Publications by authors named "Nariaki Nonaka"

Alveolar echinococcosis, caused by Echinococcus multilocularis, exhibits significant species-dependent susceptibility. This study compared the early hepatic tissue responses to E. multilocularis in highly susceptible cotton rats (Sigmodon hispidus) and laboratory mice (DBA/2 and AKR/N).

View Article and Find Full Text PDF

Equine piroplasmosis (EP) is a tick-borne disease caused by Theileria equi, Theileria haneyi, and Babesia caballi in equids, such as horses, donkeys, mules, and zebras. A comprehensive understanding of the epidemiology of T. equi and B.

View Article and Find Full Text PDF

Red foxes living in urban areas are called "urban foxes," and their numbers are increasing in Sapporo, northern Japan. Ecological features such as their food habits could have changed compared with foxes in rural areas. To investigate the diet of urban foxes, we developed a method for detecting mammalian prey species by non-invasive fecal DNA analysis.

View Article and Find Full Text PDF

Introduction: This study presents a comprehensive analysis of the complete mitochondrial genomes of isolated from cattle, sheep, and goats in Sudan, aiming to provide new insights into genetic diversity, evolutionary dynamics, and host adaptation.

Methods: Mitochondrial genomes were sequenced using high-throughput Illumina MiSeq technology, yielding sequences of 14,483 bp, slightly longer than the reference genome (14,478 bp). A sliding window analysis was conducted to assess nucleotide diversity, and phylogenetic analyses were performed using complete mitochondrial sequences, including and excluding non-coding regions.

View Article and Find Full Text PDF

The study aimed to determine the prevalence of blood parasites in horses and identify risk factors and molecular detection of piroplasm species (Theileria equi and Babesia caballi) of horses in Myanmar. Blood samples (n = 302) were collected from five regions of Myanmar. Blood smears were screened for presence of piroplasms.

View Article and Find Full Text PDF

Taenia solium is a tapeworm of the family Taeniidae that causes neurocysticercosis, a serious zoonotic disease in humans. Its life cycle involves pigs and wild boars as intermediate hosts and humans as the sole definitive host. Since poor sanitation and free-roaming pigs contribute to maintaining its life cycle, cysticercosis is endemic in developing countries across Asia, Africa, and Latin America, while local transmission is generally absent in developed countries.

View Article and Find Full Text PDF

Fasciola gigantica is an important trematode that affects the health of animals and humans in tropical and subtropical countries, including Malawi. Information on the genetic diversity and population structure of F. gigantica is important to understanding the parasite`s transmission patterns/ and in monitoring the development of resistance to commonly used anthelmintic agents.

View Article and Find Full Text PDF

This study examined the parasite fauna of wild brown bears and differences in the likelihood of parasite detection by season (summer vs autumn), year, and host factors (sex and age class). From June 2022 to November 2024, 334 fecal samples were collected from the Shiretoko Peninsula, Hokkaido, Japan, and examined for parasites using the centrifugal flotation technique. Fecal DNA analysis and data from a long-term field monitoring survey led to the identification of 49 individuals, which were further classified based on sex and age.

View Article and Find Full Text PDF

Gastrointestinal parasites, particularly strongyle nematodes, pose a significant threat to the health of ruminants. Due to the technical limitations of microscopic and conventional PCR-based methods, the strongyle parasite fauna has not been well studied even in common livestock animals. The present study aimed to investigate the prevalence and diversity of strongyle nematodes in three ruminant species in northern Thailand using a nemabiome approach.

View Article and Find Full Text PDF

Background Alveolar echinococcosis (AE) is a fatal zoonotic disease distributed mainly in the Northern Hemisphere. At present, its curative treatment relies on surgery, and the development of effective drugs is needed. We previously demonstrated the anti-echinococcal effect of atovaquone (ATV) as a mitochondrial complex III inhibitor in both in vitro and in vivo experiments.

View Article and Find Full Text PDF

Ixodid ticks are significant vectors of pathogens affecting both humans and animals. Biological control with natural enemies represents a sustainable tool for managing ticks. However, there is a substantial lack of knowledge about the natural enemies of ticks.

View Article and Find Full Text PDF
Article Synopsis
  • Tick-borne pathogens (TBPs) in dogs pose a significant global health threat, particularly in developing countries where surveillance is lacking.
  • A study involving 230 community dogs in Nepal found that 32.6% were infected with at least one TBP, with common pathogens including Ehrlichia canis and Anaplasma platys.
  • The findings suggest that infections in community dogs might pose a risk for transmission to pet dogs and humans, highlighting the need for increased awareness and control measures against these zoonotic parasites.
View Article and Find Full Text PDF

Yezo virus (YEZV) is an emerging tick-borne virus that causes acute febrile illness. It has been continuously reported in patients and ticks in Japan and China since its first identification in Hokkaido, Japan. While serological tests have demonstrated that YEZV infections are prevalent in wild animals, such as raccoons (Procyon lotor), the determinants of infection in wild animals remain largely unknown.

View Article and Find Full Text PDF

Subtropical Asia has a rich diversity of reptiles and ticks, though the role of reptiles in the sylvatic cycles of medically important ticks in the region is poorly known. Habu vipers (Protobothrops flavoviridis) are widespread and common in the Japanese subtropics but their role as hosts for ticks has not been carefully explored. For 15 months in 2023/24, habu vipers were screened for ticks and were found to be important hosts for immature stages of the tick Amblyomma testudinarium, with a 22 % infestation rate.

View Article and Find Full Text PDF

Revealing interactions between ticks and wild animals is vital for gaining insights into the dynamics of tick-borne pathogens in the natural environment. We aimed to elucidate the factors that determine tick infestation in wild animals by investigating ticks on invasive raccoons (Procyon lotor) in Hokkaido, Japan. We first examined the composition, intensity, and seasonal variation of ticks infesting raccoons in six study areas in Hokkaido from March 2022 to August 2023.

View Article and Find Full Text PDF
Article Synopsis
  • Vector-borne parasite infections are common in both domestic and wild animals, often asymptomatic but potentially fatal, particularly under stress.
  • This study focused on the detection and characterization of such parasites in rescued greater one-horned rhinoceroses in Chitwan National Park, Nepal, using advanced molecular techniques on blood samples.
  • Results revealed a 75% prevalence of Theileria bicornis, two new haplotypes, and the presence of Wolbachia and filarial nematodes, indicating a need for enhanced parasite surveillance and further research on wildlife diseases in the region.
View Article and Find Full Text PDF

is a cestode that causes human alveolar echinococcosis, a lethal zoonotic disease distributed in the northern hemisphere. The life cycle of this parasite is maintained in nature by voles as intermediate hosts and foxes as definitive hosts in Hokkaido, Japan. Although dogs are also susceptible to the parasite, the infection has been considered typically asymptomatic.

View Article and Find Full Text PDF

Background: Parasitic infestations have a substantial economic impact on pig production. This study aimed to investigate the gastrointestinal (GI) helminths in pigs and to molecularly characterise two important nematodes, Ascaris and Trichuris species.

Materials And Methods: A total of 500 pig faecal samples were collected from small holder backyard pig farms in five townships within Nay Pyi Taw, Myanmar.

View Article and Find Full Text PDF
Article Synopsis
  • Chickens in free-range environments can be vulnerable to filarioid parasites, but research on these has been limited compared to other pathogens like viruses and bacteria.
  • The study investigated filarioids found in domestic chickens from two flocks in Hiroshima, revealing adult worms and microfilariae in various organs, and showing genetic links to previously identified filarioids from another region in Japan.
  • A new PCR assay was developed to detect the parasite's DNA in biting midges, suggesting these insects could act as vectors for transmission, highlighting the need for further research on these neglected parasites.
View Article and Find Full Text PDF

Spiroplasma (Mycoplasmatales: Spiroplasmataceae) is one of the most widely distributed symbionts of arthropods. Spiroplasma species can infect their hosts via vertical or horizontal transmission. However, the mode of transmission of Spiroplasma between different arthropod taxa has not been elucidated.

View Article and Find Full Text PDF

Animal movement across regions owing to human activity can lead to the introduction of pathogens, resulting in disease epidemics with medical and socioeconomic significance. Here, we validated the hypothesis that human activity, such as the transportation of infected animals, has played a significant role in introducing the zoonotic parasite into Hokkaido, Japan, by synthesizing and evaluating parasite genetic data in light of historical records. Our analysis indicates that a major genetic group in Hokkaido originated from St.

View Article and Find Full Text PDF

Many arthropods harbour bacterial symbionts, which are maintained by vertical and/or horizontal transmission. Spiroplasma is one of the most well-known symbionts of ticks and other arthropods. It is still unclear how Spiroplasma infections have spread in tick populations despite its high prevalence in some tick species.

View Article and Find Full Text PDF

North Africa is home to more than 200 million people living across five developing economies (Egypt, Libya, Tunisia, Algeria, and Morocco) and two Spanish exclaves (Ceuta and Melilla), many of whom are impacted by ticks and tick-borne zoonoses. Populations in Europe are also increasingly vulnerable to North African ticks and tick-borne zoonoses due to a combination of climate change and the movement of ticks across the Mediterranean on migratory birds, human travellers, and trafficked wildlife. The human-biting ticks and tick-borne zoonoses in North Africa are reviewed along with their distribution in the region.

View Article and Find Full Text PDF