Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “LEPTOSPIRA INFECTIONS”

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 451 records · Page 25Linked to original sources
PubMed1986

Experimental leptospirosis (L. interrogans serovar icterohaemorrhagiae) of the guinea pig: leptospiral antigen, gamma globulin and complement C3 detection in the kidney.

Morphofunctional and immunofluorescent studies were done in guinea pigs experimentally infected with Leptospira interrogans serovar icterohaemorrhagiae to determine the role of leptospiral antigen, gamma-globulin, and complement C3 deposits in the pathogenesis of the renal lesions. A sharp increase in leptospiral antigen deposits was observed in the late phase of the experimental infection. Immunoglobulin and complement C3 were small compared with the heavy leptospiral antigen deposits. Moreover, leptospiral antigen was observed mainly in the interstitium whereas immunoglobulin and complement C3 deposits were seen in glomeruli and small blood vessel walls. In our experimental model bacterial migration and local liberation of factors causing virulence seems more likely to determine the renal damage.

Animals↗
PubMed1989

Pathogenesis of renal lesions in haemoglobinaemic and non-haemoglobinaemic leptospirosis.

Hamsters were infected with Leptospira interrogans serovar ballum or Leptospira interrogans serovar pomona and the kidney lesions were compared by light and electron microscopy. Ballum and pomona both caused severe clinical signs and death within 6 days in some animals, although only ballum was associated with red blood cell destruction and haemoglobinaemic nephrosis. With ballum infections it is difficult to distinguish degenerate changes resulting from leptospiral "toxins" from those resulting from hypoxia and haemoglobinaemic nephrosis because large numbers of organisms and haemoglobinaemia coincide shortly before death. Although large numbers of leptospires were seen within the renal interstitium and blood vessels in animals dying shortly after infection, organisms were seen only in the proximal convoluted tubules of those surviving until 14 days. It is thought that leptospires are carried by the bloodstream and migrate at random throughout all body tissues. When antibody develops, only those in the renal tubules remain. The random migration results in some leptospires entering tubules at all levels of the nephron but there are good grounds for believing that the normal changes in composition of the glomerular filtrate as it passes through the nephron are increasingly deleterious to leptospiral survival. This probably explains why leptospires are found predominantly in the proximal convoluted tubules of animals after the development of specific immunity.

Animals↗
PubMed1987

Isolation of Leptospira hardjo from kidneys of Ontario cattle at slaughter.

Kidneys from 117 cattle from 110 Ontario farms were examined at slaughter for leptospires. Leptospira hardjo (hardjo-bovis A) was isolated from 11 kidneys and L. kennewicki from one. The isolations were all made (12/89, 13.5%) from beef cattle from feedlots, no isolates being obtained from dairy or beef cattle from extensive farms (0/28). Isolations were only made from cattle with antibody titers (greater than or equal to 20) against the serovars recovered. Isolation was more sensitive than immunofluorescence in identifying leptospira, particularly in animals with low antibody titers against L. hardjo. Leptospira were isolated from two kidneys with multiple gross lesions of focal nephritis, but there was no correlation between the presence of scanty kidney lesions and isolations of leptospira. Leptospira hardjo infection appears to be common in Ontario feedlot cattle.

Abattoirs↗
PubMed2005

Molecular detection of Leptospira kirschneri in tissues of a prematurely born foal.

Leptospirosis was identified to be the possible cause of premature birth in a foal on a farm with a history of repeated abortions. Using an appropriate polymerase chain reaction (PCR) assay, the presence of Leptospira kirschneri was detected in the tissues of the prematurely born foal. Further confirmation of L. kirschneri was obtained by nucleotide sequence analysis of the PCR-amplified DNA fragment and the partial 16S ribosomal RNA gene sequence. This report further supports mounting evidence that a PCR assay capable of detecting L. kirschneri should be included in routine diagnostic investigations in which Leptospira spp. infection is suspected.

Animals↗
PubMed1980

Maturation of humoral immune response determines the susceptibility of guinea-pigs to leptospirosis.

Baby guinea-pigs were susceptible to infection with Leptospira interrogans serovar pomona, but rapidly became resistant as they matured. Increased resistance with increasing weight of guinea-pigs was correlated with the development of ability to produce agglutinating antibodies to leptospires and with maturation of B-cell dependent (but not T-cell dependent) areas in lymphoid organs. These observations can explain the basis of species-resistance of adult guinea-pigs to infection with serovar pomona.

Aging↗
PubMed1994

Rapid and specific detection of pathogenic Leptospira species by amplification of ribosomal sequences.

We have developed an assay for the detection of pathogenic Leptospira that is based on the polymerase chain reaction. With the combination of agarose gel electrophoresis and blotting, pathogenic Leptospira can be discriminated specifically from nonpathogenic Leptospira and other bacterial species. This method, based on the amplification of 16S ribosomal RNA sequences, is able to detect 10 leptospiral cells/mL in cattle urine samples and 100 leptospiral cells/mL in pig urine samples. Using this assay leptospires were detected in urine samples from cattle that were experimentally infected with Leptospira interrogans serovar hardjo type hardjobovis.

Animals↗
PubMed1992

[The immunochemical and biological properties of Leptospira membranes].

The immunochemical and biological properties of purified membrane fractions obtained from Leptospira interrogans, serovar copenhageni, strain Rat 2, and Leptospira biflexa, strain Patoc 1, were studied. The presence of genus-specific and group-specific antigens in leptospiral membranes was established by the methods of immunodiffusion analysis, the microagglutination (MA) and lysis tests. In animal experiments cell membrane preparations produced no toxic and allergic effects. Leptospiral membranes obtained from strain Rat 2 ensured the protection of golden hamsters infected with Leptospira virulent culture and induced antibody production in high titers, detected with the use of the MA test, the lysis test and the enzyme immunoassay, in rabbits immunized in two injections.

Animals↗
PubMed1991

Prevalence of antibodies to five selected zoonosis agents in monkeys.

The prevalence of antibodies against 5 zoonosis agents was determined in serum samples of 443 breeding monkeys. Of the monkeys, 296 were bred or kept for a long time at R institute, and the remaining 147 were newly imported from the Philippines and kept at S institute for quarantine. Antibodies to simian virus 40 were highly prevalent at 89.1% among monkeys of R institute, whereas no antibody could be detected in those of S institute. Antibodies to Chlamydia psittaci and Yersinia pseudotuberculosis were detected in 14.4 and 11.6% at R institute, and in 9.0 and 3.5% at S institute, respectively, evidencing a significant difference (P less than 0.05) between those of the two institutes for both agents. Antibodies to Toxoplasma gondii and Leptospira interrogans were found in 3.6 and 2.9% of the overall, respectively, showing no difference in positive rates in relation to breeding place. Even in cases positive to the latter 4 zoonosis agents, the antibody titers were low. The results obtained suggest that all zoonoses tested do not seem to be so serious diseases among monkeys at the present time except simian virus 40 infection, which is highly prevalent among breeding monkeys in Japan.

Animals↗
PubMed2001

Herd-level risk factors associated with Leptospira spp. seroprevalence in dairy and beef cattle in Spain.

Our aim in this cross-sectional study was to investigate the seroprevalence of Leptospira spp. infection in herds and cattle and the relationships between seroprevalence and beef versus dairy, size, replacement policy and grazing management in a representative area of beef- and dairy-cattle production in Spain. Herds were the initial sampling unit. Blood samples were collected from 762 dairy cattle belonging to 81 herds and 1238 beef cattle from 134 herds; sera were tested for antibodies against 11 serovars of Leptospira (autumnalis, ballum, bratislava, canicola, castellonis, copenhagheni, grippotyphosa, hardjo, louisiana, pomona and tarassovi) using the microagglutination test. Forty-three percent (36.2-49.5%) of the herds and 8% (6.4-8.8%) of the individuals were seropositive against one or more of the serovars studied. Bratislava was the most-prevalent serovar (24% of the herds and 4% of the individuals) followed by hardjo (11 and 1%, respectively). Grippotyphosa, copenhagheni and tarassovi were more prevalent in dairy than in beef herds (P<0.001, P<0.05, P<0.05, respectively) -- but no significant association was found between herd-size and Leptospira seroprevalence for any of the serovars considered.

Animal Husbandry↗
PubMed1997

Seroepidemiology of canine leptospirosis on the island of Barbados.

Previous surveillance in Barbados documented the absence of infection with Leptospira serogroup Canicola in dogs. The aim of this study was to survey the current state of canine leptospirosis in Barbados, 10 years after the last survey. Sera from 78 unwanted dogs scheduled for euthanasia and 61 dogs suspected of having acute leptospirosis were tested by microscopic agglutination (MAT) and by an ELISA method adapted for canine IgM and IgG antibodies. The seroprevalence in unwanted dogs was 62% (48/78), at an MAT titre of > or = 100. The majority of animals had low titres, suggestive of previous infection. Serogroup Autumnalis was the most common reactor (45%), followed by serogroups Icterohaemorrhagiae and Australis (each 16%) and Pomona (13%). Serogroup Ballum was uncommon in this group. The seroprevalence determined by MAT in acutely-ill dogs was 75% (46/61). The most common predominant serogroup was Icterohaemorrhagiae (36%) followed by serogroup Australis (13%), while serogroups Autumnalis and Ballum were also of little significance. Paired specimens were available from eight acutely-ill dogs. One animal was seronegative while five dogs showed evidence of seroconversion. An IgM-ELISA titre of > or = 320 was used to confirm current infection in eight of these nine animals. Previous studies in Barbados showed a higher prevalence of serogroup Icterohaemorrhagiae than of Autumnalis, but the relative frequency of these two serogroups may be changing. The high seroprevalence in dogs is of public health concern because the close contact between dogs and man may provide the link between a reservoir in the environment and susceptible humans.

Acute Disease↗
PubMed2002

The use of chosen serological diagnostic methods in Lyme disease in horses. Part II. Western blot.

In this investigation the Western blot test was treated as a method verifying results of the IFA, commercial ELISA and standardized ELISA tests (described in Part I). The verifying investigations were performed on 82 serum samples, which in the commercial ELISA were positive in 36 cases, dubious in 31 cases and negative in 15 cases as well as on 5 serum samples obtained from horses infected with Leptospira spp., which in the ELISA commercial were dubious (total of 87 sera samples). The antigens, against which the immunological response in horses was directed, were also established. The Milenia--Blot--Borrelia IgG test (MIDBO IgG-Kit 30 TESTS: DPC Bierman GmbH) was used in the investigation. In view of species differences, rabbit anti-horse IgG (whole molecule) alkaline phosphatase conjugate, no A6063 SIGMA-ALDRICH was used interchangeably. Also the control sera were substituted with the horse control sera. It was demonstrated that the Western blot test is the most reliable in the serological diagnosis of B. burgdorferi infection in horses. The commercial ELISA and standardized ELISA tests represent a lower diagnostic value than the Western blot test, although similar to each other, while the value of the IFA is minimal. In the Western blot test antigens were established against which the immunological response in horses in mostly directed. In the sera evaluated in this test as positive the presence of antibodies, mainly against antigens with the following molecular weights: 41 kDa, 62/60 kDa, 93 kDa, 72 kDa, 34 kDa (OspB), 66 kDa was noted. At the same time, antibodies contained in the sera accepted as negative, in 55.5% cases also reacted with the antigen of 41 kDa. It points to its minimal specificity. On the basis of the results obtained it is recommended that serological examination of horses should be with the ELISA and that positive or dubious results should be verified with the Western blot test.

Animals↗
PubMed1979

[Susceptibility and sensitivity of the Siberian lemming and Middendorff's vole to leptospirae of the grippotyphosa serogroup].

Siberian lemmings and Middendorf's voles were found to be susceptible to infection caused by Leptospira of the Grippotyphosa serogroup after the intraperitoneal injection of Leptospira culture, the application of the culture or infected urine to the skin, as well as after Leptospira-carrying animals were placed together with the animals to be infected. The infectious sensitivity of these animals to Leptospira was not high: leptospiruria was observed for 1-3 weeks; in some of the voles leptospiruria was slightly pronounced, whereas other voles had a great number of Leptospira in urine. Antibodies appeared in the blood on day 5 after infection, and their titers increased till days 61-63. In no case could Leptospira be isolated from the kidneys of the animals killed on days 61-83 of the experiment.

Animals↗
PubMed2026

A systematic review and meta-analysis to estimate the global prevalence of leptospirosis in sheep.

Leptospirosis in sheep is a zoonotic concern considering sheep may act as potential reservoirs for Leptospira spp. infection to humans. This study aimed to estimate the pooled prevalence of leptospirosis in sheep worldwide. A comprehensive literature search was conducted across databases following PRISMA guidelines. Meta-analyses were performed using a random effect model in R software (version 4.3.1) to calculate pooled prevalence with 95% confidence intervals (CI). Subgroup analyses were performed based on prevalence types, diagnostic methods and continental regions to explore sources of heterogeneity. A total of 138 studies comprising 54,174 samples and 10,299 positive detections were included in this study. The global pooled prevalence of leptospirosis in sheep was 15.69% (95% CI: 12.69-19.25) with overall heterogeneity (I2) 98%. The prediction interval ranged from 1.09% to 75.91%, indicating wide inter-study variability. The seroprevalence was 16.16% (95% CI: 12.91-20.04) and infection prevalence was 12.98% (95% CI: 8.07-20.22), showing no significant difference (P&#xa0;=&#xa0;0.40). In addition, the prevalence of leptospirosis in sheep differed significantly across diagnostic methods and continents (P&#xa0;<&#xa0;0.01), indicating substantial variation influenced by both methodological and geographical factors. The funnel plot revealed marked asymmetry, suggesting potential publication bias which was confirmed by Egger's regression test (P&#xa0;<&#xa0;0.01). In conclusion, leptospirosis is widely prevalent in sheep globally, with marked geographical and methodological heterogeneity. These findings highlight the epidemiological importance of sheep in leptospirosis transmission and underscore the need for improved surveillance, standardized diagnostic approaches, and targeted control strategies within a One Health framework.

Animals↗
PubMed2004

Percutaneous exposure resulting in laboratory-acquired leptospirosis -- a case report.

A screw-capped glass tube containing a Leptospira culture accidentally broke and the laboratory worker who was handling the tube sustained a cut on his hand. The wound was flooded with the culture. The culture was that of strain MG 347 belonging to serovar Australis recovered from a patient, and it had undergone 52 passages in Ellinghausen McCullough Johnson Harris medium. The laboratory worker developed a headache 21 days after the accident and became febrile the next day. He was hospitalized for 5 days and was treated initially with doxycycline and later with ciprofloxacin. A blood sample collected on the second day of illness, after starting doxycycline therapy, yielded leptospires and the isolate, HZ 651, was identified as serovar Australis. Monoclonal antibody patterns and randomly amplified polymorphic DNA fingerprinting patterns of the isolate and strain MG 347 were identical, thus indicating that HZ 651 and MG 347 were clonal.

Adult↗
PubMed1993

Effect of streptomycin treatment on the shedding of and the serologic responses to Leptospira interrogans serovar hardjo subtype hardjobovis in experimentally infected cows.

Shedding patterns of and serologic responses to Leptospira interrogans serovar hardjo subtype hardjobovis (L. hardjobovis) have been studied in experimentally infected cows treated with streptomycin in comparison to experimentally infected cows receiving no such treatment. Fourteen cows were experimentally infected with L. hardjobovis, and blood and urine samples were collected weekly for 24 weeks. The microscopic agglutination test (MAT) and enzyme-linked immunosorbent assay (ELISA) were used to determine serologic responses. The polymerase chain reaction (PCR) was used to determine bacterial shedding in urine. Six weeks after infection six cows were treated with the antibiotic streptomycin (25 mg/kg body weight/day); three cows were treated only once, and the remaining three were treated for five consecutive days. After treatment all six cows had lower serologic responses compared to the untreated cows. The treated cows became also PCR-negative two days after the first treatment, whereas the eight untreated cows remained PCR-positive for at least 70 days. Cows that stopped shedding did not resume shedding within the observation period. Since streptomycin treatment reduces the period of shedding, transmission of leptospira via contaminated urine might be prevented by a single treatment of an infected herd.

Agglutination Tests↗
PubMed2006

A serological study on Brucella abortus, caprine arthritis-encephalitis virus and Leptospira in dairy goats in Rio de Janeiro, Brazil.

In spite of the large number of goats found in several developing tropical countries, milk production remains unsatisfactory. The occurrence of infectious diseases, such as leptospirosis, brucellosis and caprine arthritis-encephalitis (CAE) may in part be responsible for sub-optimal production. In this study, 1000 serum samples were tested for leptospirosis, 953 for brucellosis and 562 for CAE. All tested flocks presented at least one seroreactive animal for leptospirosis and for CAE. Reactivity to leptospirosis was 11.1%, and serovar hardjo was the most frequently found. Anti-B. abortus agglutinins were found in 0.5% of the samples presented and 14.1% were seroreactive to CAE. Leptospirosis was considered to represent the major infectious problem in the studied goat flocks. The occurrence of infectious diseases in the tested flocks may represent an important factor contributing to the decreased productivity of the animals. These findings may be similar to those observed in other developing countries and require further study to define the relationship between seropositivity and reduced production.

Animals↗
PubMed1998

Immobilization and health assessment of free-ranging black spider monkeys (Ateles paniscus chamek).

Eight free-ranging black spider monkeys (Ateles paniscus chamek) were immobilized with Telazol in Bolivia for the purpose of radio-collaring. During this procedure, the animals received complete medical examinations, and samples were collected for health analyses. Biochemical test results varied with the degree of condition of the animals, and a variety of physical abnormalities were found. Evidence of previous infections with Leptospira sp., encephalitis virus, and yellow fever virus was found. All findings contribute to establishing baseline health values for the species. The handling of primates for research projects provides a valuable opportunity to collect health-related data and samples that can contribute to wildlife management and conservation efforts. The capture and handling of free-ranging primates is always accompanied by risk of injury or mortality. It is ethically important to maximize the amount of information gathered during these procedures. Furthermore, sharing the undesirable impacts with the scientific community enables informed decisions to be made during future project development.

Anesthetics↗