American Journal of Tropical Medicine and Hygiene最新文献

Identifying viable infections in neurocysticercosis (NCC) is crucial for treatment. Neuroimaging is the primary diagnostic tool, but it is not widely available. Moreover, in many cases, imaging diagnosis is not pathognomonic and requires serological confirmation. The serological assay of choice, enzyme-linked immunoelectrotransfer blot using lentil lectin-purified glycoprotein (LLGP-EITB) Taenia solium antigens to detect specific antibodies, exhibits high predictive values for the presence of viable NCC when the results are positive for multiple (>3) antibody bands; it also exhibits high predictive values for the absence of viable infection when the results are negative or the test reacts to a single antibody band. However, its interpretation in terms of viable infection is limited in cases with two or three positive bands (intermediate results), which occur in one-quarter of patients with NCC. The quantification of specific antibodies could allow for the identification of viable infections. Using a multi-antigen, quantitative multiplex bead assay, antibody levels were measured against Taenia solium proteins rGP50, rT24H, and sTs18var1 in 94 patients with intermediate LLGP-EITB results. The antibody-to-rT24H (25.96 versus 5.49; P = 0.0048) and antibody-to-sTs18var1 ratios (3.62 versus 1.37; P = 0.0083) were higher in subjects with viable cysticerci than in controls. Patients with high antibody levels against the proteins rT24H and sTs18var1 were 5.4 times more likely to have a viable infection than those with low antibody levels. The quantification of antibodies against rT24H and sTs18var1 can help define a viable NCC infection.

Virus-associated infections remain a major burden of childhood morbidity and mortality in sub-Saharan Africa. This exploratory, population-based study used programmable phage immunoprecipitation and sequencing to simultaneously evaluate the antibody response to multiple viruses in dried blood spots from 251 children aged 12 to 59 months who were previously enrolled in the Community Health with Azithromycin Treatment trial conducted in Burkina Faso from 2019 to 2023. Linear mixed effects models, with cluster as the random effect, were used to examine associations between viral antibody response and age, sex, time points (before and after the onset of the severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2] pandemic), and azithromycin mass drug administration (MDA). Sero-reactivity to SARS-CoV-2 was negatively correlated with age in months (β coefficient: -1.43; 95% CI: -2.03 to -0.84; Padj <0.001), but not to sex (β coefficient: 4.63; 95% CI: -11.90 to 21.17; Padj = 0.58) or azithromycin MDA (β coefficient: -9.43; 95% CI: -27.56 to 8.71; Padj = 0.45). Immunoreactivity to the respiratory syncytial virus (RSV) did not appear to be altered after the emergence of SARS-CoV-2 (β coefficient: 39.26; 95% CI: -0.20 to 78.72; Padj = 0.31). In addition, no detectable differences in the sero-reactivity to poliovirus 1 were observed with azithromycin MDA (β coefficient: 17.86; 95% CI: -25.35 to 61.07; Padj = 0.82). Although an association was observed between sero-reactivity to SARS-CoV-2 and age, the emergence of SARS-CoV-2 did not appear to alter the antibody response of preschool children in Burkina Faso to RSV or poliovirus vaccine uptake. Longitudinal studies in other at-risk populations in sub-Saharan Africa may improve mechanistic understanding and preventive strategies to decrease childhood morbidity.

Although maternal influenza vaccination can prevent influenza morbidity and mortality, data are limited on vaccine efficacy/effectiveness against severe disease in low- and middle-income countries (LMICs) at the community level. We evaluated the impact of maternal influenza vaccination on maternal influenza disease severity across seasons in a rural subtropical area in South Asia by analyzing data from a vaccine clinical trial conducted between 2011 and 2014 in Sarlahi District, Nepal. Participants were randomized 1:1 to trivalent seasonal influenza vaccine or saline placebo and followed through 180 days postpartum. Weekly household-based active respiratory surveillance was conducted; if participants reported fever and respiratory symptoms, a midnasal swab was collected and tested for influenza using reverse transcription polymerase chain reaction. Among 3,693 participants (n = 1,847 vaccine; n = 1,846 placebo), we detected 75 influenza illness episodes, including 40 with care seeking and 22 with fever for more than 3 days. Using proportional hazards regression, maternal influenza vaccination reduced the estimated hazard of influenza-associated care-seeking visits and fever for more than 3 days by 36% and 21%, respectively, compared with placebo; however, these differences were not statistically significant. The estimated numbers needed to vaccinate to prevent one influenza illness with care seeking and fever for more than 3 days were 224 and 785, respectively, at 270 days postvaccination. These findings suggest that maternal immunization may reduce the risk of moderate influenza illness among pregnant/postpartum individuals in LMICs, particularly in rural areas where access to care is limited.

Angiostrongylus cantonensis meningitis is a parasitic disease of the central nervous system. Its diagnosis is challenging because it shows nonspecific clinical signs. In Mayotte, France, cases are reported annually, mainly in children. The key indicator is the presence of eosinophilic meningitis. We report the case of an 11-month-old infant seen in Mayotte with altered consciousness and fever. Lumbar puncture revealed an elevated white blood cell count in the cerebrospinal fluid (CSF) with a 100% lymphocytic formula. A brain computed tomography suggested tuberculosis but did not exclude parasitic infection. Blood tests showed significant eosinophilia. Empirical treatment of tuberculous meningitis was started. A second lumbar puncture showed 13% eosinophils, and the polymerase chain reaction for A. cantonensis was positive. This atypical case of lymphocytic meningitis could have caused a diagnostic error. In cases with strong clinical suspicion and absence of initial eosinophilic meningitis, it is essential to repeat CSF analysis and consider antiparasitic therapy.

The efficacy, best dosage, and safety of liposomal amphotericin B (LAB) in the treatment of cutaneous leishmaniasis (CL) caused by Leishmania braziliensis in elderly patients was determined by a randomized, controlled trial. We selected 28 patients of both sexes age 60 years old or older with CL diagnosis confirmed by detection of L. braziliensis DNA. The groups were treated with different total doses of LAB (group 1: 12 mg/kg; group 2: 18 mg/kg; and group 3: 24 mg/kg). Clinical and laboratory evaluations were carried out during a period of 180 days (day 0, day 15, day 30, day 60, day 90, and day 180). The highest cure rate (89%) was in group 3 (differences were not statistically significant) along with the lowest incidence of side effects (11%), suggesting that 24 mg/kg is the best dose of LAB to treat CL in elderly patients.

Although acute rheumatic fever (ARF) is a preventable condition, it continues to be diagnosed in Far North Queensland, Australia. Enhanced primary prevention is necessary to reduce the local burden of ARF and rheumatic heart disease. In this retrospective clinical audit, all cases of definite ARF in the remote Torres Strait and Cape York region of Far North Queensland between January 2020 and December 2024 were examined. Clinical records were reviewed to identify and characterize any healthcare presentations of individuals during the 6 weeks preceding their ARF diagnosis. Of 67 individuals with definite ARF 65 (97%) identified as First Nations Australians; 43/67 (64%) did not present for any healthcare in the 6 weeks preceding their diagnosis; and a further 10/67 (15%) presented for healthcare that was unrelated to group A Streptococcus (Strep A) infection. Overall, a possible Strep A infection (skin infection or sore throat) was identified in 14/67 (21%) patients; 9/67 (13%) patients presented with skin infections, and 5/67 (7%) presented with sore throats. Of these, 5/14 (36%) received appropriate antibiotic treatment. Most individuals with definite ARF in this remote region of Australia do not present for healthcare before their diagnosis; however, there remain opportunities for the primary prevention of ARF among those who do. Culturally considered health promotion, opportunistic screening, and improved recognition and treatment of Strep A infection are critical for reducing ARF incidence in this region of Australia. It is also important to define the contribution of asymptomatic Strep A infections to the pathogenesis of ARF.

Infections from Shigella spp./enteroinvasive Escherichia coli (EIEC) are considered leading causes of diarrheal disease globally. However, there is a notable paucity of studies from Caribbean nations to guide regional public health interventions. A case-control study was conducted as part of a cross-sectional healthcare study in Haiti. Households were identified using a geospatially randomized method, and families with children under 5 years of age were consented and enrolled. Rectal swabs from child participants were tested for Shigella spp./EIEC via real-time polymerase chain reaction testing using the invasion plasmid antigen H gene target. Two case definitions were used: "diarrheal symptom" (DS) cases were defined as those reporting DSs ≤7 days ago; "acute diarrhea" (AD) cases were defined as those who also presented with ≥3 loose stools in the past 24 hours and onset <7 days ago. A total of 568 households were enrolled, and samples from 732 children were analyzed. The rates of Shigella spp./EIEC detection were 11% (22/193) and 6% (33/539) among DS cases and controls, respectively, and 19% (8/43) and 7% (47/689) among AD cases and controls, respectively. Shigella spp./EIEC was attributed to DS in 6% (95% CI: 0.4% to 11%) of cases and AD in 13% (95% CI: 0% to 25%) of cases. The adjusted odds of having DS increased by 84% (adjusted odds ratio [aOR] = 1.84; 95% CI: 1.02 to 3.27) and AD increased by 183% (aOR = 2.83; 95% CI: 1.14 to 6.36) when Shigella spp./EIEC was detected. The rates of bloody diarrhea were minimal (<1%; 6/732). In the present case-control study, the detection of Shigella spp./EIEC was common and attributed to symptomatic disease. These results align with previous global health studies. Shigella spp./EIEC represent an important public health target for intervention once the security situation improves in Haiti.

Scrub typhus, caused by Orientia tsutsugamushi, is a common endemic vector-borne disease in Asia that can lead to a range of systemic complications, including the rare but potentially life-threatening manifestation of acute pancreatitis. We conducted a systematic review of all reported cases of scrub typhus-associated acute pancreatitis from 1943 to 2024 using PubMed, including English, Japanese, and Chinese literature, and analyzed a total of 14 cases, including one newly identified case at our institution. Diagnostic criteria were based on compatible clinical features, elevated pancreatic enzymes, and characteristic imaging findings. The median age of patients was 47 years (range 22-75), with 69.2% of patients being male. The most frequent clinical manifestations were fever (100%), abdominal pain (92.3%), and thrombocytopenia (30.8%). Over one-third of the patients developed multiple organ dysfunction syndrome (MODS) or shock, and the mortality rate was 23.1%, with all fatalities occurring in patients with MODS. Most patients received doxycycline or azithromycin along with supportive care. The newly reported case presented with rapidly progressive pancreatitis requiring intensive care and multiple organ support, but the patient eventually recovered. These findings highlight that acute pancreatitis is an underrecognized yet severe complication of scrub typhus, often associated with poor outcomes when MODS is present. Clinicians in endemic regions should consider pancreatitis in the differential diagnoses when evaluating scrub typhus patients with abdominal symptoms or systemic inflammation. Prompt recognition and timely, aggressive management may improve survival and reduce complications in affected patients.

The objective of this study was to compare coronavirus disease 2019 (COVID-19) and influenza among US active-component service members (ACSMs) stationed at military installations near the US-Mexico border (Arizona, California, New Mexico, and Texas). A retrospective cohort study was conducted to assess diagnoses of influenza (2020-2024) and COVID-19 (2020-2023). Incidence rate ratios (IRRs) comparing influenza and COVID-19 at border and non-border locations were calculated for laboratory-confirmed and/or symptom-based encounter diagnoses. Forty-five percent of ACSMs included in the influenza (N = 650,505) and COVID-19 (N = 660,333) analyses were near the border. There was no statistically significant increase of either COVID-19 or influenza incidence among ACSMs stationed near the border compared with those located elsewhere in the same states. A statistically significantly reduced adjusted IRR (aIRR) of laboratory-confirmed influenza (aIRR: 0.93; 95% CI: 0.89, 0.98) and COVID-19 (aIRR: 0.97; 95%: CI: 0.96, 0.99) was observed among ACSMs stationed near the border compared with those located elsewhere in the same states for all states combined for the entire study period. Similarly, significantly lower aIRRs were observed for all diagnoses (laboratory-confirmed or symptoms-based encounter) of influenza (aIRR: 0.81; 95% CI:0.80, 0.82) among ACSMs near the border compared with ACSMs not near the border for all states combined for the entire duration of the study. However, incidence rates of COVID-19 and influenza varied across some specific states and time periods. By assessing the potential health threats of cross-border transmission, public health officials can more effectively deploy preventive and response measures among ACSMs living and working near the US-Mexico border.