Vector borne and zoonotic diseases最新文献

Background: Campylobacter jejuni typically causes gastrointestinal illness but may lead to severe systemic infection in immunocompromised hosts. Resistance to macrolides, fluoroquinolones, and tetracyclines is increasingly reported. Case Presentation: A 27-year-old male with X-linked agammaglobulinemia developed recurrent right foot cellulitis after local trauma. Following application of a non-sterile herbal ointment and sheepskin, the lesion progressed, and the patient developed fever and chills. Blood cultures repeatedly yielded multidrug-resistant C. jejuni, while wound culture grew Citrobacter braakii. The C. jejuni isolates showed high MICs to macrolides, fluoroquinolones, and tetracycline. Given persistent bacteremia despite broad-spectrum therapy, meropenem was initiated, resulting in rapid defervescence and clinical improvement. Conclusion: This case highlights the potential for transdermal acquisition of C. jejuni in immunodeficient patients, the clinical challenges posed by multidrug-resistant strains, and the need for education regarding traditional practices that may increase infection risk.

Reactive arthritis is defined as a sterile inflammation of the joint space, following a remote infection, which can be bacterial or viral in origin. Although leptospirosis is not a frequent cause, it has been reported as a potential trigger. We herein report an 11-year-old boy who presented with fever, jaundice, and acute onset of right hip pain with restricted movement. Laboratory investigations were done to evaluate for infectious causes. IgM antibodies for Leptospira were equivocal, suggesting the possibility of an acute infection. This case highlights that reactive arthritis can develop early in the course of leptospiral infection, as early as within 3 days of symptom onset, and may coincide with active systemic illness. Early recognition of this rare association is essential for the diagnosis and management.

Background: Mosquitoes in the genus Culex are vectors of multiple arboviruses, including West Nile virus, St. Louis Encephalitis virus, and Western equine encephalitis virus. In the United States, West Nile (WN) is the leading cause of mosquito-borne diseases, including the El Paso, Texas, and surrounding communities. While Cx. quinquefasciatus, Cx. tarsalis, and Cx. erythrothorax are well documented in the El Paso region, the meteorological effects on the overall abundance and virus transmission risk are not well understood. Our study objective was to estimate temporal population abundance in two urban communities: Sparks, El Paso, Texas, and Anapra, Ciudad Juárez, Chihuahua, Mexico. Materials and Methods: Population abundance was estimated through collections of Cx. quinquefasciatus, Cx. tarsalis, and Cx. erythrothorax from June to December across years 2016-2018 using confirmed human case gravid traps. Mosquitoes were collected inside and outside 108 and 101 participating homes in Sparks and Anapra, respectively. Results: Generally, the results indicated that the abundance of these mosquito species was highest in June, followed by a slight decrease and then an increase in abundance during August, followed by a slight decrease until their near absence in December with colder winter season. The high abundance early in the year could be attributed to overwintering behavior which allowed these species to become dormant and/or diapause until ideal favorable environmental conditions return year after year during the spring season. Conclusion: Interestingly, the overall abundance of Cx. spp. was greater in Anapra, where no WN human cases have been reported. Our study provided a better understanding of the seasonal abundance and risk of arbovirus transmission by these medically important mosquitoes and the need to implement vector control measures early in the year.

Background: Brucellosis is a widespread zoonotic bacterial infection that affects over 500,000 people annually, with significant economic losses in the livestock industry, particularly in endemic regions such as the Middle East, Asia, and parts of Africa and Latin America. Despite standard antibiotic treatments, relapse rates remain as high as 10%-15%, highlighting the limitations of current therapeutic options. Objective: Phage therapy, which uses bacteriophages to selectively target and lyse Brucella spp. bacteria, offers a promising approach for managing brucellosis. Methods: This paper explores the current understanding of brucellosis, highlighting the impact on animal and human health, and reviews the mechanisms and efficacy of bacteriophages against Brucella spp.Results:Key factors, such as phage specificity, immune modulation, and recent advancements in phage encapsulation, are discussed as strategies to enhance treatment efficacy. Conclusion: This review aims to explore emerging alternative therapies beyond conventional antibiotics, focusing on approaches such as immunotherapy, bacteriophage therapy, and novel vaccine strategies to improve clinical outcomes and reduce disease burden.

Background: The Manuel Antonio National Park (MANP) and its surrounding areas in Costa Rica are home to endangered non-human primates (NHPs), including Saimiri oerstedii citrinellus and Cebus imitator, that coexist in close contact with humans and domestic animals. Such interactions may facilitate the transmission of vector-borne zoonotic diseases. This study aimed to investigate the presence of selected vector-transmitted pathogens of zoonotic relevance in NHPs from this region. Methods: Between 2021 and 2022, 40 free-ranging NHPs (19 C. imitator, 19 S. oerstedii citrinellus, 2 Alouatta palliata) were sampled in MANP and surrounding areas. Blood samples were tested for Trypanosoma spp., Plasmodium spp., Mycoplasma spp., and arboviruses including dengue virus (DENV), chikungunya virus (CHIKV), Zika virus (ZIKV), Venezuelan equine encephalitis virus (VEEV), and West Nile virus (WNV). Molecular analyses were conducted using PCR and RT-qPCR protocols, with sequencing for species confirmation. Results: Eight of 40 NHPs (20.0%) tested positive for at least one pathogen. Trypanosoma minasense was confirmed by sequencing in three C. imitator (16.7%). Plasmodium spp. was detected in one C. imitator and one A. palliata (5.0%), though species-level identification was unsuccessful. One C. imitator tested positive for CHIKV (Ct 36.8), representing the first PCR-confirmed case of CHIKV in NHPs in Central America. Two C. imitator were positive for Mycoplasma spp. (11.1%). No co-infections were observed. All animals were negative for DENV, ZIKV, VEEV, and WNV. Conclusions: This study provides the first molecular evidence of CHIKV infection in NHPs in Costa Rica and highlights the circulation of Trypanosoma spp., Plasmodium spp., and Mycoplasma spp. in wild primates from MANP. These findings emphasize the need for a One Health approach to surveillance, particularly in regions where human-wildlife interactions are frequent. Longitudinal and serological studies are recommended to assess the potential reservoir role of NHPs and their implications for public health and conservation.

Background: Hymenolepis diminuta, a rat tapeworm, is a rare zoonosis typically affecting children. We report the first confirmed human case in Yunnan Province, China, not able for its occurrence in an adult. Methods: A 42-year-old female farmer from Dali presented with unilateral painless vision loss. H. diminuta infection was diagnosed incidentally through routine stool microscopy during her ophthalmological workup. Results: Examination of fecal samples confirmed the presence of H. diminuta eggs. This identifies the first autochthonous human case in Yunnan Province and underscores infection in an atypical adult demographic. Conclusion: This case highlights the unexpected detection of a rat tapeworm in a new geographic region and age group, emphasizing the value of basic diagnostics in uncovering zoonotic diseases, even with unrelated clinical presentations.

Background: Tick-borne diseases are an endemic and emerging public health concern in the United States. Ongoing tick range expansion, invasive species, and newly identified pathogens are rapidly altering disease epidemiology. Surveillance is critical to understanding vector ecology and disease risk. Harris County, Texas, with nearly five million residents and diverse ecological zones, offers a unique setting to study local tick dynamics. Methods: From January 2021 to December 2022, we conducted weekly tick surveillance across 63 sites in Harris County (City of Houston), Texas. Ticks were morphologically identified and tested for Rickettsia, Borrelia, Ehrlichia, and Anaplasma via real-time PCR. Samples positive by initial screening were confirmed to the species level using endpoint PCR and sequencing. Results: We collected 1,219 ticks-primarily Ixodes scapularis and Amblyomma maculatum-with distinct seasonal and spatial patterns. Of 1,195 tested ticks, 61% were positive for Rickettsia, with multiple species identified. Notably, Rickettsia parkeri was detected in 23.1% of Rickettsia-positive A. maculatum ticks. Conclusion: Our findings reveal significant tick-borne pathogen activity in Harris County, highlighting the need for continued surveillance and public health efforts in urban and peri-urban Texas.

Background: Monkeypox (Mpox) virus is a virulent zoonotic agent and a member of Poxviridae family. Owing to environmental, social and behavioral factors, and lack of approved vaccines or antiviral agents, the eradication of Mpox has not been successful until today. Material and methods: This study overviewed published data to assess predisposing factors, control strategies and antiviral therapy of mpox virus. Results: The recent Mpox outbreak occurred due to human behavioral factors with a cumulative total of 91,123 laboratory-confirmed cases, including 157 deaths during March 2022-September 2023. Viral immunoregulatory proteins, such as vaccinia complement control protein, inflammation modulatory protein, smallpox inhibitor of complement enzymes, chemokine binding protein, and vaccinia virus growth factor, suppress efficient responses. Host genetic variations in IL1RN (interleukin 1 Receptor Antagonist, rs452204) and IL12RB2 (rs3790567) genes and interferon-α deficiency predispose the host to more severe Mpox infection. Conclusion: Combination therapy and drug repositioning include promising approaches for the efficient antiviral therapy. The worldwide collaboration is required to enhance outbreak preparedness and infection control.

Background: Understanding enzootic cycles is key to arbovirus control. Rodents are primary reservoirs of Venezuelan equine encephalitis virus (VEEV), whereas the vertebrate host of Madariaga virus (MADV) remains unknown. Culex (Melanoconion) mosquitoes are considered primary vectors. We studied small mammals and mosquito ecology in the Darién province and Panamá Oeste province, two enzootic regions of Panama. Additional alphavirus seroprevalence was assessed in small mammals. Methods: Small mammals were trapped using Sherman and Tomahawk traps, and blood samples were tested for MADV and VEEV neutralizing antibodies using plaque reduction neutralization test and attempt viral isolation and generic alphavirus RT-PCR from small mammal tissues. Mosquitoes were collected concurrently using Centers for Disease Control and Prevention (CDC) light, Trinidad, and resting traps. Diversity and similarity were analyzed using standard ecological indices. Results: We sampled 599 small mammals (16 species). MADV seroprevalence was highest in Los Pavitos (9.0%) and restricted to Darién; VEEV was more widespread, peaking in El Cacao (27.3%) and El Real (20.4%). Oryzomys couesi and Transandinomys bolivaris showed elevated MADV seroprevalence; T. bolivaris and Proechimys semispinosus had higher VEEV seroprevalence. Among 4118 mosquitoes, Coquillettidia venezuelensis was most abundant. El Real had the highest species richness and diversity. Geographic proximity influenced community similarity. Conclusions: Spatial differences in host and vector communities may reflect distinct transmission patterns of MADV and VEE. These findings could contribute to better understanding of alphavirus ecology and potentially inform public health strategies in endemic regions.

From 2006 through 2008, 543 synanthropic Rattus norvegicus were sampled from 20 alleys clustered in five high-density human neighborhoods throughout Baltimore, Maryland, USA. Results indicated that rat coronaviruses (RCV) circulated endemically and infected most rats in the region. Collected animals were tested by serology and RT-PCR for evidence of exposure to RCV and the results were used to characterize the epizootiology of natural infection. Serology showed that 71.8% of rats had IgG antibodies to RCV, indicating previous exposure, while only 3.0% showed evidence of recent infection based on positive PCR results. Incidence was estimated at 16% per month. Antibody and PCR results were uniformly distributed throughout the city. Consistent with historical laboratory studies, RCV appeared to be horizontally transmitted and generated an acute infection with a short period of infectiousness. Evidence of past infection increased with rat age but did not differ significantly between males and females. The low incidence (6/1000) of infectious rats (PCR positive/IgG negative) limits the risk of spillover to nearby species, including humans. These results encourage surveys for other wildlife agents to collect sufficient samples to estimate the power to detect the agents and use serological surveys as a screening tool if active infection is of short duration. Otherwise, substantial efforts may be expended with a low likelihood of detection.