Cases distribution of leptospirosis in City of Manaus, State of Amazonas, Brazil, 2000-2010

INTRODUCTION: Leptospirosis is an infectious disease caused by microorganisms of the genus Leptospira that affects several species of animals, including the human beings. The study described the confirmed cases of leptospirosis in Manaus, from 2000 to 2010. METHODS: A descriptive study based on secondary data analysis of Secretaria Municipal de Saúde (SEMSA), Sistema de Informação de Agravos de Notificação SINAN and Sistema de Informação sobre Mortalidade (SIM) analyzing the variables: age group, gender, clinical aspects and geographic area and lethality. RESULTS: Were reported 665 cases of leptospirosis, 339 were confirmed and 35 (10.3%) died. The largest number of cases occurred in May (16.8%), March (13.3%) and April (11.4%), a period of intense rainfall. The city areas with the greatest occurrence of the disease were South (26.6%), West (23.5%) and East (19.7%), areas of the greatest precariousness socio-environment. The largest number of cases, including deaths, occurred in the age group from 14 to 44.9 years (74%), being that 291 (85.8%) were male and 48 (14.1%) females. The most frequent symptoms were fever, myalgia, headache and jaundice. In relation to the social conditions were identified low education, poor housing, absence of sanitation and low income. CONCLUSIONS: In Manaus, despite the implementation of the Social and Environmental Program of Igarapés of Manaus (PROSAMIM), there are still areas that need a proper urbanization and improvements in socio-environmental conditions, reducing the level of exposure of the human beings that living in these locations.

Haemoglobin and red cell counts in leptospirosis patients infected with different serovars

IntroductionThe aim of the study was to compare haemoglobin and red cell counts between patients known to be infected with a range of leptospiral serovars.MethodsThe study retrospectively compared the haemoglobin and red cell count results from the first blood samples taken from 207 patients at presentation to a Queensland Health hospital.ResultsSignificant differences were observed in haemoglobin and red cell counts in those infected with Leptospira interrogans serovars Szwajizak and Canicola when compared with most of the other serovars.ConclusionsThese findings suggest that haemoglobin and red cell counts may be useful in differentiating leptospiral serovars in leptospirosis patients.

Leptospirosis in animals and human contacts in Egypt: broad range surveillance

INTRODUCTION: Leptospirosis is a re-emerging zoonotic disease of humans and animals worldwide. The disease is caused by pathogenic species of the genus Leptospira. These organisms are maintained in nature via chronic renal infection of carrier animals, which excrete the organisms in their urine. Humans become infected through direct or indirect exposure to infected animals and their urine or through contact with contaminated water and soil. This study was conducted to investigate Leptospira infections as a re-emerging zoonosis that has been neglected in Egypt. METHODS: Samples from 1,250 animals (270 rats, 168 dogs, 625 cows, 26 buffaloes, 99 sheep, 14 horses, 26 donkeys and 22 camels), 175 human contacts and 45 water sources were collected from different governorates in Egypt. The samples were collected from different body sites and prepared for culture, PCR and the microscopic agglutination test (MAT). RESULTS: The isolation rates of Leptospira serovars were 6.9%, 11.3% and 1.1% for rats, dogs and cows, respectively, whereas the PCR results revealed respective detection rates of 24%, 11.3% and 1.1% for rats, dogs and cows. Neither the other examined animal species nor humans yielded positive results via these two techniques. Only six Leptospira serovars (Icterohaemorrhagiae, Pomona, Canicola, Grippotyphosa, Celledoni and Pyrogenes) could be isolated from rats, dogs and cows. Moreover, the seroprevalence of leptospiral antibodies among the examined humans determined using MAT was 49.7%. CONCLUSIONS: The obtained results revealed that rats, dogs and cows were the most important animal reservoirs for leptospirosis in Egypt, and the high seroprevalence among human contacts highlights the public health implications of this neglected zoonosis.

Leptospirose e Fasciolose: Interacções imunológicas no polimorfismo do quadro clínico dos doentes de São Miguel (Açores)

O arquipélago dos Açores apresenta nove ilhas vulcânicas, sendo São Miguel a maior e mais populosa. Nesta região insular portuguesa, a Leptospirose é uma zoonose endémica, que afeta acidentalmente o Homem por contacto direto ou indireto com leptospiras patogénicas. Clinicamente, esta patologia apresenta diversos sintomas que podem ser semelhantes a uma gripe ou evoluir até um quadro fulminante, daí a necessidade de um diagnóstico preciso com confirmação laboratorial. A Fasciolose é outra importante doença zoonótica nos Açores que tem sido descrita como endémica neste arquipélago, causada pelo parasita Fasciola hepatica. A infeção humana pode ocorrer devido ao consumo de vegetais e/ou águas contaminados. O diagnóstico não é fácil, pois a infeção pelo parasita pode apresentar uma larga variedade de quadros clínicos. O objetivo deste estudo é contribuir para a clarificação de uma possível interação imunológica, ao nível da resposta humoral observada em indivíduos com diagnóstico clínico de Leptospirose e/ou Fasciolose, em pacientes da ilha de São Miguel que apresentam um quadro clínico e epidemiológico comum a ambas as patologias, contribuindo para um melhor diagnóstico diferencial. A amostra utilizada no estudo é composta por 280 soros de indivíduos residentes na ilha de São Miguel, que foram analisados entre 2005 e 2010 pela TAM (Técnica de Aglutinação Microscópica), para deteção de aglutininas anti-Leptospira interrogans s.l.. Nas amostras de soro com resultado positivo e inconclusivo pela TAM foi aplicada a técnica de rastreio micro-ELISA para o estudo da Fasciolose. Aplicou-se ainda a técnica de Imunoeletrodifusão (IED), como técnica confirmatória, nos soros com resultado positivo e em alguns inconclusivos (n=118) para a técnica micro-ELISA. Os resultados da TAM, previamente conhecidos, para o total de indivíduos estudados foram os seguintes: 124 (44,3%) negativos, 73 (26,1%) inconclusivos e 83 (29,6%) positivos. Estes soros foram submetidos ao teste micro-ELISA, tendo-se obtido 31,1% (n=87) resultados positivos, 31,4% (n=88) resultados inconclusivos e 37,5% (n=105) com resultado negativo para Fasciolose. Foram analisados os inquéritos clínico-epidemiológicos estabelecido para o estudo da Leptospirose humana em São Miguel para as amostras anteriormente referidas, verificando-se que os homens lavradores em idade ativa são o grupo com mais casos positivos para ambas as patologias. Além disso, os sinais e sintomas mais comuns nos doentes com resultado positivo para as duas doenças são semelhantes aos de uma gripe, e analiticamente foi notório que as transaminases, a FA/γGT (apenas nos doentes com Leptospirose) e a leucocitose tinham níveis elevados. Os resultados revelaram uma provável coinfeção em 36 doentes. A técnica de IED foi positiva em 28 amostras de soro, sendo que cinco tiveram resultado positivo para as três técnicas utilizadas. Estes resultados são promissores, demonstrando uma possível relação entre Leptospirose e Fasciolose, sendo que os respetivos agentes etiológicos partilham nichos ecológicos, o que justifica igualmente algumas semelhanças nos aspetos sociodemográficos e clínico-epidemiológicos na população afetada.

Seroprevalence for brucellosis and leptospirosis in dogs from Belém and Castanhal, State of Pará, Brazil

Brucellosis and leptospirosis are widely spread bacterial infections and dogs are the most important source of infection and reservoir for diseases. Dogs can disseminate the agents in the environment and transmit them to humans and/or other animals. The objective of this study was assess the occurrence of reactive to antibodies anti-Leptospira spp., Brucella canis and B. abortus in Belém and Castanhal, State of Pará, Amazon, Brazil. A total of 156 samples were randomly collected in the city of Belém and 158 samples in Castanhal. The anti-B. canis antibodies research was performed by Agar Gel Immunodiffusion (AGID) with and without 2-mercaptoethanol serum treatment (AGID-2ME). To assess the anti-B. abortus antibodies, the technique of Fast Seroagglutination with buffered acidified plate antigen (BAPAT) was used. For anti-Leptospira spp. antibodies research, the Microscopic Agglutination Technique (MAT) was used. No animal reacted to Brucella abortus and one animal was reactive to B. canis at the AGID, but it was negative to the AGID-2ME test. Seventeen percent of dogs (47/274) presented anti-Leptospira spp. antibodies, with prevalence of serovar Canicola. The dogs from Belém and Castanhal are not source of infection for B. abortus and B. canis, however, they are reservoirs for different serovars of Leptospira spp.

Estudio de prospección serológica de brucelosis y leptospirosis canina

Las enfermedades infecciosas bacterianas del perro de mayor importancia en salud pública son la Brucelosis y la Leptospirosis canina. Ambas enfermedades se encuentran mundialmente difundidas. En nuestro país no se conocen datos concretos de prevalencia. Si bien las pérdidas que generan en criaderos comerciales son cuantiosas, no se comparan con el riesgo zoonótico que estas patologías representan para la comunidad. El agente etiológico de la Brucelosis en el perro, es principalmente B. canis , aunque también se describen infecciones con cepas de B. abortus, melitensis y suis.El diagnóstico de esta enfermedad es diferente según el tipo de cepa actuante. (...) El agente etiológico de la Leptospirosis en el perro es principalmente Leptospira canicola, pero también se afecta con otros serovares del género L. interrogans. Este animal juega un rol muy importante como diseminador del microorganismo en el medio ambiente y de allí la posibilidad de contagio al hombre, ya que la enfermedad se transmite por contacto directo con material contaminado como agua, tierra, vegetales contaminados con orina de animales infectados. (...) Objetivo general: Se plantea como objetivo del presente proyecto, determinar la tasa de infección a B. spp, y Leptospira interrogans en los perros ingresados al hospital de Clínica Animal de la Facultad de Agronomía y Veterinaria de la Universidad Nacional de Río Cuarto. Objetivos específicos: 1. Elaborar el antígeno para realizar la técnica de Inmunodifusión utilizada en el diagnóstico de Brucella canis. 2. Realizar la técnica de ID y compararla con los resultados obtenidos mediante técnicas de aglutinación capaces de detectar la infección por B. abortus. (BPA, Rosa de Bengala, 2ME, Lenta en tubo Wright). 3. Hemocultivo de animales serológicamente positivos a Brucella sp. 4. Determinar mediante la técnica de microaglutinación, las tasa de infección frente a distintos serovares de Letospira interrogans.

Search for Borrelia sp. in ticks collected from potential reservoirs in an urban forest reserve in the State of Mato Grosso do Sul, Brazil: a short report

A total of 128 ticks of the genus Amblyomma were recovered from 5 marsupials (Didelphis albiventris) - with 4 recaptures - and 17 rodents (16 Bolomys lasiurus and 1 Rattus norvegicus) captured in an urban forest reserve in Campo Grande, State of Mato Grosso do Sul, Brazil. Of the ticks collected, 95 (78.9%) were in larval form and 22 (21.1%) were nymphs; the only adult (0.8%) was identified as A. cajennense. Viewed under dark-field microscopy in the fourth month after seeding, 9 cultures prepared from spleens and livers of the rodents, blood of the marsupials, and macerates of Amblyomma sp. nymphs revealed spiral-shaped, spirochete-like structures resembling those of Borrelia sp. Some of them showed little motility, while others were non-motile. No such structures could be found either in positive Giemsa-stained culture smears or under electron microscopy. No PCR amplification of DNA from those cultures could be obtained by employing Leptospira sp., B. burgdorferi, and Borrelia sp. primers. These aspects suggest that the spirochete-like structures found in this study do not fit into the genera Borrelia or Leptospira, requiring instead to be isolated for proper identification.

The humoral immune response to recombinant nucleocapsid antigen of canine distemper virus in dogs vaccinated with attenuated distemper virus or DNA encoding the nucleocapsid of wild-type virus.

This study compared the humoral immune response against the nucleocapsid-(N) protein of canine distemper virus (CDV) of dogs vaccinated with a multivalent vaccine against parvo-, adeno-, and parainfluenza virus and leptospira combined with either the attenuated CDV Onderstepoort strain (n = 15) or an expression plasmid containing the N-gene of CDV (n = 30). The vaccinations were applied intramuscularly three times at 2-week intervals beginning at the age of 6 weeks. None of the pre-immune sera recognized the recombinant N-protein, confirming the lack of maternal antibodies at this age. Immunization with DNA vaccine for CDV resulted in positive serum N-specific IgG response. However, their IgG (and IgA) titres were lower than those of CDV-vaccinated dogs. Likewise, DNA-vaccinated dogs did not show an IgM peak. There was no increase in N-specific serum IgE titres in either group. Serum titres to the other multivalent vaccine components were similar in both groups.

Using a top predator as a sentinel for environmental contamination with pathogenic bacteria: the Iberian wolf and leptospires

The Iberian wolf (Canis lupus) is the top predator in the Iberian environments in which it lives, feeding on a wide range of species, thus encountering a wide range of disease agents. Therefore, the wolf can serve as sentinel of environmental contamination with pathogens. We investigated the exposure of free-living wolves to 14 serovars of Leptospira interrogans sensu lato. Kidney samples from 49 wolves collected from 2010-2013 in northwestern Spain were analysed by culture, direct immunofluorescence and polymerase chain reaction. Tissue fluids were analysed for antibodies by a microscopic agglutination test. Ten wolves (observed prevalence: 20%, 95% confidence interval = 11-33%) showed evidence of contact with leptospires, eight through direct detection and nine through serology (7 wolves were positive according to both techniques). Titres below the cut-off level were also detected in seven cases. Serovars confirmed were Canicola (n = 4), Icterohaemorrhagiae (n = 3) and Sejroë, Ballum and Grippotyphosa (n = 1 each), indicating that wolves were infected with serovars for which dogs, rodents and ungulates, are the natural hosts and supporting the utility of the wolf and other large predators as environmental sentinels for pathogens.

The use of halloysite clay and carboxyl-functionalised multi-walled carbon nanotubes for recombinant LipL32 antigen delivery enhanced the IgG response

We studied the feasibility of using halloysite clay nanotubes (HNTs) and carboxyl-functionalised multi-walled carbon nanotubes (COOH-MWCNTs) as antigen carriers to improve immune responses against a recombinant LipL32 protein (rLipL32). Immunisation using the HNTs or COOH-MWCNTs significantly increased the rLipL32-specific IgG antibody titres (p < 0.05) of Golden Syrian hamsters. None of the vaccines tested conferred protection against a challenge using a virulent Leptospira interrogans strain. These results demonstrated that nanotubes can be used as antigen carriers for delivery in hosts and the induction of a humoral immune response against purified leptospiral antigens used in subunit vaccine preparations.

Molecular characterisation and disease severity of leptospirosis in Sri Lanka

Leptospirosis is a re-emerging zoonotic disease all over the world, important in tropical and subtropical areas. A majority of leptospirosis infected patients present as subclinical or mild disease while 5-10% may develop severe infection requiring hospitalisation and critical care. It is possible that several factors, such as the infecting serovar, level of leptospiraemia, host genetic factors and host immune response, may be important in predisposition towards severe disease. Different Leptospirastrains circulate in different geographical regions contributing to variable disease severity. Therefore, it is important to investigate the circulating strains at geographical locations during each outbreak for epidemiological studies and to support the clinical management of the patients. In this study immunochromatography, microscopic agglutination test and polymerase chain reaction were used to diagnose leptospirosis. Further restriction fragment length polymorphism and DNA sequencing methods were used to identify the circulating strains in two selected geographical regions of Sri Lanka.Leptospira interrogans, Leptospira borgpeterseniiandLeptospira kirschneristrains were identified to be circulating in western and southern provinces. L. interroganswas the predominant species circulating in western and southern provinces in 2013 and its presence was mainly associated with renal failure.

DNA prime-protein boost based vaccination with a conserved region of leptospiral immunoglobulin-like A and B proteins enhances protection against leptospirosis

Leptospirosis is a zoonotic disease caused by pathogenic spirochetes of theLeptospira genus. Vaccination with bacterins has severe limitations. Here, we evaluated the N-terminal region of the leptospiral immunoglobulin-like B protein (LigBrep) as a vaccine candidate against leptospirosis using immunisation strategies based on DNA prime-protein boost, DNA vaccine, and subunit vaccine. Upon challenge with a virulent strain ofLeptospira interrogans, the prime-boost and DNA vaccine approaches induced significant protection in hamsters, as well as a specific IgG antibody response and sterilising immunity. Although vaccination with recombinant fragment of LigBrep also produced a strong antibody response, it was not immunoprotective. These results highlight the potential of LigBrep as a candidate antigen for an effective vaccine against leptospirosis and emphasise the use of the DNA prime-protein boost as an important strategy for vaccine development.

Maladie de Weil: à propos d'un cas de leptospirose acquise en Suisse [Weil's disease: a case report of acquired leptospirosis in Switzerland].

Leptospirosis is a rare disease in Switzerland. However its incidence is probably underestimated, due to its broad spectrum of presentations, including subclinical benign forms and the ictero-hemorragic form of the Weil's syndrome, whose mortality is high. We describe here a case of Weil's syndrome acquired in Switzerland with a favourable outcome under antibiotherapy. Even in the absence of any travel, the association of an acute renal insufficiency and jaundice with only moderate hepatic cytolysis should lead to the suspicion of leptospirosis. Clinical and epidemiological aspects of the disease are discussed in the article.

Bacterial variations on the methionine salvage pathway.

BACKGROUND: The thiomethyl group of S-adenosylmethionine is often recycled as methionine from methylthioadenosine. The corresponding pathway has been unravelled in Bacillus subtilis. However methylthioadenosine is subjected to alternative degradative pathways depending on the organism. RESULTS: This work uses genome in silico analysis to propose methionine salvage pathways for Klebsiella pneumoniae, Leptospira interrogans, Thermoanaerobacter tengcongensis and Xylella fastidiosa. Experiments performed with mutants of B. subtilis and Pseudomonas aeruginosa substantiate the hypotheses proposed. The enzymes that catalyze the reactions are recruited from a variety of origins. The first, ubiquitous, enzyme of the pathway, MtnA (methylthioribose-1-phosphate isomerase), belongs to a family of proteins related to eukaryotic intiation factor 2B alpha. mtnB codes for a methylthioribulose-1-phosphate dehydratase. Two reactions follow, that of an enolase and that of a phosphatase. While in B. subtilis this is performed by two distinct polypeptides, in the other organisms analyzed here an enolase-phosphatase yields 1,2-dihydroxy-3-keto-5-methylthiopentene. In the presence of dioxygen an aci-reductone dioxygenase yields the immediate precursor of methionine, ketomethylthiobutyrate. Under some conditions this enzyme produces carbon monoxide in B. subtilis, suggesting a route for a new gaseous mediator in bacteria. Ketomethylthiobutyrate is finally transaminated by an aminotransferase that exists usually as a broad specificity enzyme (often able to transaminate aromatic aminoacid keto-acid precursors or histidinol-phosphate). CONCLUSION: A functional methionine salvage pathway was experimentally demonstrated, for the first time, in P. aeruginosa. Apparently, methionine salvage pathways are frequent in Bacteria (and in Eukarya), with recruitment of different polypeptides to perform the needed reactions (an ancestor of a translation initiation factor and RuBisCO, as an enolase, in some Firmicutes). Many are highly dependent on the presence of oxygen, suggesting that the ecological niche may play an important role for the existence and/or metabolic steps of the pathway, even in phylogenetically related bacteria. Further work is needed to uncover the corresponding steps when dioxygen is scarce or absent (this is important to explore the presence of the pathway in Archaea). The thermophile T. tengcongensis, that thrives in the absence of oxygen, appears to possess the pathway. It will be an interesting link to uncover the missing reactions in anaerobic environments.

Aborto por Aspergillus fumigatus e A. niger em bovinos no sul do Brasil

As infecções micóticas apresentam distribuição mundial e podem causar placentite e aborto em diversas espécies de animais. Entre setembro 2001 e novembro 2002, foram processados no Setor de Patologia Veterinária, Universidade Federal do Rio Grande do Sul, 147 fetos bovinos abortados com o objetivo de avaliar as principais causas de aborto infeccioso bovino no sul do Brasil. Destes, 34 estavam acompanhados da placenta. Aborto micótico foi diagnosticado em cinco casos (3,4%) mediante cultivo puro de quatro amostras de Aspergillus fumigatus e uma de A. niger associado a lesões histológicas características de fungo. Os exames virológico, bacteriológico e imunofluorescência direta para Leptospira sp foram negativos nestes casos. A idade dos fetos variava entre 5 e 8 meses de idade. Lesões macroscópicas foram observadas em quatro casos e eram caracterizadas por áreas circulares multifocais branco-acinzentadas na pele, principalmente na região da cabeça e dorso, em dois fetos, lesões nodulares no fígado em um caso e espessamento dos cotilédones em duas placentas enviadas juntamente com os fetos. Lesões histológicas foram observadas principalmente no fígado, pulmão e placenta, caracterizadas por hepatite necrótica multifocal, broncopneumonia supurativa e placentite necrótica. Através da coloração de Grocott hifas septadas foram observadas em duas placentas e nas bordas das lesões necróticas no fígado de um feto. Em dois casos hifas foram observadas somente na placenta e não no feto, salientando-se a importância deste tecido para o diagnóstico de aborto micótico bovino.