Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “RODENTS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 217 records · Page 12Linked to original sources
PubMed2001

Development and validation of an ELISA for the detection of leptospire-specific antibodies in rodents.

An enzyme-linked immunosorbent assay (ELISA) for the detection of IgG antibodies in rodents was developed and validated with the microscopic agglutination test (MAT) and leptospiral cultures. Sonicated antigen from cultures of serovars tarassovi and pyrogenes was used. As conjugate, a combination of anti-rat and anti-hamster IgG labeled with peroxidase was used. The optimal cut-off point was determined by plotting the sensitivity and specificity for various cut-off point values by means of receiver operating characteristic (ROC) curve. Concordance between ELISA and each of the MAT titers was measured by kappa (kappa). Proportions of positive results were compared by means of McNemar's test. Total 214 rodents were trapped, but only 117 could be processed by the three techniques (culture, ELISA, MAT; 1:20, 1:40, 1:50) and used for statistical analysis. Although, MAT titers in rodents infected with the serogroup Ballum tended to be lower than those infected with the serogroup Icterohaemorrhagiae, all (20/20) were ELISA-positive and almost all (19/20) were MAT-positive.The percentage of positive results obtained by ELISA, 47.0% exceeded significantly the 40.2% obtained by MAT (1:50). Difference between ELISA and MAT (1:40) was not significant and no differences were observed between ELISA and MAT (1:20). Agreement, specificity, sensitivity and the consequent area under the ROC curve between ELISA and MAT were higher as MAT cut-off points were lowered, being optimal at 1:20. The fact that differences between ELISA and MAT were significant at 1:50, but not at 1:40 or 1:20, supports the suggestion that lower MAT titers should be considered positive in rodents. The ELISA developed to detect leptospire-specific antibodies had optimal sensitivity and specificity in relation to MAT and it is concluded that it may constitute a very useful indicator for epidemiological purposes of past or present leptospiral infection in rodents.

Agglutination Tests↗
PubMedDate not supplied

Detection, eradication, and research implications of Helicobacter infections in laboratory rodents.

Researchers first isolated and characterized Helicobacter hepaticus in 1994 as a cause of hepatitis that progressed to hepatocellular carcinoma in A/JCr mice. During the past decade, isolation and characterization of additional novel helicobacters from rodents has continued. In addition to causing overt disease, rodent helicobacter infections are important because intercurrent disease in select models will confound research data. Emerging evidence suggests that inflammatory responses to enterohepatic helicobacter infections may alter host responses to other experimental stimuli in unanticipated ways. Additionally, scientists have experimentally infected a variety of inbred mouse strains and genetically engineered mice with a variety of Helicobacter spp. isolated from rodents, birds, and higher mammals (including humans) to develop animal models of gastrointestinal diseases as well as idiopathic human disease syndromes. This review highlights current information about helicobacter infections in laboratory rodents and provides recommendations for the detection and eradication of these infections. The authors discuss the impact of subclinical and clinical disease and offer recommendations for managing helicobacter-free rodent colonies.

Animals↗
PubMed2005

Rodent-associated Bartonella in Saskatchewan, Canada.

Six species of wild rodents were sampled at 10 sites in 2002 and 2003 to determine the prevalence of Bartonella infections in rodent communities near Saskatoon, Saskatchewan, Canada. Isolates were characterized genotypically and compared with isolates found at other locations. Of 104 wild rodents examined, 57% were infected with Bartonella and prevalence within species varied from 49% for Richardson's ground squirrels (Spermophilus richardsonii) to 90% for Franklin's ground squirrels (S. franklinii). Infected rodents were found at all sites. Sequencing of a 379-bp portion of the citrate synthase gene was performed on 54 isolates and revealed 13 distinct genotypes, eight of which had not been described previously. The most common genotype detected in red-backed voles (Clethrionomys gapperi) was 99.1% similar to B. grahamii, a known human pathogen. Two of 10 Franklin's ground squirrels were concurrently infected with multiple Bartonella genotypes. All genotypes, with the exception of one detected in both Franklin's and thirteen-lined ground squirrels (S. tridecemlineatus), were found in only one host, and all genotypes from each species, with the exception of genotypes detected in red-backed voles, clustered together within the same relatedness group, suggesting that at least some Bartonella genotypes are specific to some rodent hosts.

Animals↗
PubMed1976

Oral rabies vaccine: evaluation of its infectivity in three species of rodents.

The safety of oral rabies vaccine was evaluated in 3 species of rodents, animals which might inadvertently consume field-distributed vaccine baits intended for foxes. The potentials for infection from bait ingestion and transmission through cannibalism were evaluated. Results indicate that ingestion of the vaccine baits used in these experiments will result in infection and disease of some rodents. Of 64 rodents which ate baits, 19 (30%) died of clinical rabies; the diagnosis was confirmed in 11 (17%), and 2 (3%) had demonstrable rabies virus in their salivary glands. Only 3 of 112 (3%) rodents that ate vaccine-infected rodents contracted rabies, and none had demonstrable virus in their salivary glands.

Administration, Oral↗
PubMed2006

Molecular identification of Ehrlichia species and 'Candidatus Neoehrlichia mikurensis' from ticks and wild rodents in Shizuoka and Nagano Prefectures, Japan.

A total of 293 ticks and 111 wild rodents that were collected in Shizuoka and Nagano Prefectures, Japan, were examined for infection of Ehrlichia species and 'Candidatus Neoehrlichia mikurensis.' The 16S rDNA or the omp-1 gene of these bacterial DNAs were detected from the spleens of tick-inoculated mice (5 positive/total 29 mice) or from the spleens of wild rodents (25 positive/total 111 rodents) by PCR amplifi-cation. Sequencing of the 16S rDNA revealed Ehrlichia spp. from the 5 tick-inoculated mice and 8 wild rodents, and 'Candidatus N. mikurensis' from 17 wild rodents. The data suggest the presence of additional genetic variants, and potential vectors and/or reservoirs for these bacteria in central Japan.

Anaplasmataceae↗
PubMed1994

Infectivity and pathogenicity of Yersinia enterocolitica serovar 0:8 to wild rodents in Japan.

Three species of wild rodents, Anderson's red-backed voles (Eothenomys andersoni), large Japanese field mice (Apodemus speciosus) and small Japanese field mice (Apodemus argenteus), mainly living in mountainous areas in Japan, were challenged orally with Yersinia enterocolitica serovar 0:8 to determine infectivity and pathogenicity of this micro-organism with respect to wild rodents. Y. enterocolitica 0:8 was shown to colonize the intestinal tract of these three types of wild rodents, and was occasionally fatal. The faecal excretion period of these mice was 10-14 days in E. andersoni and A. speciosus, and 35-49 days in A. argenteus. Wild rodents recovering from the infection showed resistance to a second challenge with the same infectious agent. These results suggest that these three species of wild rodents living in mountainous areas in Japan may play an important role in the ecology of Y. enterocolitica 0:8.

Animals↗
PubMed2001

Host associations of ticks parasitizing rodents at Borrelia burgdorferi enzootic sites in South Carolina.

A total of 237 rodents was collected in 4 regions of South Carolina from July 1994 through December 1995. Eight species were collected, including cotton mouse, hispid cotton rat, eastern woodrat, marsh rice rat, white-footed mouse, eastern harvest mouse, golden mouse, and black rat. Of the 1,514 ticks recovered from these hosts, Ixodes minor Neumann, including larvae, nymphs, and adults, was the most abundant species, representing 54% of the total. Only immature stages of other tick species were found, including larvae and nymphs of Dermacentor variabilis (Say), Amblyomma maculatum Koch, Ixodes affinis Neumann, and Ixodes scapularis Say. All 5 tick species parasitized cotton mice, cotton rats, and woodrats, which were the most important small mammal hosts for ticks at the localities studied. Rice rats were hosts of A. maculatum, D. variabilis, and L. minor. Amblyomma maculatum was more strongly associated with cotton rats than other rodent species. Ixodes scapularis was most strongly associated with cotton mice, and I. minor was more strongly associated with both woodrats and cotton mice than other species of rodents. Ixodes minor parasitized hosts in the Coastal Zone only, where among spirochete-infected hosts, it was present in significantly greater numbers than other ticks. Furthermore, I. minor was the only tick species that showed a statistically significant positive association with spirochetal infection in rodents. More I. affinis parasitized spirochete-infected hosts than I. scapularis, but fewer than I. minor. The findings discussed herein provide evidence that implicates I. minor as the possible primary enzootic vector of the Lyme disease spirochete Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt and Brenner in the Coastal Zone of South Carolina. They also indicate that the high level of B. burgdorferi infection in rodents from this region may be a function of the combined involvement of I. minor, I. affinis, and I. scapularis in the enzootic transmission of the spirochete.

Animals↗
PubMed1992

A longitudinal study of Junin virus activity in the rodent reservoir of Argentine hemorrhagic fever.

We monitored Junin virus (JV) activity in rodent populations for 30 months at seven mark-recapture grids located in agricultural fields and adjacent roadsides and fence lines in endemic and nonendemic areas of Argentine hemorrhagic fever. Blood and oral swabs taken from rodents captured at five-week intervals were analyzed by enzyme-linked immunosorbent assay for JV antigen (Ag). Calomys laucha and C. musculinus were the most frequently captured rodents, making up 47% and 22% of captures, respectively. Of 41 Ag-positive captures, 37 were C. musculinus and four were C. laucha; 34 were from two trapping grids in the same locality. Antigen-positive Calomys were more frequently male (76%), and were found significantly more frequently among the oldest animals and the largest body mass classes. These patterns, combined with the greater mobility and higher frequencies of wounds among males than females, implicated horizontal transmission as the primary route of JV transmission between rodents. Seasonal maximum levels in JV prevalence (up to 25% of captured Ag-positive C. musculinus) occurred during periods of maximal population densities of Calomys. Spatial distribution of Ag-positive rodents reflected habitat preferences; most Ag-positive C. musculinus were captured from border habitats (roadsides and fence lines), and all Ag-positive C. laucha were captured in crop fields. These distinct, but previously undocumented, habitat preferences suggest that the disease in humans may be related to exposures to the primary reservoir species, C. musculinus, in border habitats rather than in crop fields.

Age Factors↗
PubMed1998

Short report: Decrease in seroprevalence of antibodies to hantavirus in rodents from 1993-1994 hantavirus pulmonary syndrome case sites.

Rodent trapping was conducted at seven hantavirus pulmonary syndrome (HPS) case sites from June 1993 to March 1994 during the HPS outbreak in the southwestern United States. To determine if there were changes in the rodent population or the hantavirus seroprevalence in rodents since the HPS outbreak, rodents were trapped at the same sites three years later using the same trapping protocol. The trap success decreased from the numbers trapped during the outbreak, however, the number of Peromyscus, as a percentage of the total rodents captured, did not noticeably decrease. In addition, the seroprevalence of hantavirus antibodies in Peromyscus decreased significantly (P < 0.0001).

Animals↗
PubMed2003

Rapid and simple method for screening wild rodents for antibodies to Sin Nombre hantavirus.

Sin Nombre hantavirus (SNV) is the primary etiologic agent of hantavirus cardiopulmonary syndrome (HCPS) in the United States and Canada. Hantavirus cardiopulmonary syndrome is a zoonotic disease. The most common reservoir is the deer mouse (Peromyscus maniculatus), although numerous other species of wild rodent can carry the viruses that cause HCPS throughout the Americas. Infected rodents show no signs of clinical disease but they develop persistent infection. Sin Nombre virus can be contracted by exposure to feces, urine, or saliva of its rodent reservoirs. Detection of infection in rodents is most often based upon detection of specific antibodies; many laboratories use enzyme linked immunosorbent assays (ELISAs), which require a specialized electrical ELISA reader. Enzyme linked immunosorbent assay readers are not readily amenable to field usage. We describe a portable test, the strip immunoblot assay (SIA), which we have utilized in field diagnosis. The test can be conducted in approximately 6 hr during the day or can be conducted overnight. The test can be used to detect rodents positive for SNV antibody while they are in traps. We show that results with the SIA have excellent concordance with western blot and reverse transcriptase polymerase chain reaction tests.

Animals↗
PubMed1975

Problems of rodent control in rural tropical areas.

Rodent control strategies, techniques, and research needs in rural tropical environments are reviewed and discussed with special reference to Mastomys natalensis, the possible reservoir of Lassa fever in West Africa.Public health rodent problems are far more serious and widespread in rural tropical areas than in developed countries. In the latter, only the commensal rodents constitute a major problem, whereas in rural tropical areas, native semidomestic species also serve as disease reservoirs and sources of infection to man. The success of rodent control programmes in developed countries depends in large part on the willingness and ability of people and governments to spend relatively large sums on research and control, on an acquired intolerance of people to rats and disease, and on a substantial economic base. These prerequisites are not usually to be found in rural tropical areas. Consequently, the rodent control techniques and programme organizations of developed countries are not directly applicable to such areas, even though the principles are the same. For this reason, it is suggested that a well-funded, integrated research and control programme should be undertaken in a known Lassa fever area, stressing public education, personnel training, and environmental management as well as rodenticidal approaches.

Africa, Western↗
PubMed1975

Problems associated with the control of rodents in tropical Africa.

As elsewhere in the world, rodents are responsible for very considerable economic losses in tropical Africa because of their depredations on both growing crops and stored food products. Unfortunately, few accurate data are available on the extent of these losses but there is evidence that they are considerable. The public health importance of rodents, both as reservoirs and vectors of disease in tropical Africa, is also great; plague, leptospirosis, murine typhus, and Lassa fever are among the diseases associated with rodent hosts. Scientifically based rodent control programmes have been carried out in very few areas of Africa and there is urgent need for studies and demonstrations on rodent control in both urban and rural areas. The problems likely to be encountered are reviewed and methods of control proposed.

Africa↗
PubMed2002

Detection of rodent coronaviruses by use of fluorogenic reverse transcriptase-polymerase chain reaction analysis.

Reverse transcriptase-polymerase chain reaction (RT-PCR) assays have proved useful for the detection of mouse hepatitis virus (MHV) and rat coronavirus (RCV) in acutely infected animals and contaminated biomaterials. Fluorogenic nuclease RT-PCR assays combine RT-PCR with an internal fluorogenic hybridization probe, thereby eliminating post-PCR processing and potentially enhancing specificity. Consequently, a fluorogenic nuclease RT-PCR assay specific for rodent coronaviruses was developed. Primer and probe sequences were selected from the viral genome segment that encodes the membrane (M) protein that is highly conserved among rodent coronaviruses. Use of the fluorogenic nuclease RT-PCR detected all strains of MHV and RCV that were evaluated, but did not detect other RNA viruses that naturally infect rodents. Use of the assay detected as little as two femtograms of in vitro transcribed RNA generated from cloned amplicon, and when compared directly with mouse antibody production tests, had similar sensitivity at detecting MHV-A59 in infected cell culture lysates. Finally, use of the assay detected coronavirus RNA in tissues, cage swipes, and feces obtained from mice experimentally infected with MHV, and in tissues and cage swipes obtained from rats naturally infected with RCV. These results indicate that the fluorogenic nuclease RT-PCR assay should provide a potentially high-throughput, PCR-based method to detect rodent coronaviruses in infected rodents and contaminated biological materials.

Animals↗
PubMed1992

[A study on transmission of epidemic hemorrhagic fever virus through skin wounds among rodents in natural conditions].

224 rodents captured from endemic areas of epidemic hemorrhagic fever (EHF) in Hubei province were examined for the presence of skin wounds and EHF viral antigens and antibodies by immunofluorescent assay (IFA) technique. It was found that 30.8% (69/224) of the captured rodents had skin wounds and that 24.6% (17/69) and 29.0% (20/69) of the wounded rodents were positive respectively to EHF viral antigens and antibodies, as compared with the corresponding rates of 9.0% (14/155) and 8.4% (13/155) in rodents without skin wounds. This suggests that infection through skin wounds could be an important route of transmission of the EHF virus among rodents under natural conditions.

Animals↗
PubMed2006

[Investigation on hantaviruses infection in rodents from free markets in Beijing areas].

OBJECTIVE: In order to find out the factors related to hemorrhagic fever with renal syndrome (HFRS) infection, and to evaluate the probability of ecdemic hantaviruses (HV) infection in rodents in Beijing areas. METHODS: Rodents were collected in a large-scale railway station and a produce market with 'trap nights' method from April to May, 2004. The IgG reacting sera to HV antigen were detected using ELISA. The partial M and S segment of HV from captured rodent lung samples were amplified with RT-PCR. The PCR products were purified and sequenced. BLAST program was then used to perform on nucleotide pairwise alignment with all available sequence in GenBank. The alignment of the multiply nucleotide and the deduced amino acid sequences, together with phylogenetic analysis were completed with DNASTAR software. RESULTS: The average population density was 3.49% (24/690). The overall seroprevalence of HV infection was 8.3% (2/24). RT-PCR positive rates were 8.3% (2/24). The nucleotide sequences of 356 bp region (1958 - 2313) of M segment obtained from 2 samples were all identified to Seoul virus (SEOV), with 7.6% heterogeneity. The dc501 strain from railway station was closely related to SD227 and Hebei4 from Shandong and Hebei provinces respectively. BjFT01 strain from the farm product market had more special nucleotide transitional mutations than other known SEOV from Beijing in GenBank. This strain, together with known HN71 from Hainan province, K24-E7 from Zhejiang province, L99 from Jiangxi province and R22 from Henan province, represented a monophylogentic linkage. CONCLUSION: The higher HV prevalence of rodents in transportation center was the potential and important risk for HFRS epidemic in Beijing. The increasing prevalence of M. musculus should call for attention. It was possible that SEOV in Beijing was imported by infected rodents through vehicles from other provinces.

Animals↗
PubMed2006

[First serological evidence of Hantavirus infection in rodents in Colombia].

OBJECTIVE: Determining Hantavirus infection prevalence in rodents in the C6rdoba department, Colombia. METHODS: Rodents were captured using Sherman live-capture traps (8 x 9 x 23 cm; Sherman Traps, Inc., Tallahassee, FL) in peridomestic areas of Córdoba. Hantavirus IgG antibodies were detected by ELISA using Sin Nombre virus (SNV) recombinant nucleocapsid antigen (CDC, Atlanta, Georgia, USA). RESULTS: 336 rodents were captured in 11 townships in the Córdoba department (Murinae: 249; Sigmodontinae: 68; Heteromyidae: 17; Echimyidae: 2; 8.5% overall trap success) during 79 nights of trapping between January 2003 and November 2004. Hantavirus antibody seroprevalence was 2.1% (7 out of 336 captures). Prevalence by genus varied between 5.9% (1 out of 17 Heteromys) to 50% (1 out of 2 Proechimys). CONCLUSIONS: SNV-reactive antibody prevalence in rodents in Córdoba, Colombia, indicated that at least one hantavirus is endemic in rodents in northern Colombia and is frequently transmitted to rural residents.

Animals↗
PubMed1991

New host and locality records of coccidia (Apicomplexa: Eimeriidae) from rodents in the southwestern and western United States.

One hundred forty-seven murid and heteromyid rodents were collected from various sites in the southwestern and western United States (Arizona, Colorado, New Mexico, Texas, and Utah) and Baja California Norte, Mexico, and their feces were examined for coccidial parasites. Of these, 53 (36%) were infected with at least 1 coccidian; 45 of 53 (85%) of the infected rodents harbored only 1 species of coccidian. Infected rodents included: 10 of 22 (45%) Neotoma albigula, 3 of 11 (27%) Neotoma floridana, 2 of 14 (14%) Neotoma lepida, 15 of 29 (52%) Neotoma micropus, 5 of 8 (63%) Peromyscus crinitis, 6 of 6 (100%) Peromyscus difficilis, 1 of 2 (50%) Peromyscus eremicus, 9 of 34 (26%) Sigmodon hispidis, and 2 of 3 (67%) Sigmodon ochrognathus; 4 Neotoma cinerea, 3 Neotoma devia, 3 Neotoma mexicana, 1 Peromyscus maniculatus, 1 Onychomys leucogaster, 1 Onychomys torridus, 3 Chaetodipus fallax, and 2 Chaetodipus penicillatus were negative. Although no new species was found, the following coccidians were identified from infected rodents: Eimeria albigulae from N. albigula, N. floridana, and N. micropus, Eimeria antonellii from N. albigula and N. micropus, Eimeria ladronensis from N. albigula, N. floridana, N. lepida, and N. micropus, Eimeria arizonensis and Eimeria lachrymalis from P. crinitis and P. difficilis, Eimeria lachrymalis from P. eremicus, Eimeria tuskeegensis from S. ochrognathus, and Eimeria roperi, Eimeria sigmodontis, Eimeria tuskeegensis, Eimeria webbae, and an unidentified species of Eimeria from S. hispidis. This report documents 12 new host and several distributional records for Eimeria species from murid rodents in Arizona, Texas, and Utah.

Animals↗
PubMed1972

Public health importance of rodents in South America.

Indigenous South American rodents are abundant, varied, and adaptable, and occupy most of the available natural habitats. Knowledge of their taxonomy and biology is generally superficial. Near human habitations the introduced Rattus and Mus are common and their contacts with man are often close. Cities in South America are expanding to keep pace with increases in the human population and hitherto virgin land is being settled or cleared for food production. Thus domestic rodents are brought into contact with indigenous species and the inevitable exchange of parasites may then produce unpredictable threats to human health. The role of both wild and domestic rodents in the transmission of certain infectious diseases, such as plague, sylvatic Venezuelan encephalitis, South American haemorrhagic fevers, murine typhus, and cutaneous leishmaniasis, is well established. The involvement of rodents in some other diseases, such as leptospirosis, American trypanosomiasis, South American hydatid disease, and vesicular stomatitis, is less well understood. In certain other infections, including bartonellosis and the South American spotted fevers, a wild rodent reservoir is inferred but not yet identified.

Animals↗