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1.
N Engl J Med ; 389(8): 722-732, 2023 Aug 24.
Article in English | MEDLINE | ID: mdl-37611122

ABSTRACT

BACKGROUND: Partial resistance of Plasmodium falciparum to the artemisinin component of artemisinin-based combination therapies, the most important malaria drugs, emerged in Southeast Asia and now threatens East Africa. Partial resistance, which manifests as delayed clearance after therapy, is mediated principally by mutations in the kelch protein K13 (PfK13). Limited longitudinal data are available on the emergence and spread of artemisinin resistance in Africa. METHODS: We performed annual surveillance among patients who presented with uncomplicated malaria at 10 to 16 sites across Uganda from 2016 through 2022. We sequenced the gene encoding kelch 13 (pfk13) and analyzed relatedness using molecular methods. We assessed malaria metrics longitudinally in eight Ugandan districts from 2014 through 2021. RESULTS: By 2021-2022, the prevalence of parasites with validated or candidate resistance markers reached more than 20% in 11 of the 16 districts where surveillance was conducted. The PfK13 469Y and 675V mutations were seen in far northern Uganda in 2016-2017 and increased and spread thereafter, reaching a combined prevalence of 10 to 54% across much of northern Uganda, with spread to other regions. The 469F mutation reached a prevalence of 38 to 40% in one district in southwestern Uganda in 2021-2022. The 561H mutation, previously described in Rwanda, was first seen in southwestern Uganda in 2021, reaching a prevalence of 23% by 2022. The 441L mutation reached a prevalence of 12 to 23% in three districts in western Uganda in 2022. Genetic analysis indicated local emergence of mutant parasites independent of those in Southeast Asia. The emergence of resistance was observed predominantly in areas where effective malaria control had been discontinued or transmission was unstable. CONCLUSIONS: Data from Uganda showed the emergence of partial resistance to artemisinins in multiple geographic locations, with increasing prevalence and regional spread over time. (Funded by the National Institutes of Health.).


Subject(s)
Artemisinins , Drug Resistance , Malaria , Parasites , Protozoan Proteins , Animals , Humans , Artemisinins/pharmacology , Artemisinins/therapeutic use , Benchmarking , Parasites/drug effects , Parasites/genetics , Uganda/epidemiology , Drug Resistance/genetics , Malaria/drug therapy , Malaria/genetics , Malaria/parasitology , Protozoan Proteins/genetics
2.
J Infect Dis ; 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38874098

ABSTRACT

Newly arrived refugees offer insights into malaria epidemiology in their countries of origin. We evaluated asymptomatic refugee children within 7 days of arrival in Uganda from South Sudan and the Democratic Republic of Congo (DRC) in 2022 for parasitemia, parasite species, and Plasmodium falciparum drug resistance markers. Asymptomatic P. falciparum infections were common in both populations. Co-infection with P. malariae was more common in DRC refugees. Prevalences of markers of aminoquinoline resistance (PfCRT K76T, PfMDR1 N86Y) were much higher in South Sudan refugees, of antifolate resistance (PfDHFR C59R and I164L, PfDHPS A437G and K540E) much higher in DRC refugees, and of artemisinin partial resistance (ART-R; PfK13 C469Y and A675V) moderate in both populations. Prevalences of most mutations differed from those seen in Ugandans attending health centers near the refugee centers. Refugee evaluations yielded insights into varied malaria epidemiology and identified markers of ART-R in two previously little-studied countries.

3.
J Infect Dis ; 225(4): 696-704, 2022 02 15.
Article in English | MEDLINE | ID: mdl-34460932

ABSTRACT

BACKGROUND: The Plasmodium falciparum dihydrofolate reductase (PfDHFR) inhibitors pyrimethamine and cycloguanil (the active metabolite of proguanil) have important roles in malaria chemoprevention, but drug resistance challenges their efficacies. A new compound, P218, was designed to overcome resistance, but drug-susceptibility data for P falciparum field isolates are limited. METHODS: We studied ex vivo PfDHFR inhibitor susceptibilities of 559 isolates from Tororo and Busia districts, Uganda, from 2016 to 2020, sequenced 383 isolates, and assessed associations between genotypes and drug-susceptibility phenotypes. RESULTS: Median half-maximal inhibitory concentrations (IC50s) were 42 100 nM for pyrimethamine, 1200 nM for cycloguanil, 13000 nM for proguanil, and 0.6 nM for P218. Among sequenced isolates, 3 PfDHFR mutations, 51I (100%), 59R (93.7%), and 108N (100%), were very common, as previously seen in Uganda, and another mutation, 164L (12.8%), had moderate prevalence. Increasing numbers of mutations were associated with decreasing susceptibility to pyrimethamine, cycloguanil, and P218, but not proguanil, which does not act directly against PfDHFR. Differences in P218 susceptibilities were modest, with median IC50s of 1.4 nM for parasites with mixed genotype at position 164 and 5.7 nM for pure quadruple mutant (51I/59R/108N/164L) parasites. CONCLUSIONS: Resistance-mediating PfDHFR mutations were common in Ugandan isolates, but P218 retained excellent activity against mutant parasites.


Subject(s)
Antimalarials , Folic Acid Antagonists , Malaria, Falciparum , Antimalarials/pharmacology , Antimalarials/therapeutic use , Drug Resistance/genetics , Folic Acid Antagonists/pharmacology , Humans , Malaria, Falciparum/parasitology , Plasmodium falciparum , Polymorphism, Genetic , Proguanil/pharmacology , Pyrimethamine/pharmacology , Pyrimethamine/therapeutic use , Tetrahydrofolate Dehydrogenase/genetics , Tetrahydrofolate Dehydrogenase/metabolism , Uganda
4.
Antimicrob Agents Chemother ; 66(10): e0081722, 2022 10 18.
Article in English | MEDLINE | ID: mdl-36094216

ABSTRACT

The proteasome is a promising target for antimalarial chemotherapy. We assessed ex vivo susceptibilities of fresh Plasmodium falciparum isolates from eastern Uganda to seven proteasome inhibitors: two asparagine ethylenediamines, two macrocyclic peptides, and three peptide boronates; five had median IC50 values <100 nM. TDI8304, a macrocylic peptide lead compound with drug-like properties, had a median IC50 of 16 nM. Sequencing genes encoding the ß2 and ß5 catalytic proteasome subunits, the predicted targets of the inhibitors, and five additional proteasome subunits, identified two mutations in ß2 (I204T, S214F), three mutations in ß5 (V2I, A142S, D150E), and three mutations in other subunits. The ß2 S214F mutation was associated with decreased susceptibility to two peptide boronates, with IC50s of 181 nM and 2635 nM against mutant versus 62 nM and 477 nM against wild type parasites for MMV1579506 and MMV1794229, respectively, although significance could not be formally assessed due to the small number of mutant parasites with available data. The other ß2 and ß5 mutations and mutations in other subunits were not associated with susceptibility to tested compounds. Against culture-adapted Ugandan isolates, two asparagine ethylenediamines and the peptide proteasome inhibitors WLW-vinyl sulfone and WLL-vinyl sulfone (which were not studied ex vivo) demonstrated low nM activity, without decreased activity against ß2 S214F mutant parasites. Overall, proteasome inhibitors had potent activity against P. falciparum isolates circulating in Uganda, and genetic variation in proteasome targets was uncommon.


Subject(s)
Antimalarials , Plasmodium falciparum , Proteasome Inhibitors , Humans , Antimalarials/pharmacology , Antimalarials/chemistry , Asparagine , Drug Resistance/genetics , Ethylenediamines/pharmacology , Malaria, Falciparum/drug therapy , Malaria, Falciparum/parasitology , Peptides/pharmacology , Plasmodium falciparum/drug effects , Plasmodium falciparum/genetics , Proteasome Endopeptidase Complex/genetics , Proteasome Inhibitors/chemistry , Proteasome Inhibitors/pharmacology , Uganda
5.
Antimicrob Agents Chemother ; 65(10): e0077121, 2021 09 17.
Article in English | MEDLINE | ID: mdl-34339273

ABSTRACT

Among novel compounds under recent investigation as potential new antimalarial drugs are three independently developed inhibitors of the Plasmodium falciparum P-type ATPase (PfATP4): KAE609 (cipargamin), PA92, and SJ733. We assessed ex vivo susceptibilities to these compounds of 374 fresh P. falciparum isolates collected in Tororo and Busia districts, Uganda, from 2016 to 2019. Median IC50s were 65 nM for SJ733, 9.1 nM for PA92, and 0.5 nM for KAE609. Sequencing of pfatp4 for 218 of these isolates demonstrated many nonsynonymous single nucleotide polymorphisms; the most frequent mutations were G1128R (69% of isolates mixed or mutant), Q1081K/R (68%), G223S (25%), N1045K (16%), and D1116G/N/Y (16%). The G223S mutation was associated with decreased susceptibility to SJ733, PA92, and KAE609. The D1116G/N/Y mutations were associated with decreased susceptibility to SJ733, and the presence of mutations at both codons 223 and 1116 was associated with decreased susceptibility to PA92 and SJ733. In all of these cases, absolute differences in susceptibilities of wild-type (WT) and mutant parasites were modest. Analysis of clones separated from mixed field isolates consistently identified mutant clones as less susceptible than WT. Analysis of isolates from other sites demonstrated the presence of the G223S and D1116G/N/Y mutations across Uganda. Our results indicate that malaria parasites circulating in Uganda have a number of polymorphisms in PfATP4 and that modestly decreased susceptibility to PfATP4 inhibitors is associated with some mutations now present in Ugandan parasites.


Subject(s)
Antimalarials , Malaria, Falciparum , Adenosine Triphosphatases , Antimalarials/pharmacology , Antimalarials/therapeutic use , Drug Resistance/genetics , Genotype , Humans , Malaria, Falciparum/drug therapy , Plasmodium falciparum/genetics , Protozoan Proteins/genetics , Protozoan Proteins/therapeutic use , Uganda
6.
BMC Infect Dis ; 21(1): 1168, 2021 Nov 19.
Article in English | MEDLINE | ID: mdl-34798852

ABSTRACT

BACKGROUND: Intensive adherence counseling (IAC) is an intervention recommended by the World Health Organization to improve anti-retroviral therapy (ART) adherence among people living with HIV on ART with unsuppressed viral load; and in 2016, the intervention was implemented in Uganda. This study evaluated the effect and experiences of providing IAC in an urban HIV care center in Kampala, Uganda. METHODS: This was a sequential explanatory mixed-method study that compared viral load suppression during IAC implementation (intervention) to the period before IAC at Kisenyi Health centre IV. Data were abstracted from patient files and viral load register. The effect of IAC on viral load suppression and associated factors were analyzed using modified Poisson regression with robust standard errors. Using in-depth interviews and an inductive analysis approach in Atlas-ti 8. We also explored experiences of providing IAC among healthcare workers. RESULTS: A total of 500 records were sampled: 249 (49.8%) in the intervention period and 251 (51.2%) in the pre-intervention period. The mean age was lower during the intervention period 33.1 (± 12.0) than 36.5 (± 13.4) in the pre- intervention period, p = 0.002. More clients were currently on Protease-based regimen in the pre-intervention period 179 (71.3%) than 135 (54.2%) in the intervention period, p ≤ 0.001. In the intervention period, all eligible clients received IAC [249/249 (100.0%)]. Overall, 325 (65.0%) received IAC and of these, 143 (44.1%) achieved viral load suppression compared to 46 (26.3%) who received regular counseling. Receiving IAC significantly increased viral load suppression by 22% (aPR 1.22, 95% CI 1.01-1.47). Clients on Protease-based regimen were less likely to suppress than those on Efavirenz or Nevirapine-based regimens (aPR 0.11, 95% CI 0.08-0.15). All the interviewed healthcare workers lauded IAC for improving ART adherence. However, patient and health care system related factors hindered adherence during IAC. CONCLUSIONS: The full potential of IAC in achieving viral load suppression in this setting has not been reached due to a combination of the patient and health care system related factors. Provision of adequate IAC necessities and use of patient centered approach should be emphasized to obtain the maximum benefit of the intervention.


Subject(s)
Anti-HIV Agents , HIV Infections , Anti-HIV Agents/therapeutic use , Counseling , HIV Infections/drug therapy , Humans , Medication Adherence , Uganda , Viral Load
7.
Epilepsy Behav ; 114(Pt A): 107584, 2021 01.
Article in English | MEDLINE | ID: mdl-33248944

ABSTRACT

BACKGROUND: Epilepsy remains a leading chronic neurological disorder in Low- and Middle-Income Countries. In Uganda, the highest burden is among young rural people. We aimed to; (i) describe socio-economic status (including schooling), and household poverty in adolescents living with epilepsy (ALE) compared to unaffected counterparts in the same communities and (ii) determine the factors associated with the overall quality of life (QoL). METHODS: This was a cross-sectional survey nested within a larger study of ALE compared to age-matched healthy community children in Uganda. Between Sept 2016 to Sept 2017, 154 ALE and 154 healthy community controls were consecutively recruited. Adolescents recruited were frequency and age-matched based on age categories 10-14 and 15-19 years. Clinical history and standardized assessments were conducted. One control participant had incomplete assessment and was excluded. The primary outcome was overall QoL and key variables assessed were schooling status and household poverty. Descriptive and multivariable linear regression analysis were conducted for independent associations with overall QoL. RESULTS: Mean (SD) age at seizure onset was 8.8 (3.9) years and median (IQR) monthly seizure burden was 2 (1-4). Epilepsy was associated with living in homes with high household poverty; 95/154 (61.7%) ALE lived in the poorest homes compared to 68/153 (44.5%) of the healthy adolescents, p = 0.001. Nearly two-thirds of ALE had dropped out of school and only 48/154 (31.2%) were currently attending school compared to 136/153 (88.9%) of healthy controls, p < 0.001. QoL was lowest among ALE who never attended school (p < 0.001), with primary education (p = 0.006) compared to those with at least secondary education. Stigma scores [mean(SD)] were highest among ALE in the poorest [69.1(34.6)], and wealthy [70.2(32.2)] quintiles compared to their counterparts in poorer [61.8(31.7)], medium [68.0(32.7)] and wealthiest [61.5(33.3)] quintiles, though not statistically significant (p = 0.75). After adjusting for covariates, ALE currently attending school had higher overall QoL compared to their counterparts who never attended school (ß = 4.20, 95%CI: 0.90,7.49, p = 0.013). QoL scores were higher among ALE with ≥secondary education than those with no or primary education (ß = 10.69, 95%CI: 1.65, 19.72). CONCLUSIONS: ALE in this rural area are from the poorest households, are more likely to drop out of school and have the lowest QoL. Those with poorer seizure control are most affected. ALE should be included among vulnerable population groups and in addition to schooling, strategies for seizure control and addressing the epilepsy treatment gap in affected homes should be specifically targeted in state poverty eradication programs.


Subject(s)
Epilepsy , Quality of Life , Adolescent , Child , Cross-Sectional Studies , Epilepsy/epidemiology , Humans , Poverty , Uganda/epidemiology
8.
Article in English | MEDLINE | ID: mdl-28923866

ABSTRACT

Dihydroartemisinin-piperaquine (DP) has demonstrated excellent efficacy for the treatment and prevention of malaria in Uganda. However, resistance to both components of this regimen has emerged in Southeast Asia. The efficacy of artemether-lumefantrine, the first-line regimen to treat malaria in Uganda, has also been excellent, but continued pressure may select for parasites with decreased sensitivity to lumefantrine. To gain insight into current drug sensitivity patterns, ex vivo sensitivities were assessed and genotypes previously associated with altered drug sensitivity were characterized for 58 isolates collected in Tororo, Uganda, from subjects presenting in 2016 with malaria from the community or as part of a clinical trial comparing DP chemoprevention regimens. Compared to community isolates, those from trial subjects had lower sensitivities to the aminoquinolines chloroquine, monodesethyl amodiaquine, and piperaquine and greater sensitivities to lumefantrine and mefloquine, an observation consistent with DP selection pressure. Compared to results for isolates from 2010 to 2013, the sensitivities of 2016 community isolates to chloroquine, amodiaquine, and piperaquine improved (geometric mean 50% inhibitory concentrations [IC50] = 248, 76.9, and 19.1 nM in 2010 to 2013 and 33.4, 14.9, and 7.5 nM in 2016, respectively [P < 0.001 for all comparisons]), the sensitivity to lumefantrine decreased (IC50 = 3.0 nM in 2010 to 2013 and 5.4 nM in 2016 [P < 0.001]), and the sensitivity to dihydroartemisinin was unchanged (IC50 = 1.4 nM). These changes were accompanied by decreased prevalence of transporter mutations associated with aminoquinoline resistance and low prevalence of polymorphisms recently associated with resistance to artemisinins or piperaquine. Antimalarial drug sensitivities are changing in Uganda, but novel genotypes associated with DP treatment failure in Asia are not prevalent.


Subject(s)
Antimalarials/therapeutic use , Drug Resistance/genetics , Malaria, Falciparum/drug therapy , Membrane Transport Proteins/genetics , Multidrug Resistance-Associated Proteins/genetics , Plasmodium falciparum/drug effects , Protozoan Proteins/genetics , Adolescent , Amodiaquine/analogs & derivatives , Amodiaquine/therapeutic use , Artemisinins/therapeutic use , Aspartic Acid Endopeptidases/genetics , Aspartic Acid Endopeptidases/metabolism , Child , Child, Preschool , Chloroquine/therapeutic use , Ethanolamines/therapeutic use , Female , Fluorenes/therapeutic use , Gene Expression , Humans , Infant , Inhibitory Concentration 50 , Lumefantrine , Malaria, Falciparum/parasitology , Male , Mefloquine/therapeutic use , Membrane Transport Proteins/metabolism , Multidrug Resistance-Associated Proteins/metabolism , Mutation , Parasitic Sensitivity Tests , Plasmodium falciparum/genetics , Plasmodium falciparum/growth & development , Plasmodium falciparum/metabolism , Protozoan Proteins/metabolism , Quinolines/therapeutic use , Uganda , Young Adult
9.
medRxiv ; 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38947039

ABSTRACT

Background: Understanding COVID-19's impact on children is vital for public health policy, yet age-specific data is scarce, especially in Uganda. This study examines SARS-CoV-2 seroprevalence and risk factors among Ugandan children at two timepoints, along with COVID-19-related knowledge and practices in households, including adult vaccination status. Methods: Baseline surveys were conducted in 12 communities from April to May 2021 (post-Alpha wave) and follow-up surveys in 32 communities from November 2021 to March 2022 (Omicron wave). Household questionnaires and blood samples were collected to test for malaria by microscopy and for SARS-CoV-2 using a Luminex assay. Seroprevalence was estimated at both the survey and community level. Mixed-effects logistic regression models assessed the association between individual and household factors and SARS-CoV-2 seropositivity in children, adjusting for household clustering. Results: More households reported disruptions in daily life at baseline compared to follow-up, though economic impacts lingered. By the follow-up survey, 52.7% of adults had received at least one COVID-19 vaccine dose. Overall seroprevalence in children was higher at follow-up compared to baseline (71.6% versus 19.2%, p < 0.001). Seroprevalence in children ranged across communities from 6-37% at baseline and 50-90% at follow-up. At baseline, children from the poorest households were more likely to be infected. Increasing age remained the only consistent risk factor for SARS-CoV-2 seroconversion at both timepoints. Conclusions: Results indicate that a larger number of children were infected by the Delta and Omicron waves of COVID-19 compared to the Alpha wave. This study is the largest seroprevalence survey in children in Uganda, providing evidence that most children were infected with SARS-CoV-2 before the vaccine was widely available to pediatric populations. Pediatric infections were vastly underreported by case counts, highlighting the importance of seroprevalence surveys in assessing disease burden when testing and reporting rates are limited and many cases are mild or asymptomatic.

10.
Lancet Glob Health ; 12(6): e983-e994, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38762298

ABSTRACT

BACKGROUND: Early detection and diagnosis of acute rheumatic fever and rheumatic heart disease are key to preventing progression, and echocardiography has an important diagnostic role. Standard echocardiography might not be feasible in high-prevalence regions due to its high cost, complexity, and time requirement. Handheld echocardiography might be an easy-to-use, low-cost alternative, but its performance in screening for and diagnosing acute rheumatic fever and rheumatic heart disease needs further investigation. METHODS: In this systematic review and meta-analysis, we searched Embase, MEDLINE, LILACS, and Conference Proceedings Citation Index-Science up to Feb 9, 2024, for studies on the screening and diagnosis of acute rheumatic fever and rheumatic heart disease using handheld echocardiography (index test) or standard echocardiography or auscultation (reference tests) in high-prevalence areas. We included all studies with useable data in which the diagnostic performance of the index test was assessed against a reference test. Data on test accuracy in diagnosing rheumatic heart disease, acute rheumatic fever, or carditis with acute rheumatic fever (primary outcomes) were extracted from published articles or calculated, with authors contacted as necessary. Quality of evidence was appraised using GRADE and QUADAS-2 criteria. We summarised diagnostic accuracy statistics (including sensitivity and specificity) and estimated 95% CIs using a bivariate random-effects model (or univariate random-effects models for analyses including three or fewer studies). Area under the curve (AUC) was calculated from summary receiver operating characteristic curves. Heterogeneity was assessed by visual inspection of plots. This study was registered with PROSPERO (CRD42022344081). FINDINGS: Out of 4868 records we identified 11 studies, and two additional reports, comprising 15 578 unique participants. Pooled data showed that handheld echocardiography had high sensitivity (0·87 [95% CI 0·76-0·93]), specificity (0·98 [0·71-1·00]), and overall high accuracy (AUC 0·94 [0·84-1·00]) for diagnosing rheumatic heart disease when compared with standard echocardiography (two studies; moderate certainty of evidence), with better performance for diagnosing definite compared with borderline rheumatic heart disease. High sensitivity (0·79 [0·73-0·84]), specificity (0·85 [0·80-0·89]), and overall accuracy (AUC 0·90 [0·85-0·94]) for screening rheumatic heart disease was observed when pooling data of handheld echocardiography versus standard echocardiography (seven studies; high certainty of evidence). Most studies had a low risk of bias overall. Some heterogeneity was observed for sensitivity and specificity across studies, possibly driven by differences in the prevalence and severity of rheumatic heart disease, and level of training or expertise of non-expert operators. INTERPRETATION: Handheld echocardiography has a high accuracy and diagnostic performance when compared with standard echocardiography for diagnosing and screening of rheumatic heart disease in high-prevalence areas. FUNDING: World Health Organization. TRANSLATIONS: For the Chinese, French, Italian, Persian, Portuguese, Spanish and Urdu translations of the abstract see Supplementary Materials section.


Subject(s)
Echocardiography , Rheumatic Heart Disease , Humans , Rheumatic Heart Disease/diagnostic imaging , Echocardiography/statistics & numerical data , Echocardiography/methods , Mass Screening/methods , World Health Organization , Practice Guidelines as Topic , Sensitivity and Specificity
11.
medRxiv ; 2024 Feb 04.
Article in English | MEDLINE | ID: mdl-38352505

ABSTRACT

Background: Artemisinin partial resistance, mediated by mutations in the Plasmodium falciparum Kelch13 protein (K13), rapidly spread in South-East Asia (SEA), undermining antimalarial efficacies of artemisinin-based combination therapies (ACT). Validated K13 mutations have recently arisen in Africa, but rates of increase are not well characterized. Methods: We investigated K13 mutation prevalence at 16 sites in Uganda (2016-2022, 6586 samples), and five sites in SEA (2003-2018, 5465 samples) by calculating selection coefficients using Bayesian mixed-effect linear models. We then tested whether SEA K13 mutation prevalence could have been forecast accurately using up to the first five years of available data and forecast future K13 mutation prevalence in Uganda. Findings: The selection coefficient for the prevalence of relevant K13 mutations (441L, 469F/Y, 561H, 675V) was estimated at s=0·383 (95% CrI: 0·247 - 0·528) per year, a 38% relative prevalence increase. Selection coefficients across Uganda were s=0·968 (0·463 - 1·569) for 441L, s=0·153 (-0·445 - 0·727) for 469F, s=0·222 (-0·011 - 0·398) for 469Y, and s=0·152 (-0·023 - 0·312) for 675V. In SEA, the selection coefficient was s=-0·005 (-0·852 - 0·814) for 539T, s=0·574 (-0·092 - 1·201) for 580Y, and s=0·308 (0·089 - 0·536) for all validated K13 mutations. Forecast prevalences for Uganda assuming constant selection neared fixation (>95% prevalence) within a decade (2028-2033) for combined K13 mutations. Interpretation: The selection of K13 mutations in Uganda was at a comparable rate to that observed in SEA, suggesting K13 mutations may continue to increase quickly in Uganda. Funding: NIH R01AI156267, R01AI075045, and R01AI089674.

12.
PLOS Glob Public Health ; 3(2): e0000633, 2023.
Article in English | MEDLINE | ID: mdl-36962948

ABSTRACT

Community antiretroviral groups (CAGs) is one of the innovative and efficient differentiated service delivery models (DSDM) for reaching persons needing human immunodeficiency virus (HIV) treatment in the community. Since DSDM adoption in Uganda, evidence suggests better care outcomes for patients in DSDM compared to counterparts in routine health facility care. However, uptake of CAG models for eligible community groups of persons living with HIV (PLHIV) has been slow in Arua district, Uganda and stakeholders' perceptions regarding its implementation unexplored. The objective of the study was to determine the uptake, barriers and facilitators influencing CAG model implementation in Arua district, Uganda. We conducted a parallel convergent mixed-methods study from March 2020 to December 2020 at Adumi health centre IV and Kuluva hospital in Arua district. We enrolled and extracted data for every fifth virally suppressed participant on antiretroviral therapy (ART) at the two health facilities. Data were analysed using STATA 13.0. Uptake was determined as the proportion of eligible PLHIV that were enrolled into a group. We performed logistic regression to determine factors associated with uptake. We conducted one focus group discussion per facility among healthcare workers involved in the management of PLHIV. We also conducted 7 focus group discussions among PLHIV across the two facilities. Thematic analysis was used to describe the data. A total of 399 PLHIV were eligible for CAG, 61.6% were female, and 44.9% were on dolutegravir (DTG) based regimen. Uptake was 6.8%, 95% CI (4.7-9.7) and was found to be significantly associated with being divorced or separated in a marriage (OR; 0.14, 95%CI; 0.02-0.92, P = 0.014). Members picking drugs in turns, comforting and encouraging others to take the drugs, and health workers advising them to join and stay with other group members were perceived as facilitators to uptake of community antiretroviral group delivery model. Having few and distant eligible members in the local area to form a group, lack of transport among the member to pick the drugs when it's their turn, misunderstandings and lack of confidentiality amongst the members, and lack of partner disclosure were perceived as barriers to uptake of community antiretroviral group delivery model. Uptake of community antiretroviral group delivery model in Arua district is very low. There may be a need to support community antiretroviral group delivery models with income- generating activities, transport facilitation, closer community drug pick-up points and improved partner disclosure support mechanisms among married group members.

13.
Microbiol Spectr ; 11(3): e0523622, 2023 06 15.
Article in English | MEDLINE | ID: mdl-37158739

ABSTRACT

Malaria, especially Plasmodium falciparum infection, remains an enormous problem, and its treatment and control are seriously challenged by drug resistance. New antimalarial drugs are needed. To characterize the Medicines for Malaria Venture pipeline of antimalarials under development, we assessed the ex vivo drug susceptibilities to 19 compounds targeting or potentially impacted by mutations in P. falciparum ABC transporter I family member 1, acetyl-CoA synthetase, cytochrome b, dihydroorotate dehydrogenase, elongation factor 2, lysyl-tRNA synthetase, phenylalanyl-tRNA synthetase, plasmepsin X, prodrug activation and resistance esterase, and V-type H+ ATPase of 998 fresh P. falciparum clinical isolates collected in eastern Uganda from 2015 to 2022. Drug susceptibilities were assessed by 72-h growth inhibition (half-maximum inhibitory concentration [IC50]) assays using SYBR green. Field isolates were highly susceptible to lead antimalarials, with low- to midnanomolar median IC50s, near values previously reported for laboratory strains, for all tested compounds. However, outliers with decreased susceptibilities were identified. Positive correlations between IC50 results were seen for compounds with shared targets. We sequenced genes encoding presumed targets to characterize sequence diversity, search for polymorphisms previously selected with in vitro drug pressure, and determine genotype-phenotype associations. We identified many polymorphisms in target genes, generally in <10% of isolates, but none were those previously selected in vitro with drug pressure, and none were associated with significantly decreased ex vivo drug susceptibility. Overall, Ugandan P. falciparum isolates were highly susceptible to 19 compounds under development as next-generation antimalarials, consistent with a lack of preexisting or novel resistance-conferring mutations in circulating Ugandan parasites. IMPORTANCE Drug resistance necessitates the development of new antimalarial drugs. It is important to assess the activities of compounds under development against parasites now causing disease in Africa, where most malaria cases occur, and to determine if mutations in these parasites may limit the efficacies of new agents. We found that African isolates were generally highly susceptible to the 19 studied lead antimalarials. Sequencing of the presumed drug targets identified multiple mutations in these genes, but these mutations were generally not associated with decreased antimalarial activity. These results offer confidence that the activities of the tested antimalarial compounds now under development will not be limited by preexisting resistance-mediating mutations in African malaria parasites.


Subject(s)
Antimalarials , Malaria, Falciparum , Malaria , Humans , Antimalarials/pharmacology , Antimalarials/therapeutic use , Plasmodium falciparum/genetics , Uganda , Malaria, Falciparum/drug therapy , Malaria, Falciparum/parasitology , Malaria/parasitology , Drug Resistance/genetics , Ligases , Protozoan Proteins/genetics
14.
Campbell Syst Rev ; 18(1): e1216, 2022 Mar.
Article in English | MEDLINE | ID: mdl-36913191

ABSTRACT

Background: Globally, 13% of the youth are not in education, employment or training (NEET). Moreover, this persistent problem has been exacerbated by the shock of Covid-19 pandemic. More youth from disadvantaged backgrounds are likely unemployed than those from better off backgrounds. Thus, the need for increased use of evidence in the design and implementation of youth employment interventions to increase effectiveness and sustainability of interventions and outcomes. Evidence and gap maps (EGMs) can promote evidence-based decision making by guiding policy makers, development partners and researchers to areas with good bodies of evidence and those with little or no evidence. The scope of the Youth Employment EGM is global. The map covers all youth aged 15-35 years. The three broad intervention categories included in the EGM are: strengthening training and education systems, enhancing labour market and, transforming financial sector markets. There are five outcome categories: education and skills; entrepreneurship; employment; welfare and economic outcomes. The EGM contains impact evaluations of interventions implemented to increase youth employment and systematic reviews of such single studies, published or made available between 2000 and 2019. Objectives: The primary objective was to catalogue impact evaluations and systematic reviews on youth employment interventions to improve discoverability of evidence by decision makers, development patterners and researchers, so as to promote evidence-based decision making in programming and implementation of youth employment initiatives. Search Methods: Twenty databases and websites were searched using a validated search strategy. Additional searches included searching within 21 systematic reviews, snowballing 20 most recent studies and citation tracking of 10 most recent studies included in the EGM. Selection Criteria: The study selection criteria followed the PICOS approach of population, intervention, relevant comparison groups, outcomes and study design. Additional criterion is; study publication or availability period of between 2000 and 2021. Only impact evaluations and systematic reviews that included impact evaluations were selected. Data Collection and Analysis: A total of 14,511 studies were uploaded in EPPI Reviewer 4 software, upon which 399 were selected using the criteria provided above. Coding of data took place in EPPI Reviewer basing on predefined codes. The unit of analysis for the report is individual studies where every entry represents a combination of interventions and outcomes. Main Results: Overall, 399 studies (21 systematic reviews and 378 impact evaluations) are included in the EGM. Impact evaluations (n = 378) are much more than the systematic reviews (n = 21). Most impact evaluations are experimental studies (n = 177), followed by non-experimental matching (n = 167) and other regression designs (n = 35). Experimental studies were mostly conducted in both Lower-income countries and Lower Middle Income countries while non-experimental study designs are the most common in both High Income and Upper Middle Income countries. Most evidence is from low quality impact evaluations (71.2%) while majority of systematic reviews (71.4% of 21) are of medium and high quality rating. The area saturated with most evidence is the intervention category of 'training', while the underrepresented are three main intervention sub-categories: information services; decent work policies and; entrepreneurship promotion and financing. Older youth, youth in fragility, conflict and violence contexts, or humanitarian settings, or ethnic minorities or those with criminal backgrounds are least studied. Conclusions: The Youth Employment EGM identifies trends in evidence notably the following: Most evidence is from high-income countries, an indication of the relationship between a country's income status and research productivity.The most common study designs are experimental.Most of the evidence is of low quality. This finding serves to alert researchers, practitioners and policy makers that more rigorous work is needed to inform youth employment interventions. Blending of interventions is practiced. While this could be an indication that blended intervention could be offering better outcomes, this remains an area with a research gap.

15.
PLoS One ; 17(8): e0268122, 2022.
Article in English | MEDLINE | ID: mdl-35984779

ABSTRACT

BACKGROUND: Uganda adopted the HIV Test and Treat in 2016. There is paucity of data about its implementation among hospitalized patients. We aimed to determine the proportion of patients initiating anti-retroviral therapy (ART) during hospitalization, barriers and mortality outcome. METHODS: In this mixed methods cohort study, we enrolled hospitalized patients with a recent HIV diagnosis from three public hospitals in Uganda. We collected data on clinical characteristics, ART initiation and reasons for failure to initiate ART, as well as 30 day outcomes. Healthcare workers in-depth interviews were also conducted and data analyzed by sub-themes. RESULTS: We enrolled 234 patients; females 140/234 (59.8%), median age 34.5 years (IQR 29-42), 195/234 (83.7%) had WHO HIV stage 3 or 4, and 74/116 (63.8%) had CD4 ≤ 200 cell/µL. The proportion who initiated ART during hospitalization was 123/234 (52.6%) (95% CI 46.0-59.1), of these 35/123 (28.5%) initiated ART on the same day of hospitalization, while 99/123 (80.5%) within a week of hospitalization. By 30 days 34/234 (14.5%) (95% CI 10.3-19.7) died. Patients residing ≥ 35 kilometers from the hospital were more likely not to initiate ART during hospitalization, [aRR = 1.39, (95% CI 1.22-1.59). Inadequate patient preparation for ART initiation and advanced HIV disease were highlighted as barriers of ART initiation during hospitalization. CONCLUSION: In this high HIV prevalence setting, only half of newly diagnosed HIV patients are initiated on ART during hospitalization. Inadequate pre-ART patient preparation and advanced HIV are barriers to rapid ART initiation among hospitalized patients in public hospitals.


Subject(s)
Anti-HIV Agents , HIV Infections , Adult , Anti-HIV Agents/therapeutic use , CD4 Lymphocyte Count , Cohort Studies , Female , HIV Infections/diagnosis , HIV Infections/drug therapy , HIV Infections/epidemiology , HIV Testing , Humans , Uganda/epidemiology
16.
Nat Commun ; 13(1): 6353, 2022 10 26.
Article in English | MEDLINE | ID: mdl-36289202

ABSTRACT

Artemisinin partial resistance may facilitate selection of Plasmodium falciparum resistant to combination therapy partner drugs. We evaluated 99 P. falciparum isolates collected in 2021 from northern Uganda, where resistance-associated PfK13 C469Y and A675V mutations have emerged, and eastern Uganda, where these mutations are uncommon. With the ex vivo ring survival assay, isolates with the 469Y mutation (median survival 7.3% for mutant, 2.5% mixed, and 1.4% wild type) and/or mutations in Pfcoronin or falcipain-2a, had significantly greater survival; all isolates with survival >5% had mutations in at least one of these proteins. With ex vivo growth inhibition assays, susceptibility to lumefantrine (median IC50 14.6 vs. 6.9 nM, p < 0.0001) and dihydroartemisinin (2.3 vs. 1.5 nM, p = 0.003) was decreased in northern vs. eastern Uganda; 14/49 northern vs. 0/38 eastern isolates had lumefantrine IC50 > 20 nM (p = 0.0002). Targeted sequencing of 819 isolates from 2015-21 identified multiple polymorphisms associated with altered drug susceptibility, notably PfK13 469Y with decreased susceptibility to lumefantrine (p = 6 × 10-8) and PfCRT mutations with chloroquine resistance (p = 1 × 10-20). Our results raise concern regarding activity of artemether-lumefantrine, the first-line antimalarial in Uganda.


Subject(s)
Antimalarials , Artemisinins , Malaria, Falciparum , Humans , Plasmodium falciparum/genetics , Plasmodium falciparum/metabolism , Antimalarials/pharmacology , Antimalarials/therapeutic use , Lumefantrine/pharmacology , Lumefantrine/therapeutic use , Artemether, Lumefantrine Drug Combination/pharmacology , Artemether, Lumefantrine Drug Combination/therapeutic use , Uganda , Malaria, Falciparum/drug therapy , Drug Resistance/genetics , Artemether/pharmacology , Artemether/therapeutic use , Artemisinins/pharmacology , Artemisinins/therapeutic use , Chloroquine/pharmacology , Drug Combinations , Protozoan Proteins/metabolism
17.
Afr Health Sci ; 21(3): 1048-1058, 2021 Sep.
Article in English | MEDLINE | ID: mdl-35222566

ABSTRACT

INTRODUCTION: In Kampala Uganda, female sex workers (FSWs) have high HIV prevalence (33%). Oral PrEP is a novel HIV prevention intervention that offers hope to decrease HIV incidence in key populations especially among FSWs. Studies have shown that with poor adherence, oral PrEP has no efficacy, and therefore adherence to PrEP is critical among FSWs to maximize HIV prevention. However, implementation data on adherence to PrEP among FSWs is limited so this study sought to assess adherence to PrEP. Specifically, we sought to 1) determine the level of adherence to PrEP among FSWs, and 2) determine factors associated with PrEP adherence. METHODS: This cross-sectional study was conducted from November to December 2018; 126 FSWs using PrEP were interviewed using a questionnaire. Adherence was categorically defined as high adherence and low adherence. Logistic regression was done. RESULTS: Using long-term contraception methods (OR 0.06, 95% CI: 0.04-0.77) and not using condoms with clients (OR 0.07, 95% CI: 0.01-0.42) were negatively associated with high PrEP adherence. CONCLUSION: Barriers to PrEP adherence need to be addressed for successful PrEP implementation to improve adherence going forward. Service care providers should reinforce positive behaviors such as use of condoms devotedly during PrEP breaks.


Subject(s)
Anti-HIV Agents , HIV Infections , Pre-Exposure Prophylaxis , Sex Workers , Anti-HIV Agents/therapeutic use , Cross-Sectional Studies , Female , HIV Infections/epidemiology , Humans , Uganda
18.
Campbell Syst Rev ; 17(4): e1196, 2021 Dec.
Article in English | MEDLINE | ID: mdl-36950344

ABSTRACT

The research question guiding the production of the youth employment evidence and gap map (EGM) is stated as follows: What is the nature and extent of the evidence base of impact evaluations and systematic reviews on youth employment programmes in the world? The primary objective of is to catalogue impact evaluations and systematic reviews on youth employment interventions to enhance discoverability of evidence by decision makers, development patterners and researchers, so as to promote evidence-based decision making in programming and delivery of youth employment initiatives. This evidence gap map is also a primary input into the implementation of Mastercard Foundation's strategy titled "Africa Works: Mastercard Foundation Strategy 2018-2030", which points out sharing of evidence-based knowledge and innovation with stakeholders as a key strategy to be used (Mastercard Foundation). The time frame for the development of the youth EGM will run from the last quarter of 2019 to December 2020. The five secondary objectives are: (i) To construct a framework for the classification of youth employment effectiveness studies. The objective will be achieved through the development of an intervention and outcome framework using an engaged consultative process involving the review team, Mastercard Foundation and other stakeholders. (ii) To identify available evidence, and clusters of evidence, including its quality rating. This will involve activities such as identification of studies using a standardised study search strategy, screening and coding of studies in EPPI Reviewer 4, which is a web-based software program for production of reviews. (iii) To create a map of youth employment effectiveness studies equipped with an appealing user-friendly web-based search content visualisation using interactive mapping software. To achieve this object, data coded in EPPI Reviewer 4 will be exported to another software (EPPI mapper) which is designed for generating EGMs. (iv) To produce a narrative report of the youth employment EGM. This will be achieved through analysis of data in EPPI Reviewer 4 and report writing. To disseminate the EGM to users to increase awareness to support evidence-informed decision-making across countries. We will achieve this objective by organising dissemination workshops, participating in conferences and hosting the evidence and gap on our websites.

19.
BMJ Open ; 11(10): e050296, 2021 10 18.
Article in English | MEDLINE | ID: mdl-34663660

ABSTRACT

INTRODUCTION: Accurate and affordable laboratory testing is key to timely diagnosis and appropriate management of patients with COVID-19. New laboratory test protocols are released into the market under emergency use authorisation with limited evidence on diagnostic test accuracy. As such, robust evidence on the diagnostic accuracy and the costs of available tests is urgently needed to inform policy and practice especially in resource-limited settings. We aim to determine the diagnostic test accuracy, cost-effectiveness and utility of laboratory test strategies for COVID-19 in low-income and middle-income countries. METHODS AND ANALYSIS: This will be a multistaged, protocol-driven systematic review conducted in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for diagnostic test accuracy studies. We will search for relevant literature in at least six public health databases, including PubMed, Google Scholar, MEDLINE, Scopus, Web of Science and the WHO Global Index Medicus. In addition, we will search Cochrane Library, COVID-END and grey literature databases to identify additional relevant articles before double-screening and abstraction of data. We will conduct a structured narrative and quantitative synthesis of the results guided by the Fryback and Thornbury framework for assessing a diagnostic test. The primary outcome is COVID-19 diagnostic test accuracy. Using the GRADE approach specific to diagnostic accuracy tests, we will appraise the overall quality of evidence and report the results following the original PRISMA statement. The protocol is registered with the International Prospective Register of Systematic Reviews (PROSPERO; https://www.crd.york.ac.uk/prospero/). ETHICS AND DISSEMINATION: Ethical review was done by the School of Biomedical Sciences Research Ethics Committee and the Uganda National Council for Science and Technology. The published article will be accessible to policy and decision makers. The findings of this review will guide clinical practice and policy decisions and highlight areas for future research.PROSPERO registration number CRD42020209528.


Subject(s)
COVID-19 , Developing Countries , Humans , Income , Review Literature as Topic , SARS-CoV-2
20.
Lancet Microbe ; 2(9): e441-e449, 2021 09.
Article in English | MEDLINE | ID: mdl-34553183

ABSTRACT

BACKGROUND: Treatment and control of malaria depends on artemisinin-based combination therapies (ACTs) and is challenged by drug resistance, but thus far resistance to artemisinins and partner drugs has primarily occurred in southeast Asia. The aim of this study was to characterise antimalarial drug susceptibility of Plasmodium falciparum isolates from Tororo and Busia districts in Uganda. METHODS: In this prospective longitudinal study, P falciparum isolates were collected from patients aged 6 months or older presenting at the Tororo District Hospital (Tororo district, a site with relatively low malaria incidence) or Masafu General Hospital (Busia district, a high-incidence site) in eastern Uganda with clinical symptoms of malaria, a positive Giemsa-stained blood film for P falciparum, and no signs of severe disease. Ex-vivo susceptibilities to ten antimalarial drugs were measured using a 72-h microplate growth inhibition assay with SYBR Green detection. Relevant P falciparum genetic polymorphisms were characterised by molecular methods. We compared results with those from earlier studies in this region and searched for associations between drug susceptibility and parasite genotypes. FINDINGS: From June 10, 2016, to July 29, 2019, 361 P falciparum isolates were collected in the Busia district and 79 in the Tororo district from 440 participants. Of 440 total isolates, 392 (89%) successfully grew in culture and showed excellent drug susceptibility for chloroquine (median half-maximal inhibitory concentration [IC50] 20·0 nM [IQR 12·0-26·0]), monodesethylamodiaquine (7·1 nM [4·3-8·9]), pyronaridine (1·1 nM [0·7-2·3]), piperaquine (5·6 nM [3·3-8·6]), ferroquine (1·8 nM [1·5-3·3]), AQ-13 (24·0 nM [17·0-32·0]), lumefantrine (5·1 nM [3·2-7·7]), mefloquine (9·5 nM [6·6-13·0]), dihydroartemisinin (1·5 nM [1·0-2·0]), and atovaquone (0·3 nM [0·2-0·4]). Compared with results from our study in 2010-13, significant improvements in susceptibility were seen for chloroquine (median IC50 288·0 nM [IQR 122·0-607·0]; p<0·0001), monodesethylamodiaquine (76·0 nM [44·0-137]; p<0·0001), and piperaquine (21·0 nM [7·6-43·0]; p<0·0001), a small but significant decrease in susceptibility was seen for lumefantrine (3·0 nM [1·1-7·6]; p<0·0001), and no change in susceptibility was seen with dihydroartemisinin (1·3 nM [0·8-2·5]; p=0·64). Chloroquine resistance (IC50>100 nM) was more common in isolates from the Tororo district (11 [15%] of 71), compared with those from the Busia district (12 [4%] of 320; p=0·0017). We showed significant increases between 2010-12 and 2016-19 in the prevalences of wild-type P falciparum multidrug resistance protein 1 (PfMDR1) Asn86Tyr from 60% (391 of 653) to 99% (418 of 422; p<0·0001), PfMDR1 Asp1246Tyr from 60% (390 of 650) to 90% (371 of 419; p<0·0001), and P falciparum chloroquine resistance transporter (PfCRT) Lys76Thr from 7% (44 of 675) to 87% (364 of 417; p<0·0001). INTERPRETATION: Our results show marked changes in P falciparum drug susceptibility phenotypes and genotypes in Uganda during the past decade. These results suggest that additional changes will be seen over time and continued surveillance of susceptibility to key ACT components is warranted. FUNDING: National Institutes of Health and Medicines for Malaria Venture.


Subject(s)
Antimalarials , Malaria, Falciparum , Antimalarials/pharmacology , Chloroquine/pharmacology , Genotype , Humans , Longitudinal Studies , Lumefantrine/therapeutic use , Malaria, Falciparum/drug therapy , Phenotype , Plasmodium falciparum/genetics , Prospective Studies , Uganda/epidemiology
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