American Journal of Tropical Medicine and Hygiene最新文献

In an open randomized controlled trial, we compared one vial (10 mL) to two vials (20 mL) of EchiTAb-plus-ICP (EPI) antivenom among children with systemic carpet viper (Echis romani) envenoming of moderate severity in northeastern Nigeria. Systemic envenoming, presenting with incoagulable blood, was diagnosed using the 20-minute whole blood clotting test (20WBCT). Eligible patients with positive 20WBCT whose guardians assented were recruited and randomly allocated to receive either one vial or two vials of EPI administered either as a bolus or as a slow continuous infusion. The primary outcome was permanent restoration of blood coagulability 6 hours after the start of treatment, assessed by the 20WBCT and repeated at 6, 12, 24, and 48 hours after treatment. Secondary outcomes were the incidences of early adverse reactions to antivenom treatment. Initial doses permanently restored blood coagulability at 6 hours in 34/39 (87.2%) of those treated with one vial and 39/41 (95.1%) of those treated with two vials of EPI (P = 0.258). However, the proportion with permanent restoration of clotting at 6 hours among patients randomized to bolus administration was 41 of 42 (97.6%) patients compared with 32 of 38 (84.2%) patients randomized to slow infusion of EPI antivenom (P = 0.049); however, the difference was not sustained through the remaining time points. There was no difference in early adverse reactions between those treated with the two different doses or modes of delivery. We conclude that the one-vial dose compared favorably to two vials of EPI antivenom with regards to effectiveness and safety among children with carpet viper envenoming of moderate severity in Nigeria.

Hand, foot, and mouth disease (HFMD) is a common viral infection primarily affecting children. It causes vesicles on the skin and inside the mouth. Although most cases get better on their own, severe cases can lead to complications such as brain stem encephalitis, meningoencephalitis, acute flaccid paralysis, and pulmonary edema. Hand, foot, and mouth disease is caused by various enteroviruses, with enterovirus A71 (EV-A71) and coxsackievirus A16 being the most common. However, recent studies have shown a shift in the molecular epidemiology of HFMD-causing pathogens, with coxsackievirus A6 and coxsackievirus A10 causing more infections. In addition, extensive recombination events have been identified among enterovirus strains, which may have a role in faster evolution and extinction of dominant enterovirus serotypes. Other strains of enterovirus can also cause severe complications, and there has been an increase in mortality associated with brain stem encephalitis in children under 3 years of age and teenagers. Currently, there are no effective antiviral therapies available to treat enterovirus infections. Vaccines against EV-A71 have been approved and are now used in mainland China. Studying the changing epidemiology of HFMD pathogens and the evolution patterns of its causative agents is crucial in developing effective prevention and control strategies. Increased interest in the molecular epidemiology of HFMD causative agents has led to a better understanding of the critical drivers of HFMD outbreaks, which can inform efforts to prevent and control the disease.

The dengue crisis in the Latin American region is currently intensifying, exacerbated by heavy rains, widespread flooding, and the onset of the El Niño-Southern Oscillation. The indirect consequences of the COVID-19 pandemic, which weakened healthcare systems, have further compounded the situation. Comparing the first 15 weeks of 2023 with the same period in 2024, we observed a significant average increase of 600% in the number of new cases. This translates to a 536% rise in the composite rate per 100,000 inhabitants across all countries. Brazil experienced a staggering surge from 1,425,000 cases in the initial 15 weeks of 2023 to 5,177,989 cases in the corresponding period of 2024. Similarly, Paraguay witnessed a notable escalation, with cases soaring from 12,497 in 2023 to more than 240,000 thus far in 2024, marking an increase of more than 1,825%. Bolivia, however, witnessed a reduction in cases, though the cause remains unclear. Urgent action is imperative to address this escalating crisis. Strengthening surveillance systems, enhancing vector control programs, and implementing effective public health campaigns are critical. Immediate and coordinated action by regional governments and health authorities is essential to mitigate the growing dengue crisis and safeguard public health in the region.

The Hajj is an annual mass gathering of people in Makkah, Saudi Arabia. Respiratory infections are common due to their potential for rapid spread in crowded settings. There is a lack of data regarding the effectiveness of face masks in preventing respiratory tract infections (RTIs), specifically during Hajj. We systematically searched PubMed, Scopus, Web of Science, and Cochrane Central Register of Controlled Trials until July 3, 2023 for studies comparing the incidence or prevalence of RTIs in those who used any face mask during Hajj compared with no mask. Risk ratio (RRs) and 95% CIs were calculated using either a fixed or random-effect model, depending on the heterogeneity. A comprehensive analysis encompassed 10 studies involving 5007 participants. The overall RR favored wearing masks over not wearing masks regarding the incidence of RTIs; however, the difference was not statistically significant (RR = 0.78; 95% CI = 0.55-1.10; P = 0.16). A significantly lower incidence of RTIs was found in those wearing masks most of the time versus intermittently (RR = 0.59; 95% CI = [0.38-0.94; P = 0.02). In subgroup analyses, there was no difference between wearing masks and not wearing masks across different study designs (cohort/case-control), different groups (pilgrims/healthcare workers), and different years of Hajj, except from 2000 to 2008, when there was a significant difference favoring wearing face masks. This meta-analysis found wearing masks most of the time was associated with significantly lower risk of RTIs than wearing it intermittently.

Powassan virus lineage II or deer tick virus (DTV) is a rare but increasingly reported human infection in the United States transmitted by Ixodes scapularis ticks. The virus is thought to be maintained in environmental foci that are optimal for tick and vertebrate reservoirs, but details on DTV ecology are poorly understood. We investigated DTV tick infection rates and reservoir host abundance in a focus of consistent DTV activity in Maine, USA. Host and tick abundance, vegetation, and microclimate conditions were measured in three forest sites representing increasing invasive understory infestation. Sites were selected representing native understory, mixed vegetation with some invasive Japanese barberry (Berberis thunbergii), and a highly invasive site dominated by Japanese barberry. Japanese barberry in the mixed vegetation site averaged 1 m in height with space between plants, whereas the highly invasive site had impenetrable Japanese barberry over 1.5 m. The DTV infection rate was greater in the highly invasive site. Density of I. scapularis ticks were significantly lower in the native forest site, and no DTV was found. Another feature of the DTV focus was more stable humid microclimate throughout the year compared with the other sites and a nearby continuous section of forest, consistent with reports from Connecticut, USA. We conclude that invasive Japanese barberry stands provide favorable and consistent microclimate conditions to maintain high DTV infection rates annually among questing I. scapularis ticks. Understanding environmental and landscape features that support high infection rates could lead to the identification of high-risk habitats for contracting DTV.

Providing and improving the care of patients suffering from lymphedema remains an essential goal for the clinical management of populations affected by lymphatic filariasis. Although the Essential Package of Care (EPC) recommended by the WHO leads to important positive benefits for many of these lymphedema patients, it is important to continue to address the challenges that remain both in quantifying these effects and in ensuring optimal care. This report, based on the authors' scientific and field experience, focuses on the impact and significance of lymphedema, its clinical presentation, current treatment approaches, and the importance of lymphedema care to the Global Program to Eliminate Lymphatic Filariasis. It emphasizes specific practical issues related to managing lymphedema, such as the importance of beginning treatment in the condition's early stages and the development of effective approaches to assess patients' progress toward improving both their clinical status and their overall quality of life. Priorities for research are also examined, particularly the need for tools to identify patients and to assess disease burden in endemic communities, the creation of EPC accessibility to as many patients as possible (i.e., targeting 100% "geographic coverage" of care), and the empowerment of patients to ensure the sustainability, and ultimately the provision of care from sectors of the national public health systems of endemic countries.

Improving the visibility and global coordination of malaria surveillance and data quality improvement initiatives is required to optimize sharing of best practices, tools, and approaches and to promote efficient, effective, and equitable distribution of resources. With these aims in mind, Rollback Malaria's Surveillance, Monitoring and Evaluation Working Group established the Surveillance Practice and Data Quality Committee in May 2021. As a priority initiative, the committee conducted a landscape analysis of implementing partners' (IPs') malaria surveillance-related projects. A questionnaire that included questions on current project objectives, activities, geographic scope, and lessons learned was distributed among committee members and other IPs. Three years since its inception, information has been submitted regarding 49 projects by 25 IPs and funded by 17 donors. To present and share the landscaping results, an interactive dashboard was published to the Rollback Malaria's Global Malaria Dashboard website (endmalaria.org) in March 2021. It is the first time that multiple stakeholders have shared such information regarding surveillance projects.

Macrolide antibiotics are recommended for the treatment of pneumococcal pneumonia and invasive pneumococcal disease (IPD). Prior to 2000, ∼10% of Streptococcus pneumoniae strains isolated from IPD cases in Latin American countries were resistant to macrolides. The mechanism of resistance to macrolides was associated mainly with the efflux pump known as the macrolide efflux genetic assembly, since most pneumococcal strains carried the mef(A/E) gene, whereas <6% strains carried both the methylase gene ermB and mef(A/E). In the first decade of this century, a significant increase in the prevalence of macrolide resistance was observed in pneumococcal strains in both Mexico and Peru. Approximately 30% of S. pneumoniae strains in these countries were already resistant to erythromycin, while the prevalence in Colombia, Argentina, and Brazil remained below 10%. During the last decade, we have been experiencing a worrisome increase in pneumococcal strains carrying resistance to macrolides, with a prevalence of up to 80% for resistance to erythromycin. The mechanism for disseminating macrolide resistance has evolved. Currently, more than 55% of invasive S. pneumoniae macrolide-resistant strains carry both the ermB and the mef(A/E)/mel genes. Lessons learned from the current macrolide resistance crisis in Latin America can inform interventions in other regions.

Parasites are generally associated with lower income countries in tropical and subtropical areas. Still, they are also prevalent in low-income communities in the southern United States. Studies characterizing the epidemiology of parasites in the United States are limited, resulting in little comprehensive understanding of the problem. This study investigated the environmental contamination of parasites in the southern United States by determining each parasite's contamination rate and burden in five low-income communities. A total of 499 soil samples of approximately 50 g were collected from public parks and private residences in Alabama, Louisiana, Mississippi, South Carolina, and Texas. A technique using parasite floatation, filtration, and bead-beating was applied to dirt samples to concentrate and extract parasite DNA from samples and detected via multiparallel quantitative polymerase chain reaction (qPCR). qPCR detected total sample contamination of Blastocystis spp. (19.03%), Toxocara cati (6.01%), Toxocara canis (3.61%), Strongyloides stercoralis (2.00%), Trichuris trichiura (1.80%), Ancylostoma duodenale (1.42%), Giardia intestinalis (1.40%), Cryptosporidium spp. (1.01%), Entamoeba histolytica (0.20%), and Necator americanus (0.20%). The remaining samples had no parasitic contamination. Overall parasite contamination rates varied significantly between communities: western Mississippi (46.88%), southwestern Alabama (39.62%), northeastern Louisiana (27.93%), southwestern South Carolina (27.93%), and south Texas (6.93%) (P <0.0001). T. cati DNA burdens were more significant in communities with higher poverty rates, including northeastern Louisiana (50.57%) and western Mississippi (49.60%) compared with southwestern Alabama (30.05%) and southwestern South Carolina (25.01%) (P = 0.0011). This study demonstrates the environmental contamination of parasites and their relationship with high poverty rates in communities in the southern United States.