Lyophilization for bacteria preservation: a promising approach for Yersinia pestis strains from an unique collection in Brazil (Fiocruz-CYP).

Yersinia pestis, the causative agent of plague, is a highly virulent bacterium that poses a significant threat to human health. Preserving this bacterium in a viable state is crucial for research and diagnostic purposes. This paper presents and evaluates a simple lyophilization protocol for the long-term storage of Y.

Evaluation of a multi-species Protein A-ELISA assay for plague serologic diagnosis in humans and other mammal hosts.

Background: The Hemagglutination assay (HA) is widely used in plague diagnosis, however, it has a subjective interpretation and demands high amounts of antigen and other immunobiological supplies. On the other hand, the conventional Anti-IgG ELISA is limited by the need of specific conjugates for multiple plague hosts, which leaves a gap for new diagnostic methods able to cover both the diagnosis of human cases and the epidemiological surveillance of multiple sentinel species.

Methods: We developed an ELISA Protein A-peroxidase method to detect anti-F1 antibodies across several species, including humans.

Performance assessment of a new indirect rapid diagnostic test for plague detection in humans and other mammalian hosts.

Plague is a flea-borne zoonosis that affects a wide range of mammals and still causes outbreaks in human populations yearly across several countries. While crucial for proper treatment, early diagnosis is still a major challenge in low- and middle-income countries due to poor access to laboratory infrastructure in rural areas. To tackle this issue, we developed and evaluated a new Fraction 1 capsular antigen (F1)-based rapid diagnostic test (RDT) as an alternative method for plague serological diagnosis and surveillance in humans and other mammals.

Spatial and Temporal Distribution of Rodents during the Epizootic and Enzootic Periods of Plague, with a Focus on Exu, Northeastern Brazil.

The plague caused by the bacterium is primarily a flea-transmitted zoonosis of rodents that can also be conveyed to humans and other mammals. In this work, we analyzed the spatial and temporal distribution of rodent populations during epizootic and enzootic periods of the plague in the municipality of Exu, northeastern Brazil. The geospatial analyses showed that all the rodent species appeared through the whole territory of the municipality, with different occurrence hotspots for the different species.

Spatiotemporal analysis of bubonic plague in Pernambuco, northeast of Brazil: Case study in the municipality of Exu.

Along with other countries in America, plague reached Brazil through the sea routes during the third pandemic. A brief ports phase was followed by an urban phase that took place in smaller inland cities and finally, it attained the rural area and established several foci where the ecological conditions were suitable for its continued existence. However, the geographic dispersion of plague in Brazil is still poorly studied.

Rodent hosts and flea vectors in Brazilian plague foci: a review.

Plague, caused by the Yersinia pestis bacterium, has several foci scattered throughout a large area from the Brazilian territory that ranges from the Northeastern State of Ceará to the Southeastern State of Minas Gerais and another separated area at the State of Rio de Janeiro. This review gathers data from plague control and surveillance programs on the occurrence and geographic distribution of rodent hosts and flea vectors in the Brazilian plague areas during the period of from 1952 to 2019. Furthermore, we discuss how the interaction between Y.

High-resolution genome-wide analysis is essential for the identification of ambiguous Aeromonas strains.

Aeromonads are mainly opportunistic pathogens; however, many species are emerging as important human pathogens. Therefore, monitoring these bacteria and their accurate characterization of its species is highly important. Aeromonas Aer593 strain was recovered from a diarrhoea outbreak and did not group with any previously described Aeromonas species by housekeeping gene sequencing.

Microscopic detection of Mycobacterium tuberculosis in direct or processed sputum smears.

Introduction: Microscopic identification of active pulmonary tuberculosis (PTB) from direct smears of sputum (DS) is widely used for detection, but has limited sensitivity. Here, we assessed the yield of acid-fast bacilli (AFB) detection in processed sputum smears (PSS).

Methods: Sputum samples were simultaneously analyzed by direct sputum smearing and after chemical treatment and spontaneous sedimentation.

Seroprevalence and spatial distribution dynamics of Yersinia pestis antibodies in dogs and cats from plague foci in the State of Ceará, Northeastern Brazil.

Introduction: In Brazil, the plague is established in several foci located mainly in the northeastern part of the country, where it alternates between active and quiescent periods. These foci in the State of Ceará have high epidemiological importance. In addition to other plague detection activities, plague areas can be monitored through serological surveys of dogs and cats (domestic carnivores), which, following feeding on plague-infected rodents, can develop mild to severe forms of the disease and produce long-lasting antibodies.

Genetic diversity and virulence potential of clinical and environmental Aeromonas spp. isolates from a diarrhea outbreak.

Background: Aeromonas spp. are gram-negative bacteria that can cause a variety of infections in both humans and animals and play a controversial role in diarrhea outbreaks. Our aim was to identify clinical and environmental Aeromonas isolates associated with a cholera outbreak in a northeast county of Brazil at the species level.

Ehrlichia canis and Rickettsia spp. in dogs from urban areas in Paraiba state, northeastern Brazil.

The aims of our study was to identify Ehrlichia canis and antibodies against Rickettsia spp. belonging to the spotted fever group (SFG) in dogs sampled from Paraiba state, northeastern Brazil. Blood and serum samples collected by convenience from dogs in urban areas of five municipalities were analyzed by real-time PCR for the detection of E.

Rodents and other small mammal reservoirs in plague foci in northeastern Brazil.

Introduction: Plague is an acute, infectious zoonotic disease, primarily of wild rodents and their fleas, that affects humans and other mammals. In Brazil, several plague foci are located in the northeast region. Plague surveillance based on monitoring of rodents was discontinued in 2007, and the current information on rodent populations is unsatisfactory.

Zoonoses As Ecological Entities: A Case Review of Plague.

As a zoonosis, Plague is also an ecological entity, a complex system of ecological interactions between the pathogen, the hosts, and the spatiotemporal variations of its ecosystems. Five reservoir system models have been proposed: (i) assemblages of small mammals with different levels of susceptibility and roles in the maintenance and amplification of the cycle; (ii) species-specific chronic infection models; (ii) flea vectors as the true reservoirs; (iii) Telluric Plague, and (iv) a metapopulation arrangement for species with a discrete spatial organization, following a source-sink dynamic of extinction and recolonization with naïve potential hosts. The diversity of the community that harbors the reservoir system affects the transmission cycle by predation, competition, and dilution effect.

Seroprevalence of hantavirus and Yersinia pestis antibodies in professionals from the Plague control program.

Introduction: Professionals who handle rodents in the field and in the laboratory are at risk of infection by the microorganis mharbored by these animals.

Methods: Serum samples from professionals involved in rodent and Yersinia pestis handling in field or laboratory work were analyzed to determine hantavirus and plague seroprevalence and to establish a relationship between these activities and reports of illnesses.

Results: Two individuals had antibodies against hantavirus, and two harbored antibodie against the plague; none of the individuals had experienced an illness related to their duties.

The aquatic environment as a reservoir of Vibrio cholerae O1 in hydrographic basins of the state of Pernambuco, Brazil.

After the worldwide cholera epidemic in 1993, permanent environmental monitoring of hydrographic basins was established in Pernambuco, Brazil, where cholera is endemic. After a quiescent period, 4 rfbN (serogroup O1) positive water samples that were culture negative were detected by multiplex single-tube nested PCR (MSTNPCR); 2 of these were also ctxA (cholera toxin) positive. From May to June 2012, 30 V.

Occupationally acquired american cutaneous leishmaniasis.

WE REPORT TWO OCCUPATIONALLY ACQUIRED CASES OF AMERICAN CUTANEOUS LEISHMANIASIS (ACL): one accidental laboratory autoinoculation by contaminated needlestick while handling an ACL lesion sample, and one acquired during field studies on bird biology. Polymerase chain reaction (PCR) assays of patient lesions were positive for Leishmania, subgenus Viannia. One isolate was obtained by culture (from patient 2 biopsy samples) and characterized as Leishmania (Viannia) naiffi through an indirect immunofluorescence assay (IFA) with species-specific monoclonal antibodies (mAbs) and by multilocus enzyme electrophoresis (MLEE).

An assessment of whole blood and fractions by nested PCR as a DNA source for diagnosing canine ehrlichiosis and anaplasmosis.

Ehrlichiosis and anaplasmosis are tick-borne diseases. Ehrlichia canis and Anaplasma platys infect mainly white cells and platelets, respectively. The main DNA source for PCR is peripheral blood, but the potential of blood cell fractions has not been extensively investigated.

Cutaneous leishmaniasis in northeastern Brazil: a critical appraisal of studies conducted in State of Pernambuco.

American cutaneous leishmaniasis (ACL) is a complex disease with clinical and epidemiological features that may vary from region to region. In fact, at least seven different Leishmania species, including Leishmania (Viannia) braziliensis, Leishmania (Viannia) guyanensis, Leishmania (Viannia) lainsoni, Leishmania (Viannia) naiffi, Leishmania (Viannia) shawi, Leishmania (Viannia) lindenbergi, and Leishmania (Leishmania) amazonensis, have been implicated in the etiology of ACL in Brazil, and numerous phlebotomine sandfly species of the genus Lutzomyia have been regarded as putative or proven vectors. Because ACL is a focal disease, understanding the disease dynamics at the local level is essential for the implementation of more effective control measures.

[Biosafety, environmental protection and health: completing the puzzle].

This work reflects on the development of the field of Biosafety. The scope of this field is presented, as well as its complex themes and its interdisciplinary perspective. The scope of this field is to propose actions capable of preventing and controlling the risk of worsening human and environmental health.

[Prevalence of antibodies against Yersinia pestis in domestic carnivores, in plague foci in the State of Ceará].

The prevalence of antibodies against Yersinia pestis in domestic carnivores (dogs and cats), in plague areas in the State of Ceará, was analyzed to establish the importance of monitoring these animals within the routine practice of the plague control program. Over the decade 1997-2006, 146,732 serum samples were examined (95,883 from dogs and 50,849 from cats), of which 2,629 (2,234 from dogs and 395 from cats) proved to be positive. The prevalence among dogs (85%) was higher than among cats (15%) throughout the decade and in all places, except in Ibiapina in 1998.