Andrea Pires dos Santos

Dr. Andrea Pires dos Santos

orcid

Research Focus & Metrics

Academic Career Length

19Years (2008-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
1 December 2008 in Emerging Infectious Diseases
Verified
Journal Article
Open access
ASAndrea Pires dos Santos
Andrea Pires dos Santos
RSRodrigo Pires dos Santos
Rodrigo Pires dos Santos
Alexander Welker BiondoAlexander Welker Biondo
Alexander Welker Biondo
JDJOSE MIGUEL SILVA DORA
JOSE MIGUEL SILVA DORA
LGLuciano Z. Goldani
Luciano Z. Goldani
JMJoanne B. Messick
Joanne B. Messick
Hemotrophic mycoplasmas infect a variety of mammals. Although infection in humans is rarely reported, an association with an immunocompromised state has been suggested. We report a case of a Mycoplasma haemofelis–like infection in an HIV-positive patient co-infected with Bartonella henselae.

1 March 2011 in Revista Brasileira de Parasitologia Veterinária
Verified
Journal Article
Open access
PDF file
Rafael Felipe da Costa VieiraRafael Felipe da Costa Vieira
Rafael Felipe da Costa Vieira
Alexander Welker BiondoAlexander Welker Biondo
Alexander Welker Biondo
AGAna Marcia Sá Guimarães
Ana Marcia Sá Guimarães
ASAndrea Pires dos Santos
Andrea Pires dos Santos
RSRodrigo Pires dos Santos
Rodrigo Pires dos Santos
OVOdilon Vidotto
Odilon Vidotto
Ehrlichiosis is a disease caused by rickettsial organisms belonging to the genus Ehrlichia. In Brazil, molecular and serological studies have evaluated the occurrence of Ehrlichia species in dogs, cats, wild animals and humans. Ehrlichia canis is the main species found in dogs in Brazil, although E. ewingii infection has been recently suspected in five dogs. Ehrlichia chaffeensis DNA has been detected and characterized in mash deer, whereas E. muris and E. ruminantium have not yet been identified in Brazil. Canine monocytic ehrlichiosis caused by E. canis appears to be highly endemic in several regions of Brazil, however prevalence data are not available for several regions. Ehrlichia canis DNA also has been detected and molecularly characterized in three domestic cats, and antibodies against E. canis were detected in free-ranging Neotropical felids. There is serological evidence suggesting the occurrence of human ehrlichiosis in Brazil but its etiologic agent has not yet been established. Improved molecular diagnostic resources for laboratory testing will allow better identification and characterization of ehrlichial organisms associated with human ehrlichiosis in Brazil.

1 January 2009 in Revista Brasileira de Parasitologia Veterinária
Verified
Journal Article
Open access
Alexander Welker BiondoAlexander Welker Biondo
Alexander Welker Biondo
ASAndrea Pires dos Santos
Andrea Pires dos Santos
AGA. M. S. Guimarães
A. M. S. Guimarães
Rafael Felipe da Costa VieiraRafael Felipe da Costa Vieira
Rafael Felipe da Costa Vieira
OVO. Vidotto
O. Vidotto
JMJ. B. Messick
J. B. Messick
Recent studies have been conducted in Brazil using molecular techniques for the detection of hemotrophic mycoplasmas in several mammals. In domestic cats, Mycoplasma haemofelis, "Candidatus M. haemominutum", and "Candidatus M. turicensis" infections have been identified. These species have also been found in free-ranging and captive neotropical felid species. Two canine hemoplasmas, Mycoplasma haemocanis and "Candidatus Mycoplasma haematoparvum", have been identified in dogs. In commercial swine populations, Mycoplasma suis was found to be highly prevalent, especially in sows. Moreover, novel mycoplasma species have been identified in Brazilian commercial pigs and domestic dogs. A hemoplasma infection in a human patient infected with the human immunodeficiency virus (HIV) was also recently documented. In conclusion, hemoplasma species are common and important infectious agents in Brazil. Further studies should be conducted to better understand their impact on pets, production animals, and wildlife fauna, as well as their role as zoonotic agents, particularly in immunocompromised patients.

10 May 2011 in PLOS ONE
Verified
Journal Article
Open access
PDF file
AGAna M. S. Guimarães
Ana M. S. Guimarães
ASAndrea Pires dos Santos
Andrea Pires dos Santos
PSPhillip SanMiguel
Phillip SanMiguel
TWThomas Walter
Thomas Walter
JTJorge Timenetsky
Jorge Timenetsky
JMJoanne B. Messick
Joanne B. Messick
Mycoplasma suis, the causative agent of porcine infectious anemia, has never been cultured in vitro and mechanisms by which it causes disease are poorly understood. Thus, the objective herein was to use whole genome sequencing and analysis of M. suis to define pathogenicity mechanisms and biochemical pathways. M. suis was harvested from the blood of an experimentally infected pig. Following DNA extraction and construction of a paired end library, whole-genome sequencing was performed using GS-FLX (454) and Titanium chemistry. Reads on paired-end constructs were assembled using GS De Novo Assembler and gaps closed by primer walking; assembly was validated by PFGE. Glimmer and Manatee Annotation Engine were used to predict and annotate protein-coding sequences (CDS). The M. suis genome consists of a single, 742,431 bp chromosome with low G+C content of 31.1%. A total of 844 CDS, 3 single copies, unlinked rRNA genes and 32 tRNAs were identified. Gene homologies and GC skew graph show that M. suis has a typical Mollicutes oriC. The predicted metabolic pathway is concise, showing evidence of adaptation to blood environment. M. suis is a glycolytic species, obtaining energy through sugars fermentation and ATP-synthase. The pentose-phosphate pathway, metabolism of cofactors and vitamins, pyruvate dehydrogenase and NAD+ kinase are missing. Thus, ribose, NADH, NADPH and coenzyme A are possibly essential for its growth. M. suis can generate purines from hypoxanthine, which is secreted by RBCs, and cytidine nucleotides from uracil. Toxins orthologs were not identified. We suggest that M. suis may cause disease by scavenging and competing for host' nutrients, leading to decreased life-span of RBCs. In summary, genome analysis shows that M. suis is dependent on host cell metabolism and this characteristic is likely to be linked to its pathogenicity. The prediction of essential nutrients will aid the development of in vitro cultivation systems.

30 May 2019 in PLOS Neglected Tropical Diseases
Verified
Journal Article
Open access
PDF file
LKLouise B Kmetiuk
Louise B Kmetiuk
FKFelipe Krawczak
Felipe Krawczak
FMFernanda P Machado
Fernanda P Machado
IPIgor A D Paploski
Igor A D Paploski
TMThiago F Martins
Thiago F Martins
Alexander Welker BiondoAlexander Welker Biondo
Alexander Welker Biondo
Rickettsia bacteria are responsible for diseases in humans and animals around the world, however few details are available regarding its ecology and circulation among wild animals and human populations at high transmission risk in Brazil. The aim of this study was to investigate the occurrence of ticks and Rickettsia spp. in wild boars, corresponding hunting dogs and hunters. Serum samples and ticks were collected from 80 free-range wild boars, 170 hunting dogs and 34 hunters from southern and central-western Brazil, from the Atlantic Forest and Cerrado biomes, respectively, between 2016 and 2018. Serum samples were tested by indirect immunofluorescent-antibody assay (IFA) to detect IgG antibodies against Rickettsia rickettsii, Rickettsia parkeri, Rickettsia bellii, Rickettsia rhipicephali and Rickettsia amblyommatis. Tick species were identified by morphological taxonomic keys, as previously described. A total of 164 ticks including A. sculptum, A. brasiliense and A. aureolatum were tested in PCR assays for Spotted Fever Group (SFG) Rickettsia spp. A total of 58/80 (72.5%) wild boars, 24/170 (14.1%) hunting dogs and 5/34 (14.7%) hunters were positive (titers ≥ 64) to at least one Rickettsia species. A total of 669/1,584 (42.2%) ticks from wild boars were identified as Amblyomma sculptum, 910/1,584 (57.4%) as Amblyomma brasiliense, 4/1,584(0.24%) larvae of Amblyomma spp. and 1/1,584 (0.06%) nymph as Amblyolmma dubitatum. All 9 ticks found on hunting dogs were identified as Amblyomma aureolatum and all 22 ticks on hunters as A. sculptum. No tested tick was positive by standard PCR to SFG Rickettsia spp. The present study was the concomitant report of wild boar, hunting dog and hunter exposure to SFG rickettsiae agents, performed in two different Brazilian biomes. Wild boar hunting may increase the risk of human exposure and consequently tick-borne disease Wild boars may be carrying and spreading capybara ticks from their original habitats to other ecosystems. Further studies can be required to explore the ability of wild boars to infecting ticks and be part of transmission cycle of Rickettsia spp. The present study reported serological findings and molecular assays of Rickettsia spp and ticks of wild boars, simultaneous to their correspondent hunting dogs and hunters. Seropositivity for Rickettsia spp. was higher in wild boars when compared to dogs and humans but was similar between dogs and humans. Despite Rickettsia spp. prevalence was statistically higher in southern than central-western Brazil for wild boars, no significance was observed in hunting dogs and hunters. For the first time, A. sculptum ticks were founded in wild boars from the subtropical climate of southern Brazil. Despite human beings have been considered less exposed to ticks (and therefore rickettsiae) than animals, specific human activities such as wild boar hunting may increase the risk of exposure and consequently tick-borne disease. Wild boars may be carrying and spreading capybara ticks from their original habitats to other ecosystems. These results may provide important findings for public action planning to prevent neglected vector-borne diseases in overlapping areas of wild boars, hunting dogs and hunters. Further studies can be required to explore the ability of wild boars to infecting ticks and be part of transmission cycle of Rickettsia spp.

1 September 2011 in Veterinary Microbiology
Verified
Journal Article
Closed access
AGAna Laura Grazziotin
Ana Laura Grazziotin
ASAndrea Pires dos Santos
Andrea Pires dos Santos
AGAna M. S. Guimarães
Ana M. S. Guimarães
AMAhmed Mohamed
Ahmed Mohamed
ZCZalmir Silvino Cubas
Zalmir Silvino Cubas
JMJoanne Belle Messick
Joanne Belle Messick