Reservoir Of Infection Research Articles

Approbation of the improved staining technique for trematode maritas during parasitological studies in domestic carnivores in the Lipetsk region

The purpose of the research is to validate an optimized protocol for studying helminths using an improved staining method to improve the quality of diagnostics of trematodosis caused by representatives of the Opisthorchidae family. An additional objective was to study the prevalence of infection of definitive hosts within the identified focus of opisthorchiasis in the Lipetsk region.Materials and methods. Liver samples from 10 cats and 5 dogs that died in the Sosna River area (Lipetsk region), where an opisthorchiasis focus had previously been identified, were examined. Helminthological dissection was performed using the Skryabin method. The isolated trematode metacercariae were stained using an improved, previously patented technique based on the method of B. V. Romashov et al. (2003), using Gooch crucibles to improve the quality and convenience of staining. Morphometric studies and species identification of trematodes were carried out. The level of infection was assessed using the indices of number, intensity and prevalence of infection.Results and discussion. A higher prevalence of infection (60%) was found in cats compared to dogs (20%). Among cats, the dominant species was Pseudamphistomum truncatum (infection rate 20.1 ind.). Opisthorchis felineus and Metorchis bilis were also identified. P. truncatum (infection rate 60 ind.) and O. felineus were identified in the infected dog. The improved staining method reduced the examination time and improved the quality of visualization of trematode morphology. The results obtained indicate a wide distribution of P. truncatum among animals of the Lipetsk region and emphasize the significant role of domestic cats as the main reservoirs of infection.

Isolation and Molecular Characterization of Pathogenic Leptospira spp. from Brown Rats (Rattus norvegicus) in Zaria and Environs, Kaduna, Nigeria, 2022.

Leptospirosis caused by the pathogenic serovars of Leptospira spp. is a zoonotic disease of global importance. Brown rats (Rattus norvegicus), due to their worldwide distribution and reservoir host status, are considered the most important reservoir for environmental leptospiral persistence and infections in animals. We aimed to isolate, identify, and characterize Leptospira spp. circulating among brown rat populations in Zaria, Kaduna state, Nigeria. Kidney samples from 305 brown rats from different locations in Zaria were collected April-June 2022 and cultured using bacteriologic methods. We also extracted DNA from 24 kidney tissue samples for molecular detection of pathogenic Leptospira spp. and for phylogenetic analysis. Leptospira spp. was detected in 57.7% of the samples by using culture methods and in 91.7% of the samples by using PCR. The phylogenetic tree revealed two distinct clusters among the reference sequences, aligning with the known P1 and P2 subclades. The sequences from this study all clustered together on the phylogenetic tree and were most similar to Leptospira interrogans serovar Pomona strain RZ 11. The high prevalence of Leptospira spp. detected in Zaria suggests that further surveillance and assessment of the public risk are warranted.

STUDY OF HUMAN LEPTOSPIROSIS IN A TERTIARY CARE HOSPITAL, VISAKHAPATNAM

Objective: Prevalence of leptospirosis in humans is found in an alarming number in recent times. This endemic zoonotic disease is widespread and potentially fatal. It is usually seen in areas with poor socioeconomic conditions, water stagnation, garbage accumulation, which becomes breeding sites for the rodents. Infection may turn epidemic during monsoon. Reservoir of infection is rat scientifically named as Rattus rattus and infection results from direct or indirect exposure to host animals that carry the pathogen in their renal tubules and shed pathogenic leptospires in their urine. The main objective of this study was to estimate the seropositivity of leptospirosis in patients presenting with undifferentiated acute febrile illness for 5 to 7 days during one year period from February 2023 to February 2024 in a tertiary care hospital, Visakhapatnam, India. Methods: A total of 279 blood samples received from suspected cases of leptospirosis were subjected to IgM ELISA. Results: Out of total 279 cases, 20 were positive for leptospirosis (OD ratio ≥1.00). All the positive cases presented with a fever more than 99.5°F, chills and headache with elevated serum procalcitonin levels. Peak incidence of cases was recorded during July and August 2023. Conclusion: Seroprevalence of human leptospirosis in this study was found to be 7.2%.

Extended-Spectrum β-Lactamase-Producing Bacteria from Hospital Wastewater Pipes: Isolation, Characterisation, and Biofilm Control using Common Disinfectants

Hospital wastewater systems have been identified as reservoirs for antibiotic-resistant bacteria, with biofilms harbouring extended-spectrum β-lactamase (ESBL)-producing microorganisms posing significant infection risk. This study focuses on the antimicrobial susceptibility and biofilm control of ESBL-producing bacteria from wastewater pipes from a tertiary care teaching hospital in Ireland, which had experienced endemic infection outbreaks caused by ESBL-producing bacteria.Following isolation of ESBL-producers on selective agar antibiotic susceptibility profiles were determined for a number of antibiotics assessed for their ability to form biofilms. Biofilm eradication studies using the commercially available disinfectants bleach, OptizanTM, VirkonTM, and ClinellTM were performed on selected isolates.ESBL-producing bacteria (n=39 isolates) showed a high degree of resistance to β-lactams. Biofilm-forming ability ranged from non-adherent to strongly adherent and appeared to be source dependent, suggesting the characteristics of the pipe environment played an important role in biofilm formation. All disinfectants showed effective biofilm eradication under suggested working conditions. Effectiveness was significantly reduced following reductions in concentration and contact time, with only ClinellTM showing significant biofilm reduction against all isolates at all concentrations and contact times tested. Of the chlorine-based formulations, OptizanTM frequently outperformed bleach at lower concentrations and treatment times. Biofilm eradication was strain dependent, with varying disinfectant response profiles observed from biofilms from different Stenotrophomonas maltophilia isolates.This study highlights the high degree of ESBL-producing bacteria recovery from patient-facing hospital wastewater apparatus. Their ability to form resident biofilms and act as potential reservoirs of infection emphasises the need for rigorous and effective infection control practices.

Prevalence of Trypanosoma cruzi Infection in Pregnant Women and Risk of Vertical Transmission in Newborns in Chiapas, Mexico.

The Mexican state of Chiapas is considered epidemiologically significant for Chagas disease due to the coexistence of infected reservoirs and vectors, including migratory populations from Central and South America. However, there is a lack of monitoring programs for the timely detection of this disease. The objective of this study was to elucidate the prevalence of Trypanosoma cruzi infection in pregnant women and the risk of vertical transmission in newborns at two hospitals located in the Metropolitan Region of Tuxtla Gutierrez, the capital of Chiapas State Mexico. A cross-sectional study was carried out with 193 pregnant women with gestational ages between 32 and 40 weeks, who underwent immunological testing to diagnose Chagas disease. Conventional PCR testing on cord blood revealed the presence of T. cruzi in newborns. The prevalence of T. cruzi infection in pregnant women was 32.12% (95% confidence interval (CI): 0.25, 0.38). The 62 pregnant women who tested positive for Chagas disease gave birth to 63 children, and in 5 newborns (8% (5/62), 95% confidence interval (CI): 0.02, 0.19), PCR tests on umbilical cord blood were positive for T. cruzi. In conclusion, the dataset showed a high prevalence of Chagas disease in the sample of pregnant women studied and a maternal-fetal transmission rate of 8%.

Morphological and molecular identification of Hymenolepis spp. in Rattus rattus and children with diarrhea from Upper Egypt.

Hymenolepiasis remains among the most common parasitic zoonoses in developing countries. Little information is available about hymenolepiasis in children in Upper Egypt and rodents' contribution to maintaining the disease's epidemiology. A cross-sectional study was carried out to investigate the occurrence of Hymenolepis spp. in Rattus rattus and children in Asyut Governorate, Egypt. Rodents (n = 100) were randomly trapped from various localities in Asyut Governorate, and stool samples from 120 children were collected from the same localities. Laboratory examination of the collected samples involved investigation of the small intestine of R. rattus for adult worm detection by morphological examination, followed by examination of stool samples of children using direct smear, formol-ether sedimentation technique, and Sheather's sugar flotation technique. Confirmation of Hymenolepis spp. positive samples were performed using polymerase chain reaction targeting the internal transcribed spacer 1 (ITS-1) and restriction fragment length polymorphism (PCR-RFLP). This study revealed the occurrence of Hymenolepis spp. in 45% of the examined R. rattus, comprising 43% positivity for H. diminuta and 2% for mixed infection by H. nana and H. diminuta. Hymenolepis nana was detected in 28.3% of the examined children. PCR-RFLP confirmed these findings, showing 100% sensitivity. Collectively, these findings reveal the potential contribution of R. rattus as an important reservoir for Hymenolepis infection in Upper Egypt. This study concluded that personal education, periodical deworming of children, rodent control, and hygienic measures should be implemented by governmental and nongovernmental organizations to reduce the incidence of infection.

HIV DNA Levels in Persons Who Acquired HIV in the Setting of Long-Acting Cabotegravir for HIV Prevention: Analysis of Cases from HPTN 083 and 084.

We evaluated HIV DNA levels in individuals who received long-acting cabotegravir (CAB-LA) or tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) pre-exposure prophylaxis in the HPTN 083 and 084 trials and had HIV DNA testing performed to help determine HIV status. HIV DNA testing was performed using peripheral blood mononuclear cell (PBMC) samples collected after a reactive HIV test was obtained at a study site. DNA was quantified using droplet digital PCR (lower limit of detection [LLOD]: 4.09 copies/million PBMCs). Final HIV status and the timing of the first HIV-positive visit were determined by an independent adjudication committee based on HIV test results from real-time site testing and retrospective testing at a centralized laboratory. HIV DNA testing was performed for 133 participants [21 HIV-positive (7 CAB-LA arm, 14 TDF/FTC arm) and 112 HIV-negative; 1-6 tests/person]. For persons with HIV, the time between the first HIV-positive visit and collection of the first sample for DNA testing was a median of 81 days for those receiving CAB-LA (range 41-246) and 11 days for those receiving TDF/FTC (range 3-127). Four (57.1%) of the seven CAB-LA cases with infection had a low initial DNA result [three detected <LLOD; one near the LLOD (4.2 copies/106 PBMCs); in 2/4 cases, the DNA level was still <10 copies/106 PBMCs ≥40 weeks after the first HIV-positive visit. In contrast, only 3/14 (21.4%) of the TDF/FTC cases had a low or negative initial DNA test result (one not detected; two <10 copies/106 PBMCs). In this study, the time between the first HIV-positive visit and the first DNA test was longer in the CAB-LA cases than the TDF/FTC cases. Despite this difference, low or undetectable DNA levels were more frequently observed in the CAB-LA cases. This suggests that CAB-LA exposure may limit seeding of the HIV reservoir in early infection.

Noninvasive in vivo photoacoustic detection of malaria with Cytophone in Cameroon

Current malaria diagnostics are invasive, lack sensitivity, and rapid tests are plagued by deletions in target antigens. Here we introduce the Cytophone, an innovative photoacoustic flow cytometer platform with high-pulse-rate lasers and a focused ultrasound transducer array to noninvasively detect and identify malaria-infected red blood cells (iRBCs) using specific wave shapes, widths, and time delays generated from the absorbance of laser energy by hemozoin, a universal biomarker of malaria infection. In a population of Cameroonian adults with uncomplicated malaria, we assess our device for safety in a cross-sectional cohort (n = 10) and conduct a performance assessment in a longitudinal cohort (n = 20) followed for 30 ± 7 days after clearance of parasitemia. Longitudinal cytophone measurements are compared to point-of-care and molecular assays (n = 94). Cytophone is safe with 90% sensitivity, 69% specificity, and a receiver-operator-curve-area-under-the-curve (ROC-AUC) of 0.84, as compared to microscopy. ROC-AUCs of Cytophone, microscopy, and RDT compared to quantitative PCR are not statistically different from one another. The ability to noninvasively detect iRBCs in the bloodstream is a major advancement which offers the potential to rapidly identify both the large asymptomatic reservoir of infection, as well as diagnose symptomatic cases without the need for a blood sample.

Camelpox Virus in Western Kazakhstan: Assessment of the Role of Local Fauna as Reservoirs of Infection.

This article investigates the role of local fauna in Western Kazakhstan as potential reservoirs of the camelpox virus (CMLV). The study emphasizes analyzing possible sources and transmission pathways of the virus using polymerase chain reaction (PCR) and serological methods, including virus neutralization tests and enzyme-linked immunosorbent assays (ELISA). Samples were collected from both young and adult camels, as well as rodents, ticks and blood-sucking insects in the Mangystau and Atyrau regions. The PCR results revealed the absence of viral DNA in rodents, ticks and blood-sucking insects; also, the ELISA test did not detect specific antibodies in rodents. These findings suggest that these groups of fauna likely do not play a significant role in the maintenance and spread of CMLV. Consequently, the primary sources of transmission are likely other factors, potentially including the camels themselves. The study's results indicate the need to reassess current hypotheses regarding infection reservoirs and to explore alternative sources to enhance strategies for the control and prevention of the camelpox virus.

Clinical inertia in onychomycosis treatment: results from the Illuminating Dialogues and Insights in Onychomycosis Management (IDIOM) survey.

Onychomycosis is a fungal infection of the nail that can serve as a reservoir for tinea infections in other parts of the body and can be transmitted to other individuals. As the disease progresses, it can lead to functional impairment, such as difficulties in walking, and negatively impact the psychosocial aspects of quality of life. Onychomycosis treatment, especially topical, is long-term, and adequate follow-up is essential for cure. However, the realities and issues of patient-physician communication after treatment initiation, including patients' perception of efficacy, treatment satisfaction, and reconsideration of the treatment approach, remain unclear. Therefore, this study aimed to examine the realities and issues associated with onychomycosis treatment, focusing on topical therapies, through a web-based survey of patients with onychomycosis and dermatologists. The duration of topical treatment was prolonged, with 30.5% of patients undergoing topical therapy for more than 2 years. Of these, 54.5% had not perceived clear efficacy. In addition, 93.7% of all patients with onychomycosis expressed a desire to change their treatment if it was ineffective. However, only 29.9% of patients receiving topical treatment discussed changing their treatment with their physicians, and only 7.3% ultimately changed their treatment. These findings indicate that the review of treatment strategies was insufficient. Furthermore, the satisfaction rate among patients treated with oral medications was higher than that of patients treated with topical medication. Despite dermatologists' awareness of low patient satisfaction with topical treatments, approximately 40% recommended alternative topical therapies when the initial topical treatment was ineffective. These results suggest clinical inertia in the treatment of onychomycosis stemming from a lack of appropriate intensification of treatment. In managing onychomycosis, the patient and dermatologist must share a common understanding of the importance of regular evaluation and the optimization of treatment regimens during treatment and must work side by side toward a cure.

Wildlife as Reservoirs of Encephalitozoon Cuniculi and Encephalitozoon Hellem and Molecular Genotyping of Encephalitozoon spp. in Small Mammals in the Czech Republic.

Parasites of genus Encephalitozoon are well known pathogens of domestic animals however less attention was paid to its spread among wildlife that can play an important role of reservoir of infection. The aim of the study was to conduct molecular detection and genotype characterization of Encephalitozoon spp. in wild small mammals trapped in localities both near to and at a large distance from residential areas. In total, 300 wild small mammals (274 Rodentia and 26 Eulipotyphla) were trapped in 41 localities of the Czech Republic and tested by nested PCR for Encephalitozoon spp. The DNA of Encephalitozoon spp. was proved in tissues (brain or liver) of 11% (32/300) of animals. There was a statistically significant difference (p < 0.001) in positivity among animal species with the most infected species Micromys minutus (50%, 4/8) and Myodes glareolus (17%, 9/53). There was also statistically significant difference (p < 0.001) between localities with the higher positivity (29%, 12/42) in localities near to residential areas, compared to localities with a large distance from residential areas (8%, 20/258). Sex and age of wild small mammals did not have effect on their positivity. Genotyping analysis revealed E. cuniculi genotype II in 22 samples and E. hellem genotype 1A in one sample. This study brings new information on the molecular characterization of Encephalitozoon spp. isolated from wild small mammals trapped in two different areas (localities in near to residential areas and localities with a large distance from residential areas).

High chytrid prevalence and infection intensities in tadpoles of Mixophyes fleayi

Context The amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd) has caused catastrophic biodiversity loss globally, but species and life stages within species respond differently to the pathogen. Although tadpoles are often reported to be less vulnerable to disease, they can constitute important infection reservoirs in ecosystems. Aims We aimed to describe Bd infection patterns of a long-lived tadpole in a species where post-metamorphic animals appear to exhibit limited mortality as a result of chytridiomycosis. We further investigated how oral dekeratinisation can be used as an indicator of infection. Methods We conducted surveys of tadpoles of Mixophyes fleayi (Fleay’s barred frog) over 2 years, at two rainforest streams on the east coast of Australia, to assess patterns in Bd infection prevalence and intensity. We developed an integrated hierarchical model propagating pathogen-detection errors and incorporating how Bd infections affect oral dekeratinisation. Key results We found that Bd infection prevalence was strongly associated with lower temperatures and a larger body size, consistent with Bd optimal thermal range and a cumulative risk of exposure for tadpoles. The individual probability of a tadpole being infected with Bd was estimated to be 0.58 [95% HPDI: 0.432, 0.713], the odds of which were approximately eight times greater than for adults at the same sites. Tadpoles infected with Bd were 113 [29, 293] times more likely to have oral dekeratinisation than were uninfected tadpoles, where uninfected individuals were estimated to have a 0.05 [95% HPDI: 0.011, 0.11] probability of having mouthpart loss. Conclusions Our results showed that M. fleayi tadpoles are more likely to be infected with Bd than are adults, suggesting that tadpoles could contribute to Bd maintenance in streams. We further showed that sites can be rapidly assessed for Bd by visually checking for oral dekeratinisation. Implications Long-lived tadpoles, in general, may contribute to Bd maintenance in ecosystems. We suggest continued exploration of Bd immunocompetence across amphibian life stages to further understand the vastly different infection patterns.

Molecular Testing of Environmental Samples as a Potential Source to Estimate Parasite Infection.

We discuss the potential usefulness of molecular testing of soil, dust, and water samples to detect medically important parasites, and where such testing could be used to supplement stool sampling in humans. A wide variety of parasites including protozoa and helminths, many of which are zoonotic, have an important infection reservoir in the environment. In some cases, this environmental period is essential for further parasite development. We describe the progress in implementing methods for the molecular detection of these parasites in soil across eight collaborating centers in Latin America and represent a variety of potential applications in improving our understanding of parasite epidemiology and mapping, surveillance, and control of these parasites. This methodology offers new opportunities for improving our understanding of a wide variety of parasites of public health importance and novel tools for their control.

Carbapenem-Resistant Enterobacter hormaechei Uses Mucus Metabolism to Facilitate Gastrointestinal Colonization.

Bloodstream infections caused by Enterobacter species pose a significant clinical threat. The intestine acts as the primary site for colonization and serves as a reservoir for infection. To combat this pathogen, it is crucial to understand how carbapenem-resistant Enterobacter species colonize the gut, as such knowledge can pave the way for alternative therapeutic targets. In this study, we developed a novel neonatal mouse model for gastrointestinal colonization by Enterobacter species and discovered that mucus plays a key role as a carbon source during colonization. Additionally, we identified two mucus catabolism pathways that contribute to intestinal colonization by carbapenem-resistant E. hormaechei. This new mouse model offers valuable insights into host-pathogen interactions and helps identify critical gastrointestinal fitness factors of Enterobacter, potentially guiding the development of vaccines and alternative therapeutic strategies to minimize intestinal carriage in patient populations at risk for infection with Enterobacter species.

Conjugation of anti-HIV gp41 monoclonal antibody to a drug capable of targeting resting lymphocytes produces an effective cytotoxic anti-HIV immunoconjugate.

HIV-infected cells persisting in the face of suppressive antiretroviral therapy are the barrier to curing infection. Cytotoxic immunoconjugates targeted to HIV antigens on the cell surface may clear these cells. We showed efficacy in mouse and macaque models using immunotoxins, but immunogenicity blunted the effect. As an alternative, we propose antibody drug conjugates (ADCs), as used in cancer immunotherapy. In cancer, the target is a dividing cell, whereas it may not be in HIV. We screened cytotoxic drugs on human primary cells and cell lines. An anthracycline derivative, PNU-159682 (PNU), was highly cytotoxic to both proliferating and resting cells. Human anti-gp41 mAb 7B2 was conjugated to ricin A chain or PNU. The conjugates were tested in vitro for cytotoxic efficacy and anti-viral effect, and in vivo for tolerability. The specificity of killing for both conjugates was demonstrated on Env+ and Env- cells. The toxin conjugate was more potent and killed more rapidly, but 7B2-PNU was effective at levels achievable in patients. The ricin conjugate was well tolerated in mice; 7B2-PNU was toxic when administered intraperitoneally but was tolerated intravenously. We have produced an ADC with potential to target the persistent HIV reservoir in both dividing and non-dividing cells while avoiding immunogenicity. Cytotoxic anti-HIV immunoconjugates may have greatest utility as part of an "activate and purge" regimen, involving viral activation in the reservoir. This is a unique comparison of an immunotoxin and ADC targeted by the same antibody and tested in the same systems.IMPORTANCEHIV infection can be controlled with anti-retroviral therapy, but it cannot be cured. Despite years of therapy that suppresses HIV, patients again become viremic shortly after discontinuing treatment. A long-lived population of memory T cells retain the genes encoding HIV, and these cells secrete infectious HIV when no longer suppressed by therapy. This is the persistent reservoir of HIV infection. The therapies described here use anti-HIV antibodies conjugated to poisons to kill the cells in this reservoir. These poisons may be of several types, including protein toxins (immunotoxins) or anti-cancer drugs (antibody drug conjugates, ADCs). We have previously shown that an anti-HIV immunotoxin had therapeutic effects in animal models, but it elicited an anti-drug immune response. Here, we have prepared an anti-HIV ADC, which would be less likely to provoke an immune response, and show its potential for use in eliminating the persistent reservoir of HIV infection.

Co-Designing Digital Health Intervention for Monitoring Medication and Consultation Among Transgender People in Underserved Communities: Collaborative Approach.

In many parts of the world, men who have sex with men and transgender individuals face criminalization and discrimination. As a result, they are less likely to seek medical help, despite experiencing higher rates of HIV/AIDS, mental health issues, and other health problems. Reaching key populations (KPs) with essential testing, care, and treatment services can be challenging, as they often have a higher likelihood of contracting and spreading the virus. They have limited access to antiretroviral (ARV) therapy (ART) services, which means that KPs may continue to serve as reservoirs for new HIV infections if they do not receive effective HIV programming. This ongoing issue complicates efforts to control the epidemic. Therefore, modeling a digital health system to track ARV medication access and use is crucial. This paper advocates for the use of digital interventions to manage the health of KPs in underserved regions, using Nigeria as a case study. This study aims to assess digital health interventions for monitoring medication and consultations among transgender people in underserved communities. It also sought to determine whether a system exists that could support ART adherence in Nigeria. Additionally, the study evaluated design strategies to address privacy and confidentiality concerns, aiming to reduce nonadherence to ARV medications among KPs in Nigeria. A qualitative approach was adopted for this research, involving a thematic analysis of information collected from interviews with clinicians and other health practitioners who work directly with these communities, as well as from an interactive (virtual) workshop. The findings from the thematic analysis indicate a need to increase attendance at ART therapy sessions through the implementation of an intensive care web app. Unlike previous solutions, this study highlights the importance of incorporating a reminder feature that integrates with an in-app telemedicine consultancy platform. This platform would facilitate discussions about client challenges, such as adverse drug effects, counseling sessions with clinical psychologists, and the impact of identity discrimination on mental health. Other data-driven health needs identified in the study are unique drug request nodes, client-led viral load calculators, remote requests, and drug delivery features within the web app. Participants also emphasized the importance of monitoring medication compliance and incorporating user feedback mechanisms, such as ratings and encouragement symbols (eg, stars, checkmarks), to motivate adherence. The study concludes that technology-driven solutions could enhance ART adherence and reduce HIV transmission among transgender people. It also recommends that local governments and international organizations collaborate and invest in health management services that prioritize health needs over identity.

ANTICIPATING BIOSECURITY HAZARDS: DISTRIBUTION AND RECOGNITION OF BIOLOGICAL THREATS

Understanding the potential biological weapons that can be created, the technologies involved, and the entities capable of producing them is crucial for biosecurity. Equally important is comprehending the various targets a biological weapon might be aimed at, the deployment methods, and available detection strategies to counteract illegal biological threats. This chapter delves into these aspects, starting with methods of deployment. The Center for Disease Control and Prevention (CDC) categorizes disease transmission into direct and indirect modes. Direct transmission involves contact with an infected person or environmental reservoir, including droplet spread, proven highly effective in densely populated areas. Indirect transmission occurs through contaminated objects or vectors. Vehicle-based transmission involves contaminating inanimate objects like food, water, and biological products. Vector-based transmission involves organisms carrying and transmitting pathogens. Airborne transmission, receiving significant attention for its potential in biological attacks, involves pathogens suspended in the air, posing significant risks, especially in crowded areas. Biological weapons could target humans, agriculture, technology, and the environment. Attacks on humans, often the focus of biosecurity efforts, pose catastrophic outcomes. State-sponsored programs often focus on human pathogens like Bacillus anthracis and Yersinia pestis. Agroterrorism, targeting agriculture and livestock, can lead to economic losses and social instability. Attacks on technology, utilizing synthetic biology, have shown the potential to manipulate DNA to store and deploy malicious code, highlighting vulnerabilities in sequencing systems. While attacks on the environment remain theoretical, advancements in gene drives raise concerns about manipulating ecosystems. Effective biosecurity involves pre- and post-deployment screening techniques. Pre-deployment screening, particularly gene synthesis, focuses on preventing the acquisition of DNA fragments for weapon production. Current measures involve background checks and screening against pathogen lists, yet gaps exist, including inadequate international policies and the potential to hide malicious sequences within longer ones. Post-deployment detection relies on traditional molecular diagnostic methods, but synthetic pathogens may evade detection, necessitating ongoing advancements in detection techniques. Real-time sensors and biosensors offer promising avenues for quick and accurate pathogen recognition, although challenges remain in detecting novel pathogens against a natural background. In conclusion, understanding the range of biological weapons, their potential targets, deployment methods, and detection strategies is essential for effective biosecurity. Continued research and advancements in detection technologies are crucial to staying ahead of evolving biological threats, ensuring a safer and more secure future.

MOLECULAR AND MORPHOLOGICAL CHARACTERIZATION OF SARCOCYSTIS INFECTIONS IN THE MUSCLES OF GRAY WOLVES (CANIS LUPUS) FROM MINNESOTA SUGGEST THEY MAY SERVE AS RESERVOIRS FOR INFECTION IN DOMESTICATED DOGS.

Sarcocystis infections were found for the first time in the muscles of 3 of 3 gray wolves (Canis lupus) from Minnesota. Two kinds (thin-walled and thick-walled) of sarcocysts were detected, based on the appearance of the sarcocyst wall. In wolf 1, sarcocysts were thin-walled (<0.5 μm), and without any visible protrusions. Ultrastructurally, the sarcocyst wall was type 1a and identical to Sarcocystis svanai of the domestic dog (Canis familiaris). The second kind of sarcocyst, with a relatively thicker (>1 μm) sarcocyst wall, was detected in wolves 2 and 3. Ultrastructurally, the sarcocyst wall had undulating, pleomorphic villar protrusion of type 9c; these sarcocysts were identical to Sarcocystis caninum from the domestic dog. Molecularly, the 2 Sarcocystis species were characterized using 18S, 28S, COI, ITS-1, and rpoB genetic markers. All these markers showed 100% identity to either of the 2 species previously described from the domestic dog. The thick-walled sarococyst corresponded to Sarcocystis caninum, whereas the thin-walled sarcocyst corresponded to Sarcocystis svanai.

Enzymatically enhanced ultrastructure expansion microscopy unlocks expansion of in vitro Toxoplasma gondii cysts.

Toxoplasma gondii is an intracellular parasite capable of establishing long-term chronic infection in nearly all warm-blooded animals. During the chronic stage, parasites encapsulate to form cysts predominantly in neurons and skeletal muscle. Current anti-Toxoplasma drugs do not eradicate chronic parasites, leaving a reservoir of infection. The cyst is critical for disease transmission and pathology, yet it is harder to study, with the function of many chronic-stage proteins still unknown. Ultrastructure expansion microscopy, a new method to overcome the light microscopy's diffraction limit by physically expanding the sample, allowed in-depth studies of acute Toxoplasma infection. We show that Toxoplasma cysts resist expansion using standard protocol, but an additional enzymatic digestion with the mucinase StcE allows full expansion. This protocol offers new avenues for examining the chronic stage, including precise spatial organization of cyst-specific proteins, linking these locations to morphological structures, and detailed investigations of components of the durable cyst wall.

Bat Rabies in the Americas: Is Myotis the Main Ancestral Spreader?

The rabies virus (RABV) is the exclusive lyssavirus affecting both wild and domestic mammalian hosts in the Americas, including humans. Additionally, the Americas stand out as the sole region where bat rabies occurs. While carnivore rabies is being increasingly managed across the region, bats are emerging as significant reservoirs of RABV infection for humans and domestic animals. Knowledge of the bat species maintaining rabies and comprehending cross-species transmission (CST) and host shift processes are pivotal for directing surveillance as well as ecological research involving wildlife reservoir hosts. Prior research indicates that bat RABV CST is influenced by host genetic similarity and geographic overlap, reflecting host adaptation. In this study, we compiled and analyzed a comprehensive nucleoprotein gene dataset representing bat-borne RABV diversity in Argentina and the broader Americas using Bayesian phylogenetics. We examined the association between host genus and geography, finding both factors shaping the global phylogenetic structure. Utilizing a phylogeographic approach, we inferred CST and identified key bat hosts driving transmission. Consistent with CST determinants, we observed monophyletic/paraphyletic clustering of most bat genera in the RABV phylogeny, with stronger CST evidence between host genera of the same family. We further discuss Myotis as a potential ancestral spreader of much of RABV diversity.