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1.
Artigo em Inglês | MEDLINE | ID: mdl-38770792

RESUMO

Mother-to-child transmission (MTCT) of HIV-1 and associated mortality continue to occur at unacceptably high rates, despite the extensive rollout and implementation of Prevention of Mother-to-Child Transmission (PMTCT) Programs, including the modified versions of Option B and B+ in 2010 and 2012, respectively. Maternal HIV viral load (VL) and socio-behavioral factors sustaining MTCT in Rwanda remain largely unexplored. The study examined the effects of socio-behavioral factors on maternal VL and their contribution to in utero transmission of HIV-1 in the context of Rwanda's HIV epidemic. A prospective cohort study was conducted in 862 mother-baby pairs enrolled in 10 PMTCT clinics in Rwanda. VL was determined on plasma and Dried Blood Spots samples, whereas HIV DNA PCR was performed to determine in utero MTCT of HIV of the babies immediately at birth and then at 3 weeks, 4 weeks, 6 months, and 18 months, together with HIV antibody testing to determine other forms of MTCT of HIV. Quantitative data on socio-behavioral factors were collected through a structured questionnaire. Linear regression and univariate analysis of variances using SPSS 25.0 were used to test the hypotheses. We found 22/862 (2.55%) cases of in utero transmission and a total of 32/862 (3.7%) cases of MTCT of HIV-1 over 18 study months. Maternal VL at delivery was significantly associated with the risk of in utero transmission of HIV-1. Socio-behavioral factors associated with elevated maternal VL at delivery included alcohol, smoking, multiple sexual partners, mothers' income, being a casual laborer, and distance to health care services. We report an MTCT rate of 3.7% in our study population over the 18 months, higher than the national average of 1.5%, the majority of which occurred in utero. MTCT cases were attributable to failure to suppress maternal VL.

2.
Sci Rep ; 13(1): 22182, 2023 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-38092870

RESUMO

Childhood HBV immunization remains globally fundamental to the elimination of hepatitis B virus (HBV). However, monitoring proportions of HBV vaccine seroprotection and their determinants among African Pediatric recipients is crucial. This study sought to verify extent of immune protection accorded by the HBV vaccine in African children of up to 17 years of age by pooling the prevalence of seroprotection reported by primary studies conducted in the Northern, Western, and Southern African regions. We included 19 eligible articles out of the 197 initially downloaded, published from 1999 to 2021 from African Journals Online (AJOL), EMBASE, Scopus, and PubMed. The study protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO), University of York Centre for Reviews and Dissemination, under the registration number CRD42022361277. Significantly higher (p < 0.0001) proportion of HBV vaccine seroprotection (69.07%) was found among children under 15 years of age than children 15-17 years (32.368%), 95% CI [34.2454-39.0847%]. Whereas successful integration of the HBV vaccine on the extended programs on immunizations (EPI) has been a major achievement in the reduction of HBV infection in Africa, markedly reduced HBV vaccine seroprotection is persistently demonstrated among adolescent children 15-17 years of age. Future studies are required to clarify the need for booster dose vaccination in most at risk populations and age groups.


Assuntos
Vacinas contra Hepatite B , Hepatite B , Adolescente , Criança , Humanos , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Anticorpos Anti-Hepatite B , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B
3.
BMJ Paediatr Open ; 7(1)2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37532465

RESUMO

BACKGROUND: Neonatal mortality due to tetanus persists in Uganda despite the mandatory vaccination of pregnant mothers. Maternal antibodies wane within a year. Uganda's maternal vaccination guidelines do not specify the timing or frequency of tetanus shots, contributing to suboptimal transfer of tetanus antibodies to neonates. We aimed to determine the prevalence and factors associated with protective tetanus antibodies among newborns at Kawempe National Referral Hospital. METHODS: We conducted a cross-sectional study among 293 mother-newborn pairs. At delivery, neonatal cord and maternal venous blood were collected and titred for antitetanus antibodies using a quantitative ELISA kit. The primary outcome of the study was the proportion of newborn babies with tetanus antibodies ≥0.1 IU/mL. Associated factors were determined using generalised linear models for the Poisson family with a log link and robust variance estimation. RESULTS: A total of 258/293 (88.1%) newborns had protective antibody titres. Factors associated with adequate protective antibodies in the newborn included: high (≥0.1 IU/mL) maternal antibody titres, first antenatal visit ≥12 weeks of gestation and receiving a tetanus toxoid (TT) shot ≥28 weeks of gestation. However, number of doses received before current pregnancy was not associated with adequate protective antibody titres. CONCLUSION: There is a high prevalence of adequate protective levels of antibodies among TT-vaccinated mothers. Maternal titres and a third trimester TT dose correlate with adequate levels of protective anti-TT antibodies among newborns. A third trimester TT dose is recommended.


Assuntos
Mães , Tétano , Gravidez , Lactente , Recém-Nascido , Humanos , Feminino , Tétano/prevenção & controle , Toxoide Tetânico , Toxoides , Uganda/epidemiologia , Estudos Transversais
4.
PLOS Glob Public Health ; 3(8): e0001566, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37585383

RESUMO

The estimated mortality rate of the SARS-CoV-2 pandemic varied greatly around the world. In particular, multiple countries in East, Central, and West Africa had significantly lower rates of COVID-19 related fatalities than many resource-rich nations with significantly earlier wide-spread access to life-saving vaccines. One possible reason for this lower mortality could be the presence of pre-existing cross-reactive immunological responses in these areas of the world. To explore this hypothesis, an exploratory study of stored peripheral blood mononuclear cells (PBMC) from Ugandans collected from 2015-2017 prior to the COVID-19 pandemic (n = 29) and from hospitalized Ugandan COVID-19 patients (n = 3) were examined using flow-cytometry for the presence of pre-existing SARS-CoV-2 cross-reactive CD4+ and CD8+ T-cell populations using four T-cell epitope mega pools. Of pre-pandemic participants, 89.7% (26/29) had either CD4+ or CD8+, or both, SARS-CoV-2 specific T-cell responses. Specifically, CD4+ T-cell reactivity (72.4%) and CD8+ T-cell reactivity (65.5%) were relatively similar, and 13 participants (44.8%) had both types of cross-reactive types of T-cells present. There were no significant differences in response by sex in the population, however this may be in part due to the limited sample size examined. The rates of cross-reactive T-cell populations in this exploratory Ugandan population appears higher than previous estimates from resource-rich countries like the United States (20-50% reactivity). It is unclear what role, if any, this cross-reactivity played in decreasing COVID-19 related mortality in Uganda and other African countries, but does suggest that a better understanding of global pre-existing immunological cross-reactivity could be an informative data of epidemiological intelligence moving forward.

5.
medRxiv ; 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36711579

RESUMO

The estimated mortality rate of the SARS-CoV-2 pandemic varied greatly around the world with multiple countries in East, Central, and West Africa having significantly lower rates of COVID-19 related fatalities than many resource-rich nations with significantly earlier wide-spread access to life-saving vaccines. One possible reason for this lower mortality could be the presence of pre-existing cross-reactive immunological responses in these areas of the world. To explore this hypothesis, stored peripheral blood mononuclear cells (PBMC) from Ugandans collected from 2015-2017 prior to the COVID-19 pandemic (n=29) and from hospitalized Ugandan COVID-19 patients (n=3) were examined using flow-cytometry for the presence of pre-existing SARS-CoV-2 cross-reactive CD4+ and CD8+ T-cell populations using four T-cell epitope mega pools. Of pre-pandemic participants, 89.7% (26/29) had either CD4+ or CD8+, or both, SARS-CoV-2 specific T-cell responses. Specifically, CD4+ T-cell reactivity (72.4%) and CD8+ T-cell reactivity (65.5%) were relatively similar, and 13 participants (44.8%) had both types of cross-reactive types of T-cells present. There were no significant differences in response by sex in the population. The rates of cross-reactive T-cell populations in these Ugandans is higher than previous estimates from resource-rich countries like the United States (20-50% reactivity). It is unclear what role, if any, this cross-reactivity played in decreasing COVID-19 related mortality in Uganda and other African countries, but does suggest that a better understanding of global pre-existing immunological cross-reactivity could be an informative data of epidemiological intelligence moving forward.

6.
F1000Res ; 10: 598, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34457243

RESUMO

Background: In January 2020, a previously unknown coronavirus strain was identified as the cause of a severe acute respiratory syndrome (SARS-CoV-2). The first viral whole-genome was sequenced using high-throughput sequencing from a sample collected in Wuhan, China. Whole-genome sequencing (WGS) is imperative in investigating disease outbreak transmission dynamics and guiding decision-making in public health. Methods: We retrieved archived SARS-CoV-2 samples at the Integrated Biorepository of H3Africa Uganda, Makerere University (IBRH3AU). These samples were collected previously from individuals diagnosed with coronavirus disease 2019 (COVID-19) using real-time reverse transcription quantitative polymerase chain reaction (RT-qPCR). 30 samples with cycle thresholds (Cts) values <25 were selected for WGS using SARS-CoV-2 ARTIC protocol at Makerere University Molecular Diagnostics Laboratory. Results: 28 out of 30 (93.3%) samples generated analyzable genomic sequence reads. We detected SARS-CoV-2 and lineages A (22/28) and B (6/28) from the samples. We further show phylogenetic relatedness of these isolates alongside other 328 Uganda (lineage A = 222, lineage B = 106) SARS-CoV-2 genomes available in GISAID by April 22, 2021 and submitted by the Uganda Virus Research Institute. Conclusions: Our study demonstrated adoption and optimization of the low-cost ARTIC SARS-CoV-2 WGS protocol in a resource limited laboratory setting. This work has set a foundation to enable rapid expansion of SARS-CoV-2 WGS in Uganda as part of the Presidential Scientific Initiative on Epidemics (PRESIDE) CoV-bank project and IBRH3AU.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Filogenia , Uganda/epidemiologia , Sequenciamento Completo do Genoma
7.
PLoS One ; 16(5): e0251150, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33983997

RESUMO

INTRODUCTION: Despite the limited evidence for its effectiveness, thermal screening at points of entry has increasingly become a standard protocol in numerous parts of the globe in response to the COVID-19 pandemic. We sought to determine the effectiveness of thermal screening as a key step in diagnosing COVID-19 in a resource-limited setting. MATERIALS AND METHODS: This was a retrospective cross-sectional study based on a review of body temperature and Xpert Xpress SARS CoV-2 test results records for truck drivers entering Uganda through Mutukula between 15th May and 30th July 2020. All records missing information for body temperature, age, gender, and Xpert Xpress SARS CoV-2 status were excluded from the data set. A data set of 7,181 entries was used to compare thermal screening and Xpert Xpress SARS CoV-2 assay test results using the diagnostic statistical test in STATAv15 software. The prevalence of COVID-19 amongst the truck drivers based on Xpert Xpress SARS CoV-2 assay results was determined. The sensitivity, specificity, positive predictive value, negative predictive value, positive and negative Likelihood ratios were obtained using Xpert Xpress SARS CoV-2 assay as the gold standard. RESULTS: Based on our gold standard test, the proportion of persons that tested positive for COVID-19 was 6.7% (95% CI: 6.1-7.3). Of the 7,181 persons that were thermally screened, 6,844 (95.3%) were male. The sample median age was 38 years (interquartile range, IQR: 31-45 years). The median body temperature was 36.5°C (IQR: 36.3-36.7) and only n (1.2%) had a body temperature above 37.5°C. The sensitivity and specificity of thermal screening were 9.9% (95% CI: 7.4-13.0) and 99.5% (95% CI: 99.3-99.6) respectively. The positive and negative predictive values were 57.8 (95% CI: 46.5-68.6) and 93.9 (95% CI: 93.3-94.4) respectively. The positive and negative Likelihood Ratios (LRs) were 19 (95% CI: 12.4-29.1) and 0.9 (95% CI: 0.88-0.93) respectively. CONCLUSION: In this study population, the use of Thermal screening alone is ineffective in the detection of potential COVID-19 cases at point of entry. We recommend a combination of screening tests or additional testing using highly sensitive molecular diagnostics such as Polymerase Chain Reaction.


Assuntos
COVID-19/diagnóstico , Adulto , Temperatura Corporal , Estudos Transversais , Feminino , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , SARS-CoV-2/isolamento & purificação , Uganda/epidemiologia , Adulto Jovem
8.
Pan Afr Med J ; 37: 208, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33505576

RESUMO

INTRODUCTION: fishing communities in Uganda are key populations for HIV, with persistently higher prevalence and incidence than the general population. METHODS: between March and August 2014, a cross sectional survey was conducted in 10 fishing communities of Lake Victoria in Uganda. Data was collected on socio-behavioural characteristics using interviewer administered questionnaires and venous blood collected for HIV testing. Prevalent HIV infections among adolescents and young people aged 13 to 24 years was estimated and the factors associated with those infections determined using multi variable logistic regression modelling. RESULTS: HIV prevalence was 10.8% among the 630 (96.5%) who provided a blood sample. Females were 3.5 times as likely to have HIV infection as males (aOR=3.52, 95% CI: 1.34-9.22). Young people aged 20-24 years were twice as likely to be HIV infected as those aged 13-19 years (aOR=1.77, 95% CI: 0.05-2.10), participants without formal education or those who had studied up to primary level were more likely to be HIV infected than those who had post primary education ((aOR=2.45, 95% CI: 1.19-5.07) or (5.29 (1.35-20.71) respectively). Reporting more than one sexual partner in the past 6 months was associated with HIV prevalent infection than those reporting no sexual partners (aOR=6.44, 95% CI: 1.27-32.83). CONCLUSION: adolescents and young people aged 13-24 years in fishing communities around Lake Victoria, Uganda, have a high HIV prevalence, with females having a three-fold higher level than males. These findings highlight-the need to improve HIV prevention among young females living in these fishing communities.


Assuntos
Infecções por HIV/epidemiologia , Comportamento Sexual/estatística & dados numéricos , Parceiros Sexuais , Adolescente , Estudos Transversais , Escolaridade , Feminino , Humanos , Masculino , Prevalência , Distribuição por Sexo , Inquéritos e Questionários , Uganda/epidemiologia , Adulto Jovem
9.
AIDS Res Hum Retroviruses ; 35(4): 382-387, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30560683

RESUMO

Uganda is among the most HIV/AIDS-afflicted countries, and many HIV-infected persons live in remote areas with poor access to health care. The success of HIV care programs relies in part on patient monitoring using CD4 T cell counts. We conducted an evaluation of the point-of-care PIMA test using BD FACSCount as a gold standard. One hundred fifty-one participants were enrolled, provided venous blood and samples tested at the point of care with the Alere PIMA™ CD4 Analyzer and the BD FACSCount in the UVRI-IAVI main laboratory. Correlation between the methods was assessed, as was the ability of the Pima Analyzer to predict values <200, <350, and ≥500 CD4 cells/mm3 when compared with BD FACSCount as the gold standard. A near-perfect positive Pearson correlation coefficient (r = 0.948; p < .0001) between the two methods was observed. The Alere PIMA Analyzer had a mean bias of -32.5 cells/mm3. The sensitivity and specificity, for PIMA to predict CD4 lymphocyte count less than 200 cells/mm3, were 71.4% and 100%, respectively; less than 350 cells/mm3 were 84.6% and 94.6%, respectively; and at CD4 count less than 500 cells/mm3 were 94.4% and 100%. The Alere Pima Analyzer provides reliable CD4 cell count measurement and is suitable for monitoring and screening eligible HIV patients in hard-to-reach settings.


Assuntos
Contagem de Linfócito CD4/métodos , Aconselhamento , Infecções por HIV/diagnóstico , Programas de Rastreamento/métodos , Sistemas Automatizados de Assistência Junto ao Leito/normas , Adulto , Contagem de Linfócito CD4/instrumentação , Contagem de Linfócito CD4/normas , Feminino , Citometria de Fluxo , Humanos , Lagos , Masculino , Programas de Rastreamento/instrumentação , Unidades Móveis de Saúde , População Rural , Sensibilidade e Especificidade , Uganda
10.
PLoS One ; 12(2): e0171200, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28207844

RESUMO

BACKGROUND: Although the association between alcohol consumption and HIV risk is well documented, few studies have examined the magnitude of new HIV infections that could be prevented by controlling alcohol use. We report the population attributable fraction (PAF) of incident HIV infections due to alcohol consumption among the HIV high-risk population of fishing communities along Lake Victoria, Uganda. METHODS: In a community-based cohort study, 1607 HIV sero-negative participants aged 18-49 years were enrolled from eight fishing communities along Lake Victoria, Uganda. At follow up 12 months later, 1288 (80.1%) were seen and interviewed. At baseline and follow-up visits, participants completed interviewer-administered questionnaires on alcohol consumption, demographics, and sexual risk behavior, and were tested for HIV infection. HIV incidence and adjusted incident rate ratios (adjusted IRRs) were estimated using Poisson regression models; the crude and adjusted PAFs of incident HIV infections associated with alcohol consumption were calculated using the Greenland and Drescher method for cohort studies. RESULTS: Among the 1288 participants seen at follow up, 53.5% reported drinking alcohol of whom 24.4% drank occasionally (2 days a week or less) and 29.1% drank regularly (3-7 days a week). Forty eight incident HIV infections occurred giving an incidence rate of 3.39/100 person years at-risk (pyar) (95% CI, 2.55-4.49). Compared to non-drinkers, the adjusted IRR of HIV was 3.09 (1.13-8.46) among occasional drinkers and 5.34 (2.04-13.97) among regular drinkers. The overall adjusted PAF of incident HIV infections due alcohol was 64.1 (95% CI; 23.5-83.1); ranging from 52.3 (11.9-74.2) among Muslims to 71.2 (32.6-87.7) for participants who reported ≥ 2 sexual partners in the past 12 months. CONCLUSION: In fishing communities along Lake Victoria, Uganda, 64% of new HIV infections can be attributed to drinking alcohol. Interventions to reduce alcohol consumption should be integrated in HIV/AIDS prevention activities for populations in whom both HIV and alcohol consumption are highly prevalent.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Pesqueiros , Infecções por HIV/epidemiologia , HIV-1/patogenicidade , Adolescente , Adulto , Feminino , Infecções por HIV/virologia , Humanos , Incidência , Lagos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Assunção de Riscos , Uganda/epidemiologia , Adulto Jovem
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