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Trop. Med. Infect. Dis., Volume 9, Issue 7 (July 2024) – 19 articles

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8 pages, 184 KiB  
Article
Optimizing Trichiasis Case Finding to Attain the Elimination of Trachoma as a Public Health Problem
by Joy Shu’aibu, Grace Ajege, Caleb Mpyet, Michael Dejene, Sunday Isiyaku, Abubakar Tafida, Michaela Kelly, Innocent Emereuwa and Paul Courtright
Trop. Med. Infect. Dis. 2024, 9(7), 157; https://doi.org/10.3390/tropicalmed9070157 - 11 Jul 2024
Viewed by 124
Abstract
Background: As national trachoma programmes increase efforts to reduce the burden of trachomatous trichiasis (TT), TT case finding and referral are critical public health programme components. Our research aimed to explore the most effective and efficient approaches to finding, referring, and managing TT [...] Read more.
Background: As national trachoma programmes increase efforts to reduce the burden of trachomatous trichiasis (TT), TT case finding and referral are critical public health programme components. Our research aimed to explore the most effective and efficient approaches to finding, referring, and managing TT cases. Methods: This was a prospective descriptive study, utilizing both routine programme data and primary data collection. This study compared four different approaches to finding TT cases across three different local government areas (LGAs) in Kano State, Nigeria. Each of the study LGAs was divided into four sub-units to accommodate the four different approaches. Results: The number of outreach attendees was 4795 across the four case finding approaches, and this varied hugely, with the smallest number and proportion (403, 0.26%) in settings only employing house-to-house case finding and the largest number and proportion (1901, 0.99%) when town criers were used. That said, the proportion of TT cases among people presenting at outreach was highest (32.5%) when house-to-house case finding was used and lowest (10.3%) when town criers were used. More female TT patients were found (53–70%) and had surgery (79–85%) compared to male cases, across all approaches. The average project expenditure for finding one TT case was similar for approaches that included house-to-house case finding (USD 5.4–6.3), while it was 3.5 times higher (USD 21.5 per TT case found) when town criers were used. Discussion: This study found that the house-to-house TT case finding approaches were the most efficient method with the highest yield of TT cases. Including other eye condition and/or vision testing yielded similar results but required more personnel and cost. Full article
(This article belongs to the Special Issue Trachoma and Its Management)
13 pages, 1994 KiB  
Article
Evaluation of Mass Drug Administration Coverage for Lymphatic Filariasis in the Lukonga Health Zone in 2022
by Patrick N. Ntumba and Pierre Z. Akilimali
Trop. Med. Infect. Dis. 2024, 9(7), 156; https://doi.org/10.3390/tropicalmed9070156 - 11 Jul 2024
Viewed by 142
Abstract
(1) Background and rationale: To validate the reported therapeutic coverage, a lymphatic filariasis post-mass drug administration (MDA) campaign survey was conducted in the Lukonga health zone from 10 June to 15 July 2023. (2) Materials and methods: This was a descriptive, cross-sectional study [...] Read more.
(1) Background and rationale: To validate the reported therapeutic coverage, a lymphatic filariasis post-mass drug administration (MDA) campaign survey was conducted in the Lukonga health zone from 10 June to 15 July 2023. (2) Materials and methods: This was a descriptive, cross-sectional study conducted at the community level in 30 villages in the Lukonga health zone from 10 June to 15 July 2023. The study population included all individuals from the visited communities. The study variables included age, sex, drug use (ivermectin + albendazole), adverse events, and adherence to MDA guidelines for supervised drug use. Questionnaires were administered on Android phones using the SurveyCTO platform. Stata version 17 was used for data analysis. (3) Results: Of the 1092 respondents, 54.8% were female and one-third were between the ages of 5 and 14. Two-thirds of the households surveyed, or 64%, had more than six people living in them, and 1031 individuals, or 94%, reported being present during the community mass drug distribution. Notably, 678 individuals, or 66%, reported taking the drugs offered, and 66.4% of those who took the drugs reported doing so in the presence of drug distributors. Thus, the survey coverage was 65.7% [95% CI: 62.9–68.7]. The results of this study show that the survey coverage was above the 65% threshold recommended by the WHO but below the 82.3% reported by the Lukonga health zone. The main reason for non-compliance was a fear of ivermectin-related side effects (47%). Supervised or directly observed treatment was not adhered to (66.4%). (4) Discussion and conclusions: Key challenges to further increase treatment coverage include assessing data quality, building capacity, motivating drug distributors, improving data reporting tools, proper recording by drug distributors, and accurate reporting on non-residents who take the drugs during the MDA. In addition, harmonization of the numerator for calculating drug coverage in the health zone is critical. It is imperative to provide the public with explicit information regarding the objective of drug distribution and the probable adverse effects. Full article
(This article belongs to the Section Neglected and Emerging Tropical Diseases)
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8 pages, 183 KiB  
Opinion
Persons Living with HIV as a Vulnerable Group: An Argument to Ensure Treatment, Care, and Support
by Michelle Brotherton
Trop. Med. Infect. Dis. 2024, 9(7), 155; https://doi.org/10.3390/tropicalmed9070155 - 11 Jul 2024
Viewed by 111
Abstract
Generally, human rights documents are to be applied universally. However, certain groups are identified for special treatment due to vulnerabilities faced; these are often referred to as vulnerable groups or populations. While human rights literature and public health literature make a case for [...] Read more.
Generally, human rights documents are to be applied universally. However, certain groups are identified for special treatment due to vulnerabilities faced; these are often referred to as vulnerable groups or populations. While human rights literature and public health literature make a case for particular sensitivity regarding vulnerable populations living with HIV, there is perhaps a case to be made for people living with HIV to be recognised as a vulnerable group in and of itself. It is often other vulnerabilities, such as poverty, disability, or discrimination, that render persons living with HIV legally vulnerable. But what happens if these other vulnerabilities are not present? Persons living with HIV could benefit from being recognised as a vulnerable group, in that it could prioritise their health rights and promote their access to healthcare and services. This article considers how identifying persons living with HIV as a vulnerable group could impact their treatment, care, and support. By looking at examples of countries where people living with HIV have been identified as vulnerable, and at how vulnerable groups are defined, an argument is made that it could be beneficial to persons living with HIV to be identified as a vulnerable group in terms of accessing treatment, care, and support. Full article
13 pages, 708 KiB  
Article
Investigating the Determinants of Mortality before CD4 Count Recovery in a Cohort of Patients Initiated on Antiretroviral Therapy in South Africa Using a Fine and Gray Competing Risks Model
by Chiedza Elvina Mashiri, Jesca Mercy Batidzirai, Retius Chifurira and Knowledge Chinhamu
Trop. Med. Infect. Dis. 2024, 9(7), 154; https://doi.org/10.3390/tropicalmed9070154 - 10 Jul 2024
Viewed by 257
Abstract
CD4 count recovery is the main goal for an HIV patient who initiated ART. Early ART initiation in HIV patients can help restore immune function more effectively, even when they have reached an advanced stage. Some patients may respond positively to ART and [...] Read more.
CD4 count recovery is the main goal for an HIV patient who initiated ART. Early ART initiation in HIV patients can help restore immune function more effectively, even when they have reached an advanced stage. Some patients may respond positively to ART and attain CD4 count recovery. Meanwhile, other patients failing to recover their CD4 count due to non-adherence, treatment resistance and virological failure might lead to HIV-related complications and death. The purpose of this study was to find the determinants of death in patients who failed to recover their CD4 count after initiating antiretroviral therapy. The data used in this study was obtained from KwaZulu-Natal, South Africa, where 2528 HIV-infected patients with a baseline CD4 count of <200 cells/mm3 were initiated on ART. We used a Fine–Gray sub-distribution hazard and cumulative incidence function to estimate potential confounding factors of death, where CD4 count recovery was a competing event for failure due to death. Patients who had no tuberculosis were 1.33 times at risk of dying before attaining CD4 count recovery [aSHR 1.33; 95% CI (0.96–1.85)] compared to those who had tuberculosis. Rural patients had a higher risk of not recovering and leading to death [aSHR 1.97; 95% CI (1.57–2.47)] than those from urban areas. The patient’s tuberculosis status, viral load, regimen, baseline CD4 count, and location were significant contributors to death before CD4 count recovery. Intervention programs targeting HIV testing in rural areas for early ART initiation and promoting treatment adherence are recommended. Full article
(This article belongs to the Special Issue Infectious Disease Prevention and Control: A One Health Approach)
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11 pages, 4667 KiB  
Article
Epidemiological Characteristics and Spatiotemporal Patterns of Visceral Leishmaniasis in Xinjiang, China, during 2004–2021
by Jiangshan Zhao, Yue Zhang, Haiting Zhang, Shuo Wang, Haibo He, Guangzhong Shi, Wumaier Maimaitijiang, Yanyan Hou, Ling Zhang, Jianhai Yin, Yi Wang and Jianping Cao
Trop. Med. Infect. Dis. 2024, 9(7), 153; https://doi.org/10.3390/tropicalmed9070153 - 9 Jul 2024
Viewed by 328
Abstract
The spread of visceral leishmaniasis (VL), a serious global zoonotic parasitic disease, is mostly under control; however, several cases have been reported in recent decades in Xinjiang, China. This study aimed to analyze the epidemiological status and spatiotemporal clustering characteristics of VL in [...] Read more.
The spread of visceral leishmaniasis (VL), a serious global zoonotic parasitic disease, is mostly under control; however, several cases have been reported in recent decades in Xinjiang, China. This study aimed to analyze the epidemiological status and spatiotemporal clustering characteristics of VL in Xinjiang, China, between 2004 and 2021 to provide a basis for the development and implementation of surveillance and response measures. Data on VL incidence during 2004–2021 were collected from the National Diseases Reporting Information System of China. Global spatial autocorrelation analysis, identification of local indicators of spatial association, and spatial–temporal clustering analysis were conducted to identify the distribution and high-risk areas. A total of 2034 VL cases were reported, with a mean annual incidence of 0.50 per 100,000. There was a general decreasing trend in the incidence of VL during our study period. The majority of the cases were reported from October to February of the following year, and fewer cases were reported from April to July. Spatial autocorrelation analysis revealed that the incidence of VL was spatially clustered within a few counties. Significant differences were observed during the study period (Moran’s I = 0.74, Z = 4.900, p < 0.05). The male-to-female ratio was 1.37:1, and most patients were in the age group 0–3 years. Cases were primarily distributed in seven regions and two autonomous prefectures, and Kashgar reported the highest number of cases (1688, 82.98%). Spatial analysis revealed that the aggregation of VL was predominantly observed in southwest Xinjiang. This was in alignment with the high-risk areas identified by spatiotemporal clustering analysis. The H-H clustering region was primarily observed in Gashi, Atushi, Shufu, Injisha, Kashgar, Yepuhu, and Bachu. These findings indicate that integrated control measures must be taken in different endemic areas to strengthen the VL control program in Xinjiang, China. Full article
(This article belongs to the Section Vector-Borne Diseases)
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10 pages, 452 KiB  
Article
16S rDNA Sequencing for Bacterial Identification in Preterm Infants with Suspected Early-Onset Neonatal Sepsis
by Sergio Agudelo-Pérez, A. Melissa Moreno, Juliana Martínez-Garro, Jorge Salazar, Ruth Lopez, Mateo Perdigón and Ronald Peláez
Trop. Med. Infect. Dis. 2024, 9(7), 152; https://doi.org/10.3390/tropicalmed9070152 - 6 Jul 2024
Viewed by 248
Abstract
Background: The high prevalence of suspected early-onset neonatal sepsis among preterm infants leads to immediate antibiotic administration upon admission. Notably, most blood cultures for suspected early-onset neonatal sepsis do not yield a causative pathogen. This study aimed to assess polymerase chain reaction (PCR) [...] Read more.
Background: The high prevalence of suspected early-onset neonatal sepsis among preterm infants leads to immediate antibiotic administration upon admission. Notably, most blood cultures for suspected early-onset neonatal sepsis do not yield a causative pathogen. This study aimed to assess polymerase chain reaction (PCR) targeting the variable region V4 of the 16S ribosomal gene (16S rDNA) and Sanger sequencing for bacterial identification in preterm infants with suspected early-onset neonatal sepsis. Methods: Therefore, this prospective study was conducted. Preterm infants with suspected early-onset neonatal sepsis were included in this study. The three groups were formed based on the risk of infection and clinical sepsis. Blood samples were collected upon admission to the neonatal unit for culture and molecular analysis. PCR amplification and subsequent Sanger sequencing of the V4 region of the 16S rDNA were performed. Results: Twenty-eight patients were included in this study. Blood cultures were negative in 100% of the patients. Amplification and sequencing of the V4 region identified bacterial genera in 19 patients across distinct groups. The predominant taxonomically identified genus was Pseudomonas. Conclusions: Amplifying the 16S rDNA variable region through PCR and subsequent Sanger sequencing in preterm neonates with suspected early-onset neonatal sepsis can enhance the identification of microbial species that cause infection, especially in negative cultures. Full article
(This article belongs to the Special Issue Microbial Infections and Antimicrobial Use in Neonates and Infants)
11 pages, 771 KiB  
Article
Detection and Serological Evidence of European Bat Lyssavirus 1 in Belgian Bats between 2016 and 2018
by Inne Nauwelaers, Claudia Van den Eynde, Sanne Terryn, Bob Vandendriessche, Wout Willems, Daan Dekeukeleire and Steven Van Gucht
Trop. Med. Infect. Dis. 2024, 9(7), 151; https://doi.org/10.3390/tropicalmed9070151 - 5 Jul 2024
Viewed by 284
Abstract
Lyssaviruses are neurotropic viruses capable of inducing fatal encephalitis. While rabies virus has been successfully eradicated in Belgium, the prevalence of other lyssaviruses remains uncertain. In this study, we conducted a survey on live animals and passive surveillance to investigate the presence of [...] Read more.
Lyssaviruses are neurotropic viruses capable of inducing fatal encephalitis. While rabies virus has been successfully eradicated in Belgium, the prevalence of other lyssaviruses remains uncertain. In this study, we conducted a survey on live animals and passive surveillance to investigate the presence of lyssaviruses in Belgium. In 2018, a total of 113 saliva samples and 87 blood samples were collected from bats. Saliva was subjected to RT-qPCR to identify lyssavirus infections. Additionally, an adapted lyssavirus neutralisation assay was set up for the detection of antibodies neutralising EBLV-1 in blood samples. Furthermore, we examined 124 brain tissue samples obtained from deceased bats during passive surveillance between 2016 and 2018. All saliva samples tested negative for lyssaviruses. Analysis of the blood samples uncovered the presence of lyssavirus-neutralising antibodies in five bat species and 32% of samples with a wide range depending on bat species, suggesting past exposure to a lyssavirus. Notably, EBLV-1 was detected in brain tissue samples from two Eptesicus serotinus specimens collected in 2016 near Bertrix and 2017 near Étalle, confirming for the first time the presence of EBLV-1 in Belgium and raising awareness of the potential risks associated with this species of bats as reservoirs of the virus. Full article
(This article belongs to the Special Issue Treatment and Risk Assessment of Rabies)
13 pages, 220 KiB  
Article
A Qualitative Insight into Pre-Departure Orientation Training for Aspiring Nepalese Migrant Workers
by Pramod Regmi, Nirmal Aryal, Edwin van Teijlingen, Radheshyam Krishna KC, Manish Gautam and Sanju Maharjan
Trop. Med. Infect. Dis. 2024, 9(7), 150; https://doi.org/10.3390/tropicalmed9070150 - 5 Jul 2024
Viewed by 368
Abstract
Pre-departure orientation training (PDOT) can help equip aspiring migrant workers with skills and knowledge to mitigate vulnerabilities throughout their migration journey, including health. In Nepal, PDOT has been mandatory since 2004 for migrant workers awaiting labour permits. The current PDOT programme includes country-specific [...] Read more.
Pre-departure orientation training (PDOT) can help equip aspiring migrant workers with skills and knowledge to mitigate vulnerabilities throughout their migration journey, including health. In Nepal, PDOT has been mandatory since 2004 for migrant workers awaiting labour permits. The current PDOT programme includes country-specific information as well as health and well-being advice. However, the views of trainees and trainers on PDOT are largely unknown. This qualitative study aims to explore perceptions of migrant workers and relevant stakeholders on the content and delivery of PDOT. Six focus group discussions and six in-depth interviews were conducted with migrants, and eight interviews with key stakeholders were conducted. Thematic analysis resulted in five themes: (a) PDOT structure, accessibility, and implementation; (b) role of stakeholders in labour migration process; (c) coordination and governance; (d) curriculum development and relevance; and (e) capacity of trainers and effectiveness of training. Our findings emphasise the need for a more tailored curriculum with relevant information, education, and communication resources, possibly with input from former migrant workers. Regular updates of training topics and resources, as well as continued engagement with migrants after their employment, are essential for meeting the dynamic demands of the global employment market. Full article
(This article belongs to the Special Issue Contemporary Migrant Health, 2nd Edition)
11 pages, 554 KiB  
Article
High Frequency of Deletions in the pfhrp2 and pfhrp3 Genes of Plasmodium falciparum in the Middle Rio Negro Region of the Brazilian Amazon
by Daniela Romero Bally, Simone da Silva Santos, Diego Calafate Arregue, Mariana Kelly de Mattos and Martha C. Suárez-Mutis
Trop. Med. Infect. Dis. 2024, 9(7), 149; https://doi.org/10.3390/tropicalmed9070149 - 2 Jul 2024
Viewed by 485
Abstract
Several countries are reporting natural populations of P. falciparum with deletions in the pfhrp2/3 genes that can lead to false-negative results in rapid diagnostic tests. To investigate the prevalence of deletion in the pfhrp2/3 genes in the Rio Negro basin in [...] Read more.
Several countries are reporting natural populations of P. falciparum with deletions in the pfhrp2/3 genes that can lead to false-negative results in rapid diagnostic tests. To investigate the prevalence of deletion in the pfhrp2/3 genes in the Rio Negro basin in the Brazilian Amazon and identify whether there is clinical differentiation between individuals infected by these parasites, clinical samples collected from 2003 to 2016 were analyzed from symptomatic and asymptomatic P. falciparum-infected individuals. The molecular deletion of pfhrp2 and pfhrp3 genes was evaluated using the protocols recommended by the WHO. From 82 samples used, 28 (34.2%) had a single deletion in pfhrp2, 19 (23.2%) had a single deletion in pfhrp3, 15 (18.3%) had a double deletion (pfhrp2/3), and 20 (24.4%) did not have a deletion in either gene. In total, 29.3% of individuals had an asymptomatic plasmodial infection and were 3.64 times more likely to have parasites with a double deletion (pfhrp2/3) than patients with clinical malaria (p = 0.02). The high prevalence of parasites with pfhrp2/3 deletions shows the need to implement a surveillance program in this area. Deletions in parasites may be associated with the clinical pattern of the disease in this area. More studies must be carried out to elucidate these findings. Full article
(This article belongs to the Special Issue Advances in Molecular Diagnosis of Malaria)
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9 pages, 233 KiB  
Review
Antibiotic Chemoprophylaxis for Leptospirosis: Previous Shortcomings and Future Needs
by Kyle Petersen and Ashley Maranich
Trop. Med. Infect. Dis. 2024, 9(7), 148; https://doi.org/10.3390/tropicalmed9070148 - 2 Jul 2024
Viewed by 474
Abstract
Leptospirosis is a neglected tropical disease that remains potentially life threatening and hard to diagnose. Climate change combined with overlapping reservoir and human habitats will likely lead to increasing incidence, outbreaks, and mortality in the future. Preventative vaccines are either of limited scope [...] Read more.
Leptospirosis is a neglected tropical disease that remains potentially life threatening and hard to diagnose. Climate change combined with overlapping reservoir and human habitats will likely lead to increasing incidence, outbreaks, and mortality in the future. Preventative vaccines are either of limited scope and availability, or under development. Antibiotic chemoprophylaxis for prevention has been the subject of numerous clinical trials. However, despite 40 years of effort, clinical trials to better define protective efficacy, dosing, and the preferred medication are of poor quality and offer limited evidence. We reviewed the literature and offer critiques of the existing trials as well as potential areas for future exploration that may better define the epidemiology and yield a better evidence base for both travel medicine and public health efforts. Full article
14 pages, 5726 KiB  
Article
Incidence of Scrub Typhus according to Changes in Geographic and Demographic Characteristic in the Chungcheong Region of Korea
by Sungchan Yang, Gemma Park and Yuna Kim
Trop. Med. Infect. Dis. 2024, 9(7), 147; https://doi.org/10.3390/tropicalmed9070147 - 30 Jun 2024
Viewed by 323
Abstract
To ascertain the incidence trends of scrub typhus in the Chungcheong region, we analyzed the epidemiological survey information of 14,379 cases of scrub typhus reported to the integrated disease health management system of the Korea Centers for Disease Control and Prevention between 2012 [...] Read more.
To ascertain the incidence trends of scrub typhus in the Chungcheong region, we analyzed the epidemiological survey information of 14,379 cases of scrub typhus reported to the integrated disease health management system of the Korea Centers for Disease Control and Prevention between 2012 and 2022, along with demographic data from the Korean Statistics Information Service. Geographical analyses were performed to confirm the correlation between high-risk areas and the proportion of elderly people. The average age, proportion of elderly people, and changes in the agricultural population were statistically associated with incidence. The incidence of scrub typhus, and the agricultural population, in the Chungcheong region has decreased compared with that in 2012–2013. However, recent trends indicate a resurgence linked to increased outdoor activity, with higher risks observed in older age groups. Additionally, advancing age correlates with a heightened probability of reinfection and additional infections with other febrile diseases. The incidence of scrub typhus in the Chungcheong region (2012–2022) is changing according to age and route of infection, highlighting the need for revised prevention and promotion policies. Full article
(This article belongs to the Special Issue Infectious Disease Prevention and Control: A One Health Approach)
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9 pages, 328 KiB  
Article
Clinical Prediction Rules for In-Hospital Mortality Outcome in Melioidosis Patients
by Sunee Chayangsu, Chusana Suankratay, Apichat Tantraworasin and Jiraporn Khorana
Trop. Med. Infect. Dis. 2024, 9(7), 146; https://doi.org/10.3390/tropicalmed9070146 - 28 Jun 2024
Viewed by 190
Abstract
Background: Melioidosis, a disease induced by Burkholderia pseudomallei, poses a significant health threat in tropical areas where it is endemic. Despite the availability of effective treatments, mortality rates remain notably elevated. Many risk factors are associated with mortality. This study aims to [...] Read more.
Background: Melioidosis, a disease induced by Burkholderia pseudomallei, poses a significant health threat in tropical areas where it is endemic. Despite the availability of effective treatments, mortality rates remain notably elevated. Many risk factors are associated with mortality. This study aims to develop a scoring system for predicting the in-hospital mortality from melioidosis using readily available clinical data. Methods: The data were collected from Surin Hospital, Surin, Thailand, during the period from April 2014 to March 2017. We included patients aged 15 years and above who had cultures that tested positive for Burkholderia pseudomallei. The clinical prediction rules were developed using significant risk factors from the multivariable analysis. Results: A total of 282 patients with melioidosis were included in this study. In the final analysis model, 251 patients were used for identifying the significant risk factors of in-hospital fatal melioidosis. Five factors were identified and used for developing the clinical prediction rules, and the factors were as follows: qSOFA ≥ 2 (odds ratio [OR] = 2.39, p= 0.025), abnormal chest X-ray findings (OR = 5.86, p < 0.001), creatinine ≥ 1.5 mg/dL (OR = 2.80, p = 0.004), aspartate aminotransferase ≥50 U/L (OR = 4.032, p < 0.001), and bicarbonate ≤ 20 mEq/L (OR = 2.96, p = 0.002). The prediction scores ranged from 0 to 7. Patients with high scores (4–7) exhibited a significantly elevated mortality rate exceeding 65.0% (likelihood ratio [LR+] 2.18, p < 0.001) compared to the low-risk group (scores 0–3) with a lower mortality rate (LR + 0.18, p < 0.001). The area under the receiver operating characteristic curve (AUC) was 0.84, indicating good model performance. Conclusions: This study presents a simple scoring system based on easily obtainable clinical parameters to predict in-hospital mortality in melioidosis patients. This tool may facilitate the early identification of high-risk patients who could benefit from more aggressive treatment strategies, potentially improving clinical decision-making and patient outcomes. Full article
14 pages, 3085 KiB  
Article
Experimental Granulomatous Amebic Encephalitis Caused by Acanthamoeba castellanii
by Samuel da Luz Borges, Eberson da Silva de Macedo, Felipe Alexandre Vinagre da Silva, Brenda Jaqueline de Azevedo Ataíde, Nívia de Souza Franco Mendes, Adelaide da Conceição Fonseca Passos, Suellen Alessandra Soares de Moraes, Anderson Manoel Herculano, Karen Renata Herculano Matos Oliveira, Carlomagno Pacheco Bahia, Silvio Santana Dolabella and Evander de Jesus Oliveira Batista
Trop. Med. Infect. Dis. 2024, 9(7), 145; https://doi.org/10.3390/tropicalmed9070145 - 28 Jun 2024
Viewed by 317
Abstract
Acanthamoeba genus can affect humans with diseases such as granulomatous amebic encephalitis (GAE), a highly lethal neuroinfection. Several aspects of the disease still need to be elucidated. Animal models of GAE have advanced our knowledge of the disease. This work tested Wistar rats [...] Read more.
Acanthamoeba genus can affect humans with diseases such as granulomatous amebic encephalitis (GAE), a highly lethal neuroinfection. Several aspects of the disease still need to be elucidated. Animal models of GAE have advanced our knowledge of the disease. This work tested Wistar rats (Rattus norvegicus albinus) as an animal model of GAE. For this, 32 animals were infected with 1 × 106 A. castellanii trophozoites of the T4 genotype. Ameba recovery tests were carried out using agar plates, vascular extravasation assays, behavioral tests, and histopathological technique with H/E staining. Data were subjected to linear regression analysis, one-way ANOVA, and Tukey’s test, performed in the GraphPad Prism® 8.0 program, with a significance level of p < 0.05. The results revealed the efficiency of the model. Amebae were recovered from the liver, lungs, and brain of infected animals, and there were significant encephalic vascular extravasations and behavioral changes in these animals, but not in the control animals. However, not all infected animals showed positive histopathology for the analyzed organs. Nervous tissues were the least affected, demonstrating the role of the BBB in the defense of the CNS. Supported by the demonstrated evidence, we confirm the difficulties and the feasibilities of using rats as an animal model of GAE. Full article
(This article belongs to the Special Issue Advances in Parasitic Neglected Tropical Diseases)
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12 pages, 222 KiB  
Article
Challenges of Screening and Investigations of Contacts of Patients with Tuberculosis in Oyo and Osun States, Nigeria
by Aderonke Agbaje, Patrick Dakum, Olugbenga Daniel, Anyaike Chukwuma, Obioma Chijoke-Akaniro, Evaezi Okpokoro, Samuel Akingbesote, Christian Anyomi, Adekola Adekunle, Abiola Alege, Moroof Gbadamosi, Olutunde Babalola, Charles Mensah, Rupert Eneogu, Austin Ihesie and Ademola Adelekan
Trop. Med. Infect. Dis. 2024, 9(7), 144; https://doi.org/10.3390/tropicalmed9070144 - 28 Jun 2024
Viewed by 359
Abstract
Tuberculosis (TB) remains a significant public health challenge in Nigeria, with high rates of transmission and low case detection rates. This paper presents the challenges of screening and investigation of contacts of patients with TB in Oyo and Osun State, Nigeria. This descriptive-qualitative [...] Read more.
Tuberculosis (TB) remains a significant public health challenge in Nigeria, with high rates of transmission and low case detection rates. This paper presents the challenges of screening and investigation of contacts of patients with TB in Oyo and Osun State, Nigeria. This descriptive-qualitative study was conducted in eight Local Government Areas with high TB burdens. Twenty-four focus group discussions and 30 key informant interviews were conducted among TB patients, household TB contacts, and government TB staff, among others. Respondents ages ranged from 17–85 years with a mean of 42.08 ± 14.9 years, and (4.0%) had a postgraduate degree. This study identified that the majority of TB contacts who tested negative for TB were unwilling to be placed on TB preventive therapy because of the belief that only a sick person should take drugs. Also, hostility from the TB contacts to the contact tracers during the house-to-house screening of presumptive TB cases due to community stigma associated with TB was another existing gap reported in TB contact investigations. The findings emphasise the importance of tailored approaches in TB prevention and control, addressing challenges in testing and contact investigations; this necessitates investments in community engagement strategies to enhance the cooperation of TB contacts. Full article
(This article belongs to the Section Infectious Diseases)
13 pages, 1090 KiB  
Article
One Health Approach to Toxoplasmosis: Owner and Dog Seropositivity as Spatial Indicators of Risk Areas for Acquired, Gestational and Congenital Transmission
by Natacha Sohn-Hausner, Ricardo Guedes Correa, Louise Bach Kmetiuk, Evelyn Cristine da Silva, Gustavo Nunes de Moraes, Gabrielle dos Santos Rocha, Helio Langoni and Alexander Welker Biondo
Trop. Med. Infect. Dis. 2024, 9(7), 143; https://doi.org/10.3390/tropicalmed9070143 - 28 Jun 2024
Viewed by 475
Abstract
Background: Toxoplasmosis has been of public health concern due to direct associations with socioeconomic vulnerability and inadequate living conditions. Methods: Accordingly, the present study aimed to assess antibodies against T. gondii, historical reported toxoplasmosis cases and associated socio-environmental risk factors in Pinhais, [...] Read more.
Background: Toxoplasmosis has been of public health concern due to direct associations with socioeconomic vulnerability and inadequate living conditions. Methods: Accordingly, the present study aimed to assess antibodies against T. gondii, historical reported toxoplasmosis cases and associated socio-environmental risk factors in Pinhais, a full urban area of Curitiba, currently the eighth biggest metropolitan area of Brazil. Anti-Toxoplasma gondii antibodies were assessed by an indirect immunofluorescence reaction (RIFI). Owner and dog samples were also tested by IFAT to anti-Leishmania spp. and anti-Trypanosoma cruzi antibodies. Results: Overall, 20/135 (14.8%) persons and 13/133 (9.8%) dogs from 25 different households were considered seropositive to T. gondii. All samples were seronegative to Leishmania spp. and Trypanosoma cruzi. Conclusions: Although no significant covariates were found in the regression model, statistically associated risk factors in the bivariate analysis included no public water use (p = 0.016) and drinking raw milk (p = 0.041) for owners, and obesity (p = 0.028) and tick infestation (p = 0.03) for dogs. In addition, a spatial cluster of T. gondii seropositivity for both owners and their dogs overlapped the location of historic reported cases of human acquired, gestational and congenital toxoplasmosis. Finally, the results herein showed tick infestation as an indicator of socio-environmental risk for T. gondii exposure in the household environment, and dogs may be used as sentinels for human toxoplasmosis cases. Full article
(This article belongs to the Section One Health)
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13 pages, 831 KiB  
Article
Evaluation of Bait Acceptance and Immune Response in Local Dogs during an Oral Rabies Vaccination Field Study in Morocco
by Nadia Aboulfidaa, Florence Cliquet, Emmanuelle Robardet, Sami Darkaoui, Marine Wasniewski, Christian Kaiser, Katharina Bobe, Ad Vos and Ouafaa Fassi Fihri
Trop. Med. Infect. Dis. 2024, 9(7), 142; https://doi.org/10.3390/tropicalmed9070142 - 26 Jun 2024
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Abstract
The objective of this study was to evaluate the bait preference of three selected bait types by local dogs and the induced immunogenicity of the oral rabies vaccine strain SPBN GASGAS in Morocco. The vaccine strain, combined with different bait types, has been [...] Read more.
The objective of this study was to evaluate the bait preference of three selected bait types by local dogs and the induced immunogenicity of the oral rabies vaccine strain SPBN GASGAS in Morocco. The vaccine strain, combined with different bait types, has been tested in many different settings, but not yet in northern Africa. Overall, bait consumption and preference were similar in other studies using the same materials (bait type and sachet). The intestine bait had the highest acceptance rate (97.6%, 95%CI: 87.4–99.9), followed by the egg bait (83.0%, 95%CI: 69.2–92.4). Only 52% (95%CI: 37.4–66.3) of the dogs showed an interest in the fish meal bait. However, considering the successful release of the contents of the sachet (blue-dyed water) into the oral cavity, the egg bait (65.7%, 95%CI: 47.8–80.9) scored better than the intestine bait (51.7%, 95%CI: 32.5–70.6). The dogs selected for the immunogenicity study were offered the egg bait containing a sachet filled with SPBN GASGAS (3.0 mL, 107.5 FFU/mL) or were given the same dose by direct oral administration (d.o.a.). In addition, several dogs were vaccinated by the parenteral route (s.c.) using a commercially available inactivated rabies vaccine. Unfortunately, due to the COVID-19 pandemic and subsequent travel restrictions, it was not possible to collect blood samples directly after vaccination. The blood samples were collected pre-vaccination and on five occasions between 450 and 1088 days post vaccination. The seroconversion rate, as determined for rabies-virus-neutralizing antibodies by the FAVN test, was significantly lower than that found for binding antibodies, as determined by ELISA, for all blood samples collected post vaccination. No treatment effect (bait, d.o.a., s.c.) could be seen in the seroconversion rate. At 15 months post vaccination, 84.2% of the dogs offered vaccine bait still tested sero-positive in ELISA. Only after 3 years was a clear drop in the seroconversion rate observed in all three treatment groups. This study confirms the long-term immunogenicity of the oral rabies vaccine SPBN GASGAS in dogs under field conditions. Full article
(This article belongs to the Special Issue Treatment and Risk Assessment of Rabies)
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12 pages, 1316 KiB  
Article
Consistency of Multi-Month Antiretroviral Therapy Dispensing and Association with Viral Load Coverage among Pediatric Clients Living with HIV in Mozambique
by Ivete Meque, Nicole Herrera, Michelle M. Gill, Rui Guilaze, Amancio Nhangave, Jaciara Mussá, Nilesh Bhatt, Mahoudo Bonou and Lauren Greenberg
Trop. Med. Infect. Dis. 2024, 9(7), 141; https://doi.org/10.3390/tropicalmed9070141 - 26 Jun 2024
Viewed by 1147
Abstract
With the increase in uptake of multi-month antiretroviral therapy dispensing (MMD) for children, little is known about consistency of MMD receipt over time and its association with virological outcomes. This analysis aims to assess the uptake of 3-month MMD among children, consistent receipt [...] Read more.
With the increase in uptake of multi-month antiretroviral therapy dispensing (MMD) for children, little is known about consistency of MMD receipt over time and its association with virological outcomes. This analysis aims to assess the uptake of 3-month MMD among children, consistent receipt of MMD after uptake, and clinical outcomes following transition to MMD in 16 health facilities in Gaza and Inhambane Provinces. This is a secondary analysis involving children <15 years living with HIV with clinical visits during the period from September 2019 to August 2020. Of 4383 children, 82% ever received MMD (at least one pickup of a 3-month MMD supply) during the study period but only 40% received it consistently (defined as MMD at every visit during the study period). Consistent MMD was most common among older children and children without indications of clinical instability. Overall viral load (VL) coverage was 40% (733/1851). Consistent MMD was significantly associated with lower odds of having a VL (0.78, 95% CI: 0.64–0.95). In conclusion, while receipt of a multi-month supply was common particularly during the early days of the COVID-19 pandemic, only a minority of children received consistent MMD; however, there is a need to ensure children with fewer visits still receive timely VL monitoring. Full article
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16 pages, 1570 KiB  
Article
Identification and Functional Implications of the E5 Oncogene Polymorphisms of Human Papillomavirus Type 16
by Antônio Humberto P. da Silva-Júnior, Ruany Cristyne de Oliveira Silva, Ana Pavla A. Diniz Gurgel, Marconi Rêgo Barros-Júnior, Kamylla Conceição Gomes Nascimento, Daffany Luana Santos, Lindomar J. Pena, Rita de Cássia Pereira Lima, Marcus Vinicius de Aragão Batista, Bárbara Simas Chagas and Antonio Carlos de Freitas
Trop. Med. Infect. Dis. 2024, 9(7), 140; https://doi.org/10.3390/tropicalmed9070140 - 26 Jun 2024
Viewed by 680
Abstract
The persistence of the human papillomavirus type 16 (HPV16) infection on the cervical epithelium contributes to the progression of cervical cancer. Studies have demonstrated that HPV16 genetic variants may be associated with different risks of developing cervical cancer. However, the E5 oncoprotein of [...] Read more.
The persistence of the human papillomavirus type 16 (HPV16) infection on the cervical epithelium contributes to the progression of cervical cancer. Studies have demonstrated that HPV16 genetic variants may be associated with different risks of developing cervical cancer. However, the E5 oncoprotein of HPV16, which is related to several cellular mechanisms in the initial phases of the infection and thus contributes to carcinogenesis, is still little studied. Here we investigate the HPV16 E5 oncogene variants to assess the effects of different mutations on the biological function of the E5 protein. We detected and analyzed the HPV16 E5 oncogene polymorphisms and their phylogenetic relationships. After that, we proposed a tertiary structure analysis of the protein variants, preferential codon usage, and functional activity of the HPV16 E5 protein. Intra-type variants were grouped in the lineages A and D using in silico analysis. The mutations in E5 were located in the T-cell epitopes region. We therefore analyzed the interference of the HPV16 E5 protein in the NF-kB pathway. Our results showed that the variants HPV16E5_49PE and HPV16E5_85PE did not increase the potential of the pathway activation capacity. This study provides additional knowledge about the mechanisms of dispersion of the HPV16 E5 variants, providing evidence that these variants may be relevant to the modulation of the NF-κB signaling pathway. Full article
(This article belongs to the Special Issue Molecular Epidemiology of Human Papillomavirus Infection)
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11 pages, 3137 KiB  
Article
Investigating the Diagnostic and Therapeutic Potential of a T Cell Receptor (TCR)-like single Domain Antibody (sDAb)-Human IgG1 Antibody against Heat Shock Protein (HSP) 16KDa/HLA-A2 for Latent Tuberculosis
by Huaqiang Liu, Sylvia Annabel Dass, Matthew Tze Jian Wong, Venugopal Balakrishnan, Fazlina Nordin and Gee Jun Tye
Trop. Med. Infect. Dis. 2024, 9(7), 139; https://doi.org/10.3390/tropicalmed9070139 - 26 Jun 2024
Viewed by 722
Abstract
Heat shock protein 16-kDa (HSP 16-kDa) is essential for the survival of Mycobacterium tuberculosis (M. tuberculosis) during the latent period; hence, a peptide–MHC presentation of HSP 16-kDa could be a potential diagnostic and therapeutic target for latent tuberculosis (LTB). This study [...] Read more.
Heat shock protein 16-kDa (HSP 16-kDa) is essential for the survival of Mycobacterium tuberculosis (M. tuberculosis) during the latent period; hence, a peptide–MHC presentation of HSP 16-kDa could be a potential diagnostic and therapeutic target for latent tuberculosis (LTB). This study aimed to generate a TCR-like single-domain antibody (sDAb)-human IgG1 antibody and subsequently investigate its diagnostic and therapeutic potential in LTB, utilizing a model cell presenting the target peptide. A previously generated TCR-like sDAB that can bind to HSP 16-kDa was first fused to a human IgG1 Fc-receptor via a linker. The fusion product, sDAb-IgG1, was expressed with HEK293-F and was subsequently purified. Its diagnostic potential was investigated via cell-based ELISA utilizing MCF-7 cells peptide-pulsed with HSP 16-kDa peptides. Investigation into the antibody-dependent cell-mediated cytotoxicity (ADCC) of MCF-7 cells was also conducted to investigate its therapeutic potential. Finally, TCR-like sDAb-IgG1 was successfully produced transiently with HEK-293F and was purified using protein A chromatography. The generated antibody was tested using cell-based ELISA, which demonstrated the effective binding of the TCR-like sDAb-IgG1 to the 16-kDa peptide–MHC on the cell surface. The ADCC assay also showed that the antibody effectively mediated the ADCC of MCF-7 cells with the help of 16-kDa peptide–MHC. This allows us to hypothesize the possible utility of the said antibody for both diagnostics and therapeutics of latent tuberculosis after more investigations with clinical samples. Full article
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