Journal of Tropical Medicine最新文献

Cholera, an intestinal infection caused by Vibrio cholerae, poses a severe threat to public health, particularly in developing countries. This narrative review discusses drivers for cholera outbreaks, challenges and viable alternatives, in Zimbabwe. A literature search was conducted using electronic databases notably ScienceDirect, Google Scholar and PubMed, as well as thesis and conference papers. Evidence indicates that the epidemiology, as well as risk factors, includes (1) extreme droughts; (2) political meddling in health issues and water supply; (3) natural disasters; (4) migration; (5) problems with water and sanitation; and (6) the endemic nature of the causative agent as well as its development of drug resistance. Reliable supply of clean water and proper sanitation and hygiene as the main key to prevention is emphasised. The use of antibiotics and vaccines for therapy, as well as the use of medicinal plants in traditional medicine, is discussed. Kirkia acuminata and Ziziphus mucronata root and stem bark infusions or decoctions were revealed to be the most common folklore treatments for cholera in rural communities. The potential of medicinal plants as anti-Vibrio cholerae remedies based on their positive antibacterial assays, and mechanism of action is also presented. Finally, the development of innovative anti-Vibrio cholerae therapeutics based on natural leads and compounds and adapted for use in resource-constrained cholera-prone areas is viewed as a potential option, to complement cholera prevention and treatment, particularly in resource-limited endemic areas.

Strongyloides stercoralis is a soil-transmitted helminth which is distributed predominately throughout tropical and subtropical regions and is considered a neglected tropical disease. Due to low larval output, traditional microscopic methods lack sensitivity, especially in areas of low endemicity. Serological assays present an opportunity to study the epidemiology of S. stercoralis in areas of low endemicity such as Jamaica. The current study evaluated the seroprevalence of S. stercoralis in a selected subpopulation in Jamaica. An analysis was conducted on 311 archived serum samples previously submitted for investigating viral infections during a fever epidemic between 2014 and 2015. Randomly selected, anonymized sera were tested for the presence of S. stercoralis IgG antibodies using the AccuDiag Strongyloides IgG ELISA Kit. Data including age, sex, clinical diagnosis, and the geographic location of sample submission were recorded to delineate trends in demographic variables. The seropositivity rate of S. stercoralis was 15.43%. The rate among females and males was 16.45% and 14.47%, respectively (χ ² = 0.2339, p=0.629). The highest rate was found in middle adulthood (31-50 years) (26.53%; 13/49). The seroprevalence of S. stercoralis was significantly highest in a rural Regional Health Authority (33.33%; 14/42) and least within an urban Health Authority (9.71%; 17/175). Exposure to S. stercoralis appears to be highest in the rural Regional Health Authorities with an island-wide exposure rate of 15.43%. The rapid ELISA testing method for the detection of IgG antibodies to S. stercoralis used in this study may be useful as part of a combined approach to elucidate the epidemiology of this soil-transmitted parasite in Jamaica.

Cryptosporidium infection is highly prevalent among immunocompromised patients with Acquired Immunodeficiency Syndrome, cancer, primary immunodeficiency, and organ transplant recipients. Comprehensive knowledge about Cryptosporidium infection provides the means for efficient diagnosis, treatment, and prevention. Therefore, with the objective of providing an in-depth analysis of Cryptosporidiosis in immunocompromised patients, this review presents a comprehensive understating of the prevalence, risk factors, pathophysiology of Cryptosporidium infection, clinical presentation in the immunocompromised, the immune response of the host, diagnostic methods performed in laboratory settings, possible treatments, and prevention methods, which can be used for further studies. Peer-reviewed, published, original articles on cryptosporidiosis in immunocompromised patients were searched using specific key-words on PubMed, ResearchGate, Google Scholar, and ScienceDirect databases. Articles which were accessible to the date of 18^th of August 2023, were included in this comprehensive review. We analyzed reports on Cryptosporidium in immunocompromised patients with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), cancer, primary immunodeficiency, and organ transplant recipients. 134 Articles describing epidemiology, related risk factors, clinical presentation, diagnosis, and possible treatments in the light of pathogenesis, pathophysiology, and virulence factors of Cryptosporidium and immunology of the host are summarized in this study. Effective treatments to be administered, importance, and ways of prevention were identified. Cryptosporidium infection was found to be highly prevalent among immunocompromised in Asia, Africa, Europe, and North America. The immunity of the host and the decrease in CD4⁺ T-cell count were found to the main factors which decide the susceptibility and the severity of infection. Drugs that activate host immunity and suppress Cryptosporidium growth, along with supportive therapy, is an effective treatment. But prevention is the most effective strategy for immunocompromised patients; thus, a better understanding about the disease would lead to effective prevention.

Background: Rapid diagnostic tests (RDTs) targeting pfhistidine-rich protein 2 (Pfhrp2) are widely used for diagnosis of Plasmodium falciparum infections in resource-limited malaria endemic countries. However, test results are affected by deletions of the Pfhrp2, Pfhrp3, and flanking genes and associated negative results from rapid diagnostic devices were previously reported. Therefore, the aim of this study was to reveal the existing genetic profile of Pfhrp2 and Pfhrp3 genes of P. falciparum-infected patients in northwestern Ethiopia. Methods: A total number of 302 blood samples were collected from children at Chilga (Aykel, Negade Bahir), and Sanja health centers in northwestern Ethiopia. Thirty-three (10.9%) samples tested positive for P. falciparum malaria. The Pfhrp2, Pfhrp3, and flanking genes (MAL7P1_228 and MAL7P1_230 for Pfhrp2, and MAL13P1_475 and MAL13P1_485 for Pfhrp3) were amplified using standard nested-PCR. Results: Pfhrp2 and both of its flanking genes were found to be present in 12 (36.4%) out of the 33 samples. Twenty-one (63.6%) samples tested negative for the Pfhrp2 gene and 19 samples (57.6%) tested positive for at least one of the flanking genes. Five (15.2%) samples gave positive results for the Pfhrp3 gene and both of its flanking genes, whereas 16 (48.5%) tested negative for all three. Conclusions: Our study provides widespread deletions in the Pfhrp2 and Pfhrp3 genes in Ethiopia, thereby confirming anecdotal reports of diagnostic failure with Pfhrp2-based RDTs in the region. The implications of our finding for the current diagnostic paradigm, which relies on the detection of P. falciparum by Pfhrp2-based RDTs in remote areas, may need rethinking.

Background: The incidence of Chikungunya in tropical Africa is still of major epidemiological significance. This study aims to determine the prevalence of chikungunya in East Africa through a systematic review and meta-analysis of published studies. Methods: We conducted a comprehensive search across six electronic databases-Web of Science, PubMed, ScienceDirect, Scopus, and Google Scholar-using specific keywords to address the worldwide impact of chikungunya following the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. A meta-analysis was performed on our eligible studies using the random effect model. Results: Our search returned 40 eligible articles involving 4122 Chikungunya cases in 13 East African nations. These studies, conducted between 2014 and 2024 across 13 East African nations, provided diverse data on chikungunya prevalence. The overall pooled prevalence of chikungunya in East Africa was 20.6% (95% CI: 18.8%-22.5% and I ² = 99.62%). Subgroup analyses revealed variations in prevalence across different countries, study designs, detection methods, and publication years. Notably, Rwanda and Djibouti exhibited high prevalence rates of 63.0% and 50.4%, respectively, while Kenya and Somalia reported a moderate prevalence of 12.2%. The detection methods also influenced prevalence rates, with RT-PCR studies indicating a higher prevalence (28.3%) compared to ELISA (19.3%). Conclusion: The study highlights the significant burden of chikungunya in East Africa, and the findings underscore the need for targeted public health interventions and improved surveillance to manage and control chikungunya outbreaks in the region.

Quercetin, a major representative of the flavonol subclass found abundantly in almost all edible vegetables and fruits, showed remarkable therapeutic properties and was beneficial in numerous degenerative diseases by preventing lipid peroxidation. Quercetin is beneficial in different diseases, such as atherosclerosis and chronic inflammation. This study aims to find out the anticancer activities of quercetin and to determine different mechanisms and pathways which are responsible for the anticancer effect. It also revealed the biopharmaceutical, toxicological characteristics, and clinical utilization of quercetin to evaluate its suitability for further investigations as a reliable anticancer drug. All of the relevant data concerning this compound with cancer was collected using different scientific search engines, including PubMed, Springer Link, Wiley Online, Web of Science, SciFinder, ScienceDirect, and Google Scholar. This review demonstrated that quercetin showed strong anticancer properties, including apoptosis, inhibition of cell proliferation, autophagy, cell cycle arrest, inhibition of angiogenesis, and inhibition of invasion and migration against various types of cancer. Findings also revealed that quercetin could significantly moderate and regulate different pathways, including PI3K/AKT-mTORC1 pathway, JAK/STAT signaling system, MAPK signaling pathway, MMP signaling pathway, NF-κB pathway, and p-Camk2/p-DRP1 pathway. However, this study found that quercetin showed poor oral bioavailability due to reduced absorption; this limitation is overcome by applying nanotechnology (nanoformulation of quercetin). Moreover, different investigations revealed that quercetin expressed no toxic effect in the investigated subjects. Based on the view of these findings, it is demonstrated that quercetin might be considered a reliable chemotherapeutic drug candidate in the treatment of different cancers. However, more clinical studies are suggested to establish the proper therapeutic efficacy, safety, and human dose.

Mosquitoes are the best-known disease vectors for most vector-borne diseases that significantly impact global health in terms of morbidity and mortality. In a geographical area, mosquito faunal diversity often alters with changing climatic factors and variable breeding habitats that differ across seasons. Using biodiversity indicators as tools, a study was conducted in rural, peri-urban, and urban areas of district Ganjam, Odisha state, to determine mosquito faunal diversity as an approach to forecast the possible risk of disease transmission in the three representative topographies. A two-year study was undertaken to assess the alpha diversity of mosquito species by the numerical strength of the species using various eco-diversity indices. Species richness and abundance of mosquito species are significantly higher in peri-urban areas compared to urban and rural areas. The species dominance of Culex quinquefasciatus was observed in all three topographies, while Aedes aegypti, Aedes albopictus, and Anopheles stephensi were in urban areas. Species richness may dilute the risk of disease in an area, but increased species dominance, mostly vector species, in a new habitat often allows pathogens to infect newer communities at risk, leading to the emergence of new diseases. The current study indicates the possible risk of lymphatic filariasis (LF) infection in all three topographies. On the other hand, the risk of malaria and dengue/chikungunya transmission is higher in urban areas. With routine entomological monitoring, including vector incrimination, the biodiversity indicators will be the best tool to forecast the risk of vector-borne diseases in an area; accordingly, judicious vector control strategies can be adopted.

Objectives: Due to Albendazole's relatively low efficacy and bioavailability, Echinococcosis has proven a challenge to manage successfully, with several studies investigating ways to improve the outcome, mainly showing mixed results. We, therefore, aimed to evaluate whether Sulfonated Graphene Oxide (S-GO), as nanocarriers, could improve the mentioned outcome.

Methods: Echinococcus protoscoleces were divided into four groups based on the agent they received, which comprised control, S-GO, Albendazole, and Albendazole-loaded S-GO (S-GO-Albendazole). Then, the Bax and Bcl-2 gene expression levels and the number of surviving protoscoleces in each group were determined.

Results: Bax gene expression increased by 121% in the 50 μg/ml concentration of the S-GO-Albendazole, while Bcl-2 gene expression decreased by 64%. Moreover, S-GO-Albendazole was approximately 18% more effective at neutralizing protoscoleces than Albendazole and 14% and 31% more effective at improving the expression of the mentioned genes, respectively (p < 0.05). In addition, the number of surviving protoscoleces after exposure to the mentioned concentration reduced by approximately 99%.

Conclusions: S-GO, despite not having significant lethality on protoscoleces, significantly increased the lethality of Albendazole and, therefore, is a suitable nanocarrier. However, we recommend conducting in vivo and clinical studies to more accurately determine this nanocomplex's potential and side effects.

Introduction: The aerial part of Ludwigia octovalvis has been used traditionally in some parts of Asia for the management of wounds owing to the presence of phytochemicals such as tannins, flavonoids, and triterpenoids among others. The incidence of wounds, their associated complications, and the cost of wound care are on the increase globally, therefore, the need to develop alternative wound care agents. The aim of this study was to scientifically investigate the wound healing potential of the ethanolic extract of L. octovalvis using the excision wound healing model in rats and also carry out an acute dermal toxicity investigation of the plant extract.

Method: A 70% ethanol extract of L. octovalvis was prepared for the wound healing activity using the excision wound healing model in Sprague-Dawley rats. Aqueous creams (1, 3, and 10%) were prepared and topically applied to the wounds once daily according to the groups of animals. The wounds were assessed for rates of wound closure on days 3, 5, 7, 9, and 11. Re-epithelialization periods were also determined. Sections of wound tissues obtained on day 13 were subjected to histological investigations. An acute dermal toxicity of the plant extract was investigated.

Results: L. octovalvis treatment (1, 3, and 10%) exhibited a mean percentage wound contraction range of 85.36 ± 7.22-94.14 ± 2.23 on day 11. The extract exhibited re-epithelialization periods of 17.3 ± 1.2, 19.8 ± 2.6, and 16.0 ± 1.7 days for the 1, 3, and 10% extract creams, respectively, whereas the cream-only and 1% silver sulfadiazine treatments resulted in a re-epithelialization period of greater than 28 days. Histopathological investigation revealed enhanced fibroblast infiltration and collagen deposition in the treatment groups. No adverse reaction was observed in the acute dermal toxicity study.

Conclusions: Extract of L. octovalvis exhibited wound healing by enhancing wound contraction, re-epithelialization, fibroblast infiltration, and collagen deposition at the wound site. The extract did not exhibit any toxic reaction in the acute dermal toxicity study.

Introduction: Coinfection of dengue virus and SARS-CoV-2 infections in dengue-endemic areas is a significant public health concern. Coinfections can result in severe illness. Hence, this study determines the incidence of dengue and COVID-19 coinfection for a better understanding of the clinical presentation, laboratory parameters, and outcomes including mortality.

Methods: The patients admitted to two tertiary hospitals with RT PCR-proven COVID-19 infection and dengue positive by NS1 rapid antigen or IgM dengue ELISA for two years between January 2020 and December 2022 were considered. Clinical data were retrieved from medical records including the laboratory findings and outcomes of these patients. The categorical data were analyzed in the form of frequency and proportion. The quantitative data were analyzed in the form of mean, median, and proportion.

Results: Out of 2301 confirmed dengue samples and 3718 confirmed COVID-19 samples, there were 14 cases of coinfection with the presence of COVID-19 and dengue infection at the same time. ICU admission of 14.2% and mean hospital stay of 7 days were noted. Mainly the symptoms reported were fever at 92.9%, myalgia at 35.7%, and headache, vomiting, and cough at 28.6%. The laboratory findings were elevated lactate dehydrogenase and C-reactive protein in 100% of patients, elevated ferritin in 92.9%, thrombocytopenia in 71.4%, elevated AST and ALT in 71.4%, and elevated D-dimer in 57.1% of patients. There was no effect on morbidity and mortality seen among coinfection.

Conclusion: COVID-19 and dengue share similar clinical features and laboratory findings. Diagnosis of one disease cannot rule out the presence of other infections. There might be chances of misdiagnosis or missed diagnosis. Hence, it is important to stress about early detection using specific methods and confirmation of disease with timely management, as it is a potentially new dimension for public health concern and management.