Journal of Arthropod-Borne Diseases最新文献

Background: Cockroaches, recognized as mechanical vectors, play a crucial role in transmitting microbial pathogens. Staphylococcus aureus (S. aureus), particularly antibiotic-resistant strains, poses a significant threat as a nosocomial pathogen. This study aimed to investigate the resistance profiles to gentamicin, vancomycin, and antiseptics in S. aureus strains isolated from cockroaches in hospitals affiliated with Babol University of Medical Sciences.

Methods: In this cross-sectional study, 60 S. aureus strains were isolated from 376 cockroaches in three university-affiliated hospitals. Antibiotic susceptibility to gentamicin and vancomycin was tested by disk diffusion and agar dilution. PCR was used to detect resistance and antiseptic genes, and MLVA typing determined the genetic relatedness of resistant isolates.

Results: Among the 60 bacterial isolates, 46.7% (28) displayed resistance to gentamicin. The frequencies of aminoglycoside resistance coding genes (AMEs) for the aac(6')-Ie+aph(2″), ant(4')-Ia, aph(3')-IIIa and ant(6)-Ia genes were 64.3%, 42.8%, 17.8%, and 46.4%, respectively. Only 3.3% (2 isolates) exhibited vancomycin resistance, with one isolate (1.7%) carrying the vanA gene. The frequencies of genes encoding the antiseptic resistance genes qacA/B, qacC, qacD, psmA, sasX, and smr were 5%, 20%, 18.3%, 26.4%, 1.2%, and 31.7%, respectively. Analysis of agr gene types showed that agr type I was the most prevalent. In addition, the multiple-locus variable number tandem-repeat analysis (MLVA) identified 29 unique type sequences among the identified antibiotic-resistant isolates.

Conclusion: The high genetic diversity among antibiotic-resistant S. aureus isolates, as revealed by MLVA, underscores the importance of controlling hospital cockroach populations to curb the spread of antibiotic resistance.

Background: Rat populations in urban areas must be monitored and controlled, as they can transmit zoonotic diseases and pose a risk to human health. Certain urban rat species may not respond well to some of the rodenticides available on the market. Therefore, this study aimed to assess the efficacy of chlorophacinone in controlling urban rats in a laboratory setting.

Methods: Chlorophacinone, the primary focus of this study, was compared to a commonly used first-generation anticoagulant rodenticide (FGAR) available in the urban market, namely Coumatetralyl. Rat specimens were trapped in Kuantan, Pahang, and the dominant species was identified as Rattus norvegicus.

Results: Overall, chlorophacinone demonstrated nearly complete mortality (95%) within an average of eight days post-feeding, followed by coumatetralyl, which exhibited high mortality (85%) within an average of seven days post-feeding. The rats in the chlorophacinone group consumed significantly lower dosages than those in the coumatetralyl group. This was due to variations in the default concentrations of the active ingredient of both treatments. Nevertheless, rats in the chlorophacinone treatment still experienced a higher mortality rate compared to coumatetralyl, despite consuming a lower dosage.

Conclusion: Consequently, this finding suggests that R. norvegicus is more susceptible to chlorophacinone than coumatetralyl. This underscores the potential of chlorophacinone as an effective rodenticide for controlling rat infestations in urban areas throughout Malaysia.

Introduction: Mosquitoes transmit several diseases to humans. New and environmentally safe methods are needed to control mosquito populations effectively. This study aimed to evaluate the larvicidal and repellent properties of extracts and silver nanoparticles synthesized from Zataria multiflora (Shirazi thyme).

Methods: To determine the larvicidal and repellent properties of Z. multiflora, we tested different concentrations of synthesized silver nanoparticles and crude extract against this malaria vector.

Results: The crude extract exhibited weak larvicidal activity, with an LC₅₀ of 616.52 μg/mL and an LC₉₀ of 1109.74 μg/mL. However, the synthesized silver nanoparticles are highly active on the larvae of Anopheles stephensi, with an LC₅₀ at 51.07 μg/mL and an LC₉₀ at 119.04 μg/mL. Both the crude extract (ED₅₀: 0.00031 μg/cm²; ED₉₀: 0.0018 μg/cm²) and silver nanoparticles (ED₅₀: 0.000072 μg/cm²; ED₉₀: 0.00048 μg/cm²) demonstrated significant repellent activity. Particle size analysis revealed a range of 24.56 to 63.76 nanometers, with an average size of 52.7 nanometers.

Conclusion: This study showed that Z. multiflora silver nanoparticles have significant larvicidal properties, so they are suggested as a nature-friendly larvicide.

Background: Global trade and travel are key factors affecting the initial introduction of vectors and VBDs (vector-borne diseases) in a country. Vectors know no borders; it is essential to establish systems for the surveillance of vectors and vector-borne diseases (VBDs). This study was conducted to investigate the strengths and weaknesses of a newly established entomological surveillance system for Aedes mosquitoes at points of entry (PoE) in West Azerbaijan Province.

Methods: The Aedes surveillance system was implemented in West Azerbaijan Province from 2019 to 2023. Following national guidelines, Aedes eggs and larvae were surveyed at eight international PoEs using ovitraps and by collecting larvae from natural or artificial habitats. A specific checklist designed for this study was employed to evaluate the program.

Results: Over 9008 ovitraps were deployed, while 552 had eggs, including species from the families Phasmatidae and Psychodidae, as well as species from the genus Culex and Aedes caspius. Additionally, 506 larvae were collected during the surveillance period. The program had several key strengths, including a well-structured reporting system, robust technical support, knowledgeable personnel, designated health staff spaces at PoE, standardized surveillance tools, initiatives for environmental enhancement, the establishment of an entomology laboratory, cross-border collaborations, and public health education campaigns. Identified weaknesses comprised staff and entomologist shortages, the absence of a functional insectary, limited engagement of volunteer groups, and inadequate availability of insecticides and tools for emergency vector control.

Conclusions: The study outcomes shed light on the challenges and suggest operational and practical solutions to address the identified shortcomings.

Background: Phlebotomine sand flies are the primary vectors of cutaneous leishmaniasis. We conducted a field survey and comprehensive literature review to investigate the species composition and bionomics of sand flies in Mashhad, a major pilgrimage and tourist city in northeastern Iran. This location is critical due to its high population mobility, which can influence disease dynamics.

Methods: Sand flies were collected monthly from spring to winter 2022 using sticky paper traps at 108 sites across Mashhad's diverse ecological zones. Species were identified, and population densities were calculated. Climatic data for 2022 were sourced from the Mashhad Meteorological Station. Using SPSS version 26, we employed ANOVA to compare seasonal species densities and Pearson correlation to analyses relationships between climatic parameters and sand fly abundance.

Result: A total of 3,270 sand fly specimens were collected, representing two genera. The majority (98%) belonged to the genus Phlebotomus, while the remaining 2% were classified under Sergentomyia. The identified species and their respective relative abundances were as follows: Ph. sergenti (76.29%), Ph. papatasi (18.53%), Ph. alexandri (1.10%), Ph. ansari (1.00%), Se. sumbarica (1.31%), Ph. caucasicus (0.73%), Ph. major group (0.61%), and Se. sintoni (0.42%). Statistical analysis revealed significant seasonal variations in the abundance and distribution of sand fly species, which were strongly associated with environmental parameters such as temperature, wind speed, and relative humidity.

Conclusion: The bionomics, diversity, and population density of sand flies vary across different locations and times, a factor that must be considered in advanced studies, prevention, and control programs.

Background: Trypanosomosis is one of the most important and deadliest diseases of canines. Usually within 3 to 4 weeks an infected dog dies in the acute form of the disease. The use of inappropriate doses of anti-trypanosomatid drugs in animals leads to the development of huge resistance in the organisms.

Methods: The present study communicates the successive therapeutic management of clinical trypanosomiasis with five doses of diminazine aceturate injection. One mongrel dog came with the clinical signs of persistent fever, tachycardia, severe dehydration, pale mucous membrane, corneal opacity, prolonged recumbency, and enlargement of superficial lymph nodes. A Giemsa-stained thin blood smear revealed the presence of Trypanosoma organisms. Haematobiochemical parameters revealed lowered total leucocyte count, haemoglobin, total platelet count, serum total protein, and blood glucose levels and elevated levels of alkaline phosphatase, serum creatinine, and blood urea nitrogen.

Results: We observed the animal responded after the third day of post-therapy, and the clinical and haematobiochemical improvement was recorded after twenty days of post-therapy. The corneal opacity completely subsides after 28 days consequently.

Conclusions: During our study we found that the proper significant dosing of diminazine aceturate can cure the Trypanosomosis in dogs.

Background: Zoonotic cutaneous leishmaniasis (ZCL) is one of the most prevalent vector-borne diseases. The understanding of the knowledge, attitudes, and practices regarding ZCL in Iran has not been thoroughly examined. This investigation focused on the risk factors for ZCL within an endemic region in the Mehran District of Ilam Province.

Methods: This case-control study was conducted from 2022 to 2023. Cases (n=372) were selected using the incident case approach from the Centers for Disease Control (CDC). Similarly, 372 controls were chosen through cluster random sampling from the general population. To measure exposure to various risk factors, a validated, research-developed questionnaire was utilized. Binary logistic regression modelling was employed to assess the association between the development of leishmaniasis and several risk factors. A p-value of 0.05 was set as the threshold for statistical significance.

Results: Living near rodent nests or holes (Odds Ratio: 6.51), having bathroom and toilet located outside the house (OR: 5.88), residing close to farms or gardens (OR: 8.26) or specific plants (OR: 6.22), observing a rodent near one's home (OR: 2.66), and the accumulation of building debris near residential areas (OR: 13.03) significantly increased risk of developing cutaneous leishmaniasis. In contrast, the use of insecticides (OR: 0.03) and lotions or other insect repellents (OR: 0.31) significantly decreased the risk of this disease.

Conclusion: The development of ZCL in the Mehran district, Ilam province, southwest Iran, is hindered by inadequate health education and public awareness regarding the disease, as well as insufficient adherence to Iran's care guidelines.

Background: Drugs or poisons can affect the larvae's developmental period in cadavers, leading to variations in the post-mortem interval (PMI) calculation. One of the most misused psychostimulant drugs in Asia and North America, Methamphetamine (MA), is commonly involved in forensic entomotoxicological situations. This study investigated the impact of various MA concentrations on the developmental rate, morphology, and behavior of Lucilia sericata.

Methods: Lucilia sericata was maintained at 28 °C and 50±10% humidity in the Calliphoridae breeding laboratory at the School of Public Health, Tehran University of Medical Sciences. Chicken liver substrates with varying concentrations of MA (0, 45, 90, and 180 ng/mg) were used to produce L. sericata eggs. Ten samples were randomly selected from each treatment group for morphological analysis, including weight and size measurements, at each sampling stage (every 12 hours up to 300 hours). With a significance level of p< 0.05, the General Linear Model (GLM) Mixed Model ANOVA was used to compare the data.

Results: The development time of L. sericata was shown to be changed by Methamphetamine concentrations, which decreased by 24 hours at 90 and 180 ng/mg. Compared to the control group, larvae and pupae lengths decreased by 1.22 and 0.7 mm, respectively, at 180 ng/mg. Additionally, the weight of the larvae and pupae in the concentration mentioned above decreased by 7.52 and 7 mg, respectively, in comparison to the control group.

Conclusion: The PMI is estimated incorrectly if the presence of Methamphetamine in the corpse is disregarded.

Background: Emergent vector-borne diseases have gained significant attention in recent years due to their increasing prevalence and impact on public health. With its vast geographic and ecological diversity, Algeria has limited available data on the distribution and prevalence of neglected vector-borne diseases. This study aimed to inventory hematophagous ectoparasites, including ticks and fleas, collected from domestic and wild animals such as dogs, hedgehogs, cattle, and rodents across diverse biotopes in northwestern Algeria (Mascara, Oran, Tlemcen, Sidi Bel Abbes, Mostaganem, Tiaret, and Ain Temouchent) and southern Algeria (Laghouat).

Methods: A total of 984 arthropods, comprising 609 ticks and 375 fleas, were collected from domestic and wild animals. Among these, 193 ticks and 105 fleas underwent molecular screening for Rickettsia spp. using gltA and ompA gene-specific primers.

Results: The minimum infection rate (MIR) for Rickettsia spp. was estimated at 6.37%, assuming one positive individual per pool. Quantitative PCR revealed the presence of Rickettsia massiliae in 1/68 (1.47%) of Rhipicephalus sanguineus ticks and Rickettsia felis in 7/48 (14.58%) of Ctenocephalides felis fleas. Additionally, a novel strain of Rickettsia sp. was identified in Rhipicephalus sanguineus and Rhipicephalus turanicus.

Conclusion: This study expands the understanding of tick- and flea-borne Rickettsia species in Algeria, highlighting the diverse range of ectoparasite-borne pathogens associated with domestic and wild animals. The findings underscore the importance of continued surveillance and molecular characterization to address the public health risks posed by these pathogens.