American Journal of Tropical Medicine and Hygiene最新文献

Azithromycin mass drug administration (MDA) for 1- to 59-month-olds reduces child mortality. However, guidelines restrict eligibility to 1- to 11-month-olds because of concerns about antimicrobial resistance. This cluster-randomized implementation trial was conducted in parallel with a larger efficacy trial and compared implementation outcomes between these approaches. Rural communities in Niger were randomly assigned to receive biannual azithromycin MDA for either 1- to 59-month-olds or 1- to 11-month-olds over 1 year. The primary outcome was the community-level cost per dose delivered. Secondary outcomes included reach (coverage), as well as acceptability, appropriateness, and feasibility according to participants and providers. In November 2020, 40 eligible communities were randomly assigned to each arm, with 37 communities in the 1- to 59-month arm and 39 communities in the 1- to 11-month arm contributing to analyses. The mean cost per dose delivered was $6.50 lower (95% CI -$10.40 to -$3.70; P-value <0.001) in the 1- to 59-month arm ($1.60; 95% CI $1.00 to $2.30) compared with the 1- to 11-month arm ($8.20; 95% CI $7.60 to $8.80). Treatment coverage was similar by arm and exceeded 90% in both distributions. More caregivers in the 1- to 59-month arm found the intervention acceptable (mean difference 4.2%; 95% CI 0 to 8.4%; P-value 0.04) and appropriate (3.4%; 95% CI 0.1 to 6.8%; P-value 0.04) compared with the 1- to 11-month arm. When combining arms, all groups indicated that including 1- to 59-month-olds was more acceptable, appropriate, and feasible than restricting to 1- to 11-month-olds. No serious adverse events were reported. Overall, including 1- to 59-month-olds resulted in a lower cost per dose delivered than restricting to 1- to 11-month-olds. Community groups perceived both interventions to be acceptable, appropriate, and feasible, but they strongly preferred the 1- to 59-month treatment.

Malaysia's malaria rate has declined but remains a public health concern, with limited investigations into malaria and coinfections with soil-transmitted helminth (STH) infections. A cross-sectional study using convenience sampling in Orang Asli villages enrolled 437 villagers aged 1-83 years based on their willingness to participate. Blood samples were tested microscopically for malaria, followed by nested polymerase chain reaction (PCR), and stool samples were screened microscopically for STH eggs. Body temperature, demographic, and socioeconomic data were collected. Malaria parasite was detectable only via PCR, with a 15.3% prevalence, indicating submicroscopic malaria parasitemia; none of the positive cases presented fever. The identified species included Plasmodium vivax (8.7%), Plasmodium cynomolgi (5.5%), Plasmodium knowlesi (4.3%), Plasmodium falciparum (1.8%), Plasmodium inui (0.2%), and Plasmodium malariae (0.2%). Females had significantly higher rates of submicroscopic malaria parasitemia (19.6%) compared with males (9.3%, P = 0.003). STH infections were highly prevalent (71.4%), with Trichuris trichiura (65.2%), Ascaris lumbricoides (35.0%), and hookworm (14.6%). STH infection was associated with age (P <0.001), peaking in individuals aged 10-19 years (86.2%) and 1-9 years (83.0%), as well as with students (84.3% versus 60.8% in employed and 60.3% in unemployed; P <0.001) and low-income households (76.4% versus 61.7% in higher-income households; P = 0.002). Submicroscopic malaria parasitemia and STH coinfections were present in 8.9% of participants, with higher rates in low-income households (12.6% versus 5.2% in higher-income, P = 0.010). The Negrito tribe exhibited the highest prevalence of submicroscopic malaria parasitemia, STH, and coinfections (P <0.05). This study highlights the need for integrated malaria and STH control strategies, particularly for the Negrito tribe.

A malaria control program established in 2004 on Bioko Island, Equatorial Guinea, achieved significant reductions in malaria prevalence; however, progress subsequently stalled, leading to a proposal to develop and implement a highly effective malaria vaccine to increase impact. After conducting clinical trials of Sanaria® (Rockville, MD) Plasmodium falciparum (P. falciparum) sporozite vaccines against P. falciparum malaria, which demonstrated safety and efficacy, a larger phase 3 trial was planned to support vaccine licensure for specific target populations and eventual island-wide malaria elimination. The Equatorial Guinea Pilot Study for Recruitment, Screening and Participant Registry (EGRESPAR) assessed the health status of the target population and generated a registry of eligible children and adults. Households in areas with malaria prevalence ≥15% were randomly selected, aiming to register 2,100 healthy Equatoguineans divided equally into age groups of 1.5-9, 10-17, and 18-50 years. A total of 6,493 individuals from 1,807 households, who considered themselves or their children to be healthy, completed questionnaires; 2,021 were screened using phase 3 enrollment criteria, 643 were excluded, and 1,378 were entered into the registry. Among those screened, 13.6% had Plasmodium, 1.8% had Loa loa, 4.8% had hepatitis B, 0.5% had hepatitis C, and 2.1% had HIV. Adults were twice as likely to have clinically relevant medical conditions, such as obesity, hypertension, or diabetes, meeting exclusion criteria compared to children. In conclusion, there was a significant prevalence of infections and chronic medical conditions among Bioko Island residents who considered themselves or their children to be healthy and interested in clinical research participation, particularly in adults. The EGRESPAR successfully generated a registry to support the initiation of a large-scale phase 3 vaccine trial.

Eastern equine encephalomyelitis virus (EEEV) is endemic in Michigan, showing an upsurge in human cases and in infections of white-tailed deer, horses, and other animals in the past decade (2010-2020). However, blood-host associations of the enzootic mosquito vector Culiseta melanura in the Great Lakes region are poorly known compared with other better-studied regions. Vertebrate sources of blood meals of Cs. melanura collected from resting boxes were determined through sequencing of the mitochondrial cytochrome B gene generated from polymerase chain reaction. Thirty-six unique avian species were detected in the samples, and 42% of the blood meals originated from only two species (American robin and northern cardinal). This result shows that although the Cs. melanura population investigated here used a wide range of avian hosts, American robin and northern cardinal are the main hosts in southwestern Michigan.

We present a case of a 46-year-old male with disseminated melioidosis. He initially presented with primary bacteremia but eventually developed a recrudescent infection characterized by meningo-rhombencephalitis, as well as pulmonary and splenic abscesses. This was attributed to the emergence of carbapenem resistance, which developed while he was receiving parenteral antibiotic therapy. The patient eventually improved after switching his antibiotics to a combination of ceftazidime and trimethoprim-sulfamethoxazole. The development of carbapenem resistance in Burkholderia pseudomallei during therapy is rare but may be attributed to mutations resulting in the overexpression of efflux pumps. Combination therapy may play a role in such cases by limiting the emergence of antibiotic resistance.

Water quality assessments are critical for ensuring timely responses to water-related concerns, particularly in low-resource areas with limited water, sanitation, and hygiene (WASH) infrastructure. In collaboration with the Belize Ministry of Health and Wellness and the Ministry of Education, Culture, Science and Technology, we conducted a survey on WASH infrastructure and resources among 221 schools. We identified 65 schools across all six districts of Belize for water quality testing. Among these 65 schools, 83% had at least one water sample that did not meet the WHO's recommended free chlorine residual level for drinking water. Additionally, coliforms and Escherichia coli were detected in at least one drinking or handwashing water sample from 43 (66%) and 14 (22%) schools, respectively. These findings underscore the importance of routine water quality testing in schools to inform timely public health responses.

Acute kidney injury (AKI) remains a common cause of preventable death in low-resource settings because of cost and lack of dialysis access. AKI occurs in 24-59% of children with severe malaria, and when severe malaria-associated acute kidney injury (SM-AKI) is complicated by hyperkalemia, mortality approaches 40%. Treatment of these children with severe anemia becomes challenging as packed red blood cells (pRBCs) have high potassium (K+) loads. We describe a protocol using the novel manual single-lumen alternating microbatch (mSLAMB) dialysis system to deplete pRBCs of K+, hypothesizing that this system can decrease K+ >80% in 20 minutes. Herein, we ran pRBC aliquots through the mSLAMB system using diffusive clearance. Three cycles were completed in each of four experiments. K+ was measured at baseline and after every cycle to calculate K+ reduction. Active ultrafiltration was performed to control net volumes, assessed as percentage of blood volume reduction and hematocrit rise. We reduced K+ in pRBC aliquots by a median of 93.2% (interquartile range [IQR], 89.9-95.1) in a median of 20.5 minutes (IQR, 17.8-23.1) per experiment. Greatest median K+ reduction occurred in cycle 1 (80.9%; IQR, 80.8-80.9), with minimal additional clearance achieved by cycle 3. Median hematocrit rise at experiment conclusion was 2.5% (IQR, 1.8-3.3). We conclude that mSLAMB dialysis consistently and effectively removed >80% of K+ from pRBCs in just over 20 minutes and facilitated volume control. Further studies are assessing transfusion risks in children with SM-AKI and hyperkalemia as this technique may allow for safer resuscitation.

The Mycobacterium tuberculosis complex (MTBC), the causative agent of tuberculosis (TB), remains a significant global health challenge, with an estimated 10.8 million cases diagnosed and 1.25 million deaths in 2023, according to the WHO. In this context, enhancing TB case detection using more sensitive diagnostic methods is essential. Here, we compared the performance of two commercial real-time polymerase chain reaction (PCR) kits with the reference standards of smear microscopy, culture, and Gene Xpert. By analyzing 402 clinical specimens, we found that conventional DNA extraction, followed by real-time PCR, using either of the two commercial kits provided the highest sensitivity for detecting MTBC. Positivity values of 48.98-60.07% and 50.34-53.24% were obtained with the commercial kits "VIASURE MTBC + non tuberculous mycobacterias (NTM) Real-Time PCR Detection Kit" (Certest, Spain) and "ANYPLEX™ MTB/NTM Real-Time Detection Kit" (Seegene, South Korea), respectively. In contrast, the reference standards yielded positivity values of 14.75% (smear microscopy), 32.65% (culture), and 28.95% (GeneXpert assay). These alternative methods should be considered as valuable tools to strengthen TB control and prevention strategy.