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Urban greening has become an increasingly popular strategy to improve urban life and human health. However, there are indications that the presence and extent of urban greenness may increase the abundance of wild rats. Therefore, we investigated which environmental and socio-economic factors are associated with rat abundance, with a focus on factors related to urban greenness. We systematically trapped rats (222 Rattus norvegicus and 5 Rattus rattus) in parks and residential areas in three cities in the Netherlands. We modelled the relative abundance of rats against various environmental and socio-economic variables. In addition, we compared municipality rat complaint data with our trapping data and analysed trap success over time. We observed positive relationships between the relative abundance of rats and both greenness (NDVI) and different proxies for food resources (restaurants and petting zoos). In addition, there were more municipality rat complaints in residential areas compared to parks, while there was a higher relative abundance of rats in parks. Our findings corroborate that greenness is associated with a higher abundance of wild rats, and that municipality rat complaints may underestimate the abundance of rats in greener urban areas. This study provides new insights on factors affecting relative rat abundance in cities and can guide policy makers and city planners how to minimize rat nuisance in the greener parts of cities. By taking these potential effects of urban greenness on rat abundance into account, measures can be taken that on the one hand maintain the beneficial effects of urban greening, but at the same time reduce the carrying capacity for rats. [ABSTRACT FROM AUTHOR]

Background: The protozoan Toxoplasma gondii is the source of zoonosis toxoplasmosis and causes public health problems throughout the world. Environmental contamination by oocysts excreted by cats as definitive hosts affects the spread of this disease. Wild rats as rodents can be used as an indicator of environmental contamination by oocysts, considering that rats have a habit of living in dirty environments and can be infected by oocysts from the environment. Aim: This study aims to detect toxoplasmosis from tissue cysts and serological tests in wild rats as an indicator of environmental contamination in Surabaya. Methods: A total of 100 wild rats collected from Surabaya were collected in five areas (West, East, Central, North, and South of Surabaya) obtained from three trapping locations: housing, dense settlements, and markets. All samples were examined microscopically for parasitological tests through the brain tissue samples, and the serum was examined using the toxoplasma modified agglutination test to detect the presence of IgG and Immunoglobulin M (IgM). Results: This research used 100 wild rat samples, 77 Rattus tanezumi and 33 Rattus norvegicus, with evidence of 31% in serology and active infection with 19% tissue cyst. The results showed that the seroprevalence of T. gondii in wild rats was 31% (30% for IgG and 1% for IgM). Tissue cysts in the rat brain samples tested were 19% (19/100). The IgG prevalence rate in female rats was 25% (8/32), while for males, it was 32.3% (22/68). The highest seropositive IgG from densely populated settlements was 50%, markets were 25.8%, and housing was 12.1%. The highest seropositive IgM from densely populated settlements was 2.8%. Population density and the presence of cats are factors supporting the high seropositive rate at the trapping location. Conclusion: This study revealed that there has been toxoplasmosis contamination in Surabaya with evidence of 31% in serology and active infection with 19% tissue cyst. It is necessary for controlling with surveillance in cats to prevent transmission in humans. [ABSTRACT FROM AUTHOR]

Toxoplasmosis is a zoonotic disease of economic importance found worldwide, and it is caused by Toxoplasma gondii, which affects a wide range of hosts. High prevalence of toxoplasmosis has been reported in rodents, and they are considered very important in the circulation and maintenance of the disease. However, epidemiologic studies of the disease in rodents are generally scarce in the Tropics. This study utilized the immunohistochemical (IHC) technique to detect Toxoplasma gondii in wild rats sampled from across the North Central Nigeria. The brain, intestine, diaphragm, lungs and kidney tissue samples from 227 wild rats (Zyzomys pedunculatus) were routinely processed for histopathology, out of which 86 were further selected for IHC detection of T. gondii antigens using the streptavidin-peroxidase method. The histologic lesions observed were mild to moderate in severity, including meningitis, focal gliosis, neuronal degeneration and necrosis, villous atrophy and denudation, enteritis, diaphragmatic myositis, broncho-interstitial pneumonia and interstitial nephritis. Toxoplasma gondii was detected in 82.6% of the selected samples showing various degrees of immunoreaction intensity. We conclude that IHC is a useful tool in the detection of T. gondii in wild rats, and lungs and kidney may be the organ of choice for the detection of T. gondii. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii is a worldwide distributed zoonotic pathogen that threatens public health. However, there have been limited data for T. gondii infection in wild rats (Rattus norvegicus) in China. In the present study, a total of 227 wild rats were captured from three mink farms to investigate T. gondii infection in Shandong Province, eastern China. The DNA was extracted from 25 mg rats' brain tissues and subjected to a PCR amplification by targeting to the T. gondii B1. In 227 wild rat samples, 18 samples (7.93%) were positive for T. gondii. Then, the positive samples were further genotyped based on eight genetic markers, including eight nuclear loci (SAG1, 5′-SAG2, and 3′-SAG2, alternative SAG2, SAG3, GRA6, c29–2, and L358) and an apicoplast locus (Apico) by using the multilocus PCR-restriction fragment length polymorphism technology. Of these samples, eight were genotyped at nine nuclear loci, and two were genotyped at eight nuclear loci, forming three known genotypes (ToxoDB no. 43, ToxoDB no. 91, and ToxoDB no. 189) and two new genotypes. The closest ToxoDB genotypes were observed in wild rats, suggesting the differences in the population structure of the T. gondii between breed farm animals and wild rats. These data revealed the genetic variability of T. gondii in wild rats on mink farms in Shandong Province, with possible implication for public health. [ABSTRACT FROM AUTHOR]

Enterocytozoon (E.) bieneusi and Cryptosporidium spp. are the most important zoonotic enteric pathogens associated with diarrheal diseases in animals and humans. However, it is still not known whether E. bieneusi and Cryptosporidium spp. are carried by wild rodents in Shanxi, Guangxi, Zhejiang, Shandong, and Inner Mongolia, China. In the present study, a total of 536 feces samples were collected from Rattus (R.) norvegicus , Mus musculus , Spermophilus (S.) dauricus , and Lasiopodomys brandti in six provinces of China, and were detected by PCR amplification of the SSU rRNA gene of Cryptosporidium spp. and ITS gene of E. bieneusi from June 2017 to November 2020. Among 536 wild rodents, 62 (11.6%) and 18 (3.4%) samples were detected as E. bieneusi - and Cryptosporidium spp.-positive, respectively. Differential prevalence rates of E. bieneusi and Cryptosporidium spp. were found in different regions. E. bieneusi was more prevalent in R. norvegicus , whereas Cryptosporidium spp. was more frequently identified in S. dauricus. Sequence analysis indicated that three known Cryptosporidium species/genotypes (Cryptosporidium viatorum , Cryptosporidium felis , and Cryptosporidium sp. rat genotype II/III) and two uncertain Cryptosporidium species (Cryptosporidium sp. novel1 and Cryptosporidium sp. novel2) were present in the investigated wild rodents. Meanwhile, 5 known E. bieneusi genotypes (XJP-II, EbpC, EbpA, D, and NCF7) and 11 novel E. bieneusi genotypes (ZJR1 to ZJR7, GXM1, HLJC1, HLJC2, and SDR1) were also observed. This is the first report for existence of E. bieneusi and Cryptosporidium spp. in wild rodents in Shanxi, Guangxi, Zhejiang, and Shandong, China. The present study also demonstrated the existence of E. bieneusi and Cryptosporidium spp. in S. dauricus worldwide for the first time. This study not only provided the basic data for the distribution of E. bieneusi and Cryptosporidium genotypes/species, but also expanded the host range of the two parasites. Moreover, the zoonotic E. bieneusi and Cryptosporidium species/genotypes were identified in the present study, suggesting wild rodents are a potential source of human infections. [ABSTRACT FROM AUTHOR]

Enterocytozoon bieneusi is an opportunistic pathogen in immunodeficient patients. Although this pathogen has been reported in many domestic animals, few data are available about the occurrence of E. bieneusi in wild rats. In the current study, a total of 228 fecal samples from two wild rat species (Leopoldamys edwardsi and Berylmys bowersi) in China were examined by a nested PCR-based sequencing approach employing the internal transcribed spacer (ITS) region of nuclear ribosomal DNA. The overall prevalence of E. bieneusi in wild rats was 33.3% (76/228), with 35.1% (39/111) in L. edwardsi and 31.6% (37/117) in B. bowersi. Ten E. bieneusi genotypes (including four known and six novel genotypes) were identified, with the novel CQR-2 (n = 15) as the predominant genotype. Phylogenetic analysis indicated that ten genotypes in the present study belong to zoonotic group 1, which contains many genotypes in humans. Furthermore, multilocus sequence typing (MLST) analysis showed that 19 ITS-positive samples were successfully amplified at three microsatellites and one minisatellite, forming 18 multilocus genotypes (MLGs). This is the first report of E. bieneusi infection in the wild rats L. edwardsi and B. bowersi. Our findings suggest that wild rats could be a significant source of human infection, including contaminated food and water. [ABSTRACT FROM AUTHOR]

Background: Cryptosporidium viatorum is a minor Cryptosporidium pathogen in humans. Currently, there is limited information regarding the prevalence and genotypes of C. viatorum in animals in China. Methods: In this study, 228 faecal samples were collected from two wild rat species (Leopoldamys edwardsi and Berylmys bowersi) in Chongqing Municipality and Guangdong Province, China. These specimens were analyzed for C. viatorum and then subtyped it using PCR and sequence analysis of the small subunit ribosomal RNA (SSU rRNA) and 60-kilodalton glycoprotein (gp60) genes, respectively. Results: A total of 25 (11.0%) faecal samples were tested positive for C. viatorum by SSU rRNA assay. Of these samples, 4 (3.6%) came from L. edwardsi and 21 (18.0%) from B. bowersi. Of the 25 C. viatorum-positive samples, 17 were successfully amplified at the gp60 gene locus, which represented four subtypes belonging to two subtype families, including XVa (XVaA6, XVaA3g, XVaA3h) and XVc (XVcA2G1). Phylogenetic analysis based on the gp60 amino acid sequences indicated that all of the C. viatorum isolates grouped together, supporting the conclusion that C. viatorum from the wild rats represent two subtype families. Conclusions: These results indicate an occurrence of C. viatorum XVa subtype family from rats which is genetically identical to those found in humans. Our findings suggest that wild rats may be a potential source of human cryptosporidiosis. [ABSTRACT FROM AUTHOR]

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The helminthes may act as indicators of pollution of the environment where their hosts live. The present study was conducted to evaluate the role of cestodes in the elimination of some toxic minerals such as cadimum (Cd) and chrome (Cr) in wild rats (Rattus norvegicus) which has been used as a model. The results showed that there are high concentrations of Cd and Cr in kidneys and livers compared to intestines and muscles of captured rats from industrial and agricultural areas in Diyala Province. The concentrations of both Cd and Cr were significantly higher (P< 0.05) in the cestodes than in the rat tissues. The bioaccumulation factor for Cd increased 3.2 folds and 2.1 folds in the worms than in the intestines and muscles of the rats, respectively in agricultural areas and 2.8 folds and 1.4-fold in worms than in the intestines and muscles of rats captured the in industrial areas. For Cr, the bioaccumulation factor increased 3.1 folds and 2.8 folds in worms than in the intestines and muscles of rats from the agricultural areas while it increased 2.7 folds and 1.4-fold in worms than in the intestines and muscles in the industrial areas. In conclusion, and in comparison, between infected and non-infected rats and the bioaccumulation factors in the present study, it is possible to propose the ability of the cestode (Hymenolepis diminuta) to absorb some toxic elements such as Cd and Cr from their hosts. [ABSTRACT FROM AUTHOR]

Pneumocystis pneumonia is a disease caused by Pneumocystis jiroveci or and Pneumocystis carinii. It is more commonly observed in patients with immune deficiency that causes inflammation and obstruction of the lungs. This study focused on the molecular detection of P. jiroveci in wild rats living in southwest of Iran. In this study, 100 lung tissue samples were collected from wild rats in Ahwaz. After staining through Giemsa and microscopic examination, DNA extraction was performed. Then, the Nested-PCR (Polymerase Chain Reaction) was conducted for detection. Finally, the results were analyzed by chi-square test. Of the 100 lung tissues, 32 were infected with P. jiroveci. Moreover, 27 were from the Rattus norvegicus species and 5 were Rattus rattus infected with pneumocystis, where the prevalence of the two species were identical (P-value = .597). In terms of gender, 17 were male and 15 were female, and the infection rates were identical in both (P-value = .798). The Nested-PCR is a reliable method for the detection of P. jiroveci. This was the first report from Iran's southwest where great populations of rats (32%) were affected by P. jiroveci. Due to the transmission of different diseases from rats to humans, these diseases in rats can pose a dangerous threat to human health, particularly people with immune deficiency, AIDS and children. [ABSTRACT FROM AUTHOR]

Cysticercus fasciolaris, the larval form of Taenia taeniaeformis, is commonly encountered in rodents. In our study, 287 wild rats (Rattus norvegicus) in South Korea were examined in 2010 and 2011. Of 287 rats, 97 (33.8%) were infected with C. fasciolaris. A strong positive correlation was found between the host body weight and prevalence in both sexes, regardless of the year of collection. The liver was the most common habitat of the parasite, and the lung was the most frequent ectopic region, followed by mesentery, pleura, abdominal wall, and kidney. The lesions of the affected organs were generally characterized by well-developed cysts, each containing a larva. However, the cysts within kidney and abdominal wall were poorly organized, filled with abscess, and lacked larvae. Collagen types I and III, but not type IV, played significant roles in constructing the cysts at differential stages, addressed by immunohistochemistry. During cyst wall development, both collagen types contributed equally to cyst formation at the early stage, whereas collagen type I was the major component at the late stage (p < 0.05). In early-stage cysts, distribution of collagens was interestingly differential depending on the development stage, as collagen type I was localized in the outer layer and type III was located in the inner layer. Our results suggest that an appropriate remodeling process of collagen fibers is necessary for C. fasciolaris to build the well-conditioned cysts in the target organs for survival. [ABSTRACT FROM AUTHOR]

Bufavirus (BuV) was first discovered from feces of children with acute diarrhea. It was subsequently detected from several animal species including shrews, bats, and nonhuman primates. In this study, we identified a novel Protoparvovirus, designated RatBuV, from the intestinal contents of wild rats using viral metagenomics. The near complete genome was 4643 nt encoding NS1, VP1, and VP2 proteins. Phylogenetic analysis over the complete genome showed that RatBuV clustered with Mpulungu BuV from shrews. Sequence analysis indicated that the putative protein sequences of NS1, VP1, and VP2 of RatBuV shared identities of 50.6-77.2, 48.3-77.3, and 47.1-78.3 %, respectively, with those of human BuVs, MpBuV, and WUHARV parvovirus, suggesting RatBuV belongs to a new species of Protoparvovirus. Our epidemiologic study indicated that the prevalence rate of RatBuV in the cohort of 40 wild rats is 12.5 % (5/40), which is higher than that of BuV in humans in a previous study. [ABSTRACT FROM AUTHOR]

Rickettsioses are emerging zoonotic diseases reported worldwide. In spite of the serological evidence of spotted fever group rickettsioses in febrile patients in Malaysia, limited studies have been conducted to identify the animal reservoirs and vectors of rickettsioses. This study investigated the presence of rickettsiae in the tissue homogenates of 95 wild rats and 589 animal ectoparasites. Using PCR assays targeting the citrate synthase gene (gltA), rickettsial DNA was detected in the tissue homogenates of 13 (13.7%) wild rats. Sequence analysis of the gltA amplicons showed 98.6–100% similarity with those of Rickettsia honei/R. conorii/R. raoultii (Rickettsiales:Rickettsiaceae). Sequence analysis of outer membrane protein A gene (ompA) identified Rickettsia sp. TCM1 strain from two rats. No rickettsia was detected from Laelaps mites, Rhipicephalus sanguineus and Haemaphysalis bispinosa ticks, and Felicola subrostratus lice in this study. R. felis was identified from 32.2% of 177 Ctenocephalides felis fleas. Sequence analysis of the gltA amplicons revealed two genotypes of R. felis(Rf31 and RF2125) in the fleas. As wild rats and cat fleas play an important role in the enzoonotic maintenance of rickettsiae, control of rodent and flea populations may be able to reduce transmission of rickettsioses in the local setting. [ABSTRACT FROM AUTHOR]

The prevalence of antibodies against spotted fever group rickettsia (SFGR), murine typhus and Q fever were investigated in wild rats captured in Indonesia. Sera of 327 rats were collected from Jakarta and Boyolali on Java Island. The prevalences of antibodies against SFGR and murine typhus were 128 (39.1%) and 48 (14.7%), respectively. Antibodies against Q fever were not detected in these serum samples. Antibodies against SFGR were found in all species of rats (20.8–51.9%). The antibody positive rate against murine typhus in Rattus norvegicus (38.0%) was significantly higher than that in other rat species (0–4.8%, p < 0.01). The antibody positive rates against SFGR and murine typhus in rats captured in Jakarta were significantly higher than those in rats captured in Boyolali (p < 0.01). In this survey, all species of rats had antibodies against SFGR, indicating that the 4 species of tested rats (R. norvegicus, R. rattus, R. exulans, R. tiomanicus) were infected with SFGR and that SFGR may infest the whole of Java Island. Most of the rats that were antibody-positive against murine typhus were captured in Jakarta. Therefore, R. norvegicus and R. rattus are likely to be important hosts of murine typhus in Jakarta. The antibody-positive rates against SFGR and murine typhus in rats captured in the dry season were significantly higher than those in rats captured in the rainy season. This may coincide with the active periods of ticks and fleas in Indonesia. [ABSTRACT FROM AUTHOR]

Wild rats, Rattus norvegicus, (a) trapped as adults or (b) of the second generation in captivity (lab-wild), and domestic rats of two strains, were studied for 28 days in artificial colonies in large cages with attached nest boxes. Controls were kept in mated pairs in small cages. Each colony consisted of six males and six females. The interactions of the males in six colonies of trapped rats were highly "stressful;" 61% died; and most of the survivors lost weight and had greatly enlarged adrenals. In each colony, however, there was a male (an alpha) that gained in weight and spent much time, during the dark hours, in the open on the floor of the cage; and in three colonies there were also other males ("betas") that gained in weight. The adrenals of alphas and betas weighed about the same as those of the controls. In one of the 12 colonies of domestic rats one male behaved like a wild male; but in the other colonies the males gained in body weight and their adrenal weights resembled those of the controls. In three colonies of lab-wild rats 22% of the males died, but there was no evidence of males of different status. The findings confirm that the "agonistic" behavior of domestic rats is usually much attenuated in comparison with that of the wild type; a number of methodologic implications are discussed. [ABSTRACT FROM AUTHOR]