Correction: Limitations of rapid diagnostic tests in malaria surveys in areas with varied transmission intensity in Uganda 2017-2019: Implications for selection and use of HRP2 RDTs.

[This corrects the article DOI: 10.1371/journal.pone.0244457.].

Deployment of COVID-19 vaccine in the WHO Eastern Mediterranean Region 2021-23: How do we switch to a life course approach?

In 2020-2021, all countries of the WHO Eastern Mediterranean Region [EMR] introduced COVID-19 vaccine with inequalities in coverage across countries. As for 2023, we reviewed subsequent progress in deployment, coverage, acceptance, and integration. As of 31 December 2023, coverage in EMR reached 51% for primary series and 19 % for the first booster, higher in high income countries (77 % and 44 %, respectively) than in upper middle-income countries (49 % and 20 %), Advance Market Commitment [AMC] non-Gavi eligible countries (47 % and 15 %) and AMC Gavi eligible countries (49 % and 16 %). Thirteen countries measured coverage among healthcare workers (76 % and 43 %, respectively) and 15 among elderly (69 % and 38 %, respectively). Three rounds of the regional Knowledge, Attitudes, and Practices [KAP] survey on COVID-19 vaccine acceptance in 2021-2022 indicated that acceptance increased from 20 % in June-July 2021 to 62 % in October-November 2021, and 77 % in June-July 2022. Those unvaccinated but intending to be vaccinated decreased from 60 % to 23 % and 11 %, respectively. Unvaccinated without intention to be vaccinated decreased from 15 % to 10 % and 11 %, respectively. Twenty out of 22 countries in the region had completely or partially integrated COVID-19 vaccination into the Expanded Programme on Immunization [EPI] and Primary Health Care [PHC]. Overall, challenges to reach high-risk groups persisted as the population was less concerned about Omicron variant of the SARS-CoV-2 virus. Countries should build on the trust, momentum, and lesson-learned generated from COVID-19 vaccination to get the highest risk groups vaccinated and switch from a time bound and project type approach to a sustainable and long-term approach for COVID-19 vaccine delivery that would be integrated into the routine EPI and PHC.

National immunization technical advisory groups (NITAGs) in the WHO Eastern Mediterranean Region (EMR): A decade of shaping immunization policies, 2010-2021.

In the Eastern Mediterranean Region (EMR) of the World Health Organization (WHO), little is known on National Immunization Technical Advisory Groups' (NITAGs) outputs, including recommendations and their outcomes. We abstracted information from the WHO/UNICEF joint reporting forms and extracted implemented immunization policy decisions from the WHO immunization portal. We describe trends in establishments and functionality of NITAGs and immunization policies implemented in EMR from 2010 to 2021. In 2013, all 22 EMR countries had a NITAG, although only 20 remained active in 2021. The number of countries meeting six NITAG process indicators increased from 7 in 2010, to 14 in 2019, then reduced to 12 in 2021. In 2021, the proportion of countries with a functional NITAG decreased with income level, from 83% in high-income countries, to 55% in middle-income countries and 20% in low-income countries. From 2010 to 2021, there were 103 new vaccine introductions, 31 vaccine switches, and 28 schedule changes implemented across all 22 countries, irrespective of income groups. While NITAGs are established and making recommendations in countries, their functionality decreases with income level. Governments should continue to invest in NITAGs, including on strengthening processes and ensuring that recommendations made are based on evidence to decision frameworks.

Genetic diversity and genetic relatedness in Plasmodium falciparum parasite population in individuals with uncomplicated malaria based on microsatellite typing in Eastern and Western regions of Uganda, 2019-2020.

BACKGROUND: Genetic diversity and parasite relatedness are essential parameters for assessing impact of interventions and understanding transmission dynamics of malaria parasites, however data on its status in Plasmodium falciparum populations in Uganda is limited. Microsatellite markers and DNA sequencing were used to determine diversity and molecular characterization of P. falciparum parasite populations in Uganda. METHODS: A total of 147 P. falciparum genomic DNA samples collected from cross-sectional surveys in symptomatic individuals of 2-10 years were characterized by genotyping of seven highly polymorphic neutral microsatellite markers (n = 85) and genetic sequencing of the Histidine Rich Protein 2 (pfhrp2) gene (n = 62). ArcGIS was used to map the geographical distribution of isolates while statistical testing was done using Student's t-test or Wilcoxon's rank-sum test and Fisher's exact test as appropriate at P ≤ 0.05. RESULTS: Overall, 75.5% (95% CI 61.1-85.8) and 24.5% (95% CI14.2-38.9) of parasites examined were of multiclonal (mixed genotype) and single clone infections, respectively. Multiclonal infections occurred more frequently in the Eastern region 73.7% (95% CI 48.8-89.1), P < 0.05. Overall, multiplicity of infection (MOI) was 1.9 (95% CI 1.7-2.1), P = 0.01 that was similar between age groups (1.8 vs 1.9), P = 0.60 and regions (1.9 vs 1.8), P = 0.43 for the < 5 and ≥ 5 years and Eastern and Western regions, respectively. Genomic sequencing of the pfhrp2 exon2 revealed a high level of genetic diversity reflected in 96.8% (60/62) unique sequence types. Repeat type AHHAAAHHATD and HRP2 sequence Type C were more frequent in RDT-/PCR + samples (1.9% vs 1.5%) and (13% vs 8%), P < 0.05 respectively. Genetic relatedness analysis revealed small clusters of gene deleted parasites in Uganda, but no clustering with Eritrean parasites. CONCLUSION: High level of genetic diversity of P. falciparum parasites reflected in the frequency of multiclonal infections, multiplicity of infection and variability of the pfhrp2 gene observed in this study is consistent with the high malaria transmission intensity in these settings. Parasite genetic analysis suggested spontaneous emergence and clonal expansion of pfhrp2 deleted parasites that require close monitoring to inform national malaria diagnosis and case management policies.

Limitations of rapid diagnostic tests in malaria surveys in areas with varied transmission intensity in Uganda 2017-2019: Implications for selection and use of HRP2 RDTs.

BACKGROUND: Plasmodium falciparum histidine-rich protein 2 (HRP2)-based rapid diagnostic tests (RDTs) are exclusively recommended for malaria diagnosis in Uganda; however, their functionality can be affected by parasite-related factors that have not been investigated in field settings. METHODS: Using a cross-sectional design, we analysed 219 RDT-/microscopy+ and 140 RDT+/microscopy+ dried blood spots obtained from symptomatic children aged 2-10 years from 48 districts in Uganda between 2017 and 2019. We aimed to investigate parasite-related factors contributing to false RDT results by molecular characterization of parasite isolates. ArcGIS software was used to map the geographical distribution of parasites. Statistical analysis was performed using chi-square or Fisher's exact tests, with P ≤ 0.05 indicating significance. Odds ratios (ORs) were used to assess associations, while logistic regression was performed to explore possible factors associated with false RDT results. RESULTS: The presence of parasite DNA was confirmed in 92.5% (332/359) of the blood samples. The levels of agreement between the HRP2 RDT and PCR assay results in the (RDT+/microscopy+) and (RDT-/microscopy+) sample subsets were 97.8% (137/140) and 10.9% (24/219), respectively. Factors associated with false-negative RDT results in the (RDT-/microscopy+) samples were parasite density (<1,000/µl), pfhrp2/3 gene deletion and non-P. falciparum species (aOR 2.65, 95% CI: 1.62-4.38, P = 0.001; aOR 4.4, 95% CI 1.72-13.66, P = 0.004; and aOR 18.65, 95% CI: 5.3-38.7, P = 0.001, respectively). Overall, gene deletion and non-P. falciparum species contributed to 12.3% (24/195) and 19.0% (37/195) of false-negative RDT results, respectively. Of the false-negative RDTs results, 80.0% (156/195) were from subjects with low-density infections (< 25 parasites per 200 WBCs or <1,000/µl). CONCLUSION: This is the first evaluation and report of the contributions of pfhrp2/3 gene deletion, non-P. falciparum species, and low-density infections to false-negative RDT results under field conditions in Uganda. In view of these findings, the use of HRP2 RDTs should be reconsidered; possibly, switching to combination RDTs that target alternative antigens, particularly in affected areas, may be beneficial. Future evaluations should consider larger and more representative surveys covering other regions of Uganda.

Molecular surveillance reveals the presence of pfhrp2 and pfhrp3 gene deletions in Plasmodium falciparum parasite populations in Uganda, 2017-2019.

BACKGROUND: Histidine-rich protein-2 (HRP2)-based rapid diagnostic tests (RDTs) are the only RDTs recommended for malaria diagnosis in Uganda. However, the emergence of Plasmodium falciparum histidine rich protein 2 and 3 (pfhrp2 and pfhrp3) gene deletions threatens their usefulness as malaria diagnostic and surveillance tools. The pfhrp2 and pfhrp3 gene deletions surveillance was conducted in P. falciparum parasite populations in Uganda. METHODS: Three-hundred (n = 300) P. falciparum isolates collected from cross-sectional malaria surveys in symptomatic individuals in 48 districts of eastern and western Uganda were analysed for the presence of pfhrp2 and pfhrp3 genes. Presence of parasite DNA was confirmed by PCR amplification of the 18s rRNA gene, msp1 and msp2 single copy genes. Presence or absence of deletions was confirmed by amplification of exon1 and exon2 of pfhrp2 and pfhrp3 using gene specific PCR. RESULTS: Overall, pfhrp2 and pfhrp3 gene deletions were detected in 29/300 (9.7%, 95% CI 6.6-13.6%) parasite isolates. The pfhrp2 gene was deleted in 10/300 (3.3%, 95% CI 1.6-6.0%) isolates, pfhrp3 in 9/300 (3.0%, 95% CI 1.4-5.6%) while both pfhrp2 and pfhrp3 were deleted in 10/300 (3.3%, 95% CI 1.6-6.0%) parasite isolates. Proportion of pfhrp2/3 deletions was higher in the eastern 14.7% (95% CI 9.7-20.0%) compared to the western region 3.1% (95% CI 0.8-7.7%), p = 0.001. Geographical location was associated with gene deletions aOR 6.25 (2.02-23.55), p = 0.003. CONCLUSIONS: This is the first large-scale survey reporting the presence of pfhrp2/3 gene deletions in P. falciparum isolates in Uganda. Roll out of RDTs for malaria diagnosis should take into consideration the existence of pfhrp2/3 gene deletions particularly in areas where they were detected. Periodic pfhrp2/3 surveys are recommended to inform future decisions for deployment of alternative RDTs.

Predicting the Impact of COVID-19 and the Potential Impact of the Public Health Response on Disease Burden in Uganda.

The COVID-19 pandemic and public health "lockdown" responses in sub-Saharan Africa, including Uganda, are now widely reported. Although the impact of COVID-19 on African populations has been relatively light, it is feared that redirecting focus and prioritization of health systems to fight COVID-19 may have an impact on access to non-COVID-19 diseases. We applied age-based COVID-19 mortality data from China to the population structures of Uganda and non-African countries with previously established outbreaks, comparing theoretical mortality and disability-adjusted life years (DALYs) lost. We then predicted the impact of possible scenarios of the COVID-19 public health response on morbidity and mortality for HIV/AIDS, malaria, and maternal health in Uganda. Based on population age structure alone, Uganda is predicted to have a relatively low COVID-19 burden compared with an equivalent transmission in comparison countries, with 12% of the mortality and 19% of the lost DALYs predicted for an equivalent transmission in Italy. By contrast, scenarios of the impact of the public health response on malaria and HIV/AIDS predict additional disease burdens outweighing that predicted from extensive SARS-CoV-2 transmission. Emerging disease data from Uganda suggest that such deterioration may already be occurring. The results predict a relatively low COVID-19 impact on Uganda associated with its young population, with a high risk of negative impact on non-COVID-19 disease burden from a prolonged lockdown response. This may reverse hard-won gains in addressing fundamental vulnerabilities in women and children's health, and underlines the importance of tailoring COVID-19 responses according to population structure and local disease vulnerabilities.

Measuring health facility readiness and its effects on severe malaria outcomes in Uganda.

There is paucity of evidence for the role of health service delivery to the malaria decline in Uganda We developed a methodology to quantify health facility readiness and assessed its role on severe malaria outcomes among lower-level facilities (HCIIIs and HCIIs) in the country. Malaria data was extracted from the Health Management Information System (HMIS). General service and malaria-specific readiness indicators were obtained from the 2013 Uganda service delivery indicator survey. Multiple correspondence analysis (MCA) was used to construct a composite facility readiness score based on multiple factorial axes. Geostatistical models assessed the effect of facility readiness on malaria deaths and severe cases. Malaria readiness was achieved in one-quarter of the facilities. The composite readiness score explained 48% and 46% of the variation in the original indicators compared to 23% and 27%, explained by the first axis alone for HCIIIs and HCIIs, respectively. Mortality rate was 64% (IRR = 0.36, 95% BCI: 0.14-0.61) and 68% (IRR = 0.32, 95% BCI: 0.12-0.54) lower in the medium and high compared to low readiness groups, respectively. A composite readiness index is more informative and consistent than the one based on the first MCA factorial axis. In Uganda, higher facility readiness is associated with a reduced risk of severe malaria outcomes.

Interactions between climatic changes and intervention effects on malaria spatio-temporal dynamics in Uganda.

BACKGROUND: Although malaria burden in Uganda has declined since 2009 following the scale-up of interventions, the disease is still the leading cause of hospitalization and death. Transmission remains high and is driven by suitable weather conditions. There is a real concern that intervention gains may be reversed by climatic changes in the country. In this study, we investigate the effects of climate on the spatio-temporal trends of malaria incidence in Uganda during 2013-2017. METHODS: Bayesian spatio-temporal negative binomial models were fitted on district-aggregated monthly malaria cases, reported by two age groups, defined by a cut-off age of 5 years. Weather data was obtained from remote sensing sources including rainfall, day land surface temperature (LSTD) and night land surface temperature (LSTN), Normalized Difference Vegetation Index (NDVI), altitude, land cover, and distance to water bodies. Spatial and temporal correlations were taken into account by assuming a conditional autoregressive and a first-order autoregressive process on district and monthly specific random effects, respectively. Fourier trigonometric functions modeled seasonal fluctuations in malaria transmission. The effects of climatic changes on the malaria incidence changes between 2013 and 2017 were estimated by modeling the difference in time varying climatic conditions at the two time points and adjusting for the effects of intervention coverage, socio-economic status and health seeking behavior. RESULTS: Malaria incidence declined steadily from 2013 to 2015 and then increased in 2016. The decrease was by over 38% and 20% in children <5 years and individuals ≥5 years, respectively. Temporal trends depict a strong bi-annual seasonal pattern with two peaks during April-June and October-December. The annual average of rainfall, LSTD and LSTN increased by 3.7 mm, 2.2 °C and 1.0 °C, respectively, between 2013 and 2017, whereas NDVI decreased by 6.8%. On the one hand, the increase in LSTD and decrease in NDVI were associated with a reduction in the incidence decline. On the other hand, malaria interventions and treatment seeking behavior had reverse effects, that were stronger compared to the effects of climatic changes. Important interactions between interventions with NDVI and LSTD suggest a varying impact of interventions on malaria burden in different climatic conditions. CONCLUSION: Climatic changes in Uganda during the last five years contributed to a favorable environment for malaria transmission, and had a detrimental effect on malaria reduction gains achieved through interventions scale-up efforts. The NMCP should create synergies with the National Meteorological Authority with an ultimate goal of developing a Malaria Early Warning System to mitigate adverse climatic change effects on malaria risk in the country.

The effect of case management and vector-control interventions on space-time patterns of malaria incidence in Uganda.

BACKGROUND: Electronic reporting of routine health facility data in Uganda began with the adoption of the District Health Information Software System version 2 (DHIS2) in 2011. This has improved health facility reporting and overall data quality. In this study, the effects of case management with artemisinin-based combination therapy (ACT) and vector control interventions on space-time patterns of disease incidence were determined using DHIS2 data reported during 2013-2016. METHODS: Bayesian spatio-temporal negative binomial models were fitted on district-aggregated monthly malaria cases, reported by two age groups, defined by a cut-off age of 5 years. The effects of interventions were adjusted for socio-economic and climatic factors. Spatial and temporal correlations were taken into account by assuming a conditional autoregressive and a first-order autoregressive AR(1) process on district and monthly specific random effects, respectively. Fourier trigonometric functions were incorporated in the models to take into account seasonal fluctuations in malaria transmission. RESULTS: The temporal variation in incidence was similar in both age groups and depicted a steady decline up to February 2014, followed by an increase from March 2015 onwards. The trends were characterized by a strong bi-annual seasonal pattern with two peaks during May-July and September-December. Average monthly incidence in children < 5 years declined from 74.7 cases (95% CI 72.4-77.1) in 2013 to 49.4 (95% CI 42.9-55.8) per 1000 in 2015 and followed by an increase in 2016 of up to 51.3 (95% CI 42.9-55.8). In individuals ≥ 5 years, a decline in incidence from 2013 to 2015 was followed by an increase in 2016. A 100% increase in insecticide-treated nets (ITN) coverage was associated with a decline in incidence by 44% (95% BCI 28-59%). Similarly, a 100% increase in ACT coverage reduces incidence by 28% (95% BCI 11-45%) and 25% (95% BCI 20-28%) in children < 5 years and individuals ≥ 5 years, respectively. The ITN effect was not statistically important in older individuals. The space-time patterns of malaria incidence in children < 5 are similar to those of parasitaemia risk predicted from the malaria indicator survey of 2014-15. CONCLUSION: The decline in malaria incidence highlights the effectiveness of vector-control interventions and case management with ACT in Uganda. This calls for optimizing and sustaining interventions to achieve universal coverage and curb reverses in malaria decline.

The contribution of malaria control interventions on spatio-temporal changes of parasitaemia risk in Uganda during 2009-2014.

BACKGROUND: In Uganda, malaria vector control interventions and case management with Artemisinin Combination Therapies (ACTs) have been scaled up over the last few years as a result of increased funding. Data on parasitaemia prevalence among children less than 5 years old and coverage of interventions was collected during the first two Malaria Indicator Surveys (MIS) conducted in 2009 and 2014, respectively. In this study, we quantify the effects of control interventions on parasitaemia risk changes between the two MIS in a spatio-temporal analysis. METHODS: Bayesian geostatistical and temporal models were fitted on the MIS data of 2009 and 2014. The models took into account geographical misalignment in the locations of the two surveys and adjusted for climatic changes and socio-economic differentials. Parasitaemia risk was predicted over a 2 × 2 km2 grid and the number of infected children less than 5 years old was estimated. Geostatistical variable selection was applied to identify the most important ITN coverage indicators. A spatially varying coefficient model was used to estimate intervention effects at sub-national level. RESULTS: The coverage of Insecticide Treated Nets (ITNs) and ACTs more than doubled at country and sub-national levels during the period 2009-2014. The coverage of Indoor Residual Spraying (IRS) remained static at all levels. ITNs, IRS, and ACTs were associated with a reduction in parasitaemia odds of 19% (95% BCI: 18-29%), 78% (95% BCI: 67-84%), and 34% (95% BCI: 28-66%), respectively. Intervention effects varied with region. Higher socio-economic status and living in urban areas were associated with parasitaemia odds reduction of 46% (95% BCI: 0.51-0.57) and 57% (95% BCI: 0.40-0.53), respectively. The probability of parasitaemia risk decline in the country was 85% and varied from 70% in the North-East region to 100% in Kampala region. The estimated number of children infected with malaria declined from 2,480,373 in 2009 to 825,636 in 2014. CONCLUSIONS: Interventions have had a strong effect on the decline of parasitaemia risk in Uganda during 2009-2014, albeit with varying magnitude in the regions. This success should be sustained by optimizing ITN coverage to achieve universal coverage.

Geostatistical modelling of malaria indicator survey data to assess the effects of interventions on the geographical distribution of malaria prevalence in children less than 5 years in Uganda.

BACKGROUND: Malaria burden in Uganda has declined disproportionately among regions despite overall high intervention coverage across all regions. The Uganda Malaria Indicator Survey (MIS) 2014-15 was the second nationally representative survey conducted to provide estimates of malaria prevalence among children less than 5 years, and to track the progress of control interventions in the country. In this present study, 2014-15 MIS data were analysed to assess intervention effects on malaria prevalence in Uganda among children less than 5 years, assess intervention effects at regional level, and estimate geographical distribution of malaria prevalence in the country. METHODS: Bayesian geostatistical models with spatially varying coefficients were used to determine the effect of interventions on malaria prevalence at national and regional levels. Spike-and-slab variable selection was used to identify the most important predictors and forms. Bayesian kriging was used to predict malaria prevalence at unsampled locations. RESULTS: Indoor Residual Spraying (IRS) and Insecticide Treated Nets (ITN) ownership had a significant but varying protective effect on malaria prevalence. However, no effect was observed for Artemisinin Combination-based Therapies (ACTs). Environmental factors, namely, land cover, rainfall, day and night land surface temperature, and area type were significantly associated with malaria prevalence. Malaria prevalence was higher in rural areas, increased with the child's age, and decreased with higher household socioeconomic status and higher level of mother's education. The highest prevalence of malaria in children less than 5 years was predicted for regions of East Central, North East and West Nile, whereas the lowest was predicted in Kampala and South Western regions, and in the mountainous areas in Mid-Western and Mid-Eastern regions. CONCLUSIONS: IRS and ITN ownership are important interventions against malaria prevalence in children less than 5 years in Uganda. The varying effects of the interventions calls for selective implementation of control tools suitable to regional ecological settings. To further reduce malaria burden and sustain malaria control in Uganda, current tools should be supplemented by health system strengthening, and socio-economic development.

Symptom burden in HIV-infected adults at time of HIV diagnosis in rural Uganda.

PURPOSE: This study aimed to measure symptom burden prior to antitetroviral therapy (ART) initiation in a population of adults with low CD4 presenting for human immunodeficiency virus (HIV) care and treatment in Uganda, and to explore the relationship between World Health Organization (WHO) stage, CD4 count, and symptomatology. METHODS: HIV-infected, ART-naïve adults with CD4 less than 200 cells per microliter referred from voluntary testing and counseling services in rural Uganda for potential enrollment into a large double-blinded placebo-controlled trial were invited to completed the Memorial Symptom Assessment Scale-Short Form (MSAS-SF). This is a validated symptom assessment tool that records the presence and severity of 37 physical and 4 psychological symptoms. RESULTS: Two hundred twelve subjects were enrolled. The mean total number of symptoms was 14.0 (standard deviation [SD] = 6). The 10 most common symptoms were pain (76%), weight loss (70%), itching (67%), feeling drowsy/tired (61%), and lack of energy (61%), numbness /tingling in hands or feet (57%), cough (53%) skin changes (52%), worry (51%), and lack of appetite (49%). The median number of symptoms was not associated with WHO stage CD4 count group. CONCLUSION: This study demonstrates that the burden of HIV-related symptoms in individuals presenting for care in Uganda is significant and debilitating.