Molecular detection of Leptospira spp. in small wild rodents from rural areas of São Paulo State, Brazil

ABSTRACT Background: Leptospirosis represents a One Health issue, affecting humans and animals. This study investigated pathogenic leptospires in small wild rodents in São Paulo, Brazil. Methods: Kidney samples from 164 rodents underwent qPCR testing, targeting pathogenic Leptospira spp. Results: Thirty-five animals (21.34%) tested positive, including five rodent species: Akodon montensis (2/21; 9.5%), Necromys lasiurus (1/4; 25%), Oligoryzomys nigripes (24/92; 26.1%), Oligoryzomys flavescens (5/26; 19.2%), and Sooretamys angouya (3/14; 21.4%). Botucatu municipality exhibited the highest prevalence, with 42.5% (20/47) of the animals testing positive. Conclusions: The presence of Leptospira spp. in wild rodents suggests they may be chronic carriers, contaminating the environment.

Leptospirosis diagnosis among patients suspected of dengue fever in Brazil

The early symptoms of leptospirosis and dengue fever are difficult to distinguish and can cause diagnostic confusion. Due to the large dengue epidemics that has occurred in Brazil in recent years, it is possible that cases of leptospirosis were unreported. Therefore, we performed a retrospective study to detect leptospirosis in patients who were tested for dengue, but whose laboratory diagnoses were negative. Methods: Sera samples from 2,017 patients from 48 cities located in the central region of São Paulo state, Brazil, were studied. All samples were subjected to the microscopic agglutination test (MAT), 305 of which were taken from patients five days or less since the onset of symptoms, and were additionally subjected to real-time polymerase chain reaction (PCR). Results: The overall prevalence of leptospirosis cases was 21 (1.04%), with 20 through MAT (18 for Icterohaemorrhagiae and two for the Cynopteri serogroup) and one through PCR (amplicon sequencing compatible with Leptospira interrogans). According to previously established criteria, eight cases of leptospirosis were classified as "confirmed" and 13 as "probable". The Brazilian notification system for health surveillance had no records for 16 patients positive for leptospirosis and, thus, they were considered unreported cases. Statistical analyses revealed that the prevalence of leptospirosis was higher in men (1.56%) than in women (0.56%), and the mean age was higher in positive patients (43.7 years) than in negative ones (32.3 years). Conclusion: The results indicated that patients suspected of dengue fever had evidence of leptospirosis or Leptospira infection, and most of these cases were unreported in the Brazilian notification system. The high burden of dengue may contribute to the misdiagnosis of leptospirosis, and health professionals should increase their awareness of leptospirosis as an important differential diagnosis of patients with suspicion of dengue.(AU)

Serological and molecular investigation of Leishmania spp. infection in cats from an area endemic for canine and human leishmaniasis in Northeast Brazil / Investigação sorológica e molecular da infecção por Leishmania spp. em gatos provenientes de uma área endêmica para leishmaniose canina e humana no nordeste brasileiro

Abstract The aim of this study was to investigate the occurrence of Leishmania spp. antibodies, and its association with feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV), in domestic cats from an area endemic for canine and human leishmaniasis in Rio Grande do Norte State, Brazil. Ninety-one cats were subjected to a complete clinical exam, and blood samples were collected. An epidemiological questionnaire was used to investigate the risk factors. IgG anti-Leishmania spp. antibodies were detected by immunofluorescence antibody test (IFAT), with a cut-off value of 1:40. Polymerase chain reaction (PCR) was performed to detect genetic material of Leishmania spp. in the blood samples. The presence of antibodies against FIV and antigens of FeLV was evaluated using an immunochromatographic test. Seropositivity for Leishmania spp., FIV, and FeLV was observed in 14/91 (15.38%), 26/91 (28.57%), and 3/91 (3.29%) cats, respectively. All samples gave negative results on PCR analysis. Based on these data, no significant statistical association was observed between seropositivity for Leishmania spp., and sex, age, presence of clinical signs, evaluated risk factors, and positivity for retroviruses. These findings demonstrated for the first time that cats from Mossoró, Rio Grande do Norte, are being exposed to this zoonosis and might be part of the epidemiological chain of transmission of visceral leishmaniasis.

Resumo O objetivo do presente estudo foi investigar a ocorrência de anticorpos contra Leishmania spp., e sua associação com o vírus da imunodeficiência felina (FIV) e o vírus da leucemia felina (FeLV), em felinos domésticos provenientes de uma área endêmica no estado do Rio Grande do Norte, para a leishmaniose visceral canina e humana. Noventa e um gatos foram submetidos a exame clínico completo e amostras de sangue foram coletadas. Um questionário epidemiológico foi feito para investigar fatores de risco. Anticorpos IgG anti-Leishmania spp. foram identificados por meio da imunofluorescência indireta (RIFI), adotando-se como ponto de corte a diluição de 1:40. A reação em cadeia da polimerase (PCR) foi executada visando detectar o material genético de Leishmania spp. a partir de amostras de sangue total. Para avaliar a presença de anticorpos contra o FIV e antígenos do FeLV foi utilizado um teste imunocromatográfico. Observou-se soropositividade em 14/91 (15,38%), 26/91 (28,57%) e 3/91 (3,29%) animais para Leishmania spp., FIV e FeLV, respectivamente. Nenhuma amostra foi positiva na PCR. Baseado nestes dados, não foi observada nenhuma associação estatística significativa entre a soropositividade para Leishmania spp. e gênero, idade, presença de sinais clínicos, fatores de risco avaliados e positividade para as retroviroses. Esses achados demonstram pela primeira vez que felinos da cidade Mossoró, Rio Grande do Norte, estão sendo expostos a esta zoonose, sugerindo que os mesmos podem estar participando da cadeia epidemiológica de transmissão da leishmaniose visceral.

Serological and molecular detection of leptospira spp in dogs

Abstract INTRODUCTION: This study aimed to detect anti-Leptospira spp antibodies and Leptospira DNA in domestic dogs. METHODS: Blood and urine from 106 dogs were evaluated by microscopic agglutination test (MAT) and polymerase chain reaction (PCR), respectively. RESULTS: Six (5.7%) and one (1%) animals were positive by MAT and PCR, respectively. CONCLUSIONS: These results show a low prevalence of infection by Leptospira spp. The absence of positive results for the Icterohaemorrhagiae serogroup indicates the small relevance of these dogs as sources of human leptospirosis.

Redescription and taxonomical considerations about Aonchotheca (Aonchotheca) pulchra n. comb. (Enoplida: Trichuridae), a nematode of Nyctinomops spp. / Redescrição e considerações taxonômicas sobre Aonchotheca (Aonchotheca) pulchra n. comb. (Enoplida: Trichuridae), um nematódeo de Nyctinomops spp.

Pterothominx pulchra (Freitas, 1934) are little known gastric nematodes of Nyctinomops laticaudatus (Chiroptera: Molossidae). Information about the occurrence and host range of these parasites in Neotropical region is still scanty, and the only two morphological descriptions available in the literature are divergent about the presence or absence of a spiny spicular sheath in males, which may lead to incorrect taxonomical positioning, since this feature represents the main difference between the genera Pterothominx and Aonchotheca. Based on the absence of this morphological feature in specimens of this nematode obtained from N. laticaudatus and Nyctinomops macrotis bats captured in two municipalities in the state of São Paulo, Brazil, the present study reclassifies the aforementioned species in the genus Aonchotheca and allocates it to the subgenus Aonchotheca. Additional morphometric data and new host and locality records are also provided.

Pterothominx pulchra (Freitas, 1934) são nematódeos gástricos pouco conhecidos de Nyctinomops laticaudatus (Chiroptera: Molossidae). Informações referentes à ocorrência e variedade de hospedeiros desses parasitos ainda são escassas na região Neotropical. As únicas duas descrições morfológicas disponíveis na literatura são divergentes entre si quanto à presença de bainha espicular espinhosa nos machos, o que resultou no posicionamento taxonômico equivocado desta espécie, uma vez que, é a principal característica para diagnóstico dos gêneros Pterothominx e Aonchotheca. Baseado na ausência dessa característica morfológica em espécimes desse nematódeo, obtidos em morcegos N. laticaudatus e Nyctinomops macrotis capturados em dois municípios do Estado de São Paulo, Brasil, o presente estudo classifica a referida espécie no gênero Aonchotheca e a aloca no subgênero Aonchotheca, além de fornecer dados morfométricos adicionais e novos registros de hospedeiro e localidades.

Prevalence of antibodies against Toxoplasma gondii and Neospora caninum in dogs

Toxoplasmosis and neosporosis are parasitic diseases of global importance. The present study had the objective to determine the influence of age, sex and breed in the prevalence of antibodies against both diseases in dogs from Brotas city, São Paulo State, Brazil. Blood samples of 342 dogs were collected, and the age, sex and breed of each animal were recorded. The serological diagnosis for toxoplasmosis and neosporosis were performed using the immunofluorescent antibody test (IFAT). The Fischer's test was used to calculate the association probability of the variables, with a = 5%. For toxoplasmosis the prevalence of antibodies was 26.9% (CI 95% 22.4-31.8%), and for neosporosis 4.97% (CI 95% 3.1-7.8%). The statistical analysis revealed a higher risk of infection for T. gondii in dogs with more than five years.

Canine distemper virus infection in a lesser grison (Galictis cuja): first report and virus phylogeny / Infecção pelo vírus da cinomose canina em um furão (Galictis cuja): primeiro relato e filogenia viral

Infectious diseases in wild animals have been increasing as a result of their habitat alterations and closer contact with domestic animals. Canine distemper virus (CDV) has been reported in several species of wild carnivores, presenting a threat to wildlife conservation. We described the first case of canine distemper virus infection in lesser grison (Galictis cuja). A free-ranging individual, with no visible clinical sigs, presented sudden death after one day in captivity. Molecular diagnosis for CDV infection was performed using whole blood collected by postmortem intracardiac puncture, which resulted positive. The virus phylogeny indicated that domestic dogs were the probable source of infection.

Doenças infecciosas em animais selvagens têm aumentado devido às alterações em seu habitat e ao maior contato com animais domésticos. A cinomose já foi descrita em diversas espécies de carnívoros selvagens, representando uma ameaça à conservação da vida selvagem. Nesse estudo é descrito o primeiro caso de infecção pelo vírus da cinomose em um furão (Galictis cuja). Um indivíduo de vida livre, sem sinais clínicos aparentes, apresentou morte súbita após um dia em cativeiro. Foi realizado o diagnóstico molecular para detecção do vírus da cinomose canina, sendo o resultado positivo. A filogenia do vírus indicou que cães domésticos foram a provável fonte de infecção.

Serological investigation and PCR in detection of pathogenic leptospires in snakes / Investigação sorológica e PCR na detecção de leptospiras patogênicas em serpentes

Detection of Leptospira by PCR had not yet been described in snakes. This study investigated, by microscopic agglutination test (MAT) and PCR, the presence of antibodies to Leptospira spp. and Leptospira spp., respectively, in venomous and non-venomous wildlife and captivity snakes. All snakes were divided into three groups to be compared: Group 1 (wildlife snakes - WS); Group 2 (snakes in intensive captivity - IC), and Group 3 (collective semi-extensive captivity -CC). Of the 147 snakes studied, 52 (35.4 percent) were positive for leptospirosis by MAT, 8 (15.4 percent) belonging to Group 1 (WS), 34 (65.4 percent) to Group 2 (IC) and 10 (19.2 percent) to Group 3 (CC). Jararaca (Bothrops jararaca) presented the highest average titer (66.7 percent, N=22/33) among the three group studied, and Hardjo prajtino was the most prevalent serovar (88.5 percent, N=46/52), with titers varying from 100 to 3200. Leptospira interrogans was revealed by PCR in kidney and liver of caiçaca (Bothrops moojeni) and jararaca-pintada (Bothrops pauloensis), showing 100 percent and 93 percent identity respectively. Future studies should be carried out for better understanding of the role of snakes as a reservoir of Leptospira in nature.

A detecção de Leptospira pela técnica de PCR não havia sido descrita em serpentes. Este estudo investigou pelo teste de aglutinação microscópica (MAT) e PCR, a presença de anticorpos anti-Leptospira spp. e Leptospira spp., respectivamente, em serpentes peçonhentas e não peçonhentas de vida livre e de cativeiro. As serpentes foram divididas em três grupos para comparação: Grupo 1 (serpentes recém-chegadas da natureza - WS); Grupo 2 (serpentes em regime de cativeiro intensivo -IC) e Grupo 3 (serpentes em regime de cativeiro coletivo semi-extensivo - CC). Do total de 147 serpentes estudadas, 52 (35,4 por cento) foram positivas para leptospirose pelo MAT, as quais 8 (15,4 por cento) pertenciam ao Grupo 1 (WS), 34 (65,4 por cento) ao Grupo 2 (IC) e 10 (19,2 por cento) ao Grupo 3 (CC). Das espécies estudadas, a jararaca (Bothrops jararaca) apresentou maior soropositividade (66,7 por cento, N=22/33). O sorovar mais prevalente foi o Hardjo prajtino (88,5 por cento, N=46/52) e os títulos variaram de 100 a 3200. Leptospira interrogans foi revelada por PCR nos rins e no fígado de caiçaca (Bothrops moojeni) e de jararaca-pintada (Bothrops pauloensis), mostrando 100 por cento e 93 por cento de identidade, respectivamente. Futuros estudos devem ser realizados para melhor compreensão do papel das serpentes como reservatório de leptospiras na natureza.