1,683 research outputs found
Should HIV be a notifiable disease? Old questions with some new arguments
KMHIV notification enters national debate regularly, often introduced by politicians and supported by many individual healthcare workers. We argue that its proponents advance confused or poorly informed rationales for making HIV notifiable. We present reasons why making HIV notifiable would be inappropriate in South Africa, why the public health benefits of a notification programme are not even likely, and why there are risks of public health and human rights harms
Setting ART initiation targets in response to changing guidelines : The importance of addressing both steady-state and backlog
PKBackground: Target setting is useful in planning, assessing and improving antiretroviral treatment (ART) programmes. In the past 4 years, the ART initiation environment has been transformed due to the change in eligibility criteria (starting ART at a CD4+ count <350 cells/μl v. <200 cells/μl) and the roll-out of nurse-initiated management of ART.
Objective: To describe and illustrate the use of a target-setting model for estimating district-based targets in the era of an expanding ART programme and changing CD4+ count thresholds for ART initiation.
Method: Using previously described models and data for annual new HIV infections, we estimated both steady-state need for ART initiation and backlog in a North West Province district, accounting for the shift in eligibility. Comparison of actual v. targeted ART initiations was undertaken. The change in CD4+ count threshold adds a once-off group of newly eligible patients to the pool requiring ART – the backlog. The steady-state remains unchanged as it is determined by the annual rate of new HIV infections in previous years.
Results: The steady-state need for the district was 639 initiations/month, and the backlog was ~15 388 patients. After the shift in eligibility in September 2011, the steady-state target was exceeded over several months with some backlog addressed. Of the total backlog for this district, 72% remains to be cleared.
Conclusion: South Africa has two pools of patients who need ART: the steady-state of HIV-infected patients entering the programme each year, determined by historical infection rates; and the backlog created by the shift in eligibility. The healthcare system needs to build longterm capacity to meet the steady-state need for ART and additional capacity to address the backlog
Descriptive analysis of World Health Organization-recommended second-line antiretroviral treatment: A retrospective cohort data analysis
Background. World Health Organization guidelines recommend that HIV patients who do not achieve viral suppression on efavirenz-based first-line antiretroviral therapy (ART) should be changed to a protease inhibitor (PI)-based regimen. In South Africa (SA), ~200 000 people are on second-line treatment, but little is known about these patients.Objectives. To describe second-line black African patients in a large urban area.Methods. A quantitative retrospective study of 825 second-line patients in central Johannesburg, SA (subdistrict F), was performed with data extracted from government databases. Demographic characteristics, treatment status and laboratory information were gathered, then analysed with CD4+ cell count, viral load (VL) and retention-in-care data as outcome variables.Results. The average recorded time to VL measurement after the switch to a PI-based ART regimen was 20 months, and 83.1% (570/686) of patients with a recent VL achieved viral suppression while on second-line treatment. The most recent median CD4+ cell count for the cohort was 286 cells/µL (interquartile range 160 - 478), which represented a 177 cells/µL increase from the baseline count at the start of first-line ART. Slightly less than three-quarters (72.4%) of the population remained active in care in the study clinics from initiation on first-line ART. Demographic characteristics such as being <25 years of age, male sex and geographical transfer (started initial treatment in a different region) independently predicted low CD4+ cell counts and virological failure on second-line treatment. Patients with virological failure were most likely (odds ratio (OR) 3.13, 95% confidence interval (CI) 1.50 - 6.56) to be lost to follow-up after the switch, while patients from Hillbrow Community Health Centre (OR 0.27, 95% CI 0.16 - 0.44), South Rand Hospital (OR 0.24, 95% CI 0.12 - 0.47) and Jeppe Clinic (OR 0.38, 95% CI 0.16 - 0.88), three larger sites, were most likely to remain active in care.Conclusions. VL suppression was high in patients on second-line treatment, but one-fifth of patients were lost to follow-up. Younger age, male sex and transfer from other treatment sites predicted poor treatment outcomes, highlighting opportunities for prioritisation of adherence interventions.
Protease Inhibitor Resistance Is Uncommon in HIV-1 Subtype C Infected Patients on Failing Second-Line Lopinavir/r-Containing Antiretroviral Therapy in South Africa
Limited data exist on HIV-1 drug resistance patterns in South Africa following second-line protease-inhibitor containing regimen failure. This study examined drug resistance patterns emerging in 75 HIV-1 infected adults experiencing virologic failure on a second-line regimen containing 2 NRTI and lopinavir/ritonavir. Ninety six percent of patients (n = 72) were infected with HIV-1 subtype C, two patients were infected with HIV-1 subtype D and one with HIV-1 subtype A1. Thirty nine percent (n = 29) of patients had no resistance mutations in protease or reverse transcriptase suggesting that medication non-adherence was a major factor contributing to failure. Major lopinavir resistance mutations were infrequent (5 of 75; 7%), indicating that drug resistance is not the main barrier to future viral suppression
Cardiovascular toxicity of contemporary antiretroviral therapy
PURPOSE OF REVIEW: HIV treatment has evolved since the introduction of antiretroviral therapy (ART) in the 1990s. Earlier treatment strategies, and the introduction of integrase inhibitors in preferred first-line ART have fundamentally changed cardiovascular side effects due to HIV infection and ART. This review provides an update on cardiovascular toxicity of contemporary ART. RECENT FINDINGS: Cardiovascular disease (CVD) risk, including heart failure, is still increased in people living with HIV (PLWH). Exposure to older antiretrovirals, including stavudine and zidovudine, still impact on CVD risk through persistent changes in body fat distribution years after discontinuation. Protease inhibitors (PI) and efavirenz have associated metabolic disturbances and increased risk of CVD, although use is decreasing worldwide. Integrase inhibitors and CCR5 antagonists seem to have negligible immediate CVD toxicity. Weight gain on newer antiretrovirals including integrase inhibitors is a reason for concern. SUMMARY: CVD risk should be monitored carefully in PLWH who were exposed to first generation ART, efavirenz or to PIs. Registries should capture ART use and CVD events to stay informed on actual clinical risk in the current era of rapid initiation on integrase inhibitor-based ART
Gamma-rays from millisecond pulsars in Globular Clusters
Globular clusters (GCs) with their ages of the order of several billion years
contain many final products of evolution of stars such as: neutron stars, white
dwarfs and probably also black holes. These compact objects can be at present
responsible for the acceleration of particles to relativistic energies.
Therefore, gamma-ray emission is expected from GCs as a result of radiation
processes occurring either in the inner magnetosperes of millisecond pulsars or
in the vicinity of accreting neutron stars and white dwarfs or as a result of
interaction of particles leaving the compact objects with the strong radiation
field within the GC. Recently, GeV gamma-ray emission has been detected from
several GCs by the new satellite observatory Fermi. Also Cherenkov telescopes
reported interesting upper limits at the TeV energies which start to constrain
the content of GCs. We review the results of these gamma-ray observations in
the context of recent scenarios for their origin.Comment: 20 pages, 9 figures, will be published in Astrophysics and Space
Science Series (Springer), eds. N. Rea and D.F. Torre
Thermal limits of two biting midges, Culicoides imicola Kieffer and C. bolitinos Meiswinkel (Diptera: Ceratopogonidae)
BACKGROUND : Culicoides imicola Kieffer and Culicoides bolitinos Meiswinkel (Diptera: Ceratopogonidae) are both of
veterinary importance, being vectors of Schmallenberg, bluetongue and African horse sickness (AHS) viruses. Within
South Africa, these Culicoides species show a marked difference in their abundances according to altitude, with C.
imicola highly abundant in lower altitudes, but being replaced as the dominant species by C. bolitinos in cooler,
high-altitude regions.
METHODS : The thermal physiology of field collected adults of each species was determined to evaluate whether it
could account for differences in their distribution and abundance. Critical thermal maxima (CTmax) and minima
(CTmin), as well as upper and lower lethal temperatures (ULT and LLT) were assessed after acclimation temperatures
of 19°C, 24°C and 29°C. Critical thermal limits were determined using an ecologically relevant rate of temperature
change of 0.06°C.min−1.
RESULTS : Significant differences in CTmin and CTmax were found between acclimation temperatures for C. imicola
and C. bolitinos. In C. bolitinos, the LLT of individuals acclimated at 24°C was significantly improved (LLT50 = −6.01°C)
compared with those acclimated at the other temperatures (LLT50 = −4°C). Acclimation had a weak (difference in
LLT50 of only 1°C) but significant effect on the LLT of C. imicola. When CTmin, CTmax, LLT and ULT were
superimposed on daily maximum and minimum temperature records from locations where each tested Culicoides
species is dominant, it was found that temperatures frequently declined below the CTmin and LLT of C. imicola at
the location where C. bolitinos was dominant.
CONCLUSIONS : The distribution and abundance of C. imicola is likely directly constrained by their relatively poor
tolerance of lower temperatures. Results for C. bolitinos suggest that the adult phase is hardy, and it is hypothesised
that the thermal biology of other life stages could determine their range.http://www.parasite-journal.org/hb201
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