Transmission Of Pathogenic Agents Research Articles

IETS management of the challenges associated with embryo pathogen interaction

One of the very first challenges the International Embryo Transfer Society (IETS) addressed was concern about disease transmission via the transfer of in vivo–derived (IVD) bovine embryos. IETS commissioned its Import/Export Committee, later named Health and Safety Advisory Committee (HASAC), to resolve this matter, with the assistance of the Data Retrieval Committee following its formation in 1991. Since its first meeting in 1984, considerable achievements have been made, including meeting the numerous challenges created by the many innovations in this industry. Based on research studies and their designs, the IETS HASAC developed a system for categorising pathogens and diseases potentially susceptible to interaction with IVD embryos. This has been instrumental in defining safe operating protocols and ultimately leading to the development of the now universally accepted techniques for certification of embryo health. The close cooperation of IETS/HASAC with the World Organization of Animal Health (WOAH, formerly OIE) has facilitated the establishment of guidelines for regulators worldwide, thus ensuring the safety of international trade with embryos, while avoiding unjustified regulatory measures. In addition, IETS/HASAC produced and published the IETS Manual: A Procedural Guide and General Information for the Use of Embryo Transfer Technology Emphasising Sanitary Procedures for the embryo transfer industry (1st edition, 1987; 5th edition, 2023). This manual and its updates were designed to provide the industry world-wide with a source of information on safe and sanitary handling procedures for embryos, to describe the procedures necessary to ensure that the transfer of embryos does not result in transmission of pathogenic agents or disease, and to ensure consistent and accurate identification of embryos. The result of these 40 years of IETS/HASAC involvement is that embryo transfer technology is recognised as having a comparative advantage in international movement of germplasm.

Investigation of Cryptosporidium spp. in breeding nucleus of capuchin monkeys (Sapajus spp.)

Animals of the primate order are highly susceptible to parasitic infections due to their social organization, often in groups and interaction between individuals, facilitating the transmission of pathogenic agents, and may be even more prevalent in areas modified by anthropic action. The occurrence of the protozoan Cryptosporidium spp. in wildlife animals in captivity or free-living it characterizes great importance of Public Health mainly for its zoonotic potential. This parasite has a cosmopolitan distribution, causes gastrointestinal infection, and its transmission occurs via the fecal-oral route, either through water or through contaminated food. Cryptosporidiosis affects mammals, birds, reptiles and fish, this significant zoonotic potential, in addition to being directly related to the living conditions of the host and the quality of the environment. We investigated the occurrence of Cryptosporidium spp. in primates located at the Tufted Capuchin Monkey Procreation Center (School of Dentistry of Araçatuba - UNESP). Fecal samples from 49 asymptomatic primates of the species Sapajus spp. species were collected below their individual cages, the soil was lined with a plastic bag, thus hindering environmental contamination. The search for oocysts was carried out using the technique of Negative Malachite Green Staining, finding negativity in all samples examined, which suggests the absence of the protozoan Cryptosporidium spp. in primates studied in the breeding center of capuchin monkeys (Sapajus spp.), noting that they were asymptomatic.

Microorganisms Associated with Mosquito Oviposition Sites: Implications for Habitat Selection and Insect Life Histories.

Mosquitoes are considered one of the most important threats worldwide due to their ability to vector pathogens. They are responsible for the transmission of major pathogens such as malaria, dengue, zika, or chikungunya. Due to the lack of treatments or prophylaxis against many of the transmitted pathogens and an increasing prevalence of mosquito resistance to insecticides and drugs available, alternative strategies are now being explored. Some of these involve the use of microorganisms as promising agent to limit the fitness of mosquitoes, attract or repel them, and decrease the replication and transmission of pathogenic agents. In recent years, the importance of microorganisms colonizing the habitat of mosquitoes has particularly been investigated since they appeared to play major roles in their development and diseases transmission. In this issue, we will synthesize researches investigating how microorganisms present within water habitats may influence breeding site selection and oviposition strategies of gravid mosquito females. We will also highlight the impact of such microbes on the fate of females’ progeny during their immature stages with a specific focus on egg hatching, development rate, and larvae or pupae survival.

Beyond taxonomy: species complexes in New World phlebotomine sand flies.

A species complex (= species group, species series) is an assemblage of species, which are related morphologically and phylogenetically. Recent research has revealed several arthropod vector species that were believed to be a single nominal species actually representing a group of closely related species, which are sometimes morphologically indistinguishable at one or more developmental stages. In some instances, differences in terms of vector competence, capacity, or both have been recorded. It highlights the importance of detecting and studying species complexes to improve our understanding of pathogen transmission patterns, which may be vectored more or less efficiently by different species within the complex. Considering more than 540 species, about one-third of the phlebotomine sand flies in the New World present males and/or females morphologically indistinguishable to one or more species. Remarkably, several of these species may act in transmission of pathogenic agents. In this article, we review recent research on species complexes in phlebotomine sand flies from the Americas. Possible practical implications of recently acquired knowledge and future research needs are also discussed.

Bacterial contamination of mobile phones among health care workers: A meta-analysis study

Background Mobile phones (MPs) are becoming commonplace in both community and hospital settings. There are studies that show that phones can be considered fomites in potential, ones that give organisms an environment conducive to their development, such as constant heat and moisture. Aim The present study aimed to do a meta-analysis to investigate the bacterial contamination of MPs among health care workers (HCWs). Materials and methods Using MEDLINE database ( http://www.pubmed.com ), we conducted a systematic literature search to identify relevant studies published within the past 20 years (from 2000 up to 2020). Appropriate articles were accessed in full text to determine eligibility and extract data by two reviewers. Results A total of 18 articles were eligible to this study. Overall, 2300 HCWs were included in all studies. By forest plot test, 78% of HCWs' MPs were found to be contaminated by various types of organisms. The difference between HCWs and non-HCWs is not statistically significant regarding bacterial colonization of MPs. The prevalence of MP colonization by specific bacteria among HCWs was estimated. Coagulase-negative staphylococci were the most prevalent organism found in 50% of the tested HCWs, followed by Escherichia coli 12%, Staphylococcus aureus 11%, Klebsiella 10%, Enterobacter 10%, Proteus 8%, Pseudomonas 7%, Streptococci 7%, aerobic spores 5%, Enterobacter faecalis 2%, and Sphingomonas 2%. Conclusion MP contamination with different organisms is extremely common among HCWs, and resistance of these isolates to various antibiotics has also been detectable. The high level of contamination indicates that the MPs of these professionals may be serving as a reservoir and vehicle in the transmission of pathogenic agents both of hospital origin and community.

Rhipicephalus (Boophilus) microplus and Rhipicephalus sanguineus: a review on the prospects, distribution and resistance

Since the beginning of time animal production is directly influenced by parasites. Among these are the ectoparasites bovine, the tick Ripicephalus (Boophilus) microplus. The control of these mites is done through conventional management with synthetic products, which becomes problematic in the point of view of the resistance of these ticks, directly reflecting in an excessive number of applications allied to dosages above the recommended ones, in smaller intervals than necessary. In this way the number of scientific investigations aiming at the development of less aggressive and more sustainable products is growing. Not less worrisome, Rhipicephalus sanguineus, besides being one of the main parasitic problems faced by kennel owners, has also been found in the home and peri-domiciliary environment of the man who lives with his main urban host, the domestic dog. The R. sanguineus tick species has been found with high prevalence in urban dogs, being described in the literature as one of the main parasite species of these domestic animals. Species evidently involved in the transmission of pathogenic agents, such as Babesia canis, Eherlichia canis and Anaplasma platys. This mite is becoming a real urban pest worthy of attention of the public health organs, and cause for great concern among veterinary professionals.

Evaluation of human cord blood CD34+ hematopoietic stem cell differentiation to megakaryocyte on aminated PES nanofiber scaffold compare to 2-D culture system

Context: Recently, umbilical cord blood (UCB) has been recognized as a suitable potential source of hematopoietic stem/progenitor cells (HSPCs) for transplantation. Lengthy thrombocytopenia after UCB transplantation is a major problem because of insufficient megakaryocyte (Mk) progenitors, which results in delayed platelet recovery. Frequent allogenic platelet transfusion leads to resistance to platelet units and higher risk of transmission of pathogenic agent. Objective: Ex vivo expansion of HSPCs and their differentiation to Mk progenitors on aminated PES nanofiber could lead to faster platelet recovery after UCB transplantation. Materials and methods: CD34 cells were positively enriched using the MidiMACS system. CD34+ cells were seeded onto conventional culture and aminated PES scaffold. The proliferation of CD34+ cells, and also their differentiation into Mk progenitors, were evaluated. We used the flow cytometric method for analyzing CD41 and CD61 markers and real-time PCR for the expression level of transcription factors, as NF-E2 and GATA-1. Results: This study indicated increased CD34+ cell population in aminated PES compared to the conventional system. After differentiation, the amount of CD41/CD61-expressing cells and the quantity of NF-E2 expression level increased in the aminated PES versus the 2-D system. The quantity of GATA-1 expression level was reduced on CD41/CD61+ cells compared to CD34+ cells, with no difference between the aminated PES and the conventional system. Discussion: Aminated PES nanofiber could have more effect on the proliferation of CD34+ cells and Mk differentiation than the conventional culture. Conclusion: Injection of the expanded cells and differentiated Mk progenitors, along with the transplantation of UCB stem cells might accelerate recovery of platelets and decrease the period of thrombocytopenia after transplantation.

P3.009 Prevalence of Chlamydia Trachomatis and Neisseria Gonorrhoea Infection in Pregnant Women Enrolled in a Large Multicenter Clinical Trial

BackgroundPregnant women infected with sexually transmitted diseases are at higher risk for miscarriage, pre-term delivery, low birth weight, and morbidity in the neonate associated with transmission of pathogenic agents. Treatment...

Inactivation des pathogènes des concentrés plaquettaires : expérience française

The transfusion of platelet concentrates is increasing in oncohematology patients due to chemotherapy and hematopoietic stem cell grafts. The transmission of pathogenic agents, viruses, parasites and especially bacteria with platelet concentrates stored at room temperature (20–24 °C) is associated with a septic risk, partly prevented by bacterial detection. Photochemical inactivation of platelet concentrates, using a technique associating amotosalen and UVA, has been used for five years in a French region for the whole population and a large spectrum of patients, with efficacy and safety. Universal implementation of pathogen inactivation in labile blood products is a major and key step to improve safety against infection in transfusion.

The Origin and Prevention of Pandemics

Despite the fact that most emerging diseases stem from the transmission of pathogenic agents from animals to humans, the factors that mediate this process are still ill defined. What is known, however, is that the interface between humans and animals is of paramount importance in the process. This review will discuss the importance of the human-animal interface to the disease emergence process. We also provide an overview of factors that are believed to contribute to the origin and global spread of emerging infectious diseases and offer suggestions that may serve as future prevention strategies, such as social mobilization, public health education, behavioral change, and communication strategies. Because there exists no comprehensive global surveillance system to monitor zoonotic disease emergence, the intervention measures discussed herein may prove effective temporary alternatives.

An evolutionary approach to the high frequency of the Delta F508 CFTR mutation in European populations

The diffusion of the cattle pastoralism across Europe during the Neolithic period was probably accompanied by the emergence and spread of diverse contagious diseases that were unknown in the Paleolithic and that would have affected the frequency of genes directly or indirectly associated with differential susceptibility and/or resistance to infectious pathogens. We therefore propose that the high frequency of the CFTR gene, and in particular, the common Delta F508 allele mutation in current European and European-derived populations might be a consequence of the impact of selective pressures generated by the transmission of pathogenic agents from domesticated animals, mainly bovine cattle, to the man. Intestinal infectious diseases were probably a major health problem for Neolithic peoples. In such a context, a gene mutation that conferred an increased resistance to the diseases caused by pathogens transmitted by dairy cattle would have constituted a definite selective advantage, particularly in those human groups where cow's milk became an essential component of the diet. This selective advantage would be determined by an increased resistance to Cl(-)-secreting diarrheas of those individuals carrying a single copy of the Delta F508 CFTR mutation (heterozygote resistance). This hypothesis is supported by the strong association between the geography of the diffusion of cattle pastoralism (assessed indirectly by the lactase persistence distribution), the geographic distribution of a sizeable number of HLA alleles (as indicative of potential selective pressures generated by epidemic mortality) and the geographic distribution of the most common mutation causing cystic fibrosis (Delta F508). The systematic interaction of humans with infectious pathogens would have begun in northern Europe, among the carriers of the Funnel Beaker Culture, the first farmers of the North European plain, moving progressively to the south with the dissemination of the cattle pastoralism. This gradual exposure to epidemic mortality among populations located further and further south in Europe as cattle pastoralism expanded could have generated differences in CFTR gene frequencies, thereby shaping the latitudinal frequency gradients observed in present-day European populations.

Vectorial role of some dermanyssoid mites (Acari, Mesostigmata, Dermanyssoidea)

Among transmissible diseases, vectorial diseases represent a major problem for public health. In the group of acarina, while ticks are the most commonly implicated vectors, other arthropods and notably Dermanyssoidea are also involved in the transmission of pathogenic agents. Since the role of this superfamily is at present largely unknown, we have reviewed the vectorial role of these mites in the appearance, survival and propagation of pathogens. Various authors have shown that Dermanyssoidea are implicated in the transmission of both bacteria (Salmonella, Spirocheta, Rickettsia or Pasteurella) and viruses (equine encephalitis viruses, West Nile virus, Fowl pox virus, the virus causing Newcastle disease and tick borne encephalitis viruses or hantaviruses). Finally, some authors have also shown their role in the transmission of some protozoa and filaria. As the vectorial character of such mites has been more clearly demonstrated (Dermanyssus gallinae, Omithonyssus bacoti and Allodermanyssus sanguineus), it would be interesting to continue studies to better understand the role of this superfamily in the epidemiology of certain zoonoses.

The Occurrence and Prevention of Infections Associated with Gastrointestinal Endoscopy.

In the four decades since the introduction of flexible endoscopy into medical practice, nearly 300 cases of human infections or pseudoinfections involving bacteria, fungi, parasites, and viruses have been linked to endoscopic procedures. In the majority of such cases, inadequate cleaning and disinfection techniques during the reprocessing of the instruments or their accessories have been likely contributing factors. Working groups from major gastroenterology societies and infection control organizations have established standards of care for the routine maintenance of endoscopic equipment in order to decrease the rates of infection even further. Since the institution of these standards, rates of transmission of infections to patients have decreased, though have not been completely resolved. This article reviews the available literature on transmission of pathogenic agents through endoscopic procedures, summarizes the current guidelines for the care of endoscopic equipment, and discusses available preventive measures aimed at decreasing the risk of endoscopy-related infections.