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Trop. Med. Infect. Dis., Volume 4, Issue 3 (September 2019)

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Open AccessReview
Check the Ear. The Importance of Ear Examinations in Assessment of Intracranial Subdural Empyema
Trop. Med. Infect. Dis. 2019, 4(3), 120; https://doi.org/10.3390/tropicalmed4030120 - 18 Sep 2019
Viewed by 299
Abstract
Intracranial subdural empyema (ISE) is an uncommon condition previously associated with almost 100% morbidity and mortality. Since the introduction of antibiotics and advancements in diagnosis the complication rates have significantly improved. We report an unusual case of a 32-year-old Aboriginal male diagnosed with [...] Read more.
Intracranial subdural empyema (ISE) is an uncommon condition previously associated with almost 100% morbidity and mortality. Since the introduction of antibiotics and advancements in diagnosis the complication rates have significantly improved. We report an unusual case of a 32-year-old Aboriginal male diagnosed with ISE. On closer inspection the ISE was found to be a complication of otitis media with a cotton bud lodged in the external acoustic meatus. The report provides a literature review on the relationships of ISE, otitis media and foreign bodies. We conclude that although rare, all patients with suspected ISE should undergo an ear examination as it is at no cost to the patient or health service but may be the difference between life and death. Full article
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Open AccessReview
A Decade of Avian Influenza in Bangladesh: Where Are We Now?
Trop. Med. Infect. Dis. 2019, 4(3), 119; https://doi.org/10.3390/tropicalmed4030119 - 11 Sep 2019
Viewed by 449
Abstract
Highly pathogenic avian influenza (HPAI) has been a public health threat in Bangladesh since the first reported outbreak in poultry in 2007. The country has undertaken numerous efforts to detect, track, and combat avian influenza viruses (AIVs). The predominant genotype of the H5N1 [...] Read more.
Highly pathogenic avian influenza (HPAI) has been a public health threat in Bangladesh since the first reported outbreak in poultry in 2007. The country has undertaken numerous efforts to detect, track, and combat avian influenza viruses (AIVs). The predominant genotype of the H5N1 viruses is clade 2.3.2.1a. The persistent changing of clades of the circulating H5N1 strains suggests probable mutations that might have been occurring over time. Surveillance has provided evidence that the virus has persistently prevailed in all sectors and caused discontinuous infections. The presence of AIV in live bird markets has been detected persistently. Weak biosecurity in the poultry sector is linked with resource limitation, low risk perception, and short-term sporadic interventions. Controlling avian influenza necessitates a concerted multi-sector ‘One Health’ approach that includes the government and key stakeholders. Full article
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Open AccessArticle
Development of a Non-Meat-Based, Mass Producible and Effective Bait for Oral Vaccination of Dogs against Rabies in Goa State, India
Trop. Med. Infect. Dis. 2019, 4(3), 118; https://doi.org/10.3390/tropicalmed4030118 - 04 Sep 2019
Viewed by 547
Abstract
Introduction: To achieve the global goal of canine-mediated human rabies elimination by 2030 there is an urgent need to scale-up mass dog vaccination activities in regions with large dog populations that are difficult to access; a common situation in much of India. Oral [...] Read more.
Introduction: To achieve the global goal of canine-mediated human rabies elimination by 2030 there is an urgent need to scale-up mass dog vaccination activities in regions with large dog populations that are difficult to access; a common situation in much of India. Oral rabies vaccination may enable the vaccination of free-roaming dogs that are inaccessible to parenteral vaccination, and is considered a promising complementary measure to parenteral mass dog vaccination campaigns. WHO and OIE have published detailed minimum requirements for rabies vaccines and baits to be used for this purpose, requiring that baits must not only be well-accepted by the target population but must also efficiently release the vaccine in the oral cavity. For oral rabies vaccination approaches to be successful, it is necessary to develop baits which have a high uptake by the target population, are culturally accepted and amenable to mass production. The aim of this study was to compare the interest and uptake rates of meat-based and an egg-based prototype bait constructs by free roaming dogs in Goa, India. Methods: Three teams randomly distributed two prototype baits; an egg-flavoured bait and a commercial meat dog food (gravy) flavoured bait. The outcomes of consumption were recorded and compared between baits and dog variables. Results: A total of 209 egg-bait and 195 gravy-bait distributions were recorded and analysed. No difference (p = 0.99) was found in the percentage of dogs interested in the baits when offered. However, significantly more dogs consumed the egg-bait than the gravy-bait; 77.5% versus 68.7% (p = 0.04). The release of the blue-dyed water inside the sachet in the oral cavity of the animals was significant higher in the dogs consuming an egg-bait compared to the gravy-bait (73.4% versus 56.7%, p = 0.001). Conclusions: The egg-based bait had a high uptake amongst free roaming dogs and also enabled efficient release of the vaccine in the oral cavity, whilst also avoiding culturally relevant materials of bovine or porcine meat products. Full article
(This article belongs to the Special Issue Lyssaviruses and Rabies: Prevention, Control and Elimination)
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Open AccessArticle
Geographical Distribution of β-Lactam Resistance among Klebsiella spp. from Selected Health Facilities in Ghana
Trop. Med. Infect. Dis. 2019, 4(3), 117; https://doi.org/10.3390/tropicalmed4030117 - 03 Sep 2019
Viewed by 510
Abstract
β-Lactam-resistant Klebsiella isolates continue to cause multidrug resistance infections worldwide. This study aimed to describe the geographical distribution of extended spectrum β-lactamase (ESBL), AmpC β-lactamase (AmpC), and carbapenemase production among 139 Klebsiella isolates recovered from patients at major referral health facilities in Ghana. [...] Read more.
β-Lactam-resistant Klebsiella isolates continue to cause multidrug resistance infections worldwide. This study aimed to describe the geographical distribution of extended spectrum β-lactamase (ESBL), AmpC β-lactamase (AmpC), and carbapenemase production among 139 Klebsiella isolates recovered from patients at major referral health facilities in Ghana. The phenotypic methods of combined disc diffusion test, modified three-dimensional test, modified Hodge test (MHT), and combined disc test were performed for each isolate to detect ESBL, AmpC, carbapenemase, and metallo-β-lactamase (MBL) producers, respectively. Except for MBL, all other β-lactam resistance mechanisms were highest in the healthcare facilities situated in the northern belt of Ghana. Significant regional difference of ESBL producers was observed between the northern and middle belts as well as the northern and southern belts. Genotypic detection with polymerase chain reaction (PCR) revealed the presence of bla TEM 36/139 (25.9%), bla SHV 40/139 (28.8%), bla CTX-M 37/139 (26.6%), bla OXA-48 3/139 (2.16%), and bla NDM 1/139 (0.72%) genotypes. In conclusion, there were variations in β-lactam resistance among Klebsiella spp. from health facilities situated in the northern, middle, and southern belts of Ghana. The study provides preliminary evidence that emphasizes the need to direct more attention to antimicrobial resistance control, especially in the northern belt of Ghana. Findings from this study may be critical for creating and fine-tuning effective antimicrobial resistance control strategies and for informing accurate antibiotic prescription by practitioners. Full article
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Open AccessArticle
Evidence of West Nile Virus (WNV) Circulation in Wild Birds and WNV RNA Negativity in Mosquitoes of the Danube Delta Biosphere Reserve, Romania, 2016
Trop. Med. Infect. Dis. 2019, 4(3), 116; https://doi.org/10.3390/tropicalmed4030116 - 21 Aug 2019
Viewed by 624
Abstract
West Nile virus (WNV) is a zoonotic flavivirus whose transmission cycle in nature includes wild birds as amplifying hosts and ornithophilic mosquito vectors. Bridge vectors can transmit WNV to mammal species potentially causing West Nile Fever. Wild bird migration is a mode of [...] Read more.
West Nile virus (WNV) is a zoonotic flavivirus whose transmission cycle in nature includes wild birds as amplifying hosts and ornithophilic mosquito vectors. Bridge vectors can transmit WNV to mammal species potentially causing West Nile Fever. Wild bird migration is a mode of WNV introduction into new areas. The Danube Delta Biosphere Reserve (DDBR) is a major stopover of wild birds migrating between Europe and Africa. The aim of this study was to investigate the presence of WNV in the DDBR during the 2016 transmission season in wild birds and mosquitoes. Blood from 68 wild birds (nine different species) trapped at four different locations was analyzed by competitive ELISA and Virus Neutralization Test (VNT), revealing positive results in 8/68 (11.8%) of the wild birds by ELISA of which six samples (three from juvenile birds) were confirmed seropositive by VNT. Mosquitoes (n = 6523, 5 genera) were trapped with CDC Mini Light traps at two locations and in one location resting mosquitoes were caught. The presence of WNV RNA was tested in 134 pools by reverse transcription quantitative PCR (RT-qPCR). None of the pools was positive for WNV-specific RNA. Based on the obtained results, WNV was circulating in the DDBR during 2016. Full article
(This article belongs to the Special Issue Recent Advancements on Arthropod-Borne Infectious Diseases)
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Open AccessArticle
Dog Owners’ Knowledge about Rabies and Other Factors That Influence Canine Anti-Rabies Vaccination in the Upper East Region of Ghana
Trop. Med. Infect. Dis. 2019, 4(3), 115; https://doi.org/10.3390/tropicalmed4030115 - 18 Aug 2019
Viewed by 545
Abstract
Background: Human rabies, often contracted through dog bites, is a serious but neglected public health problem in the tropics, including Ghana. Due to its high fatality rate, adequate knowledge and vaccination of domestic dogs against the disease are very crucial in reducing its [...] Read more.
Background: Human rabies, often contracted through dog bites, is a serious but neglected public health problem in the tropics, including Ghana. Due to its high fatality rate, adequate knowledge and vaccination of domestic dogs against the disease are very crucial in reducing its burden. We examined dog owners’ knowledge level on rabies and factors that influenced anti-rabies vaccination of dogs in the Upper East Region of Ghana. Methods: This descriptive cross-sectional study was conducted among 260 randomly sampled dog owners in six communities from six Districts using a multistage sampling technique, in the Upper East Region of Ghana. An interviewer-administered questionnaire was used to collect data from the respondents. Descriptive and inferential analyses were done using STATA 14.1. Results: While knowledge about rabies was 199 (76.5%), that about anti-rabies vaccination was 137 (52.7%). District of residence (χ2 = 112.59, p < 0.001), sex (χ2 = 6.14, p = 0.013), education (χ2 = 20.45, p < 0.001) as well as occupation (χ2 = 11.97, p = 0.007) were significantly associated with rabies knowledge. District of residence (χ2 = 57.61, p < 0.001), Educational level (χ2 = 15.37, p = 0.004), occupation (χ2 = 11.66, p = 0.009), religion (χ2 = 8.25, p = 0.016) and knowledge on rabies (χ2 = 42.13, p < 0.001) were also statistically associated with dog vaccination against rabies. Dog owners with good knowledge on rabies for instance, were more likely to vaccinate their dogs against rabies compared to those with poor knowledge [AOR = 1.99 (95% CI: 0.68, 5.86), p = 0.210]. Dog owners with tertiary level of education were also 76.31 times more likely (95% CI: 6.20, 938.49, p = 0.001) to have good knowledge about rabies compared to those with no formal education. Conclusions: Dog owners in the Upper East Region of Ghana had good knowledge about rabies. This, however, did not translate into correspondingly high levels of dog vaccination against the disease. Rabies awareness and vaccination campaigns should, therefore, be intensified in the region, especially among the least educated and female dog owners. Full article
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Open AccessArticle
Counting Oceanians of Non-European, Non-Asian Descent (ONENA) in the South Pacific to Make Them Count in Global Health
Trop. Med. Infect. Dis. 2019, 4(3), 114; https://doi.org/10.3390/tropicalmed4030114 - 09 Aug 2019
Cited by 1 | Viewed by 577
Abstract
Several diseases and vulnerabilities associated with genetic or microbial factors are more frequent among populations of Oceanian, Non-European, Non-Asian descent (ONENA). ONENA are specific and have long been isolated geographically. To our knowledge, there are no published official, quantitative, aggregated data on the [...] Read more.
Several diseases and vulnerabilities associated with genetic or microbial factors are more frequent among populations of Oceanian, Non-European, Non-Asian descent (ONENA). ONENA are specific and have long been isolated geographically. To our knowledge, there are no published official, quantitative, aggregated data on the populations impacted by these excess vulnerabilities in Oceania. We searched official census reports for updated estimates of the total population for each of the Pacific Island Countries and Territories (including Australia) and the US State of Hawaii, privileging local official statistical or censual sources. We multiplied the most recent total population estimate by the cumulative percentage of the ONENA population as determined in official reports. Including Australia and the US State of Hawaii, Oceania counts 27 countries and territories, populated in 2016 by approximately 41 M inhabitants (17 M not counting Australia) among which approximately 12.5 M (11.6 M not counting Australia) consider themselves of entire or partial ONENA ancestry. Specific genetic and microbiome traits of ONENA may be unique and need further investigation to adjust risk estimates, risk prevention, diagnostic and therapeutic strategies, to the benefit of populations in the Pacific and beyond. Full article
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Open AccessArticle
Assessment of a Sensitive qPCR Assay Targeting a Multiple-Copy Gene to Detect Orientia tsutsugamushi DNA
Trop. Med. Infect. Dis. 2019, 4(3), 113; https://doi.org/10.3390/tropicalmed4030113 - 31 Jul 2019
Viewed by 557
Abstract
Scrub typhus is caused by an obligated intracellular organism, Orientia tsutsugamushi (Orientia). The disease was traditionally thought to be limited in the tsutsugamushi triangle. Recently, scrub typhus has been confirmed in areas outside the triangle. Serological diagnosis of scrub typhus relies [...] Read more.
Scrub typhus is caused by an obligated intracellular organism, Orientia tsutsugamushi (Orientia). The disease was traditionally thought to be limited in the tsutsugamushi triangle. Recently, scrub typhus has been confirmed in areas outside the triangle. Serological diagnosis of scrub typhus relies on indirect immunofluorescence assay (IFA). Molecular assays such as PCR, qPCR, loop-mediated isothermal amplification, and recombinase polymerase amplification are often targeting a single copy gene. These assays are sensitive and specific, yet they are not broadly used in clinical settings possibly due to low circulating Orientia in blood. In this study, we compared qPCR results using a multiple copy (traD) gene with those using a single copy (47 kDa) gene to assess the improvement of sensitivity and limit of detection. Our results demonstrate that the qPCR using the traD gene provides superior sensitivity in 15 Orientia strains. The limit of detection is below single Orientia genome equivalent and the assay retains specificity with excessive DNA from mouse, chiggers and human. The clinical utility was evaluated using confirmed scrub typhus positive and negative samples. The results show 100% sensitivity and specificity in these samples suggesting that the traD gene qPCR may be useful for clinical diagnosis of Orientia infection. Full article
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Open AccessArticle
Helminthiasis among School-Age Children and Hygiene Conditions of Selected Schools in Lafia, Nasarawa State, Nigeria
Trop. Med. Infect. Dis. 2019, 4(3), 112; https://doi.org/10.3390/tropicalmed4030112 - 29 Jul 2019
Viewed by 644
Abstract
The burden of soil-transmitted helminths (STHs) infections in Nigeria is enormous with serious public health significance. This study, therefore, assessed helminthiasis among school-age children and the hygiene conditions of schools in Lafia, Nasarawa State, Nigeria between December 2015 and April 2016 from four [...] Read more.
The burden of soil-transmitted helminths (STHs) infections in Nigeria is enormous with serious public health significance. This study, therefore, assessed helminthiasis among school-age children and the hygiene conditions of schools in Lafia, Nasarawa State, Nigeria between December 2015 and April 2016 from four randomly selected primary schools. Stool samples were collected from 200 primary school pupils including 80 males (40%) and 120 females (60%) between five and 16 years, using clean sample bottles and a standard parasitology examination technique at the central laboratory at the Federal University, Lafia. An overall prevalence of 33.5% (67/200) helminths infections was recorded. A checklist of Ascaris lumbricoides, hookworm, Trichuris trichiura, and Strongyloides stercoralis was generated from the pooled data of the four studied schools in which A. lumbricoides occurred highest with 13% (26/200) while S. stercoralis was the least prevalent at 2.50% (5/200). Among the schools sampled, St. James Pilot Science Primary School’s children were the most infected at 44% (22/50). Multiple infections were observed in three of the four schools sampled. There was no significant difference (p > 0.05) in prevalence rates of different STHs infections in relation to age group and gender across schools. Our findings showed that the hygiene conditions in the studied schools were poor without water, hand washing materials, refuse bins, as well as poor sanitary conditions. This study also identified ova and larvae of STHs parasites in the analyzed soil samples from the studied schools. Most school-age children had knowledge about contamination but few among them washed their hands with water and soap. The obtained result indicated a negative association between the prevalence of STHs and the proportion of pupils that cleaned up with water after defection. We, therefore, advise that hygiene conditions in schools be improved and that the government should prioritize enrolling all primary schools in Nasarawa state for the school health program so as to reduce the burden of STHs among school-age children in the state. Full article
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Open AccessArticle
Comparison of Two Commercial ELISA Kits for the Detection of Anti-Dengue IgM for Routine Dengue Diagnosis in Laos
Trop. Med. Infect. Dis. 2019, 4(3), 111; https://doi.org/10.3390/tropicalmed4030111 - 25 Jul 2019
Viewed by 573
Abstract
The endemicity of Dengue virus (DENV) infection remains a major public health problem in Lao PDR. In this study, we compared two commercial anti-dengue IgM ELISA kits, Panbio® Dengue IgM Capture ELISA (Panbio Kit, Alere, Waltham, MA, USA) and DEN DetectTM [...] Read more.
The endemicity of Dengue virus (DENV) infection remains a major public health problem in Lao PDR. In this study, we compared two commercial anti-dengue IgM ELISA kits, Panbio® Dengue IgM Capture ELISA (Panbio Kit, Alere, Waltham, MA, USA) and DEN DetectTM MAC-ELISA (InBios kit, InBios International, Inc., Seattle, WA, USA), in the context of diagnosis of patients admitted to hospital with clinical dengue presentation. Two panels of paired blood samples were tested. Panel A was composed of 54 dengue confirmed patients (by DENV real-time RT-PCR) and 11 non-dengue dengue patients (other infections confirmed by corresponding PCR results). Panel B included 74 patients randomly selected from consecutive patients admitted to Mahosot Hospital in 2008 with suspicion of dengue fever according to WHO criteria. Results from panel A showed significantly better sensitivity for Panbio kit (64.8%; 95%CI: 50.6–77.3%) than for InBios kit (18.5%; 95%CI: 9.3–31.4%) when testing admission sera. Sensitivity was increased for both kits when combining results from admission and convalescent sera. Concordant results were obtained from panel B with fair agreement (κ = 0.29) between both kits when testing single admission samples, and moderate agreement (κ = 0.5) when combining results from admission and convalescent sera. Full article
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Open AccessArticle
Prevalence and Risk Factors for Schistosomiasis among Schoolchildren in two Settings of Côte d’Ivoire
Trop. Med. Infect. Dis. 2019, 4(3), 110; https://doi.org/10.3390/tropicalmed4030110 - 23 Jul 2019
Viewed by 528
Abstract
Schistosomiasis is a parasitic disease affecting more than 250 million people, primarily in sub-Saharan Africa. In Côte d’Ivoire both Schistosoma haematobium (causing urogenital schistosomiasis) and Schistosoma mansoni (causing intestinal schistosomiasis) co-exist. This study aimed to determine the prevalence of S. haematobium and S. [...] Read more.
Schistosomiasis is a parasitic disease affecting more than 250 million people, primarily in sub-Saharan Africa. In Côte d’Ivoire both Schistosoma haematobium (causing urogenital schistosomiasis) and Schistosoma mansoni (causing intestinal schistosomiasis) co-exist. This study aimed to determine the prevalence of S. haematobium and S. mansoni and to identify risk factors among schoolchildren in the western and southern parts of Côte d’Ivoire. From January to April 2018, a cross-sectional study was carried out including 1187 schoolchildren aged 5–14 years. Urine samples were examined by a filtration method to identify and count S. haematobium eggs, while stool samples were subjected to duplicate Kato-Katz thick smears to quantify eggs of S. mansoni and soil-transmitted helminths. Data on sociodemographic, socioeconomic, and environmental factors were obtained using a pretested questionnaire. Multivariate logistic regression was employed to test for associations between variables. We found a prevalence of S. haematobium of 14.0% (166 of 1187 schoolchildren infected) and a prevalence of S. mansoni of 6.1% (66 of 1089 schoolchildren infected). In the southern part of Côte d’Ivoire, the prevalence of S. haematobium was 16.1% with a particularly high prevalence observed in Sikensi (35.6%), while S. mansoni was most prevalent in Agboville (11.2%). Swimming in open freshwater bodies was the main risk factor for S. haematobium infection (adjusted odds ratio (AOR) = 127.0, 95% confidence interval (CI): 25.0–634.0, p < 0.001). Fishing and washing clothes in open freshwater bodies were positively associated with S. haematobium and S. mansoni infection, respectively. Preventive chemotherapy using praziquantel should be combined with setting-specific information, education, and communication strategies in order to change children’s behavior, thus avoiding contact with unprotected open freshwater. Full article
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Open AccessArticle
Community Participation in and Perception of Community-Directed Treatment with Ivermectin in Kinshasa, DRC
Trop. Med. Infect. Dis. 2019, 4(3), 109; https://doi.org/10.3390/tropicalmed4030109 - 19 Jul 2019
Viewed by 516
Abstract
The success of community-directed treatment with Ivermectin (CDTI) depends on active community participation. We conducted a case study nested in a cross-sectional study in the Binza Ozone Health Zone (ZS) in Kinshasa, Democratic Republic of Congo, in order to investigate community’s knowledges and [...] Read more.
The success of community-directed treatment with Ivermectin (CDTI) depends on active community participation. We conducted a case study nested in a cross-sectional study in the Binza Ozone Health Zone (ZS) in Kinshasa, Democratic Republic of Congo, in order to investigate community’s knowledges and perceptions of onchocerciasis and on all CDTI’s aspects. We interviewed 106 people aged 20 and over, purposively selected, through eight individual interviews and 12 focus groups. Themes used for collecting data were drawn for the Health Belief Model and data were analyzed using a deductive thematic approach. The term onchocerciasis was unknown to participants who called it “Mbitiri”, the little black fly, in their local language. This disease is seen as curse put on the sufferer by a witch and perceived as a threat because of the “Mbitiri” bites. The afflicted participants were reluctant to seek treatment and preferred traditional practitioners or healers. CDTI is considered devastating because of adverse effects of ivermectin as well as inefficient after occurrence of deaths. This explains the low level of community adhesion and participation to this strategy. Recruitment procedures for community distributors are poorly understood and awareness and health education campaigns are either non-existent or rarely carried out. Nevertheless, the latter should be regularly done. Full article
Open AccessReview
Advances in Antiwolbachial Drug Discovery for Treatment of Parasitic Filarial Worm Infections
Trop. Med. Infect. Dis. 2019, 4(3), 108; https://doi.org/10.3390/tropicalmed4030108 - 18 Jul 2019
Viewed by 588
Abstract
The intracellular bacteria now known as Wolbachia were first described in filarial worms in the 1970s, but the idea of Wolbachia being used as a macrofilaricidal target did not gain wide attention until the early 2000s, with research in filariae suggesting the requirement [...] Read more.
The intracellular bacteria now known as Wolbachia were first described in filarial worms in the 1970s, but the idea of Wolbachia being used as a macrofilaricidal target did not gain wide attention until the early 2000s, with research in filariae suggesting the requirement of worms for the endosymbiont. This new-found interest prompted the eventual organization of the Anti-Wolbachia Consortium (A-WOL) at the Liverpool School of Tropical Medicine, who, among others have been active in the field of antiwolbachial drug discovery to treat filarial infections. Clinical proof of concept studies using doxycycline demonstrated the utility of the antiwolbachial therapy, but efficacious treatments were of long duration and not safe for all infected. With the advance of robotics, automation, and high-speed computing, the search for superior antiwolbachials shifted away from smaller studies with a select number of antibiotics to high-throughput screening approaches, centered largely around cell-based phenotypic screens due to the rather limited knowledge about, and tools available to manipulate, this bacterium. A concomitant effort was put towards developing validation approaches and in vivo models supporting drug discovery efforts. In this review, we summarize the strategies behind and outcomes of recent large phenotypic screens published within the last 5 years, hit compound validation approaches and promising candidates with profiles superior to doxycycline, including ones positioned to advance into clinical trials for treatment of filarial worm infections. Full article
(This article belongs to the Special Issue Drug Discovery and Development for Tropical Diseases)
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Open AccessCommunication
Training for Tuberculosis Elimination in Indonesia: Achievements, Reflections, and Potential for Impact
Trop. Med. Infect. Dis. 2019, 4(3), 107; https://doi.org/10.3390/tropicalmed4030107 - 18 Jul 2019
Viewed by 539
Abstract
Indonesia has the third highest tuberculosis (TB) caseload internationally. A cornerstone for strengthening health systems to respond to TB is a well-trained workforce. In a partnership between Indonesian and Australian institutions, TB training was run during 2018 to strengthen the local capacity to [...] Read more.
Indonesia has the third highest tuberculosis (TB) caseload internationally. A cornerstone for strengthening health systems to respond to TB is a well-trained workforce. In a partnership between Indonesian and Australian institutions, TB training was run during 2018 to strengthen the local capacity to meet End TB strategy targets. This paper aims to report on course design, delivery, training outcomes, and reflections. Seventy-six Indonesian healthcare workers, program staff, researchers, and policy-makers were selected from over 800 applicants. The structure comprised three trainings, each with a pre-course workshop (in Indonesia) to identify learning needs, a two-week block (Australia), and a post-course workshop (Indonesia). The training content delivered was a combination of TB technical knowledge and program/project theory, design, and logic, and the training utilised multiple teaching and learning methods. An innovative element of the training was participant-designed TB workplace projects focusing on context-specific priorities. Evaluation was undertaken using participant surveys and appraisal of the projects. Participants rated the course highly, while success in project implementation varied. Reflections include the importance of involving Indonesian experts in delivery of training, the need to understand participant learning requirements and adapt the training content accordingly, and the challenge of measuring tangible training outputs. Full article
(This article belongs to the Special Issue Tuberculosis Elimination in the Asia-Pacific)
Open AccessReview
Ternidens deminutus Revisited: A Review of Human Infections with the False Hookworm
Trop. Med. Infect. Dis. 2019, 4(3), 106; https://doi.org/10.3390/tropicalmed4030106 - 18 Jul 2019
Viewed by 553
Abstract
Ternidens deminutus, the false hookworm of humans and non-human primates, represents a truly neglected intestinal helminth infection. The similarity of the eggs of this nematode to those of hookworm both presents a diagnostic challenge and a potential confounder in prevalence surveys of [...] Read more.
Ternidens deminutus, the false hookworm of humans and non-human primates, represents a truly neglected intestinal helminth infection. The similarity of the eggs of this nematode to those of hookworm both presents a diagnostic challenge and a potential confounder in prevalence surveys of soil transmitted helminths (STH) in regions where T. deminutus is found. The helminth infects non-human primates throughout Africa and Asia, but reports of human infection are almost exclusively found in eastern and southern Africa. Historically, an infection prevalence up to 87% has been reported from some parts of Zimbabwe. Scarce reports of ternidensiasis have also been made in individuals in Suriname and one from Thailand. Little work has been performed on this parasite since the 1970s and it not known why human infection has not been reported more widely or what the current prevalence in humans from historically endemic areas is. This review serves to revisit this enigmatic parasite and provide detail to a modern audience of parasitologists on its history, clinical presentation, geographic distribution, life cycle, biology, morphology, diagnosis and treatment. Full article
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Open AccessArticle
Do Communities Really “Direct” in Community-Directed Interventions? A Qualitative Assessment of Beneficiaries’ Perceptions at 20 Years of Community Directed Treatment with Ivermectin in Cameroon
Trop. Med. Infect. Dis. 2019, 4(3), 105; https://doi.org/10.3390/tropicalmed4030105 - 15 Jul 2019
Viewed by 546
Abstract
Recent studies in Cameroon after 20 years of implementation of the Community Directed Treatment with ivermectin (CDTI) strategy, revealed mixed results as regards community ownership. This brings into question the feasibility of Community Directed Interventions (CDI) in the country. We carried out qualitative [...] Read more.
Recent studies in Cameroon after 20 years of implementation of the Community Directed Treatment with ivermectin (CDTI) strategy, revealed mixed results as regards community ownership. This brings into question the feasibility of Community Directed Interventions (CDI) in the country. We carried out qualitative surveys in 3 health districts of Cameroon, consisting of 11 individual interviews and 10 Focus Group Discussions (FGDs) with specific community members. The main topic discussed during individual interviews and FGDs was about community participation in health. We found an implementation gap in CDTI between the process theory in the 3 health districts. Despite this gap, community eagerness for health information and massive personal and financial adhesion to interventions that were perceived important, were indicators of CDI feasibility. The concept of CDI is culturally feasible in rural and semi-urban settlements, but many challenges hinder its actual implementation. In the view of community participation as a process rather than an intervention, these challenges include real dialogue with communities as partners, dialogue and advocacy with operational level health staff, and macroeconomic and political reforms in health, finance and other associated sectors. Full article
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Open AccessReview
Zika Vaccine Development—Current Progress and Challenges for the Future
Trop. Med. Infect. Dis. 2019, 4(3), 104; https://doi.org/10.3390/tropicalmed4030104 - 14 Jul 2019
Viewed by 833
Abstract
Zika virus is an emergent pathogen that gained significant importance during the epidemic in South and Central America as unusual and alarming complications of infection were recognized. Although initially considered a self-limited benign infection, a panoply of neurologic complications were recognized including a [...] Read more.
Zika virus is an emergent pathogen that gained significant importance during the epidemic in South and Central America as unusual and alarming complications of infection were recognized. Although initially considered a self-limited benign infection, a panoply of neurologic complications were recognized including a Guillain–Barré-like syndrome and in-utero fetal infection causing microcephaly, blindness, and other congenital neurologic complications. Numerous Zika virus vaccines were developed, with nine different vaccines representing five different platforms entered into clinical trials, one progressing to Phase II. Here we review the current landscape and challenges confronting Zika virus vaccine development. Full article
(This article belongs to the Special Issue Developing Zika Vaccines: Status Update)
Open AccessPerspective
Marine Microbiome as a Source of Antimalarials
Trop. Med. Infect. Dis. 2019, 4(3), 103; https://doi.org/10.3390/tropicalmed4030103 - 13 Jul 2019
Viewed by 527
Abstract
It is important to discover novel antimalarial pharmacophores because of the widespread emergence of Plasmodium falciparum isolates resistant to the available drugs. Secondary metabolites derived from microbes associated with marine invertebrates are a valuable resource for the discovery of novel drug leads. However, [...] Read more.
It is important to discover novel antimalarial pharmacophores because of the widespread emergence of Plasmodium falciparum isolates resistant to the available drugs. Secondary metabolites derived from microbes associated with marine invertebrates are a valuable resource for the discovery of novel drug leads. However, the potential of marine microbes as a source of antimalarials has not been explored. We investigated the promise of marine microorganisms for the production of antimalarial activities by testing 2365 diverse microbial extracts using phenotypic screening of a multidrug resistant chloroquine resistant P. falciparum strain. We conducted counter screening against mammalian cells for the 317 active extracts that exhibited more than 70% inhibition at 1 µg/mL. The screen identified 17 potent bioactive leads from a broad range of taxa. Our results establish that the marine microbiome is a rich source of antiplasmodial compounds that warrants in depth exploration. Full article
(This article belongs to the Special Issue Drug Discovery and Development for Tropical Diseases)
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Open AccessArticle
Depressive Symptoms Amongst People with Podoconiosis and Lower Limb Lymphoedema of Other Cause in Cameroon: A Cross-Sectional Study
Trop. Med. Infect. Dis. 2019, 4(3), 102; https://doi.org/10.3390/tropicalmed4030102 - 09 Jul 2019
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Abstract
Evidence is emerging that shows elevated mental distress and disorder amongst people with several neglected tropical diseases (NTDs). This study aimed to establish the prevalence of depressive symptoms amongst people with podoconiosis and lower limb lymphoedema of other cause in Cameroon. The study [...] Read more.
Evidence is emerging that shows elevated mental distress and disorder amongst people with several neglected tropical diseases (NTDs). This study aimed to establish the prevalence of depressive symptoms amongst people with podoconiosis and lower limb lymphoedema of other cause in Cameroon. The study was part of a larger research piece that mapped the geographical distribution of podoconiosis in Cameroon. The Patient Health Questionnaire (PHQ-9; mean) was employed to determine the prevalence of depressive symptoms amongst people with lower limb lymphoedema. Linear regression was used to assess the association between socio-demographic characteristics of participants and depressive symptoms. Internal consistency of the PHQ-9 was estimated through Cronbach’s alpha (α = 0.651). The mean PHQ-9 score among people with lower limb lymphoedema was 3.48 (SD ± 3.25). Using a PHQ-9 score of 5 or above as the cut-off score, 32 participants (38.6%) displayed at least mild depressive symptoms. Unemployment was the only factor that was significantly associated with more depressive symptoms overall. This study shows that depressive symptoms are common amongst people with lower limb lymphoedema in Cameroon. The findings provide support for the integration of psychosocial interventions into packages of care for the management of lower limb lymphoedema. Full article
Open AccessArticle
Intercepted Mosquitoes at New Zealand’s Ports of Entry, 2001 to 2018: Current Status and Future Concerns
Trop. Med. Infect. Dis. 2019, 4(3), 101; https://doi.org/10.3390/tropicalmed4030101 - 05 Jul 2019
Viewed by 613
Abstract
Mosquito vectors are extending their range via international travel and trade. Climate change makes New Zealand an increasingly suitable environment for less tropically adapted exotic mosquito vectors to become established. This shift will add a multiplier effect to existing risks of both the [...] Read more.
Mosquito vectors are extending their range via international travel and trade. Climate change makes New Zealand an increasingly suitable environment for less tropically adapted exotic mosquito vectors to become established. This shift will add a multiplier effect to existing risks of both the establishment of new species and of resident exotic species extending into new areas. We describe trends in the border interceptions of exotic mosquitoes and evaluate the role of imported goods as a pathway for these introductions. Ae. aegypti and Ae. albopictus, the two most commonly intercepted species, were only intercepted in Auckland. Used tyres and machinery were the main mode of entry for both species. The majority of Ae. albopictus were transported as larvae by sea, while most Ae. aegypti were transported as adults by air. Continuing introductions of these mosquitoes, mainly arriving via Japan or Australia, increase the risk of the local transmission of mosquito-borne diseases in New Zealand in general and in the Auckland region in particular. These findings reinforce the need for a high performing and adequately resourced national biosecurity system, particularly port surveillance and inspection. Recommended biosecurity improvements are described. Full article
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Open AccessArticle
Delays in Patient Presentation and Diagnosis for Buruli Ulcer (Mycobacterium ulcerans Infection) in Victoria, Australia, 2011–2017
Trop. Med. Infect. Dis. 2019, 4(3), 100; https://doi.org/10.3390/tropicalmed4030100 - 04 Jul 2019
Viewed by 667
Abstract
Uncertainty regarding transmission pathways and control measures makes prompt presentation and diagnosis for Buruli ulcer critical. To examine presentation and diagnosis delays in Victoria, Australia, we conducted a retrospective study of 703 cases notified between 2011 and 2017, classified as residing in an [...] Read more.
Uncertainty regarding transmission pathways and control measures makes prompt presentation and diagnosis for Buruli ulcer critical. To examine presentation and diagnosis delays in Victoria, Australia, we conducted a retrospective study of 703 cases notified between 2011 and 2017, classified as residing in an endemic (Mornington Peninsula; Bellarine Peninsula; South-east Bayside and Frankston) or non-endemic area. Overall median presentation delay was 30 days (IQR 14–60 days), with no significant change over the study period (p = 0.11). There were significant differences in median presentation delay between areas of residence (p = 0.02), but no significant change over the study period within any area. Overall median diagnosis delay was 10 days (IQR 0–40 days), with no significant change over the study period (p = 0.13). There were significant differences in median diagnosis delay between areas (p < 0.001), but a significant decrease over time only on the Mornington Peninsula (p < 0.001). On multivariable analysis, being aged <15 or >65 years; having non-ulcerative disease; and residing in the Bellarine Peninsula or South-East Bayside (compared to non-endemic areas) were significantly associated with shorter presentation delay. Residing in the Bellarine or Mornington Peninsula and being notified later in the study period were significantly associated with shorter diagnosis delay. To reduce presentation and diagnosis delays, awareness of Buruli ulcer must be raised with the public and medical professionals, particularly those based outside established endemic areas. Full article
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Open AccessArticle
Paramyxo- and Coronaviruses in Rwandan Bats
Trop. Med. Infect. Dis. 2019, 4(3), 99; https://doi.org/10.3390/tropicalmed4030099 - 02 Jul 2019
Viewed by 764
Abstract
A high diversity of corona- and paramyxoviruses have been detected in different bat species at study sites worldwide, including Africa, however no biosurveillance studies from Rwanda have been reported. In this study, samples from bats collected from caves in Ruhengeri, Rwanda, were tested [...] Read more.
A high diversity of corona- and paramyxoviruses have been detected in different bat species at study sites worldwide, including Africa, however no biosurveillance studies from Rwanda have been reported. In this study, samples from bats collected from caves in Ruhengeri, Rwanda, were tested for the presence of corona- and paramyxoviral RNA using reverse transcription PCR assays. Positive results were further characterized by DNA sequencing and phylogenetic analysis. In addition to morphological identification of bat species, we also did molecular confirmation of species identities, contributing to the known genetic database available for African bat species. We detected a novel Betacoronavirus in two Geoffroy’s horseshoe bats (Rhinolophus clivosus) bats. We also detected several different paramyxoviral species from various insectivorous bats. One of these viral species was found to be homologous to the genomes of viruses belonging to the Jeilongvirus genus. Additionally, a Henipavirus-related sequence was detected in an Egyptian rousette fruit bat (Rousettus aegyptiacus). These results expand on the known diversity of corona- and paramyxoviruses and their geographical distribution in Africa. Full article
(This article belongs to the Special Issue Emerging Tropical Pathogens of Bats)
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Open AccessArticle
(+)-Spectaline and Iso-6-Spectaline Induce a Possible Cross-Talk between Autophagy and Apoptosis in Trypanosoma brucei rhodesiense
Trop. Med. Infect. Dis. 2019, 4(3), 98; https://doi.org/10.3390/tropicalmed4030098 - 01 Jul 2019
Viewed by 525
Abstract
In our previous study, two known piperidine alkaloids (+)-spectaline (1) and iso-6-spectaline (2) were isolated from the leaves of Senna spectabilis and showed no toxic effect on L6 cells. In view of the potential use of piperidine alkaloids in [...] Read more.
In our previous study, two known piperidine alkaloids (+)-spectaline (1) and iso-6-spectaline (2) were isolated from the leaves of Senna spectabilis and showed no toxic effect on L6 cells. In view of the potential use of piperidine alkaloids in S. spectabilis for the treatment of sleeping sickness, further investigation on the cell death actions of the parasite after treatment with compound 1 and 2 suggested that the treated parasites died by a process of autophagy based on the characteristic morphological alterations observed in intracellular T. b. rhodesiense. In search for apoptosis, interestingly, trypanosomes treated with high concentration of compound 1 and 2 after 72 h significantly induced an early apoptosis-like programmed cell death (PCD) such as phosphatidylserine (PS) exposure, loss of mitochondrial membrane potential and caspases activation. No DNA laddering discriminated late apoptosis event. Taken together, these findings demonstrated the potential of compound 1 and 2 as a natural chemotherapeutic capable of inducing a possible cross-talk between autophagy and apoptosis in T. b. rhodesiense. Full article
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Open AccessReview
Immunological Assays used to Support Efficacy of Zika Virus Vaccines
Trop. Med. Infect. Dis. 2019, 4(3), 97; https://doi.org/10.3390/tropicalmed4030097 - 28 Jun 2019
Viewed by 631
Abstract
In February of 2016, the World Health Organization (WHO) declared Zika virus (ZIKV) a Public Health Emergency of International Concern. This prompted a rapid response from both the private and public sector resulting in the generation of several promising vaccine candidates. In this [...] Read more.
In February of 2016, the World Health Organization (WHO) declared Zika virus (ZIKV) a Public Health Emergency of International Concern. This prompted a rapid response from both the private and public sector resulting in the generation of several promising vaccine candidates. In this review, we discuss published scientific efforts associated with these novel vaccines, emphasizing the immunological assays used to evaluate their immunogenicity and efficacy, and support future licensure. Full article
(This article belongs to the Special Issue Developing Zika Vaccines: Status Update)
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