Journal of Tropical Medicine最新文献

Background: Although MMR vaccination can induce mumps infections, clustered cases right after the vaccination are rarely reported. On September 10, 2024, the Department of Disease Control, Thailand, received a report of a cluster of practical nursing students (PNSs) with jaw and ear swelling following an MMR (L-Zagreb strain) vaccination. An investigation was conducted to confirm the outbreak, identify sources and risk factors, and recommend preventive measures. Methods: Active case findings were conducted among PNS and hospital service recipients who received the suspected vaccine batches. Suspected cases of MMR-related mumps infection were defined as individuals experiencing either jaw swelling/pain, testicular swelling/pain, or groin pain 12-25 days postvaccination. Confirmed cases had positive RT-PCR for mumps. SH gene sequencing determined mumps phylogenetics, while nanopore sequencing of the NP gene assessed polymorphisms. Group and in-depth interviews with vaccine suppliers, pharmacists, nurses, and PNS evaluated the vaccine cold chain and setting. A retrospective cohort study among PNS used questionnaires on demographics and vaccination history to identify risk factors, analyzed via multivariable logistic regression. Qualitative data underwent content analysis. Results: Two batches of MMR vaccine were suspected and immediately suspended. Of the 108 vaccinated PNS, 12 met the case definition (eight suspected and four confirmed), yielding an attack rate of 11.1% (12.5% in males and 10.9% in females). Among 61 hospital vaccine recipients who received the same vaccine batches, 30 were contactable, and none met the case definition. All cases had ear/jaw pain, with 41.7% experiencing sore throats and 33.3% myalgia, though none were severe. Three confirmed cases had genetic material aligning with the L-Zagreb strain (Accession AY685920). No NP gene polymorphisms were detected in vaccines, though specimen buccal swabs had insufficient genetic material. Two factors may link to the adverse event: prior MMR vaccination (aOR = 12.90, 95% CI: 1.39, 172.00) and a delay of over 15 min from vial retrieval to administration (aOR = 26.90, 95% CI: 4.20, 247.00). Vaccine supply, distribution, and storage met standards, but vaccine campaign registration and waiting time processes require improvement. Conclusion: MMR-related mumps infections were confirmed during PNS mass vaccination campaign. Potential risk factors include a history of prior MMR vaccination and delay time from vial retrieval to vaccine administration. Improvements are needed in vaccination campaigns, particularly in the registration system and expediting vaccination process flow.

Soil-transmitted helminth (STH) infections are the most common parasitic infections worldwide, particularly in tropical regions. There are currently no reports on the prevalence of STH infections among children in Koh Yao District of Phang Nga Province, Thailand. Therefore, this study aims to assess the prevalence of STH infections and associated risk factors among primary schoolchildren. A school-based cross-sectional study was conducted among 243 schoolchildren aged 7 to 12 years from 12 rural primary schools across three subdistricts. Demographic data and associated risk factors were collected and analyzed. Stool samples were collected and examined for parasites using the formalin-ethyl acetate sedimentation concentration and the modified Kato-Katz methods. A multivariate logistic regression analysis was used to determine the strength of the relationship between risk variables and STH infections. Of the 243 participants (mean age: 8.99 ± 1.57 years), 12 (4.94%, 95% CI: 2.60%-8.50%) were infected with STH. The most common STH infection was hookworm (4.11%), followed by Trichuris trichiura (1.65%). More than 80% (n = 10, 83.33%) had a single intestinal parasite, while two (16.67%) were coinfected with two parasitic species. Infections were more prevalent among males (66.67%) compared to females (33.33%). Multiple regression analyses revealed that children above Grade 3 had a significantly higher prevalence of STH infections compared to those below Grade 3 (adjusted odds ratio [AOR] = 10.54; 95% CI: 1.24-89.14, p = 0.031). Open defecation was also statistically associated with STH infections (AOR = 22.66; 95% CI: 1.18-433.58, p = 0.038). This study highlights a low prevalence of STH infections in the study area, with hookworm being the most common. The potential risk factors identified were linked to educational level and open defecation practices. Improving sanitation and enhancing health education to raise public awareness about hygiene are essential strategies for controlling STH infections among primary schoolchildren in remote areas.

Background: Antimicrobial resistance (AMR) is a major global threat to public health and development. The emergence of drug-resistant pathogens compromises the effectiveness of current treatments and necessitates the discovery of new antimicrobial agents. Objective: This study aims to evaluate the antimicrobial potential of Toxocara canis adult and larval somatic and excretory-secretory (ES) antigens against common bacterial pathogens, including Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, and Salmonella enterica. Methods: Adult Toxocara canis worms were collected and dissected to obtain somatic antigenic proteins. Larval somatic and ES antigenic proteins were prepared from hatched eggs. The antimicrobial activity of these antigens was evaluated using susceptibility assays and minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) tests. High-performance liquid chromatography (HPLC) was used to investigate the possible bactericidal properties in comparison with standard tetracycline antibiotics. Results: The somatic antigenic proteins of adult and larval T. canis worms and larval ES antigens showed effective antimicrobial potential against Staphylococcus aureus, but not against the other 3 bacteria. HPLC analysis suggested that the bactericidal properties of these proteins may be close to that of tetracycline antibiotics because of the similar retention time. Conclusion: The preliminary study provides evidence of the antimicrobial properties of different stages of T. canis antigens, offering potential new solutions to combat AMR. Further research is needed to elucidate the mechanisms of action and assess the clinical applications of these antigenic proteins.

Background: Utilization of video capsule endoscopy (VCE) for the evaluation of small bowel disease is limited in Africa. The predominant causes of gastrointestinal disease in this region are infectious, but the prevalence of inflammatory bowel disease and malignancies is rising. We sought to evaluate the indications and outcomes of VCE in sub-Saharan Africa. Methods: We conducted a retrospective study at an outpatient gastroenterology center in Nairobi, Kenya. Data collected included demographics of the study population, procedure indication, prior investigations, findings, and complications of VCE. Descriptive statistics were used to analyze the results, and statistical analysis of association was performed using Fischer's exact test; a p value of less than 0.05 was considered significant. Results: A total of 72 patients underwent VCE from January 2017 to April 2022. The mean age was 59.1 years (range: 15-91); 61.7% were males. A total of 97.2% of the patients had a preceding upper and lower endoscopy. The indications were obscure gastrointestinal bleeding (GIB) in 51.4%, anemia (15.5%), abdominal pain (25.4%), altered bowel habits (23.9%), weight loss (9.9%), and suspected Crohn's disease (7.0%). The overall diagnostic yield was 77.1% and included angiodysplasia (14%), duodenitis (10.7%), mass/polyps (8.9%), suspected intestinal tuberculosis (7.1%), and helminths (2.8%). Angiodysplasia was the most common cause of GIB, accounting for 35.3% and 35.0% of occult and overt bleeding, respectively. Capsule retention occurred in 2 patients (2.8%). Conclusions: There are similarities in indications and preceding workup in our cohort compared to existing literature from Western and Asian countries. Infectious causes of GIB were unique to our study.

[This corrects the article DOI: 10.1155/2021/6273954.].

Diverse virulence genes encode for the Type III secretion system (T3SS) in bacteria. In Salmonella, these genes are located in the Salmonella pathogenicity Islands 1 and 2 (SPI-1 and SPI-2), and they facilitate bacterial invasion and replication within macrophages, contributing to the burden of nontyphoidal Salmonella infections. In this study, we investigated the prevalence of selected virulence-encoding genes in 30 laboratory stocks of Salmonella enterica serovar Enteritidis from Nigeria (16 isolates) and nonclinical sources comprising poultry and seafood from India (14 isolates). Analysis of PCR amplicons revealed that the genes sseB, sseD, sseF, sseT, and invH were conserved in all the isolates except for two isolates obtained from clams, which did not have the sseD and sseF genes. In addition, the sseC and sseG genes were absent from all the tested isolates. This study provides insights into the distribution of selected T3SS genes among Salmonella spp. isolated from clinical and raw animal food sources in Nigeria and India, respectively.

Epstein-Barr nuclear antigen 1 (EBNA1) is an attractive therapeutic target for identifying pharmaceutical drug molecules to fight Epstein-Barr virus (EBV) contagion because of its key function in viral reproduction. To find potent EBNA1 inhibitors, the Naturally Occurring Plant-based Anticancer Compound-Activity-Target (NPACT) database, including > 1500 compounds, was filtered utilizing computational approaches. The efficiency of the docking technique used to anticipate the inhibitor-EBNA1 binding pose was initially evaluated based on obtainable experimental data. Upon the computed docking scores, molecular dynamics simulations (MDSs) were executed for the most superior NPACT compounds bound to EBNA1, accompanied by binding affinity estimations utilizing the MM/GBSA approach. According to binding affinity computations over 200 ns MDS, bitucarpin A demonstrated stronger ΔG _binding than KWG, an EBNA1 reference inhibitor, with values of -39.1 and -32.4 kcal/mol, respectively. Post-MD analyses assured the steadiness of bitucarpin A inside the EBNA1 binding pocket over 200 ns MDS. Besides, pharmacokinetics, physicochemical, and toxicity features were predicted for bitucarpin A and demonstrated its promising oral bioavailability. Density functional theory calculations were executed, and their outcomes substantiated the results given by docking and MDS computations. According to these findings, bitucarpin A showed promising inhibitory activity as a potent EBNA1 inhibitor that may be a prospective anti-EBV drug candidate.

Background: Medicinal plants are used in Namibia for oral hygiene and to treat oral diseases. Validating the content and efficacy of medicinal chewsticks used in communities helps to provide proof of concept of medicinal plants used as a complementary/alternative medicine for oral diseases. Aim: This study presents the first report on quantified phytoconstituents, antimicrobial, time-kill kinetics, and biofilm inhibition properties of Diospyros lycioides organic and aqueous extracts against Enterococcus faecalis. Methodology: Dry plant materials were ground into powder and macerated in methanol and distilled water. Different phytoconstituents were quantified by Folin-Ciocalteu colorimetric method, ferric reducing antioxidant power assay, and DPPH free radical scavenging. An antibacterial assay was performed using the agar well diffusion method and a resazurin 96-well-based assay. Kill-time assay was done at various concentrations over 4 h. Biofilm inhibition was done using the crystal violet method. Results: Higher total flavonoid, total phenol contents, and free radical scavenging abilities were reported in methanol twig extracts. Inhibition zones of 28 ± 0.82 mm, with MICs of 15.6 ± 0.00 μg/mL, are reported against E. faecalis. The bactericidal endpoint of D. lycioides organic extracts for E. faecalis was reached after 4 h of incubation at 8 × MIC (124.8 μg/mL). These were comparable to the positive control, gentamicin. The organic extracts showed ≥ 50% biofilm inhibition against root canal-infecting E. faecalis at concentrations between 7.8 and 500 μg/mL, indicating strong biofilm inhibition. Conclusion: The study demonstrated that D. lycioides crude extracts have promising antibacterial properties and can eradicate E. faecalis biofilms in root canal treatments.

Background: Several studies have focused on the town of Kamituga, the epicentre of the current MPOX Clade Ib epidemic, in South Kivu Province, in the east of the Democratic Republic of Congo. However, the disease is widespread in several health zones in this province. Objectives: The aim of this study was to describe the clinical characteristics and vital prognosis of admissions for MPOX in the city of Bukavu (21,808 inhabitants/km²), in the province of South Kivu. Methodology: Between 1 July and 31 December 2024, MPOX patients were recruited as and when they were admitted to the treatment centre at the Bukavu university clinics. For each patient, clinical characteristics and outcome were sought. Results: Of the 343 patients hospitalized during this study period, 201 (58.6%) were men and 142 (41.4%) were women (p=0.001). The median age was 21.0 (11.0-27.7) years. Traders (42.3%) and field workers (24.7%) were more numerous. Contact with an MPOX case (61.2%) was the most frequent mode of contamination. The frequency was 70.2% for elevated white blood cells, 73.0% for elevated c-reactive protein, 37.9% for anemia, 43.1% for genital lesions, 7.0% for pregnancy and 2.6% for HIV. Finally, during the 2400 patient-day observation period, 3 patients subsequently died (0.8%). The incidence of death was 1.25/1000 patient days. Conclusion: The results of this study show that, in the city of Bukavu, MPOX is a disease of young people. Contact with a case of MPOX was the most important mode of contamination, and the professions at risk were trade and field work. Thus, the list of professions at risk of MPOX to be vaccinated must be established according to each region.