An intervention to improve lumbar puncture rates for meningitis surveillance in children at four secondary health facilities in Malawi: A before/after analysis.

OBJECTIVES: A lumbar puncture (LP) procedure plays a key role in meningitis diagnosis. In Malawi and other sub-Saharan African countries, LP completion rates are sometimes poor, making meningitis surveillance challenging. Our objective was to measure LP rates following an intervention to improve these during a sentinel hospital meningitis surveillance exercise in Malawi. METHODS: We conducted a before/after intervention analysis among under-five children admitted to paediatric wards at four secondary health facilities in Malawi. We used local and World Health Organization (WHO) guidelines to determine indications for LP, as these are widely used in low- and middle-income countries (LMIC). The intervention comprised of refresher trainings for facility staff on LP indications and procedure, use of automated reminders to perform LP in real time in the wards, with an electronic data management system, and addition of surveillance-specific clinical officers to support existing health facility staff with performing LPs. Due to the low numbers in the before/after analysis, we also performed a during/after analysis to supplement the findings. RESULTS: A total of 13,375 under-five children were hospitalised over the 21 months window for this analysis. The LP rate was 10.4% (12/115) and 60.4% (32/53) in the before/after analysis, respectively, and 43.8% (441/1006) and 72.5% (424/599) in the supplemental during/after analysis, respectively. In our intervention-specific analysis among the three individual components, there were improvements in the LP rate by 48% (p < 0.001) following the introduction of surveillance-specific clinical officers, 10% (p < 0.001) following the introduction of automated reminders to perform an LP and 13% following refresher training. CONCLUSIONS: This analysis demonstrated a rise in LP rates following our intervention. This intervention package may be considered for planning future facility-based meningitis surveillances in similar low-resource settings.

Occurrence and Distribution of Nonfalciparum Malaria Parasite Species Among Adolescents and Adults in Malawi.

BACKGROUND: Plasmodium falciparum malaria dominates throughout sub-Saharan Africa, but the prevalence of Plasmodium malariae, Plasmodium ovale spp., and Plasmodium vivax increasingly contribute to infection in countries that control malaria using P. falciparum-specific diagnostic and treatment strategies. METHODS: We performed quantitative polymerase chain reaction (qPCR) on 2987 dried blood spots from the 2015-2016 Malawi Demographic and Health Survey to identify presence and distribution of nonfalciparum infection. Bivariate models were used to determine species-specific associations with demographic and environmental risk factors. RESULTS: Nonfalciparum infections had broad spatial distributions. Weighted prevalence was 0.025 (SE, 0.004) for P. malariae, 0.097 (SE, 0.008) for P. ovale spp., and 0.001 (SE, 0.0005) for P. vivax. Most infections (85.6%) had low-density parasitemias ≤ 10 parasites/µL, and 66.7% of P. malariae, 34.6% of P. ovale spp., and 40.0% of P. vivax infections were coinfected with P. falciparum. Risk factors for P. malariae were like those known for P. falciparum; however, there were few risk factors recognized for P. ovale spp. and P. vivax, perhaps due to the potential for relapsing episodes. CONCLUSIONS: The prevalence of any nonfalciparum infection was 11.7%, with infections distributed across Malawi. Continued monitoring of Plasmodium spp. becomes critical as nonfalciparum infections become important sources of ongoing transmission.

Household Prevalence of Plasmodium falciparum, Plasmodium vivax, and Plasmodium ovale in the Democratic Republic of the Congo, 2013-2014.

In a cross-sectional molecular study in the Democratic Republic of the Congo, 78% of households had ≥1 member infected with Plasmodium falciparum, Plasmodium vivax, and/or Plasmodium ovale spp.; 47% of children and 33% of adults tested positive for ≥1 species. Risk factors varied by species and age group.

Uptake and safety of community-based "screen-and-treat" with thermal ablation preventive therapy for cervical cancer prevention in rural Lilongwe, Malawi.

Malawi has the highest invasive cervical cancer (ICC) mortality rate worldwide, and ICC is the leading cause of cancer death among women. In 2004, Malawi adopted visual inspection with acetic acid (VIA) and ablative treatment with cryotherapy. However, screening coverage has remained low (<30%) and few women (<50%) who require ablative treatment receive it. Additional barriers include long distances to health facilities and challenges with maintaining gas supplies. Thermal ablation is a safe and effective alternative to cryotherapy. We assessed the safety and uptake of community-based ICC screening with VIA and same-day treatment using a handheld thermocoagulator (HTU) in rural Malawi. We held educational talks alongside community leaders and conducted VIA screening in nonclinic community settings to nonpregnant women aged 25 to 49 years without history of hysterectomy or genital cancer/precancer. Eligible women received same-day thermal ablation and HIV testing/counseling. We collected cervical biopsies before treatment and followed up women at Weeks 6 and 12, with repeat biopsy at Week 12. Between July and August 2017, 408 (88%) of 463 eligible women underwent VIA. Overall, 7% (n = 30) of women had a positive VIA, of whom 93% (n = 28) underwent same-day thermal ablation. Among the 30 VIA-positive women, 5 had cervical intraepithelial neoplasia (CIN) 1, 4 had CIN 2/3 and 21 had benign histologic findings. Abnormal vaginal discharge (60%) and light vaginal bleeding (52%) were the most reported adverse events. There was high uptake of the community-based ICC screening in the study population and treatment was safe in this setting. Similar strategies that minimize false-positive results are urgently needed in Malawi.

Gastrointestinal endoscopy experience of surgical trainees throughout rural Africa.

BACKGROUND: Gastrointestinal endoscopy (GIE) is not routinely accessible in many parts of rural Africa. As surgical training expands and technology progresses, the capacity to deliver endoscopic care to patients improves. We aimed to describe the current burden of gastrointestinal (GI) disease undergoing GIE by examining the experience of surgical training related to GIE. METHODS: A retrospective review was conducted on GIE procedures performed by trainees with complete case logs during 5-year general surgery training at Pan-African Academy of Christian Surgeons (PAACS) sites. Cases were classified according to diagnosis and/or indication, anatomic location, intervention, adverse events, and outcomes. Comparisons were performed by institutional location and case volumes. Analysis was performed for trainee self-reported autonomy by post-graduate year and case volume experience. RESULTS: Twenty trainees performed a total of 2181 endoscopic procedures. More upper endoscopies (N = 1,853) were performed than lower endoscopies (N = 325). Of all procedures, 546 (26.7%) involved a cancer or mass, 267 (12.2%) involved a report of blood loss, and 452 (20.7%) reported pain as a component of the diagnosis. Interventions beyond biopsy were reported in 555 (25%) procedures. Esophageal indications predominated the upper endoscopies, particularly esophageal cancer. Trainees in high-volume centers and in East Africa performed more interventional endoscopy and procedures focused on esophageal cancer. Procedure logs documented adverse events in 39 cases (1.8% of all procedures), including 16 patients (0.8%) who died within 30 days of the procedure. Self-reported autonomy improved with both increased endoscopy experience and post-graduate year. CONCLUSIONS: GIE is an appropriate component of general surgery residency training in Africa, and adequate training can be provided, particularly in upper GI endoscopy, and includes a wide variety of endoscopic therapeutic interventions.

Operative Case Volume Minimums Necessary for Surgical Training Throughout Rural Africa.

BACKGROUND: Resident operative case volumes are an important aspect of surgical education, and minimums are required in Accreditation Council for Graduate Medical Education (ACGME) programs. Minimum operative case volumes for training do not exist in rural Africa. Our objective was to determine the optimal minimum operative case volume necessary for general surgery training in rural Africa. METHODS: A cross-sectional census electronic survey was conducted among faculty (N = 24) and graduates (N = 56) of Pan-African Academy of Christian Surgeons training programs. Three equally weighted exposures (median minimum case volume suggested by participants, operative experience of prior graduates, and comparisons with ACGME minimums), adjusted from responses to targeted questions, were utilized to construct an optimal minimum operative case volume for training. RESULTS: Sixty-four surgeons were contacted and 40 (13 faculty, 24 graduates, and 3 graduates who became faculty) participated. All participants thought operative case minimums were necessary, and the majority (98%) felt current training adequately prepared surgeons for their setting. Constructed optimal case volumes included 1000 major cases with fewer required cases than ACGME in abdomen, breast, thoracic, vascular, endoscopy, and laparoscopy and more required cases than ACGME for alimentary tract, endocrine, operative trauma, skin and soft tissue, pediatric, and plastic surgery. Other categories (gynecology, orthopedics, and urology) were deemed necessary for surgical training, with regional differences. Prior graduates satisfied the overall, but not category-specific, proposed minimums. CONCLUSIONS: The surveyed surgeons highlighted the need for diverse surgical training with minimum exposures. They described increased need for cases reflecting regional variations with a desire for more experience in categories less common at their institutions.

Surgical Training Throughout Africa: A Review of Operative Case Volumes at Multiple Training Centers.

BACKGROUND: Adequate surgical training is paramount to produce competent surgeons to address the global burden of surgical disease. The Pan-African Academy of Christian Surgeons (PAACS) has general surgery training programs in eight countries. Operative case volumes have been positively associated with improved trainee performance and patient outcomes. For certification in the USA, 850 total operations are required from defined case categories. Yet, little is known about the operative experience of surgical trainees throughout Africa. METHODS: Operative procedures were reviewed, categorized, and validated from a cohort of PAACS graduates and compared to graduates from Accreditation Council for Graduate Medical Education (ACGME) programs. The primary and secondary outcomes were total case volumes and cases within ACGME-defined categories. Regional variations were explored. RESULTS: Twenty PAACS trainees, from five programs in four countries, performed 38,267 unique procedures. ACGME reports on 1211 residents from 251 programs. PAACS graduates logged more major cases (median 1448) than ACGME graduates (median 993) (p value = 0·0001). PAACS graduates performed more gynecology and obstetrics, orthopedics, head and neck, urology, endocrine, operative trauma, pediatric surgery, plastic surgery, and skin and soft tissue cases. US graduates performed more cases in abdomen, alimentary tract, breast, thoracic, and vascular categories. Comparison between regions demonstrated volume and category variations between Kenya and Gabon, Ethiopia, and Cameroon. CONCLUSION: PAACS trainees perform more operations than ACGME trainees with differences in distribution. This experience can serve as a model for regional educational programs seeking to address the broad and largely unmet burden of surgical disease.

Curative Surgery Improves Survival for Colorectal Cancer in Rural Kenya.

BACKGROUND/AIMS: Colorectal cancer (CRC) is increasing in low- and middle-income countries. Surgical care is essential for the treatment. Many patients do not have access to curative surgery for colorectal cancer in rural Kenya. To better understand the impact of surgical care on colorectal cancer in a resource-limited setting, we compared the experience of patients undergoing operations to those who did not. METHODS: All patients with histologically confirmed CRC at Tenwek Hospital from January 1, 1999, to December 31, 2017, were reviewed. Demographic and clinical data were extracted from records when available. The exposure was either curative operation, palliative operation, or no operation. The primary outcome was survival at 5 years, assessed with Cox proportional hazard analysis after propensity-score matching for age, sex, tumor site, time period, and stage. RESULTS: One hundred and sixty-five patients were identified on chart review. Survival information was available for 150 patients with a median follow-up of 319 days. Fifty-two percent had colon cancer and 48% had rectal cancer. At diagnosis, the mean age was 55.4 years (SD: 16.7) and the male to female ratio was 1.1:1. Thirty-nine percent underwent curative operations, 25% palliative operations, and 36% no operations. One-year survival was estimated to be 98% for curative surgery, 73% for palliative surgery, and 83% for no surgery (p = 0.0005). On crude analysis, 5-year survival improved with curative operation in comparison to no operation with a hazard ratio of 0.30 (CI: 0.14-0.64) (p = 0.002). After propensity matching, the hazard ratio for curative operation versus no operation remained significant, 0.34 (CI: 0.14-0.80) (p = 0.01). CONCLUSIONS: Curative surgery improves survival in our resource-limited environment. Although various factors contribute to the use of surgical treatment, the survival advantage persists after adjusted analysis. Barriers exist for access to prompt surgical evaluation and treatment. Surgical care should be a priority to address the increasing burden of CRC in resource-limited settings.

Real-world experience using hydroxyurea in children with sickle cell disease in Lilongwe, Malawi.

INTRODUCTION: Sickle cell disease (SCD) is among the most common inherited hematologic diseases in sub-Saharan Africa (SSA). Historically, hydroxyurea administration in SSA has been restricted due to limited region-specific evidence for safety and efficacy. METHODS: We conducted a prospective observational cohort study of pediatric patients with SCD in Malawi. From January 2015 to November 2017, hydroxyurea at doses of 10-20 mg/kg/day was administered to children with clinically severe disease (targeted use policy). From December 2017 to July 2018, hydroxyurea was prescribed to all patients (universal use policy). RESULTS: Of 187 patients with SCD, seven (3.7%) died and 23 (12.3%) were lost to follow-up. The majority (135, 72.2%) were prescribed hydroxyurea, 59 (43.7%) under the targeted use policy and 76 (56.3%) under the universal use policy. There were no documented severe toxicities. Under the targeted use policy, children with SCD demonstrated absolute decreases in the rates of hospitalization (-4.1 per 1000 person-days; -7.2, -1.0; P = .004), fevers (-4.2 per 1000 person-days; -7.2, -1.1; P = .002), transfusions (-2.3 per 1000 person-days; 95% confidence interval: -4.9, 0.3; P = .06), and annual school absenteeism (-51.2 per person-year; -60.1, -42.3; P < .0001) within 6 months of hydroxyurea commencement. CONCLUSION: We successfully implemented universal administration of hydroxyurea to children with SCD at a tertiary hospital in Malawi. Similar to recently reported trials, hydroxyurea was safe and effective during routine programmatic experience, with clinical benefits particularly among high-risk children. This highlights the importance of continued widespread scale-up of hydroxyurea within SCD programs across SSA.

Modeling resource allocation strategies for insecticide-treated bed nets to achieve malaria eradication.

Large reductions in the global malaria burden have been achieved, but plateauing funding poses a challenge for progressing towards the ultimate goal of malaria eradication. Using previously published mathematical models of Plasmodium falciparum and Plasmodium vivax transmission incorporating insecticide-treated nets (ITNs) as an illustrative intervention, we sought to identify the global funding allocation that maximized impact under defined objectives and across a range of global funding budgets. The optimal strategy for case reduction mirrored an allocation framework that prioritizes funding for high-transmission settings, resulting in total case reductions of 76% and 66% at intermediate budget levels, respectively. Allocation strategies that had the greatest impact on case reductions were associated with lesser near-term impacts on the global population at risk. The optimal funding distribution prioritized high ITN coverage in high-transmission settings endemic for P. falciparum only, while maintaining lower levels in low-transmission settings. However, at high budgets, 62% of funding was targeted to low-transmission settings co-endemic for P. falciparum and P. vivax. These results support current global strategies to prioritize funding to high-burden P. falciparum-endemic settings in sub-Saharan Africa to minimize clinical malaria burden and progress towards elimination, but highlight a trade-off with 'shrinking the map' through a focus on near-elimination settings and addressing the burden of P. vivax.

Prevalence of Falciparum and non-Falciparum Malaria in the 2014-15 Rwanda Demographic Health Survey.

Background: Malaria remains a major cause of morbidity in sub-Saharan Africa. Undetected asymptomatic falciparum malaria results in a large transmission reservoir and there is evidence of increasing non-falciparum malaria as malaria is controlled in Africa, both resulting in challenges for malaria control programs. Methods: We performed quantitative real time PCR for 4 malaria species in 4,596 individuals from the 2014-2015 Rwanda Demographic Health Survey. Bivariate models were used to determine species-specific associations with risk factors. Results: Asymptomatic falciparum malaria, P. ovale spp., and P. malariae infection had broad spatial distribution across Rwanda. P. vivax infection was rare. Overall infection prevalence was 23.6% (95%CI [21.7%, 26.0%]), with falciparum and non-falciparum at 17.6% [15.9%, 19.0%] and 8.3% [7.0%, 10.0%], respectively. Parasitemias tended to be low and mixed species infections were common, especially where malaria transmission was the highest. Falciparum infection was associated with socio-econiomic status, rural residence and low altitude. Few risk factors were associated with non-falciparum malaria. Conclusions: Asymptomatic falciparum malaria and non-falciparum malaria are common and widely distributed across Rwanda. Continued molecular monitoring of Plasmodium spp. is needed to monitor these threats to malaria control in Africa.

The public health impact and cost-effectiveness of the R21/Matrix-M malaria vaccine: a mathematical modelling study.

BACKGROUND: The R21/Matrix-M vaccine has demonstrated high efficacy against Plasmodium falciparum clinical malaria in children in sub-Saharan Africa. Using trial data, we aimed to estimate the public health impact and cost-effectiveness of vaccine introduction across sub-Saharan Africa. METHODS: We fitted a semi-mechanistic model of the relationship between anti-circumsporozoite protein antibody titres and vaccine efficacy to data from 3 years of follow-up in the phase 2b trial of R21/Matrix-M in Nanoro, Burkina Faso. We validated the model by comparing predicted vaccine efficacy to that observed over 12-18 months in the phase 3 trial. Integrating this framework within a mathematical transmission model, we estimated the cases, malaria deaths, and disability-adjusted life-years (DALYs) averted and cost-effectiveness over a 15-year time horizon across a range of transmission settings in sub-Saharan Africa. Cost-effectiveness was estimated incorporating the cost of vaccine introduction (dose, consumables, and delivery) relative to existing interventions at baseline. We report estimates at a median of 20% parasite prevalence in children aged 2-10 years (PfPR2-10) and ranges from 3% to 65% PfPR2-10. FINDINGS: Anti-circumsporozoite protein antibody titres were found to satisfy the criteria for a surrogate of protection for vaccine efficacy against clinical malaria. Age-based implementation of a four-dose regimen of R21/Matrix-M vaccine was estimated to avert 181 825 (range 38 815-333 491) clinical cases per 100 000 fully vaccinated children in perennial settings and 202 017 (29 868-405 702) clinical cases per 100 000 fully vaccinated children in seasonal settings. Similar estimates were obtained for seasonal or hybrid implementation. Under an assumed vaccine dose price of US$3, the incremental cost per clinical case averted was $7 (range 4-48) in perennial settings and $6 (3-63) in seasonal settings and the incremental cost per DALY averted was $34 (29-139) in perennial settings and $30 (22-172) in seasonal settings, with lower cost-effectiveness ratios in settings with higher PfPR2-10. INTERPRETATION: Introduction of the R21/Matrix-M malaria vaccine could have a substantial public health benefit across sub-Saharan Africa. FUNDING: The Wellcome Trust, the Bill & Melinda Gates Foundation, the UK Medical Research Council, the European and Developing Countries Clinical Trials Partnership 2 and 3, the NIHR Oxford Biomedical Research Centre, and the Serum Institute of India, Open Philanthropy.

Modelling the relative cost-effectiveness of the RTS,S/AS01 malaria vaccine compared to investment in vector control or chemoprophylaxis.

BACKGROUND: The World Health Organization has recommended a 4-dose schedule of the RTS,S/AS01 (RTS,S) vaccine for children in regions of moderate to high P. falciparum transmission. Faced with limited supply and finite resources, global funders and domestic malaria control programs will need to examine the relative cost-effectiveness of RTS,S and identify target areas for vaccine implementation relative to scale-up of existing interventions. METHODS: Using an individual-based mathematical model of P. falciparum, we modelled the cost-effectiveness of RTS,S across a range of settings in sub-Saharan Africa, incorporating various rainfall patterns, insecticide-treated net (ITN) use, treatment coverage, and parasite prevalence bands. We compare age-based and seasonal RTS,S administration to increasing ITN usage, switching to next generation ITNs in settings experiencing insecticide-resistance, and introduction of seasonal malaria chemoprevention (SMC) in areas of seasonal transmission. RESULTS: For RTS,S to be the most cost-effective intervention option considered, the maximum cost per dose was less than $9.30 USD in 90.9% of scenarios. Nearly all (89.8%) values at or above $9.30 USD per dose were in settings with 60% established bed net use and / or with established SMC, and 76.3% were in the highest PfPR2-10 band modelled (40%). Addition of RTS,S to strategies involving 60% ITN use, increased ITN usage or a switch to PBO nets, and SMC, if eligible, still led to significant marginal case reductions, with a median of 2,653 (IQR: 1,741 to 3,966) cases averted per 100,000 people annually, and 82,270 (IQR: 54,034 to 123,105) cases averted per 100,000 fully vaccinated children (receiving at least three doses). CONCLUSIONS: Use of RTS,S results in reductions in malaria cases and deaths even when layered upon existing interventions. When comparing relative cost-effectiveness, scale up of ITNs, introduction of SMC, and switching to new technology nets should be prioritized in eligible settings.

Association between domesticated animal ownership and Plasmodium falciparum parasite prevalence in the Democratic Republic of the Congo: a national cross-sectional study.

BACKGROUND: Domesticated animal ownership is an understudied aspect of the human environment that influences mosquito biting behaviour and malaria transmission, and is a key part of national economies and livelihoods in malaria-endemic regions. In this study, we aimed to understand differences in Plasmodium falciparum prevalence by ownership status of common domesticated animals in DR Congo, where 12% of the world's malaria cases occur and anthropophilic Anopheles gambiae vectors predominate. METHODS: In this cross-sectional study, we used survey data from individuals aged 15-59 years in the most recent (2013-14) DR Congo Demographic and Health Survey and previously performed Plasmodium quantitative real-time PCR (qPCR) to estimate P falciparum prevalence differences by household ownership of cattle; chickens; donkeys, horses, or mules; ducks; goats; sheep; and pigs. We used directed acyclic graphs to consider confounding by age, gender, wealth, modern housing, treated bednet use, agricultural land ownership, province, and rural location. FINDINGS: Of 17 701 participants who had qPCR results and covariate data, 8917 (50·4%) of whom owned a domesticated animal, we observed large differences in malaria prevalence across types of animals owned in both crude and adjusted models. Household chicken ownership was associated with 3·9 (95% CI 0·6 to 7·1) more P falciparum infections per 100 people, whereas cattle ownership was associated with 9·6 (-15·8 to -3·5) fewer P falciparum infections per 100 people, even after accounting for bednet use, wealth, and housing structure. INTERPRETATION: Our finding of a protective association conferred by cattle ownership suggests that zooprophylaxis interventions might have a role in DR Congo, possibly by drawing An gambiae feeding away from humans. Studies of animal husbandry practices and associated mosquito behaviours could reveal opportunities for new malaria interventions. FUNDING: The National Institutes of Health and the Bill & Melinda Gates Foundation. TRANSLATIONS: For the French and Lingala translations of the abstract see Supplementary Materials section.

No evidence of sustained nonzoonotic Plasmodium knowlesi transmission in Malaysia from modelling malaria case data.

Reported incidence of the zoonotic malaria Plasmodium knowlesi has markedly increased across Southeast Asia and threatens malaria elimination. Nonzoonotic transmission of P. knowlesi has been experimentally demonstrated, but it remains unknown whether nonzoonotic transmission is contributing to increases in P. knowlesi cases. Here, we adapt model-based inference methods to estimate RC, individual case reproductive numbers, for P. knowlesi, P. falciparum and P. vivax human cases in Malaysia from 2012-2020 (n = 32,635). Best fitting models for P. knowlesi showed subcritical transmission (RC < 1) consistent with a large reservoir of unobserved infection sources, indicating P. knowlesi remains a primarily zoonotic infection. In contrast, sustained transmission (RC > 1) was estimated historically for P. falciparum and P. vivax, with declines in RC estimates observed over time consistent with local elimination. Together, this suggests sustained nonzoonotic P. knowlesi transmission is highly unlikely and that new approaches are urgently needed to control spillover risks.

RTS,S vaccination is associated with reduced parasitemia and anemia among children diagnosed with malaria in the outpatient department of a district hospital in rural Malawi.

The RTS,S/AS01 malaria vaccine was recently approved by the World Health Organization, but real-world effectiveness is still being evaluated. We measured hemoglobin concentration and parasite density in vaccinated and unvaccinated children who had been diagnosed with malaria by rapid diagnostic test (mRDT) in the outpatient department of a rural hospital in Malawi. Considering all mRDT positive participants, the mean hemoglobin concentration among unvaccinated participants was 9.58 g/dL. There was improvement to 9.82 g/dL and 10.36 g/dL in the 1 or 2 dose group (p = 0.6) and the 3 or 4 dose group (p = 0.0007), respectively. Among a microscopy positive subset of participants, mean hemoglobin concentration of unvaccinated participants was 9.55 g/dL with improvement to 9.82 g/dL in the 1 or 2 dose group (p = 0.6) and 10.41 g/dL in the 3 or 4 dose group (p = 0.003). Mean parasite density also decreased from 115,154 parasites/µL in unvaccinated children to 87,754 parasites/µL in children who had received at least one dose of RTS,S (p = 0.04). In this study population, vaccination was associated with significant improvements in both hemoglobin concentration and parasite density in the setting of real-world administration of the RTS,S/AS01 vaccine.

Low Complexity of Infection Is Associated With Molecular Persistence of Plasmodium falciparum in Kenya and Tanzania.

Background: Plasmodium falciparum resistance to artemisinin-based combination therapies (ACTs) is a threat to malaria elimination. ACT-resistance in Asia raises concerns for emergence of resistance in Africa. While most data show high efficacy of ACT regimens in Africa, there have been reports describing declining efficacy, as measured by both clinical failure and prolonged parasite clearance times. Methods: Three hundred children aged 2-10 years with uncomplicated P. falciparum infection were enrolled in Kenya and Tanzania after receiving treatment with artemether-lumefantrine. Blood samples were taken at 0, 24, 48, and 72 h, and weekly thereafter until 28 days post-treatment. Parasite and host genetics were assessed, as well as clinical, behavioral, and environmental characteristics, and host anti-malarial serologic response. Results: While there was a broad range of clearance rates at both sites, 85% and 96% of Kenyan and Tanzanian samples, respectively, were qPCR-positive but microscopy-negative at 72 h post-treatment. A greater complexity of infection (COI) was negatively associated with qPCR-detectable parasitemia at 72 h (OR: 0.70, 95% CI: 0.53-0.94), and a greater baseline parasitemia was marginally associated with qPCR-detectable parasitemia (1,000 parasites/uL change, OR: 1.02, 95% CI: 1.01-1.03). Demographic, serological, and host genotyping characteristics showed no association with qPCR-detectable parasitemia at 72 h. Parasite haplotype-specific clearance slopes were grouped around the mean with no association detected between specific haplotypes and slower clearance rates. Conclusions: Identifying risk factors for slow clearing P. falciparum infections, such as COI, are essential for ongoing surveillance of ACT treatment failure in Kenya, Tanzania, and more broadly in sub-Saharan Africa.

Engaging in cognitive activities, aging, and mild cognitive impairment: a population-based study.

The authors investigated whether engaging in cognitive activities is associated with aging and mild cognitive impairment (MCI) in a cross-sectional study derived from an ongoing population-based study of normal cognitive aging and MCI in Olmsted County, MN. A random sample of 1,321 study participants ages 70 to 89 (N=1,124 cognitively normal persons, and N=197 subjects with MCI) were interviewed about the frequency of cognitive activities carried out in late life (within 1 year of the date of interview). Computer activities; craft activities, such as knitting, quilting, etc.; playing games; and reading books were associated with decreased odds of having MCI. Social activities, such as traveling, were marginally significant. Even though the point-estimates for reading magazines, playing music, artistic activities, and group activities were associated with reduced odds of having MCI, none of these reached statistical significance. The equally high prevalence of reading newspapers in both groups yielded no significant between-group difference.

Prospective Newborn Screening for Sickle Cell Disease and Other Inherited Blood Disorders in Central Malawi.

Objectives: Newborn screening in the United States and Europe allows early identification of congenital disorders but does not yet exist in most low-resource settings, especially in sub-Saharan Africa. Newborn screening can identify multiple inherited hematological disorders, but feasibility and effectiveness for Africa are not fully determined. Methods: Surplus dried blood spot collected in Central Malawi through the HIV Early Infant Diagnosis surveillance program were repurposed and tested by isoelectric focusing for sickle cell disease and trait. Additional genetic testing identified G6PD deficiency and alpha thalassemia. Results: Testing of 10,529 cards revealed an overall sickle cell trait prevalence of 7.0% (range 3.9-9.7% by district); 10 of 14 infants identified with sickle cell disease (prevalence 0.1%) were located and received care at a specialized clinic. Subsequent testing of 1,329 randomly selected cards identified alpha thalassemia trait in 45.7% of samples, and G6PD deficiency in 20.4% of males and 3.4% of females, with 29.0% of females as heterozygous carriers. Conclusion: Inherited hematological disorders are common in Central Malawi; early identification through newborn screening can improve clinical outcomes and should be supported throughout Africa.