scholarly journals Trichuris trichiura (Linnaeus, 1771) From Human and Non-human Primates: Morphology, Biometry, Host Specificity, Molecular Characterization, and Phylogeny

2021 ◽  
Vol 7 ◽  
Author(s):  
Julia Rivero ◽  
Cristina Cutillas ◽  
Rocío Callejón

Human trichuriasis is a Neglected Tropical Disease, which affects hundreds of millions of persons worldwide. Several studies have reported that non-human primates (NHP) represent important reservoirs for several known zoonotic infectious diseases. In this context, Trichuris infections have been found in a range of NHP species living in natural habitats, including colobus monkeys, macaques, baboons, and chimpanzees. To date, the systematics of the genus Trichuris parasitizing humans and NHP is unclear. During many years, Trichuris trichiura was considered as the whipworm present in humans and primates. Subsequently, molecular studies suggested that Trichuris spp. in humans and NHP represent several species that differ in host specificity. This work examines the current knowledge of T. trichiura and its relationship to whipworm parasites in other primate host species. A phylogenetic hypothesis, based on three mitochondrial genes (cytochrome c oxidase subunit 1, cytochrome b, and large subunit rRNA-encoding gene) and two fragments of ribosomal DNA (Internal Transcribed Spacer 1 and 2), allowed us to define a complex of populations of T. trichiura hosting in a large variety of NHP species, in addition to humans. These populations were divided into four phylogenetic groups with a different degree of host specificity. From these data, we carry out a new morphological and biometrical description of the populations of Trichuris based on data cited by other authors as well as those provided in this study. The presence of T. trichiura is analyzed in several NHP species in captivity from different garden zoos as possible reservoir of trichuriasis for humans. This study contributes to clarify questions that lead to identification of new taxa and will determine parasite transmission routes between these primates, allowing the implementation of appropriate control and prevention measures.

Biosensors ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 14
Author(s):  
Priya Dave ◽  
Roberto Rojas-Cessa ◽  
Ziqian Dong ◽  
Vatcharapan Umpaichitra

The United States Centers for Disease Control and Prevention considers saliva contact the lead transmission mean of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes the coronavirus disease 2019 (COVID-19). Saliva droplets or aerosols expelled by sneezing, coughing, breathing, and talking may carry this virus. People in close distance may be exposed directly to these droplets or indirectly when touching the droplets that fall on surrounding surfaces and ending up contracting COVID-19 after touching the mucosa tissue of their faces. It is of great interest to quickly and effectively detect the presence of SARS-CoV-2 in an environment, but the existing methods only work in laboratory settings, to the best of our knowledge. However, it may be possible to detect the presence of saliva in the environment and proceed with prevention measures. However, detecting saliva itself has not been documented in the literature. On the other hand, many sensors that detect different organic components in saliva to monitor a person’s health and diagnose different diseases, ranging from diabetes to dental health, have been proposed and they may be used to detect the presence of saliva. This paper surveys sensors that detect organic and inorganic components of human saliva. Humidity sensors are also considered in the detection of saliva because a large portion of saliva is water. Moreover, sensors that detect infectious viruses are also included as they may also be embedded into saliva sensors for a confirmation of the presence of the virus. A classification of sensors by their working principles and the substances they detect is presented, including the sensors’ specifications, sample size, and sensitivity. Indications of which sensors are portable and suitable for field application are presented. This paper also discusses future research and challenges that must be resolved to realize practical saliva sensors. Such sensors may help minimize the spread of not only COVID-19 but also other infectious diseases.


2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Vivian Ntono ◽  
Daniel Eurien ◽  
Lilian Bulage ◽  
Daniel Kadobera ◽  
Julie Harris ◽  
...  

Abstract Background On 18 January 2018 a 40 year old man presented with skin lesions at Rhino Camp Health Centre. A skin lesion swab was collected on 20 January 2018 and was confirmed by PCR at Uganda Virus Research Institute on 21 January 2018. Subsequently, about 9 persons were reported to have fallen ill after reporting contact with livestock that died suddenly. On 9 February 2018, Arua District notified Uganda Ministry of Health of a confirmed anthrax outbreak among humans in Rhino Camp sub-county. We investigated to determine the scope and mode of transmission and exposures associated with identified anthrax to guide control and prevention measures. Methods We defined a suspected cutaneous anthrax case as onset of skin lesions (e.g., papule, vesicle, or eschar) in a person residing in Rhino Camp sub-county, Arua District from 25 December 2017 to 31 May 2018. A confirmed case was a suspected case with PCR-positivity for Bacillus anthracis from a clinical sample. We identified cases by reviewing medical records at Rhino Camp Health Centre. We also conducted additional case searches in the affected community with support from Community Health Workers. In a retrospective cohort study, we interviewed all members of households in which at least one person had contact with the carcasses of or meat from animals suspected to have died of anthrax. We collected and tested hides of implicated animals using an anthrax rapid diagnostic test. Results We identified 14 case-patients (1 confirmed, 13 suspected); none died. Only males were affected (affected proportion: 12/10,000). Mean age of case-persons was 33 years (SD: 22). The outbreak lasted for 5 months, from January 2018–May 2018, peaking in February. Skinning (risk ratio = 2.7, 95% CI = 1.1–6.7), dissecting (RR = 3.0, 95% CI = 1.2–7.6), and carrying dead animals (RR = 2.7, 95% CI = 1.1–6.7) were associated with increased risk of illness, as were carrying dissected parts of animals (RR = 2.9, 95% CI 1.3–6.5) and preparing and cooking the meat (RR = 2.3, 95% CI 0.9–5.9). We found evidence of animal remains on pastureland. Conclusion Multiple exposures to the hides and meat of animals that died suddenly were associated with this cutaneous anthrax outbreak in Arua District. We recommended public education about safe disposal of carcasses of livestock that die suddenly.


Author(s):  
Silvia Di Meo ◽  
Enrico Bentivegna

AbstractThe COVID-19 pandemic represents an important risk factor for migrants’ health. Paul Farmer highlighted the risk of global health response in emergency conditions exacerbating global and social inequalities. We argue that this is the case for quarantine ships and migrants’ management during the pandemic. Every aspect of infection-control and prevention measures acquires detention characteristics in these situations. With emphasis to the evolution of the doctor-patient relationship and to the anthropological and cultural aspects that were established during the pandemic, this article aims to provide an integrated view where physicians and anthropologists collaborate to deepen the understanding of the topic.


2004 ◽  
Vol 54 (5) ◽  
pp. 1891-1894 ◽  
Author(s):  
Solange C. Carreiro ◽  
Fernando C. Pagnocca ◽  
Maurício Bacci ◽  
Marc-André Lachance ◽  
Odair C. Bueno ◽  
...  

Four strains of a novel yeast species were isolated from laboratory nests of the leaf-cutting ant Atta sexdens in Brazil. Three strains were found in older sponges and one was in a waste deposit in the ant nests. Sequencing of the D1/D2 region of the large-subunit rRNA gene showed that the novel species, named Sympodiomyces attinorum sp. nov., is phylogenetically related to Sympodiomyces parvus. Unlike Sympodiomyces parvus, Sympodiomyces attinorum can ferment glucose, assimilate methyl α-d-glucoside, salicin and citrate, and grow at 37 °C, thus enabling these two species to be distinguished. Differentiation from other related species is possible on the basis of other growth characteristics. The type strain of Sympodiomyces attinorum is UNESP-S156T (=CBS 9734T=NRRL Y-27639T).


2018 ◽  
Vol 373 (1740) ◽  
pp. 20160508 ◽  
Author(s):  
Sarah Benson-Amram ◽  
Geoff Gilfillan ◽  
Karen McComb

Playback experiments have proved to be a useful tool to investigate the extent to which wild animals understand numerical concepts and the factors that play into their decisions to respond to different numbers of vocalizing conspecifics. In particular, playback experiments have broadened our understanding of the cognitive abilities of historically understudied species that are challenging to test in the traditional laboratory, such as members of the Order Carnivora. Additionally, playback experiments allow us to assess the importance of numerical information versus other ecologically important variables when animals are making adaptive decisions in their natural habitats. Here, we begin by reviewing what we know about quantity discrimination in carnivores from studies conducted in captivity. We then review a series of playback experiments conducted with wild social carnivores, including African lions, spotted hyenas and wolves, which demonstrate that these animals can assess the number of conspecifics calling and respond based on numerical advantage. We discuss how the wild studies complement those conducted in captivity and allow us to gain insights into why wild animals may not always respond based solely on differences in quantity. We then consider the key roles that individual discrimination and cross-modal recognition play in the ability of animals to assess the number of conspecifics vocalizing nearby. Finally, we explore new directions for future research in this area, highlighting in particular the need for further work on the cognitive basis of numerical assessment skills and experimental paradigms that can be effective in both captive and wild settings. This article is part of a discussion meeting issue ‘The origins of numerical abilities’.


2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Mercia Rasoanoro ◽  
Steven M. Goodman ◽  
Milijaona Randrianarivelojosia ◽  
Mbola Rakotondratsimba ◽  
Koussay Dellagi ◽  
...  

Abstract Background Numerous studies have been undertaken to advance knowledge of apicomplexan parasites infecting vertebrates, including humans. Of these parasites, the genus Plasmodium has been most extensively studied because of the socio-economic and public health impacts of malaria. In non-human vertebrates, studies on malaria or malaria-like parasite groups have been conducted but information is far from complete. In Madagascar, recent studies on bat blood parasites indicate that three chiropteran families (Miniopteridae, Rhinonycteridae, and Vespertilionidae) are infected by the genus Polychromophilus with pronounced host specificity: Miniopterus spp. (Miniopteridae) harbour Polychromophilus melanipherus and Myotis goudoti (Vespertilionidae) is infected by Polychromophilus murinus. However, most of the individuals analysed in previous studies were sampled on the western and central portions of the island. The aims of this study are (1) to add new information on bat blood parasites in eastern Madagascar, and (2) to highlight biotic and abiotic variables driving prevalence across the island. Methods Fieldworks were undertaken from 2014 to 2016 in four sites in the eastern portion of Madagascar to capture bats and collect biological samples. Morphological and molecular techniques were used to identify the presence of haemosporidian parasites. Further, a MaxEnt modelling was undertaken using data from Polychromophilus melanipherus to identify variables influencing the presence of this parasite Results In total, 222 individual bats belonging to 17 species and seven families were analysed. Polychromophilus infections were identified in two families: Miniopteridae and Vespertilionidae. Molecular data showed that Polychromophilus spp. parasitizing Malagasy bats form a monophyletic group composed of three distinct clades displaying marked host specificity. In addition to P. melanipherus and P. murinus, hosted by Miniopterus spp. and Myotis goudoti, respectively, a novel Polychromophilus lineage was identified from a single individual of Scotophilus robustus. Based on the present study and the literature, different biotic and abiotic factors are shown to influence Polychromophilus infection in bats, which are correlated based on MaxEnt modelling. Conclusions The present study improves current knowledge on Polychromophilus blood parasites infecting Malagasy bats and confirms the existence of a novel Polychromophilus lineage in Scotophilus bats. Additional studies are needed to obtain additional material of this novel lineage to resolve its taxonomic relationship with known members of the genus. Further, the transmission mode of Polychromophilus in bats as well as its potential effect on bat populations should be investigated to complement the results provided by MaxEnt modelling and eventually provide a comprehensive picture of the biology of host-parasite interactions.


2021 ◽  
Author(s):  
Sophia Kindzierski ◽  
Welmoed van Loon ◽  
Johanna Theuring ◽  
Franziska Hommes ◽  
Eberhard Thombansen ◽  
...  

SARS-CoV-2 infections in childcare and school settings potentially bear occupational risks to educational staff. We analyzed data derived from voluntary, PCR-based screening of childcare educators and teachers attending five testing sites in Berlin, Germany, between June and December 2020. Within seven months, 17,491 tests were performed (4,458 educators, 13,033 teachers). Participants were largely female (72.9%), and median age was 41 years. Overall, SARS-CoV-2 infection prevalence was 1.2% (95%CI, 1.1-1.4%). Prevalence in educational staff largely resembled community incidence until the start of the second pandemic wave in mid-September 2020, when an unsteady prevalence plateau was reached. Then, infection prevalence in teachers (1.2% [95%CI, 0.8-1.8%]) did not significantly differ from the population prevalence (0.9% [0.6-1.4%]) but it was increased in educators (2.6% [1.6-4.0%]; aOR, 1.6 [1.3-2.0]). Irrespective of occupation, those that reported contact to a confirmed SARS-CoV-2 case outside of work had increased risk of infection (aOR, 3.0 [95%CI, 1.5-5.5]). In a step-wise backwards selection, the best set of associated factors with SARS-CoV-2 infection involved age, occupation, and calendar week. These results are in line with findings that teachers do not bear an increased risk of SARS-CoV-2 infection, while childcare educators do. Infection control and prevention measures need to be strengthened in child care settings to further reduce respective occupational hazards. At the same time, the private environment appears to be the main source of SARS-CoV-2 infection for educational staff.


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