS. In this study we analysed 369 heterochronous HIV-2 p26 sequences from 12 participants with a median age of 30 years at enrolment. CD4% change over time was used to stratify participants into relative faster and slower progressor groups. We analysed p26 sequence diversity evolution, measured site-specific selection pressures and evolutionary rates, and determined if these evolutionary parameters were associated with progression status. Faster progressors had lower CD4% and faster CD4% decline rates. Median pairwise sequence diversity was higher in faster progressors (5.7x10-3 versus 1.4x10-3 base substitutions per site, P<0.001). p26 evolved under negative selection in both groups (dN/dS=0.12). Median virus evolutionary rates were higher in faster than slower progressors - synonymous rates: 4.6x10-3 vs. 2.3x10-3; and nonsynonymous rates: 6.9x10-4 vs. 2.7x10-4 substitutions/site/year, respectively. Virus evolutionary rates correlated negatively with CD4% change rates (ρ = -0.8, P=0.02), but not CD4% level. The signature amino acid at p26 positions 6, 12 and 119 differed between faster (6A, 12I, 119A) and slower (6G, 12V, 119P) progressors. These amino acid positions clustered near to the TRIM5α/p26 hexamer interface surface. p26 evolutionary rates were associated with progression to AIDS and were mostly driven by synonymous substitutions. Nonsynonymous evolutionary rates were an order of magnitude lower than synonymous rates, with limited amino acid sequence evolution over time within hosts. These results indicate HIV-2 p26 may be an attractive therapeutic target.

Food insecurity predicts loss to follow-up among people living with HIV in Senegal, West Africa

The goals of this study were to assess retention on antiretroviral therapy (ART) and to identify predictors of loss to follow-up (LTFU) among people living with HIV (PLHIV) in Senegal. HIV-positive individuals presenting for initiation of ART in Dakar and Ziguinchor were enrolled and followed for 12 months. Data were collected using interviews, clinical evaluations, laboratory analyses, chart review, and active patient tracing. Of the 207 individuals enrolled, 70% were female, 32% had no formal education, and 28% were severely food insecure. At the end of the follow-up period, 58% were retained on ART, 15% were deceased, 4% had transferred care, 5% had migrated, and 16% were lost to follow-up. Enrollment in Ziguinchor (OR 2.71 [1.01–7.22]) and severe food insecurity (OR 2.55 [1.09–5.96]) were predictive of LTFU. Sex, age, CD4 count, BMI <18.5, country of birth, marital status, number of children, household size, education, consultation with traditional healers, transportation time, and transportation cost were not associated with LTFU. The strongest predictor of severe food insecurity was lack of formal education (OR 2.75 [1.30–5.80]). Addressing the upstream drivers of food insecurity and implementing strategies to enhance food security for PLHIV may be effective approaches to reduce LTFU and strengthen the HIV care cascade in the region.

HIV treatment in Guinea-Bissau: room for improvement and time for new treatment options

Despite advances in the treatment quality of HIV throughout the world, several countries are still facing numerous obstacles in delivering HIV treatment at a sufficiently high quality, putting patients' lives in jeopardy. The aim of this status article is to give an overview of HIV treatment outcomes in the West African country, Guinea-Bissau, and to assess how newer treatment strategies such as long-acting injectable drugs or an HIV cure may limit or stop the HIV epidemic in this politically unstable and low-resource setting. Several HIV cohorts in Guinea-Bissau have been established and are used as platforms for epidemiological, virological, immunological and clinical studies often with a special focus on HIV-2, which is prevalent in the country. The Bandim Health Project, a demographic surveillance site, has performed epidemiological HIV surveys since 1987 among an urban population in the capital Bissau. The Police cohort, an occupational cohort of police officers, has enabled analyses of persons seroconverting with estimated times of seroconversion among HIV-1 and HIV-2-infected individuals, allowing incidence measurements while the Bissau HIV Cohort and a newer Nationwide HIV Cohort have provided clinical data on large numbers of HIV-infected patients. The HIV cohorts in Guinea-Bissau are unique platforms for research and represent real life in many African countries. Poor adherence, lack of HIV viral load measurements, inadequate laboratory facilities, high rates of loss to follow-up, mortality, treatment failure and resistance development, are just some of the challenges faced putting the goal of "90-90-90″ for Guinea-Bissau well out of reach by 2020. Maintaining undetectable viral loads on treatment as a prerequisite of a cure strategy seems not possible at the moment. Thinking beyond one-pill-once-a-day, long-acting antiretroviral treatment options such as injectable drugs or implants may be a better treatment option in settings like Guinea-Bissau and may even pave the way for an HIV cure. If the delivery of antiretroviral treatment in sub-Saharan Africa in a sustainable way for the future should be improved by focusing on existing treatment options or through focusing on new treatment options remains to be determined.

HIV-2 as a model to identify a functional HIV cure

Two HIV virus types exist: HIV-1 is pandemic and aggressive, whereas HIV-2 is confined mainly to West Africa and less pathogenic. Despite the fact that it has been almost 40 years since the discovery of AIDS, there is still no cure or vaccine against HIV. Consequently, the concepts of functional vaccines and cures that aim to limit HIV disease progression and spread by persistent control of viral replication without life-long treatment have been suggested as more feasible options to control the HIV pandemic. To identify virus-host mechanisms that could be targeted for functional cure development, researchers have focused on a small fraction of HIV-1 infected individuals that control their infection spontaneously, so-called elite controllers. However, these efforts have not been able to unravel the key mechanisms of the infection control. This is partly due to lack in statistical power since only 0.15% of HIV-1 infected individuals are natural elite controllers. The proportion of long-term viral control is larger in HIV-2 infection compared with HIV-1 infection. We therefore present the idea of using HIV-2 as a model for finding a functional cure against HIV. Understanding the key differences between HIV-1 and HIV-2 infections, and the cross-reactive effects in HIV-1/HIV-2 dual-infection could provide novel insights in developing functional HIV cures and vaccines.

HTLV prevalence is no longer following the decreasing HIV prevalence - 20 years of retroviral surveillance in Guinea-Bissau, West Africa

BACKGROUND

The HIV-2 and HTLV-1 prevalences in Bissau have followed similar trends in surveys from 1996 and 2006 with HTLV-1 prevalences of 3.6% and 2.3%, respectively. However, following the introduction of antiretroviral treatment (ART) and informative campaigns about HIV, the epidemics may have shifted. To evaluate the current HTLV prevalence and the continued association with HIV, we performed a third survey.

METHODS

A cross-sectional survey was performed from November 2014 to February 2016. In total, 2583 participants were interviewed, tested for HIV, and had blood samples collected. Samples were analysed for anti-HTLV using chemiluminescence and immunoblot assays. We calculated the HTLV prevalence for 2016 and examined risk factors for HTLV and associations with HIV using binominal regression.

RESULTS

The prevalence of HTLV was 2.8% (71/2583), 1.5% (16/1,089) for men and 3.7% (55/1,494) for women. Old age, female sex, HIV-2 infection and sharing a house with a HTLV- infected person were strong risk factors for HTLV. In contrast to previous studies, we found a non-significant increase in prevalence among the 15-24 year-olds since 2006, supporting ongoing transmission.

CONCLUSIONS

The HTLV prevalence in Bissau showed a non-significant increase. We found evidence supporting continuous vertical and horizontal routes of transmissions.

Delayed disease progression in HIV-2: the importance of TRIM5α and the retroviral capsid

HIV-2 is thought to have entered the human population in the 1930s through cross-species transmission of SIV from sooty mangabeys in West Africa. Unlike HIV-1, HIV-2 has not led to a global pandemic, and recent data suggest that HIV-2 prevalence is declining in some West African states where it was formerly endemic. Although many early isolates of HIV-2 were derived from patients presenting with AIDS-defining illnesses, it was noted that a much larger proportion of HIV-2-infected subjects behaved as long-term non-progressors (LTNP) than their HIV-1-infected counterparts. Many HIV-2-infected adults are asymptomatic, maintaining an undetectable viral load for over a decade. However, despite lower viral loads, HIV-2 progresses to clinical AIDS without therapeutic intervention in most patients. In addition, successful treatment with anti-retroviral therapy (ART) is more challenging than for HIV-1. HIV-2 is significantly more sensitive to restriction by host restriction factor tripartite motif TRIM5α than HIV-1, and this difference in sensitivity is linked to differences in capsid structure. In this review we discuss the determinants of HIV-2 disease progression and focus on the important interactions between TRIM5α and HIV-2 capsid in long-term viral control.

Long-term follow-up of HIV-2-related AIDS and mortality in Guinea-Bissau: a prospective open cohort study

BACKGROUND

HIV type 2 (HIV-2) is considered more benign and has fewer pathogenic consequences than HIV type 1 (HIV-1) for most infected individuals. However, reliable estimates of time to AIDS and mortality among those with HIV-2 infection are absent. We therefore aimed to compare the time to AIDS and mortality, and the CD4 T-cell dynamics between those infected with HIV-1 and HIV-2.

METHODS

We did a prospective open cohort study. We included all police officers with regular employment from police stations in both urban and rural areas of Guinea-Bissau since Feb 6, 1990. We continued to include participants until Sept 28, 2009, and follow-up of HIV-1-positive and HIV-2-positive individuals continued until Sept 28, 2013. We collected blood samples at enrolment and at scheduled annual follow-up visits at police stations. We analysed longitudinal data from individuals infected with HIV-1 and HIV-2 according to time to AIDS, time to death, and T-cell dynamics. Time of HIV infection was estimated as the mid-timepoint between last HIV-seronegative and first HIV-seropositive sample. Data from an additional 2984 HIV-uninfected individuals from the same population were analysed to assess the effect of natural mortality on HIV-related mortality.

FINDINGS

872 participants tested HIV positive during the 23-year study period: 408 were infected with HIV-1 (183 infected before and 225 infected after enrolment) and 464 were infected with HIV-2 (377 before and 87 after enrolment). The median time from HIV infection to development of AIDS was 6·2 years (95% CI 5·4-7·1) for HIV-1 infection and 14·3 years (10·7-18·0) for HIV-2 infection (p<0·0001). The median survival time after HIV infection was 8·2 years (95% CI 7·5-8·9) for HIV-1 infection and 15·6 years (12·0-19·2) for HIV-2 infection (p<0·0001). Individuals who were infected with HIV-1 or HIV-2 before enrolment showed similar results. Comparison with uninfected individuals indicated limited confounding contribution from natural mortality. Mean CD4 percentages were higher in individuals with HIV-2 than in those with HIV-1 during early infection (28·0% [SE 1·3] vs 22·3% [1·7]; p=0·00094) and declined at a slower rate (0·4% [0·2] vs 0·9% [0·2] per year; p=0·028). HIV-2-infected individuals developed clinical AIDS at higher mean CD4 percentages (18·2%, IQR 7·2-25·4) than HIV-1-infected individuals (8·2%, 3·0-13·8; p<0·0001).

INTERPRETATION

Our results show that both HIV-1-infected and HIV-2-infected individuals have a high probability of developing and dying from AIDS without antiretroviral treatment.

FUNDING

Swedish International Development Agency, Swedish Research Council, Swedish Society of Medical Research, Medical Faculty at Lund University, and Region Skåne Research and Development.

HIV-2 continues to decrease, whereas HIV-1 is stabilizing in Guinea-Bissau

OBJECTIVE

Although Guinea-Bissau has the world's highest prevalence of HIV-2, it has been decreasing since 1987. Meanwhile, the prevalence of HIV-1 has been increasing. We describe both the prevalence and changes in incidence of HIV-2 and HIV-1 during the last 30 years of observation in the capital Bissau in Guinea-Bissau.

METHODS

A total of 3125 adults living in 412 houses in Bissau were eligible for inclusion in the present cross-sectional survey conducted from November 2014 to February 2016. All participants had a questionnaire filled out and a blood sample taken. Results were compared with previous surveys.

RESULTS

Of the 3125 eligible adults, 2601 (83.2%) individuals participated. The overall prevalence of HIV decreased from 8.6% (218/2548) in 2006 to 6.7% (173/2601) in 2016 with an age-adjusted and sex-adjusted prevalence ratio (aPR) of 0.71 [95% confidence interval (CI) = 0.59-0.85]. Including HIV-1/2 dual infections, a decrease in the overall prevalence of HIV-2 from 4.4% (112/2548) to 2.8% (72/2601) was observed with an aPR of 0.55 (95% CI = 0.41-0.73). The overall prevalence of HIV-1 decreased from 4.6% (118/2548) to 4% (104/2601) with an aPR of 0.81 (95% CI = 0.63-1.05). Incidence rates for HIV-2 and HIV-1, estimated for 815 individuals, decreased from 0.24 to 0.09 and from 0.50 to 0.40 per 100 person-years of observation, respectively, in the periods between 1996-2006 and 2006-2016.

CONCLUSION

The prevalence of HIV-2 continues to decrease, whereas the prevalence of HIV-1 showed sign of stabilization. The results observed may be explained by a lower pathogenicity of HIV-2 and changes in risk behavior.

One-sixth of inpatients in a Danish infectious disease ward have imported diseases: A cross-sectional analysis

BACKGROUND

The aim of the study was to describe travel demographics and disease patterns of patients hospitalized with travel-related diseases, and assess risk factors to improve pre-travel information and post-travel diagnostics and treatment.

METHODS

The study included all patients hospitalized with travel-related diseases in 2015 at a Danish infectious diseases ward. Patient data was extracted from the in-patient hospital registry. was analyzed regarding diagnoses, destination, purpose of travel and pre-travel information.

RESULTS

240 patients were hospitalized with a total of 289 travel-related diseases, accounting for 16.6% (240/1450) of all admissions. Febrile illnesses were the most common (39.5%, 114/289) followed by respiratory (19.7%, 57/289) and gastrointestinal diagnoses (19.0%, 55/289). Most of the diseases were acquired in Sub-Saharan Africa (35.6%, 103/289) followed by South East Asia (27.0%, 78/289), and 60.0% (144/240) of the patients were tourists. One-third (36.3%, 81/223) of the non-migrants had received pre-travel information. The lowest rate was seen in people visiting friends and relatives (18.2%, 6/32).

CONCLUSION

Travel-related diseases are common among patients admitted to this Danish infectious disease ward. Malaria is the most common disease among both travelers and immigrants. In approximately one third of all the patients in our study etiology was unknown.

Effect of sex and age on outcomes among HIV-2-infected patients starting antiretroviral therapy in West Africa

OBJECTIVES

HIV-2-infected individuals usually initiate antiretroviral therapy (ART) at an advanced age compared with HIV-1 patients, with a potential impact on treatment outcomes. This study aimed to investigate the effect of sex and age on mortality and loss to follow-up (LTFU) among HIV-2-infected individuals initiating ART.

METHODS

Analyses were conducted using the database of the International Epidemiological Databases to Evaluate AIDS's collaboration in West Africa. LTFU was considered if the interval between the last visit and the closing date for this analysis was more than 180 days. Probability of death and LTFU were estimated with Kaplan-Meier methods. A Cox regression model was used to identify factors associated with death and LTFU over the first 24 months on ART.

RESULTS

A total of 1825 HIV-2-infected individuals, including 60% women were considered for this analysis. The median age, baseline CD4 cell count, and follow-up duration were 45 years [interquartile range (IQR; 38-52)], 185 cells/μl [IQR (95-297)], and 28.8 months [IQR (9.8-58.9)], respectively. Over the first 24 months, the mortality rate was 5.2/100 person-years of observation [95% confidence interval (CI; 4.4-6.1)] and 469 (25.7%) were LTFU. Male sex [hazard ratio (HR) = 1.9; 95% CI (1.4; 2.8)], baseline CD4 cell count less than 100 cell/μl [HR = 4.4 95% CI (1.7; 11.1); ref at least 350 cell/μl], haemoglobin 7.5-10 g/dl [HR = 2.4 95% CI (1.3; 4.4); ref at least 12 g/dl], and BMI less than 18 kg/m [HR = 2.1 95% CI (1.3; 3.4); ref = 18-25 kg/m] were associated with higher mortality over the first 24 months. Similar associations were found for LTFU.

CONCLUSION

Mortality and LTFU are high among ART-receiving HIV-2-infected individuals and higher in men than in women. There is a critical need to further determine the causes of poor retention and implement sex-specific solutions that improve outcomes in HIV-2 ART programmes.

High prevalence and excess mortality of late presenters among HIV-1, HIV-2 and HIV-1/2 dually infected patients in Guinea-Bissau - a cohort study from West Africa

Introduction

HIV infected individuals with late presentation (LP) and advanced disease (AD) have been associated with higher mortality, higher cost of medical management, impaired CD4 cell count increment and potentially ongoing risk of HIV transmission. Here we describe the proportion of patients with LP and AD at an HIV clinic in Guinea-Bissau, identify risk factors and evaluate the outcome of these patients.

Methods

We included all patients >15 years diagnosed with HIV-1 and/or HIV-2 at the outpatient HIV clinic at Hospital National Simão Mendes, during June 2005 - December 2013 in a retrospective cohort study. Patients were followed until December 2014. LP and AD was defined as a baseline CD4 cell count of 200-349 cells/µL and <200 cells/µL, respectively.

Results

A total of 3,720/5,562 (65.7%) patients had a CD4 cell count measured within the first 90 days of HIV diagnosis. Forty-eight percent had AD and 23% had LP. Risk factors for presentation with AD were male sex, age >30 years, Fula and Mandinga ethnicity. HIV-2 and HIV-1/2 dually infected patients had lower risk of AD compared with HIV-1 infected patients. Although antiretroviral therapy (ART) was initiated for 64.4% of patients, those with AD progression had a 3.82 times higher mortality compared to patients with non-LP.

Conclusion

The majority of HIV infected patients presented late. Most of the late-presenters had advanced disease and patients with advanced disease had a very high mortality. Initiatives to enroll patients in care at an earlier point are needed and should focus on risk groups.

Mortality and survival patterns of people living with HIV-2

PURPOSE OF REVIEW

People living with HIV-2 infected usually initiate antiretroviral therapy (ART) at an advanced period in the course of their infection after a long asymptomatic period characterized by high CD4 cell count and thus at a relatively advanced age. In the new international context of early and universal ART initiation, the aim was to review survival patterns among HIV-2 infected patients, either on ART or not.

RECENT FINDINGS

Very few reports were published on mortality in people living with HIV-2 during the last 5 years. People living with HIV-2 experience high mortality rates although lower than people living with HIV-1 before ART initiation. They seem to survive longer regardless of the conditions of ART use. Mortality is associated with late presentation, male sex, CD4 cell count less than 500 cell/μl, high plasma viral load, hemoglobin rate less than 8 g/dl and body mass index less than 18 kg/m.

SUMMARY

People living with HIV-2 initiate ART later than HIV-1 and HIV duals, resulting in higher disease progression and mortality rate. The clinical management of HIV-2 infected patients should now include early diagnosis and treatment initiation as per international guidelines. Further research needs to explore the 'what to start' question and document specific causes of death in people living with HIV-2 and enrolled in care in Africa.