Journal of Tropical Medicine最新文献

Background: Conventional polymerase chain reaction (PCR) assays are well-established molecular techniques that can be integrated as standard diagnostic tools, especially in referral settings. This study aimed to assess the diagnostic potential of a multiplex PCR (mPCR) assay for the diagnosis of cutaneous leishmaniasis (CL), skin tuberculosis, and leprosy.

Method: A cross-sectional study was carried out involving 62 patients in the study group, comprising 45 with CL, 9 with leprosy, 4 with skin tuberculosis, and 4 with coinfections. Additionally, 112 positive control DNA samples were analyzed, including 37 of M. tuberculosis, 46 of M. leprae, and 29 of L. aethiopica. The study assessed sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and detection limits.

Results: Sensitivity and specificity of the mPCR on positive and negative control samples were 100% (95% CI: 96.8%-100%) and 100% (95% CI: 94.9%-100%), respectively. Its sensitivity and specificity among the study group were 75.8% (95% CI: 63.3%-85.8%) and 100% (95% CI: 94.9%-100.0%), respectively.

Conclusions: With further validation on more clinical suspects, mPCR has the potential to facilitate diagnosis in settings with coendemic CL, leprosy, and skin tuberculosis.

Background: Nonfilarial elephantiasis, also known as podoconiosis, is a completely preventable, neglected tropical disease characterized by prominent swelling of the lower extremities. The disease is common in sub-Saharan Africa. However, its epidemiology varies from region to region. Its comorbidity with other diseases is also rarely studied in Ethiopia. A better understanding of podoconiosis and its comorbidity with tungiasis is crucial for the utmost consideration of the management and prevention strategies.

Objective: The study aimed to assess the magnitude and associated factors of podoconiosis and its comorbidity with tungiasis among residents of southwest Ethiopia.

Methods: A community-based cross-sectional study was conducted in selected districts of southwest Ethiopia from February to May 2023. After appropriate data collection and processing, the descriptive statistics were computed to determine the magnitude of podoconiosis and its comorbidity with tungiasis. A bivariate and multivariate logistic regression analysis was computed to identify the factors associated with podoconiosis in the frame of Hosmer-Lemeshow's goodness of fit.

Result: A total of 554 study participants were enrolled in the study. Podoconiosis was identified among 34 study participants, with a magnitude of 6.14% (95% CI: 4.21, 8.4%). Of the total podoconiosis-affected study participants, about 11.8% (n = 4) were simultaneously infected with tungiasis. The disease was found to be associated with occupation, time not wearing shoes, usage of soap for leg/foot washing, and family history of leg swelling in the study participants.

Conclusion: This study indicates a significant prevalence of podoconiosis and a notable comorbidity with tungiasis. The findings of this study highlight the need for targeted interventions on improved footwear practices and hygiene education in the study area. Moreover, potential genetic screening of the population in podoconiosis endemic areas can contribute to the early prevention of the disease, thus reducing its burden and alleviating the torment of the population.

Malaria remains a major global public health concern, particularly in tropical regions. The increasing resistance to the current antimalarial drugs highlights the urgent need for new and effective therapies. Medicinal plants offer a promising source of novel and affordable antimalarial compounds for drug development. This study aimed to evaluate the antimalarial potential and acute oral toxicity of ethanolic leaf extract of Mussaenda erythrophylla Schum. & Thonn. (M. erythrophylla or Dona Trining) and Mussaenda philippica Dona Luz x M. flava (M. philippica or Dona Marmalade). Male Institute of Cancer Research (ICR) mice were treated with crude extracts at doses of 200, 400, and 600 mg/kg body weight, and the antimalarial activity was assessed using a 4-day suppressive test against Plasmodium berghei ANKA strain. The ethanolic leaf extract of M. erythrophylla exhibited a parasite suppression of 12.31%, 39.59%, and 59.76% at 200, 400, and 600 mg/kg, respectively. Similarly, M. philippica leaf extract suppressed parasitemia by 36.18%, 36.40%, and 71.02% at the corresponding doses. All extract concentrations, except for the 200 mg/kg dose of M. erythrophylla, exhibited higher effects compared to the negative controls (p < 0.05). At a dose of 2000 mg/kg, acute oral toxicity testing revealed no changes in ALT, ALP, BUN, or creatinine levels compared to controls, although AST levels were elevated. This increase was considered a possible mild adaptive response rather than a sign of overt toxicity. No alterations were observed in the physical activity or behavior of the mice, including piloerection, lacrimation, feeding activity, abnormal secretions, sleep patterns, or unusual excitement. Additionally, neither crude extract induced histological alterations in liver or kidney tissues. In conclusion, ethanolic leaf extracts of M. erythrophylla and M. philippica demonstrated promising antimalarial activity and were deemed safe at the tested doses, demonstrating safety up to 2000 mg/kg with only mild AST elevation and no observable histopathological damage. Extending the previous in vitro results of potent antimalarial activity and low cytotoxicity, our in vivo findings strongly support the efficacy and safety of these extracts. Further research is recommended to isolate and identify the active compounds responsible for the observed effects.

Introduction: Arboviral diseases transmitted by the Aedes aegypti mosquito cause high morbidity and mortality worldwide.

Objective: To evaluate the repellent and insecticidal efficacy of water-soluble formulations of essential oils impregnated into mosquito nets against the adult stage of A. aegypti.

Methodology: A randomized laboratory bioassay was conducted using a controlled factorial design to evaluate four essential oil formulations (Eucalyptus globulus, Cymbopogon citratus, Origanum vulgare, and Mentha piperita) at concentrations of 10, 100, and 250 mg/mL. Each experimental group consisted of 60 laboratory-reared adult female A. aegypti specimens. The repellent effect, protection time, and insecticidal effect were evaluated by exposing the insects to a sedated animal bait (Rattus norvegicus albinus) covered with a mosquito net impregnated with the formulations of essential oils and DEET, as a positive control.

Results: The highest efficacy was seen in C. citratus, E. globulus, and O. vulgare at 250 mg/mL, with 93.3%-100.0% repellent effect and 180 min of protection time, similar to that obtained by 100 mg/mL DEET. The highest insecticidal effect was observed in C. citratus (26.7%) at a concentration of 250 mg/mL, similar to that observed in 100 mg/mL DEET. The repellent effect and protection time varied for each concentration tested, except for the insecticide, in which concentrations of 10 and 100 mg/mL had a similar effect (0%-6%).

Conclusions: The repellency of water-soluble formulations of essential oils of C. citratus, E. globulus, and O. vulgare at 250 mg/mL, compared to 100 mg/mL DEET, represents a possible and complementary alternative for mosquito control.

As the second most deadly infectious disease worldwide after COVID-19, tuberculosis (TB) remains a pressing global health issue, further aggravated by multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB) strains. There is an urgent need to identify new anti-TB treatments and novel therapeutics to confront drug resistance. The decaprenylphosphoryl-D-ribose oxidase (DprE1) is an essential protein for the biosynthesis of the mycobacterial cell wall, and its inhibition features a promising antitubercular strategy. NPAtlas was utilized as a reference database, comprising natural products with confirmed biological effects. The aim of the current study is to identify and prioritize promising nitro-containing natural products from the NPAtlas as potential covalent DprE1 inhibitors using advanced in silico approaches. Herein, the docking scores of 133 nitro-containing NPAtlas compounds were assessed using a covalent docking technique. Thereafter, NPAtlas compounds with docking scores lower than PBTZ169 (calc. -7.8 kcal·mol^-1) were subjected to molecular dynamics simulation (MDS), accompanied by binding energy estimations utilizing the MM-GBSA approach. Based on MM-GBSA//250 ns MDS, NPA011203, NPA013234, NPA016048, NPA012944, NPA001712, and NPA002823 demonstrated higher binding affinities against DprE1 with ΔG _binding values of -75.6, -62.7, -61.6, -57.6, -54.8, and -50.7 kcal·mol^-1, respectively, than PBTZ169 (calc. -49.4 kcal·mol^-1). The identified NPAtlas compounds also demonstrated structural and energetic stability within the DprE1 active site throughout 250 ns MDS. Physicochemical and ADMET predictions of the identified NPAtlas compounds indicated a suitable molecular size, favorable absorption, and negligible toxicity, suggesting their potential oral bioavailability. These in silico outcomes provide preliminary insights into the identified NPAtlas compounds as potential DprE1 inhibitors and can guide subsequent in vitro/in vivo experiments.

Objective: The aim of this study was to investigate the predictive effect of laboratory results and blood gas values on the selection of respiratory support models in infants diagnosed with transient tachypnea of the newborn (TTN).

Method: The study was designed as a single-center, retrospective study. Infants born with gestational age ≥ 35 weeks diagnosed with TTN during a 2-year period were included. Demographic characteristics, laboratory parameters, respiratory support models, and length of hospital stay were recorded. The relationship between the obtained parameters and the percentage and duration of oxygen requirement, nasal continuous positive airway pressure (nCPAP), nasal synchronized intermittent mandatory ventilation (nSIMV), intubation, and hospitalization duration was evaluated.

Results: The study was completed with 327 infants. A correlation was found between pH and pCO2 values in the first blood gas analysis and the duration of oxygen administration (p : 0.019 and p : 0.001), and between serum calcium levels and peak sodium levels and the duration of nSIMV (p : 0.04 and p : 0.023). Low serum calcium, phosphorus, and initial sodium levels were identified in infants requiring invasive ventilation (p : 0.001, p : 0.006, and p : 0.012, respectively). In the ROC analysis used to predict intubation, the cutoff value for calcium was determined as < 8.11 mg/dL (AUC 0.771, [95% CI: 0.669-0.872], p : <0.001). For predicting the need for nCPAP, the cutoff value for pH in the first blood gas analysis was < 7.32 (AUC 0.705, [95% CI: 0.586-0.823], p : 0.003), and for predicting the need for nSIMV, the cutoff value for pH was < 7.28 (AUC 0.599, [95% CI: 0.535-0.663], p : 0.003).

Conclusions: It was determined that the initial blood gas pH and pCO2 values, as well as serum sodium, calcium, and phosphorus levels, could be used to predict the treatment model in infants diagnosed with TTN. Low calcium, phosphorus, and sodium levels were found in TTN-diagnosed infants requiring invasive mechanical ventilation.

Background: Malaria remains a persistent public health concern in Iran, particularly in southeastern regions bordering Afghanistan and Pakistan. Despite substantial progress over recent decades, challenges such as cross-border transmission, insecticide resistance, and health system disruptions continue to threaten elimination goals.

Methods: This narrative review synthesized evidence from the World Health Organization (WHO) World Malaria Reports, national surveillance summaries, and peer-reviewed publications indexed in PubMed and Scopus from 2000 to 2025. Emphasis was placed on case trends, intervention coverage, and cross-border dynamics.

Results: Iran reduced indigenous malaria cases dramatically from thousands in the early 2000s to fewer than 300 annually by the mid-2010s and subsequently recorded multiple consecutive years with zero indigenous transmission, according to the WHO surveillance reports. Key achievements included integrated vector management, community engagement, and strengthened cross-border initiatives. However, interruptions during the COVID-19 pandemic and a resurgence of malaria in 2022, largely associated with imported infections, operational disruptions, and emerging vector threats, highlighted vulnerabilities in elimination-phase systems. Additional challenges such as insecticide resistance and the spread of Anopheles stephensi further complicate the elimination trajectory.

Conclusion: Iran's experience illustrates the need for adaptive, multisectoral approaches to malaria control in complex socioecological settings. While elimination remains within reach, achieving the WHO certification will require transparent surveillance metrics, reinforce cross-border collaboration, and sustain political and financial commitment.

Background: Polyparasitism is commonly associated with Plasmodium species, Schistosoma species and soil-transmitted helminths. Anaemia results from a variety of causes, including parasitic infections. Women of reproductive age (WRA) and children below the age of five are disproportionately affected by polyparasitic infections, putting them at risk of anaemia. The current study was conducted to evaluate the association of polyparasitic infections with anaemia among WRA in Kilifi.

Materials and methods: A cross-sectional study was conducted among 478 WRA in Rabai and Magarini subcounties in Kilifi County. Blood samples were collected and analysed for Plasmodium falciparum, determination of haemoglobin (HB), and classification of anaemia, while urine and stool samples were tested for Schistosoma haematobium and soil-transmitted helminths, respectively. Data were analysed using R software, and the overall magnitude of parasitic coinfections, anaemia and their associated factors was determined by chi-square and t-test. The differences were considered statistically significant if p-value was ≤ 0.05. The means of HB were determined to evaluate the synergistic effect of different single parasites in polyparasitism on HB at a 95% confidence interval.

Results: The overall prevalence of parasitic infections was 26.9%. Polyparasitism had a prevalence of 1.8% due to concurrent infection of P. falciparum and S. haematobium, S. haematobium and hookworm, S. haematobium, hookworm and Ascaris lumbricoides, whose prevalence was 0.8% (p < 0.001). 0.8% (p < 0.001) and 0.2% (p < 0.001) respectively. The prevalence of anaemia was 16.5%, while the prevalence of normocytic and microcytic anaemia was 63% and 37%, respectively. There was no synergy between different parasites in polyparasitism and HB.

Conclusion: The study findings indicated that the prevalence of polyparasitism was low. Polyparasitic infections involving S. haematobium and P. falciparum were most common in the region. Anaemia was common among P. falciparum and Trichuris trichiura-infected participants, while normocytic and microcytic anaemia were common in both infected and noninfected women.

Background: Ebola virus disease (EVD) remains a significant public health threat in sub-Saharan Africa. Jinja District in Uganda has experienced two EVD outbreaks in the recent past, first in November 2022 and again in February 2025, positioning it among the country's EVD hotspots during Uganda's eight recorded outbreaks. This study assessed the readiness of healthcare facilities by identifying existing gaps and strengths and providing evidence to inform targeted interventions to strengthen emergency preparedness and response.

Methods: A cross-sectional study was done using the WHO EVD readiness checklist. Data were collected through observations, interviews, and document reviews, and indicators were scored accordingly. Thematic analysis was used to summarize strengths and weaknesses and to categorize EVD readiness response based on indicator scores.

Results: A total of 36 healthcare facilities were assessed in Jinja District, yielding an overall district EVD readiness score of 82%. Among the key indicators, coordination scored highest at 93%, while community engagement scored lowest at 77%. Based on facility-level assessments, 20 facilities (55.6%) demonstrated high EVD readiness, 7 (19.4%) had medium readiness, and 9 (25%) showed low readiness. At the facility level, average scores across indicators were coordination (97.2%), surveillance (86.1%), case management and infection prevention and control (85.7%), community engagement (71.4%), logistics and supply chain (65.7%), and laboratory systems (60.0%).

Conclusion: The assessment shows encouraging levels of Ebola readiness in a majority of Jinja District facilities, especially in coordination and surveillance. However, noticeable gaps remain in community engagement, IPC implementation, logistics, and laboratory systems, especially among low- and medium-performing facilities. These findings highlight the need for targeted support, regular assessments, supply chain strengthening, and continuous capacity-building to ensure all facilities can effectively respond to future EVD threats.

Background: Synthetic insecticides face challenges, such as resistance, environmental damage, and harm to nontarget species, highlighting the need for alternative methods. Medicinal plants, along with their bioactive compounds, offer a promising solution.

Objective: This study investigated the efficacy of methanol extracts derived from traditionally used Ethiopian medicinal plants against Anopheles arabiensis and Aedes aegypti.

Methods and materials: Methanol extracts (80%) of the crude plant extracts were tested on the larvae and eggs of both mosquito species at concentrations ranging from 250 to 2000 ppm. Larval mortality was recorded after 24 h of exposure, while egg hatchability was assessed after 72 h.

Results: Millettia ferruginea exhibited the highest larvicidal activity against Anopheles arabiensis (LC₅₀ = 461.7 ppm, LC₉₀ = 1746.8 ppm), achieving 90% inhibition of egg hatching at 2000 ppm. Momordica foetida resulted in 85% mortality in second-instar larvae and 80% mortality in early fourth-instar larvae of Anopheles arabiensis at 2000 ppm. Securidaca longepedunculata demonstrated 87% larval mortality and 92% egg hatching inhibition in Aedes aegypti at 2000 ppm. ANOVA result shows that mortality rates varied significantly across concentrations (p < 0.05).

Conclusion: Millettia ferruginea, Momordica foetida, and Securidaca longepedunculata are promising botanical insecticides. Future studies should focus on isolating active compounds to ensure environmental safety and effectiveness. These findings highlight the potential of indigenous plants for insect management and underscore the importance of traditional knowledge in the development of novel insecticides.