Tropical Diseases, Travel Medicine and Vaccines最新文献

Lyme disease, caused by Borrelia burgdorferi and transmitted by Ixodes ticks, is rare in South America and is often misdiagnosed in returning travelers. We report the case of a 19-year-old Peruvian male who presented with pruritic erythematous maculopapular lesions and abdominal pain after travel to Maryland, United State of America. His atypical cutaneous findings, including a crusted lesion with ill-defined borders and a maculopapular rash, were initially misinterpreted as bacterial cellulitis, resulting in multiple unsuccessful courses of antibiotics. Further evaluation, guided by his travel history, led to the diagnosis of Lyme disease through serological testing and histopathology. Treatment with doxycycline achieved complete resolution. This case illustrates the diagnostic challenges posed by atypical presentations of Lyme disease in nonendemic regions. Greater awareness among clinicians in South America is essential to recognize imported cases, facilitate early diagnosis, and prevent complications associated with delayed treatment.

Background: Malaria, is an endemic disease which causes significant mortality worldwide, particularly in Africa, including Cameroon. This study aimed to characterize the Pfdhps resistance gene of Plasmodium falciparum in three hospitals in Mbouda Cameroon.

Method: Two hundred and ninety-six samples were collected from consenting patients for rapid diagnostic tests (RDT) and thick blood smear (TBS) to determine parasite intensity. Positive samples were spotted on Whatman paper for molecular analysis. Plasmodial DNA was extracted using the Chelex-100 method, and amplification was performed via nested PCR. The A437G and A581G mutations were identified using restriction fragment length polymorphism (RFLP) with AvaII and BstUI enzymes, followed by 1.3% agarose gel electrophoresis. Data were analyzed using SPSS 21 software.

Results: The prevalence of Plasmodium falciparum was 25.34%. The Pfdhps resistance gene prevalence was 74.66%, with A437G 56% and A581G 64% mutations. the age group [6-35] are the majority carriers of the gene and females (77.8%) have a higher prevalence of the gene than males (71.8%). Mutant alleles showed higher frequencies (57.14% for A437G and 91.66% for A581G) compared to wild-type alleles (42.85% for A437G and 8.33% for A581G). The mutant alleles of the two mutations are more predominant in the age group [6-35] and in females for A437G and in males for A581G.

Conclusion: The Pfdhps resistance gene was prevalent in Mbouda, with high rates of A437G and A581G mutations. These findings highlight the need for enhanced epidemiological surveillance of antimalarial resistance, particularly in Mbouda.

Background: Malaria remains a significant global health burden, necessitating the development of effective vaccines. Traditional vaccine development is challenged by the complexity of the Plasmodium parasite and lengthy empirical processes. Machine learning (ML) offers a promising avenue to accelerate and enhance vaccine research.

Aim: This review synthesizes recent advances in the application of ML to malaria vaccine research, focusing on immunological signature identification, antigen discovery, and predictive modeling of vaccine efficacy, to highlight its transformative potential.

Methods: A targeted literature search was conducted for peer-reviewed articles, reviews, and systematic analyses published between 2017 and 2025. Studies directly addressing ML or AI in malaria vaccine development were included. Data extraction covered ML methodologies, data types, applications, validation strategies, challenges, and limitations. Thematic analysis categorized findings, and a quality assessment ensured methodological rigor.

Results: Thematic analysis identified five key areas: (1) antigen discovery and prioritization using supervised and semi-supervised learning; (2) immune signature identification and efficacy prediction via diverse ML algorithms; (3) computational tool and framework development for data integration; (4) broad reviews of AI/ML applications; and (5) epidemiological modeling for policy support. Most studies were conducted in Europe and North America, often with collaborations in Africa.

Conclusion: ML is transforming malaria vaccine research by accelerating antigen discovery, enabling precise immune profiling, and predicting vaccine efficacy. Addressing data quality, model interpretability, and validation challenges is crucial for realizing the full potential of ML in developing next-generation malaria vaccines.

Background: Dermatologic conditions are among the most frequent health problems in international travelers, following gastrointestinal and febrile illnesses. Myiasis, defined as infestation of human tissue by dipterous fly larvae, represents a noteworthy dermatologic diagnosis, particularly in travelers returning from tropical regions. Furuncular myiasis is the most recognizable form, presenting with painful nodules containing larvae, and is commonly caused by Dermatobia hominis in Central and South America. Increasing international travel is expected to raise the incidence of such conditions in non-endemic regions.

Case report and discussions: We report the case of a 77-year-old Romanian male, with co-morbidities, who developed cutaneous furuncular myiasis following a 12-day trip to Brazil and Argentina. The patient presented with painful nodular skin lesions on the upper limb approximately one month after returning. Initial treatments with anti-inflammatory agents and antibiotics were ineffective. Subsequent surgical drainage revealed the presence of larvae, confirming the diagnosis. Complete healing occurred within 2-3 weeks. Based on clinical presentation and travel history, Dermatobia hominis was considered the most probable etiologic agent, although molecular confirmation was unavailable. Discussion highlights the epidemiology and classification of myiasis-producing flies, emphasizing the geographic distribution of Dermatobia hominis and Cochliomyia hominivorax. Furuncular myiasis is often misdiagnosed as cellulitis or abscess due to nonspecific symptoms. Key diagnostic clues include persistent nodules with central punctum, serous discharge, and recent travel to endemic areas. Ultrasound can aid in identifying larvae, while laboratory confirmation enhances epidemiological surveillance. Management typically involves mechanical or surgical larval extraction, wound care, and monitoring for secondary infection. Preventive measures include insect repellents, protective clothing, and use of insecticide-treated nets. This case underscores the need for heightened clinical awareness in non-endemic countries, where travel-related parasitic infections are increasingly encountered. Pre-travel medical consultations are crucial for providing vaccinations, preventive advice, and education on insect protection. While our patient experienced a favorable outcome, delayed diagnosis and lack of preventive measures may increase morbidity.

Conclusion: With the rising popularity of travel to tropical areas, clinicians should consider cutaneous myiasis in travelers with persistent nodular skin lesions. Prompt recognition and extraction of larvae remain the cornerstone of effective treatment.