scholarly journals Free-ranging pigs identified as a multi-reservoir of Trypanosoma brucei and Trypanosoma congolense in the Vavoua area, a historical sleeping sickness focus of Côte d’Ivoire

2021 ◽  
Vol 15 (12) ◽  
pp. e0010036
Author(s):  
Barkissa Mélika Traoré ◽  
Mathurin Koffi ◽  
Martial Kassi N’Djetchi ◽  
Dramane Kaba ◽  
Jacques Kaboré ◽  
...  
Keyword(s):  
Trypanosoma Brucei ◽  
Direct Detection ◽  
Buffy Coat ◽  
World Health ◽  
Animal Reservoir ◽  
Animal Blood ◽  
Different Strains ◽  
Health Organization ◽  
Species Specific ◽  
Free Ranging

Background The existence of an animal reservoir of Trypanosoma brucei gambiense (T. b. gambiense), the agent of human African trypanosomiasis (HAT), may compromise the interruption of transmission targeted by World Health Organization. The aim of this study was to investigate the presence of trypanosomes in pigs and people in the Vavoua HAT historical focus where cases were still diagnosed in the early 2010’s. Methods For the human survey, we used the CATT, mini-anion exchange centrifugation technique and immune trypanolysis tests. For the animal survey, the buffy coat technique was also used as well as the PCR using Trypanosoma species specific, including the T. b. gambiense TgsGP detection using single round and nested PCRs, performed from animal blood samples and from strains isolated from subjects positive for parasitological investigations. Results No HAT cases were detected among 345 people tested. A total of 167 pigs were investigated. Free-ranging pigs appeared significantly more infected than pigs in pen. Over 70% of free-ranging pigs were positive for CATT and parasitological investigations and 27–43% were positive to trypanolysis depending on the antigen used. T. brucei was the most prevalent species (57%) followed by T. congolense (24%). Blood sample extracted DNA of T. brucei positive subjects were negative to single round TgsGP PCR. However, 1/22 and 6/22 isolated strains were positive with single round and nested TgsGP PCRs, respectively. Discussion Free-ranging pigs were identified as a multi-reservoir of T. brucei and/or T. congolense with mixed infections of different strains. This trypanosome diversity hinders the easy and direct detection of T. b. gambiense. We highlight the lack of tools to prove or exclude with certainty the presence of T. b. gambiense. This study once more highlights the need of technical improvements to explore the role of animals in the epidemiology of HAT.

scholarly journals Investigating host-bacterial interactions among enteric pathogens

BMC Genomics ◽  
2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Tungadri Bose ◽  
K. V. Venkatesh ◽  
Sharmila S. Mande
Keyword(s):  
Gut Microbiome ◽  
Therapeutic Strategies ◽  
Enteric Pathogens ◽  
World Health ◽  
Core Set ◽  
Pathogen Protein ◽  
Health Organization ◽  
Species Specific ◽  
Novel Therapeutic Strategies ◽  
Gut Pathogens

Abstract Background In 2017, World Health Organization (WHO) published a catalogue of 12 families of antibiotic-resistant “priority pathogens” that are posing the greatest threats to human health. Six of these dreaded pathogens are known to infect the human gastrointestinal system. In addition to causing gastrointestinal and systemic infections, these pathogens can also affect the composition of other microbes constituting the healthy gut microbiome. Such aberrations in gut microbiome can significantly affect human physiology and immunity. Identifying the virulence mechanisms of these enteric pathogens are likely to help in developing newer therapeutic strategies to counter them. Results Using our previously published in silico approach, we have evaluated (and compared) Host-Pathogen Protein-Protein Interaction (HPI) profiles of four groups of enteric pathogens, namely, different species of Escherichia, Shigella, Salmonella and Vibrio. Results indicate that in spite of genus/ species specific variations, most enteric pathogens possess a common repertoire of HPIs. This core set of HPIs are probably responsible for the survival of these pathogen in the harsh nutrient-limiting environment within the gut. Certain genus/ species specific HPIs were also observed. Conslusions The identified bacterial proteins involved in the core set of HPIs are expected to be helpful in understanding the pathogenesis of these dreaded gut pathogens in greater detail. Possible role of genus/ species specific variations in the HPI profiles in the virulence of these pathogens are also discussed. The obtained results are likely to provide an opportunity for development of novel therapeutic strategies against the most dreaded gut pathogens.

scholarly journals Pediatric Bacterial Meningitis Surveillance in Nigeria From 2010 to 2016, Prior to and During the Phased Introduction of the 10-Valent Pneumococcal Conjugate Vaccine

2019 ◽  
Vol 69 (Supplement_2) ◽  
pp. S81-S88 ◽  
Author(s):  
Beckie N Tagbo ◽  
Rowan E Bancroft ◽  
Iretiola Fajolu ◽  
Mohammed B Abdulkadir ◽  
Muhammad F Bashir ◽  
...  
Keyword(s):  
Bacterial Meningitis ◽  
Conjugate Vaccine ◽  
Pneumococcal Conjugate Vaccine ◽  
Invasive Disease ◽  
Latex Agglutination ◽  
World Health ◽  
Vaccine Introduction ◽  
Vaccine Type ◽  
Health Organization ◽  
Species Specific

Abstract Background Historically, Nigeria has experienced large bacterial meningitis outbreaks with high mortality in children. Streptococcus pneumoniae (pneumococcus), Neisseria meningitidis (meningococcus), and Haemophilus influenzae are major causes of this invasive disease. In collaboration with the World Health Organization, we conducted longitudinal surveillance in sentinel hospitals within Nigeria to establish the burden of pediatric bacterial meningitis (PBM). Methods From 2010 to 2016, cerebrospinal fluid was collected from children <5 years of age, admitted to 5 sentinel hospitals in 5 Nigerian states. Microbiological and latex agglutination techniques were performed to detect the presence of pneumococcus, meningococcus, and H. influenzae. Species-specific polymerase chain reaction and serotyping/grouping were conducted to determine specific causative agents of PBM. Results A total of 5134 children with suspected meningitis were enrolled at the participating hospitals; of these 153 (2.9%) were confirmed PBM cases. The mortality rate for those infected was 15.0% (23/153). The dominant pathogen was pneumococcus (46.4%: 71/153) followed by meningococcus (34.6%: 53/153) and H. influenzae (19.0%: 29/153). Nearly half the pneumococcal meningitis cases successfully serotyped (46.4%: 13/28) were caused by serotypes that are included in the 10-valent pneumococcal conjugate vaccine. The most prevalent meningococcal and H. influenzae strains were serogroup W and serotype b, respectively. Conclusions Vaccine-type bacterial meningitis continues to be common among children <5 years in Nigeria. Challenges with vaccine introduction and coverage may explain some of these finding. Continued surveillance is needed to determine the distribution of serotypes/groups of meningeal pathogens across Nigeria and help inform and sustain vaccination policies in the country.

scholarly journals Accelerating Drug Discovery Efforts for Trypanosomatidic Infections Using an Integrated Transnational Academic Drug Discovery Platform

2019 ◽  
Vol 24 (3) ◽  
pp. 346-361 ◽  
Author(s):  
Carolina B. Moraes ◽  
Gesa Witt ◽  
Maria Kuzikov ◽  
Bernhard Ellinger ◽  
Theodora Calogeropoulou ◽  
...  
Keyword(s):  
Natural Products ◽  
Drug Discovery ◽  
Trypanosoma Brucei ◽  
Value Chain ◽  
Neglected Tropical Diseases ◽  
World Health ◽  
Synthetic Compound ◽  
Antiparasitic Activity ◽  
Compound Libraries ◽  
Health Organization

According to the World Health Organization, more than 1 billion people are at risk of or are affected by neglected tropical diseases. Examples of such diseases include trypanosomiasis, which causes sleeping sickness; leishmaniasis; and Chagas disease, all of which are prevalent in Africa, South America, and India. Our aim within the New Medicines for Trypanosomatidic Infections project was to use (1) synthetic and natural product libraries, (2) screening, and (3) a preclinical absorption, distribution, metabolism, and excretion–toxicity (ADME-Tox) profiling platform to identify compounds that can enter the trypanosomatidic drug discovery value chain. The synthetic compound libraries originated from multiple scaffolds with known antiparasitic activity and natural products from the Hypha Discovery MycoDiverse natural products library. Our focus was first to employ target-based screening to identify inhibitors of the protozoan Trypanosoma brucei pteridine reductase 1 ( TbPTR1) and second to use a Trypanosoma brucei phenotypic assay that made use of the T. brucei brucei parasite to identify compounds that inhibited cell growth and caused death. Some of the compounds underwent structure-activity relationship expansion and, when appropriate, were evaluated in a preclinical ADME-Tox assay panel. This preclinical platform has led to the identification of lead-like compounds as well as validated hits in the trypanosomatidic drug discovery value chain.

scholarly journals A Strategy for Efficient Preparation of Genus-Specific Diagnostic Antibodies for Snakebites

2021 ◽  
Vol 12 ◽  
Author(s):  
Chengbo Long ◽  
Feilong Wu ◽  
Qiumin Lu ◽  
Bing Xie ◽  
Chuanbin Shen ◽  
...  
Keyword(s):  
Snake Venom ◽  
Sandwich Elisa ◽  
Diagnostic Methods ◽  
Tropical Disease ◽  
Spatial Accessibility ◽  
World Health ◽  
Peptide Fragments ◽  
Snake Venoms ◽  
Health Organization ◽  
Species Specific

As said by former United Nations Secretary-General Kofi Annan, “Snakebite is the most important tropical disease you’ve never heard of.” Listed as a priority neglected tropical disease by the World Health Organization, snakebite envenoming (SBE) kills in excess of 125,000 people per year. However, due to the complexity and overlap of snake venom compositions, few reliable venom diagnostic methods for genus-/species-specific identification, which is crucial for successful SBE therapy, are available. Here, we develop a strategy to select and prepare genus-specific snake venom antibodies, which allows rapid and efficient clinical diagnosis of snakebite. Multi-omics approaches are used to choose candidate antigens from snake venoms and identify genus-specific antigenic epitope peptide fragments (GSAEPs) with ideal immunogenicity, specificity, and spatial accessibility. Double-antibody sandwich ELISA kit was established by matching a polyclonal antibody against a natural antigen and a monoclonal antibody that was prepared by natural protein as antigen and can specifically target the GSAEPs. The kit shows the ability to accurately identify venoms from similar genera of Trimeresurus and Protobothrops with a detection limit of 6.25 ng/ml on the snake venoms and a little cross-reaction, thus proving high feasibility and applicability.

Severe Acute Respiratory Syndrome (SARS)

2011 ◽  
Author(s):  
Merion Evans ◽  
Diana J. Bell
Keyword(s):  
Severe Acute Respiratory Syndrome ◽  
Southern China ◽  
Rapid Identification ◽  
World Health ◽  
Wildlife Trade ◽  
Animal Reservoir ◽  
Treatment Protocols ◽  
Factors Affecting ◽  
Horseshoe Bat ◽  
Health Organization

Severe acute respiratory syndrome (SARS) has been described by the World Health Organization (WHO) as the first serious and readily transmissible disease to emerge in the 21st century (WHO 2003a). The epidemic first appeared in southern China in late 2002 and was finally contained in July 2003 after spreading to 29 countries worldwide and infecting over 8,000 people with 774 reported deaths. The last known cases occurred in April 2004 after a laboratory acquired infection in China. The global response to the SARS epidemic, co-ordinated by WHO, led to the rapid identification of the causal agent, the development of diagnostic tests for the virus, the initiation of treatment protocols, estimation of key epidemiological factors affecting spread and the implementation of a range of public health interventions (WHO 2003a; Anderson et al. 2005).The cause of SARS has been conclusively identified as a previously unknown coronavirus (Peiris et al. 2003a; Ksiazek et al. 2003; Drosten et al. 2003). Early reports suggested a wild animal reservoir for the virus and attention focused on the wildlife trade in southern China (Xu et al. 2004). Numerous animal reservoirs of the SARS coronavirus have since been identified (Shi and Hu 2007). Masked palm civets (Paguma larvata) have been most consistently identified as the intermediate host responsible for passing the virus to humans (Guan et al. 2003; Song et al. 2005; Wang et al. 2005), while the definitive hosts may be the horseshoe bat species (genus Rhinolophus) (Wang et al. 2006 ).

First Example of Antiparasitic Activity Influenced by Thermochromism: Leishmanicidal Evaluation of 5,7-dimethyl-1,2,4-triazolo[1,5-a]pyrimidine Metal Complexes

2020 ◽  
Vol 16 (3) ◽  
pp. 422-430 ◽  
Author(s):  
José M. Méndez-Arriaga ◽  
Itziar Oyarzabal ◽  
Álvaro Martín-Montes ◽  
Judith García-Rodríguez ◽  
Miguel Quirós ◽  
...  
Keyword(s):  
Physical Properties ◽  
Metal Complexes ◽  
New Drugs ◽  
Host Cells ◽  
World Health ◽  
Neglected Diseases ◽  
Leishmania Spp ◽  
Different Strains ◽  
Health Organization

Background: The World Health Organization catalogues illnesses such as Leishmaniasis as neglected diseases, due to low investment in new drugs to fight them. The search of novel and non-side effects anti-parasitic compounds is one of the urgent needs for the Third World. The use of triazolopyrimidines and their metallic complexes has demonstrated hopeful results in this field. Objective: This work studies the antiparasitic efficacy of a series of 5,7-dimethyl-1,2,4- triazolo[1,5-a]pyrimidine first row transition metal complexes against three leishmania spp. strains. Methods: The in vitro antiproliferation of promastigote forms of different strains of leishmania spp. (L. infantum, L. braziliensis and L donovani) and the cytotoxicity in macrophage host cells are reported here. The antiparasitic assays have been complemented with enzymatic tests to elucidate the mechanisms of action. New crystal structure description, thermal analysis, magnetic susceptibility and magnetization experiments have also been carried out in order to present a whole characterization of the studied compounds and interesting physical properties besides the biological tests. Results: The results of antiproliferation screening and cytotoxicity show great antiparasitic efficacy in the studied complexes. The superoxide dismutase enzymatic assays exhibit a different behaviour according to the thermochromic triazolopyrimidine form tested. Conclusion: Antiproliferative assays and enzymatic tests corroborate the synergetic leishmanicidal effect present in coordination triazolopyrimidine complexes. The changes in coordination sphere derived from thermochromism affect the physical properties as well as the biological efficacy.

scholarly journals Haemoparasitic Infections in Cattle from a Trypanosoma brucei Rhodesiense Sleeping Sickness Endemic District of Eastern Uganda

2020 ◽  
Vol 5 (1) ◽  
pp. 24
Author(s):  
Enock Matovu ◽  
Claire Mack Mugasa ◽  
Peter Waiswa ◽  
Annah Kitibwa ◽  
Alex Boobo ◽  
...  
Keyword(s):  
Trypanosoma Brucei ◽  
Capillary Tube ◽  
Domestic Animal ◽  
Buffy Coat ◽  
Baseline Survey ◽  
Multiple Infections ◽  
Trypanosoma Brucei Rhodesiense ◽  
Animal Reservoir ◽  
Pcr Targeting ◽  
Eastern Uganda

We carried out a baseline survey of cattle in Kaberamaido district, in the context of controlling the domestic animal reservoir of Trypanosoma brucei rhodesiense human African trypanosomiasis (rHAT) towards elimination. Cattle blood was subjected to capillary tube centrifugation followed by measurement of the packed cell volume (PCV) and examination of the buffy coat area for motile trypanosomes. Trypanosomes were detected in 561 (21.4%) out of 2621 cattle screened by microscopy. These 561 in addition to 724 apparently trypanosome negative samples with low PCVs (≤25%) were transported to the laboratory and tested by PCR targeting the trypanosomal Internal Transcribed Spacer (ITS-1) as well as suspect Tick-Borne Diseases (TBDs) including Anaplasmamosis, Babesiosis, and Theileriosis. PCR for Anaplasma sp yielded the highest number of positive animals (45.2%), followed by Trypanosoma sp (44%), Theileria sp (42.4%) and Babesia (26.3%); multiple infections were a common occurrence. Interestingly, 373 (29%) of these cattle with low PCVs were negative by PCR, pointing to other possible causes of aneamia, such as helminthiasis. Among the trypanosome infections classified as T. brucei by ITS-PCR, 5.5% were positive by SRA PCR, and were, therefore, confirmed as T. b. rhodesiense. Efforts against HAT should therefore consider packages that address a range of conditions. This may enhance acceptability and participation of livestock keepers in programs to eliminate this important but neglected tropical disease. In addition, we demonstrated that cattle remain an eminent reservoir for T. b. rhodesiense in eastern Uganda, which must be addressed to sustain HAT elimination.

scholarly journals DNA barcodes reveal species-specific mercury levels in tuna sushi that pose a health risk to consumers

2010 ◽  
Vol 6 (5) ◽  
pp. 692-695 ◽  
Author(s):  
Jacob H. Lowenstein ◽  
Joanna Burger ◽  
Christian W. Jeitner ◽  
George Amato ◽  
Sergios-Orestis Kolokotronis ◽  
...  
Keyword(s):  
Health Hazard ◽  
World Health ◽  
Dna Barcodes ◽  
The European Union ◽  
Market Place ◽  
Thunnus Orientalis ◽  
Thunnus Obesus ◽  
Predatory Fishes ◽  
Health Organization ◽  
Species Specific

Excessive ingestion of mercury—a health hazard associated with consuming predatory fishes—damages neurological, sensory-motor and cardiovascular functioning. The mercury levels found in Bigeye Tuna ( Thunnus obesus ) and bluefin tuna species ( Thunnus maccoyii , Thunnus orientalis , and Thunnus thynnus ), exceed or approach levels permissible by Canada, the European Union, Japan, the US, and the World Health Organization. We used DNA barcodes to identify tuna sushi samples analysed for mercury and demonstrate that the ability to identify cryptic samples in the market place allows regulatory agencies to more accurately measure the risk faced by fish consumers and enact policies that better safeguard their health.

scholarly journals Whole Cell Recognition of Staphylococcus aureus Using Biomimetic SPR Sensors

Biosensors ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 140
Author(s):  
Neslihan Idil ◽  
Monireh Bakhshpour ◽  
Işık Perçin ◽  
Bo Mattiasson
Keyword(s):  
Staphylococcus Aureus ◽  
Resistance Genes ◽  
Large Scale ◽  
World Health ◽  
Sensor Technology ◽  
Multi Drug Resistance ◽  
Bacterial Strains ◽  
Whole Cell ◽  
Different Strains ◽  
Health Organization

Over the past few decades, a significant increase in multi-drug-resistant pathogenic microorganisms has been of great concern and directed the research subject to the challenges that the distribution of resistance genes represent. Globally, high levels of multi-drug resistance represent a significant health threat and there is a growing requirement of rapid, accurate, real-time detection which plays a key role in tracking of measures for the infections caused by these bacterial strains. It is also important to reduce transfer of resistance genes to new organisms. The, World Health Organization has informed that millions of deaths have been reported each year recently. To detect the resistant organisms traditional detection approaches face limitations, therefore, newly developed technologies are needed that are suitable to be used in large-scale applications. In the present study, the aim was to design a surface plasmon resonance (SPR) sensor with micro-contact imprinted sensor chips for the detection of Staphylococcus aureus. Whole cell imprinting was performed by N-methacryloyl-L-histidine methyl ester (MAH) under UV polymerization. Sensing experiments were done within a concentration range of 1.0 × 102–2.0 × 105 CFU/mL. The recognition of S. aureus was accomplished by the involvement of microcontact imprinting and optical sensor technology with a detection limit of 1.5 × 103 CFU/mL. Selectivity of the generated sensor was evaluated through injections of competing bacterial strains. The responses for the different strains were compared to that of S. aureus. Besides, real experiments were performed with milk samples spiked with S. aureus and it was demonstrated that the prepared sensor platform was applicable for real samples.

scholarly journals Species identification and phylogenetic analysis of Leishmania isolated from patients, vectors and hares in the Xinjiang Autonomous Region, The People’s Republic of China

2021 ◽  
Vol 15 (12) ◽  
pp. e0010055
Author(s):  
Yun-Fu Chen ◽  
Li-Fu Liao ◽  
Na Wu ◽  
Jiang-Mei Gao ◽  
Peng Zhang ◽  
...  
Keyword(s):  
Phylogenetic Analyses ◽  
World Health ◽  
Sand Fly ◽  
Animal Reservoir ◽  
Autonomous Region ◽  
Republic Of China ◽  
Potential Reservoir ◽  
Health Organization ◽  
Xinjiang Autonomous Region ◽  
Sand Fly Vectors

Background Visceral leishmaniasis (VL) has been declared as one of the six major tropical diseases by the World Health Organization. This disease has been successfully controlled in China, except for some areas in the western region, such as the Xinjiang Autonomous Region, where both anthroponotic VL (AVL) and desert type zoonotic VL (DT-ZVL) remain endemic with sporadic epidemics. Methodology/Principal findings Here, an eleven-year survey (2004–2014) of Leishmania species, encompassing both VL types isolated from patients, sand-fly vectors and Tarim hares (Lepus yarkandensis) from the Xinjiang Autonomous Region was conducted, with a special emphasis on the hares as a potential reservoir animal for DT-ZVL. Key diagnostic genes, ITS1, hsp70 and nagt (encoding N-acetylglucosamine-1-phosphate transferase) were used for phylogenetic analyses, placing all Xinjiang isolates into one clade of the L. donovani complex. Unexpectedly, AVL isolates were found to be closely related to L. infantum, while DT-ZVL isolates were closer to L. donovani. Unrooted parsimony networks of haplotypes for these isolates also revealed their relationship. Conclusions/Significance The above analyses of the DT-ZVL isolates suggested their geographic isolation and independent evolution. The sequence identity of isolates from patients, vectors and the Tarim hares in a single DT-ZVL site provides strong evidence in support of this species as an animal reservoir.

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