87 research outputs found
Enhancing capacity of research ethics review committees in developing countries: The Kenyan example
Background. The increased number of clinical trials taking place in developing countries and the complexity of trial protocols mandate thatlocal ethics review committees (ERCs) reviewing them have the capacity to ensure that they are conducted to the highest ethical standards.Methods. The Kenya AIDS Vaccine Initiative (KAVI) Institute of Clinical Research (ICR) (KAVI-ICR) and the Kenyan National Council for Scienceand Technology (NCST) embarked on an exercise to enhance the capacity of ERCs in Kenya to review such protocols. This process involved conducting an audit of all ERCs in the country, and performing training needs assessments to identify knowledge and capacity gaps. Information obtained was used to develop training materials for ERC members at workshops conducted in different parts of the country.Results. Five accredited and 13 non-accredited ERCs were identified. Four of the accredited ERCs were located in the capital city of Kenya, Nairobi. The most common challenges cited by participants during the needs assessments were excess workload, and a lack of co-ordination and/or communication between the ERCs. Subsequently, 140 ERC members from 17 institutions across the country were trained as follows: 36 from institutions in the western part of Kenya, 38 from institutions in the south-eastern coastal region, 38 from the eastern region and 44 from Nairobi.Conclusion. The KAVI-ICR and the NCST have developed training modules for training ERC members in Kenya and are in the process of developing a manual to train members. The Kenyan experience may be used to enhance the capacity of ERCs in the East African region
Serologic testing algorithm for recent HIV seroconversion in estimating incidence of HIV-1 among adults visiting a VCT centre at a Kenyan tertiary health institution
Objective: To determine HIV high risk groups among adults visiting Kenyatta National Hospital Voluntary Counselling and Testing Centre by use of Serologic Testing Algorithm for Recent HIV Seroconversion (STARHS).Design: A cross-sectional study of adults.Setting: Kenyatta National Hospital Voluntary and Counselling Centre.Results: Of the 6,415 adults screened for antibodies to HIV at Kenyatta National Hospital VCT Centre between July 2002 and February 2003, 728 tested positive in the two HIV screening tests used at the center, indicating a prevalence of 11%. Of these seropositive cases, 355 consented to participate in the study. Using STARHS, 34 (9.6%) of the plasma samples were classified as being from individuals with recent infection (within 170 days), giving an annual estimated HIV-1 incidence in this population of 1.3 infections per 100 person-years with a 95% CI of 0.872–1.728%. Young adults had a higher rate of new infection than older adults. Young females were infected much earlier in life, with a peak age of new infections of 26 years, versus. 31 years for young males.Conclusion: This study confirms our hypothesis that STARHS or Detuned assay can be used to determine HIV incidence in this population. The HIV high risk groups as identified by this study are young women between ages 16 to 26 years old and men between ages 45 to 55 years of age
Canine distemper virus neutralization activity is low in human serum and it is sensitive to an amino acid substitution in the hemagglutinin protein
© 2015 Elsevier Inc.Serum was analyzed from 146 healthy adult volunteers in eastern Africa to evaluate measles virus (MV) and canine distemper virus (CDV) neutralizing antibody (nAb) prevalence and potency. MV plaque reduction neutralization test (PRNT) results indicated that all sera were positive for MV nAbs. Furthermore, the 50% neutralizing dose (ND50) for the majority of sera corresponded to antibody titers induced by MV vaccination. CDV nAbs titers were low and generally were detected in sera with high MV nAb titers. A mutant CDV was generated that was less sensitive to neutralization by human serum. The mutant virus genome had 10 nucleotide substitutions, which coded for single amino acid substitutions in the fusion (F) and hemagglutinin (H) glycoproteins and two substitutions in the large polymerase (L) protein. The H substitution occurred in a conserved region involved in receptor interactions among morbilliviruses, implying that this region is a target for cross-reactive neutralizing antibodies
Host genetics and viral load in primary HIV-1 infection: clear evidence for gene by sex interactions
© 2014, The Author(s).Research in the past two decades has generated unequivocal evidence that host genetic variations substantially account for the heterogeneous outcomes following human immunodeficiency virus type 1 (HIV-1) infection. In particular, genes encoding human leukocyte antigens (HLA) have various alleles, haplotypes, or specific motifs that can dictate the set-point (a relatively steady state) of plasma viral load (VL), although rapid viral evolution driven by innate and acquired immune responses can obscure the long-term relationships between HLA genotypes and HIV-1-related outcomes. In our analyses of VL data from 521 recent HIV-1 seroconverters enrolled from eastern and southern Africa, HLA-A*03:01 was strongly and persistently associated with low VL in women (frequency = 11.3 %, P 0.50). In a reduced multivariable model, age, sex, geography (clinical sites), previously identified HLA factors (HLA-B*18, B*45, B*53, and B*57), and the interaction term for female sex and HLA-A*03:01 collectively explained 17.0 % of the overall variance in geometric mean VL over a 3-year follow-up period (P < 0.0001). Multiple sensitivity analyses of longitudinal and cross-sectional VL data yielded consistent results. These findings can serve as a proof of principle that the gap of “missing heritability” in quantitative genetics can be partially bridged by a systematic evaluation of sex-specific associations
Sensitivity And Specificity Of Hiv Rapid Tests Used For Research And Voluntary Counselling And Testing
Background: HIV rapid tests (RT) are a quick and non-technically demanding means to perform HIV voluntary counselling and testing (VCT) but understanding their
limitations is vital to delivering quality VCT.
Objective: To determine the sensitivity and specificity of HIV rapid tests used for
research and voluntary counselling and testing at four sites in East Africa.
Design: Cross-sectional study.
Setting: Masaka District, Uganda; a sugar plantation in Kakira, Uganda; Coastal
Villages in the Kilifi District of Kenya; and the Urban slum of Kangemi located West
of Nairobi, Kenya.
Subjects: Six thousands two hundred and fifty five consenting volunteers were enrolled
into the study, and 675 prevalent HIV infections were identified.
Results: The RT sensitivity tended to be high for all assays at all sites (97.63-100%) with
the exception of the Uni-Gold assay (90.24% in Kangemi, 96.58% in Kilifi). Twenty
four RT results were recorded as ‘weak positives\', 22 (92%) of which were negative
by ELISA. There was a high rate of RT false positives in Uganda (positive predictive
values ranging from 45.70% to 86.62%).
Conclusions: The sensitivity and specificity of the RT varied significantly across sites.
The rate of RT misclassification in Uganda suggests that a multiple test algorithm may
be preferable to a single test as screener for HIV VCT. East African Medical Journal Vol. 85 (10) 2008: pp. 500-50
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Keloids: Does patients’ sex influence the presentation and recurrence post-excision?
LIGHT AND ELECTRON MICROSCOPIC STUDY OF SURFACES OF TEST-SPECIMENS TESTED IN WEAR APPARATUSES
Objective: Symptoms of acute retroviral syndrome (ARS) may be used to identify patients with acute HIV-1 infection who seek care. ARS symptoms in African adults differ by region. We assessed whether reporting of ARS was associated with HIV-1 subtype in a multicentre African cohort study representing countries with predominant HIV-1 subtypes A, C, and D. Methods: ARS symptoms were assessed in adults enrolling within 6 weeks after the estimated date of infection in an acute and early HIV-1 infection cohort study. HIV-1 subtype was determined by POL genotyping. We used log-binomial regression to compare ARS symptom prevalence among those with subtype A vs. C or D, adjusting for sex, time since enrolment, and enrolment viral load. Results: Among 183 volunteers ascertained within 6 weeks after estimated date of infection, 77 (42.0%) had subtype A, 83 (45.4%) subtype C, and 23 (12.6%) subtype D infection. Individuals with subtype A were 1.40 (95% confidence interval: 1.17, 1.68) times as likely as individuals with subtypes C or D to report any ARS symptoms; each individual symptom other than rash was also more prevalent in subtype A than in subtype C or D, with prevalence ratios ranging from 1.94 (1.40, 2.70) for headache to 4.92 (2.24, 10.78) for lymphadenopathy. Conclusion: Individuals with subtype A were significantly more likely than individuals with subtypes C or D to report any ARS symptoms. HIV-1 subtypes may help explain differences in ARS that have been observed across regions in Africa, and may impact the yield of symptom-based screening strategies for acute HIV infection detection
Pregnancy rates among female participants in phase 1 and phase 2A AIDS vaccine clinical trials in Kenya
Background: Female participants in AIDS candidate vaccine clinical trials must agree to use effective contraception to be enrolled into the studies, and for a specified period after vaccination, since the candidate vaccines’ effects on the embryo or foetus are unknown.Objectives: To review data on female participants’ pregnancy rates from phase I and IIA AIDS vaccine clinical trials conducted at the Kenya AIDS Vaccine Initiative (KAVI) and to discuss the challenges of contraception among female participants.Design: Descriptive observational retrospective study.Setting: KAVI clinical trial site, Kenyatta National Hospital and University of Nairobi, Kenya.Subjects: Thirty nine female participants were enrolled into these trials. They received family planning counselling and were offered a choice of different contraceptive methods, as per the protocols. All contraception methods chosen by the participants were offered at the study site at no cost to the participant.Results: Four women conceived during the study period when pregnancies were to be avoided. All four had opted for sexual abstinence as a contraceptive method, but reported having been coerced by their partners to have unprotected sexual intercourse.Conclusion: Abstinence is clearly not a reliable contraceptive option for women in developing-country settings. Effective female-controlled contraceptives, administered at the clinical trial site, may empower female participants to better control their fertility, leading to more complete clinical trial data
P06-08. Building an African HIV preventive trial network
Africa is a crucial setting for preventive HIV clinical trials. We present our experience of setting up a collaborative network of African clinical research centers (CRC)
A Phase I Double Blind, Placebo-Controlled, Randomized Study of the Safety and Immunogenicity of Electroporated HIV DNA with or without Interleukin 12 in Prime-Boost Combinations with an Ad35 HIV Vaccine in Healthy HIV-Seronegative African Adults.
Strategies to enhance the immunogenicity of DNA vaccines in humans include i) co-administration of molecular adjuvants, ii) intramuscular administration followed by in vivo electroporation (IM/EP) and/or iii) boosting with a different vaccine. Combining these strategies provided protection of macaques challenged with SIV; this clinical trial was designed to mimic the vaccine regimen in the SIV study.Seventy five healthy, HIV-seronegative adults were enrolled into a phase 1, randomized, double-blind, placebo-controlled trial. Multi-antigenic HIV (HIVMAG) plasmid DNA (pDNA) vaccine alone or co-administered with pDNA encoding human Interleukin 12 (IL-12) (GENEVAX IL-12) given by IM/EP using the TriGrid Delivery System was tested in different prime-boost regimens with recombinant Ad35 HIV vaccine given IM.All local reactions but one were mild or moderate. Systemic reactions and unsolicited adverse events including laboratory abnormalities did not differ between vaccine and placebo recipients. No serious adverse events (SAEs) were reported. T cell and antibody response rates after HIVMAG (x3) prime-Ad35 (x1) boost were independent of IL-12, while the magnitude of interferon gamma (IFN-γ) ELISPOT responses was highest after HIVMAG (x3) without IL-12. The quality and phenotype of T cell responses shown by intracellular cytokine staining (ICS) were similar between groups. Inhibition of HIV replication by autologous T cells was demonstrated after HIVMAG (x3) prime and was boosted after Ad35. HIV specific antibodies were detected only after Ad35 boost, although there was a priming effect with 3 doses of HIVMAG with or without IL-12. No anti-IL-12 antibodies were detected.The vaccines were safe, well tolerated and moderately immunogenic. Repeated administration IM/EP was well accepted. An adjuvant effect of co-administered plasmid IL-12 was not detected.ClinicalTrials.gov NCT01496989
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