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Neotropical Helminthology
Neotropical Helminthology, 2026, vol. 20 (2), 247-257
ORIGINAL ARTICLE / ARTÍCULO ORIGINAL
GIARDIASIS OUTBREAK IN SITU SOUTHERN TAMANDUAS (TAMANDUA
TETRADACTYLA LINNAEUS, 1758) UNDERGOING REHABILITATION:
CLINICAL FINDINGS, THERAPEUTIC MANAGEMENT, AND PROGNOSIS
BROTE DE GIARDIASIS EN OSOS HORMIGUEROS MENORES (TAMANDUA
TETRADACTYLA LINNAEUS, 1758) IN SITU EN PROCESO
DE REHABILITACIÓN: HALLAZGOS CLÍNICOS, TERAPÉUTICOS
Y PRONÓSTICO
SURTO DE GIARDÍASE EM TAMANDUÁS-MIRINS (TAMANDUA
TETRADACTYLA LINNAEUS, 1758) IN SITU EM PROCESSO DE
REABILITAÇÃO: ACHADOS CLÍNICOS, TERAPÊUTICOS E PROGNÓSTICO
João Victor Batista dos Santos1,2*, Marcel Felipe Carvalho de Santana2,4, Júlia Sibelly Matos Santos2,4,
Shirley Maria Santos Passos3,4, Bianca Fontes Bomfi m3,4, Nythaelle Dantas de Moraes e Silva3,4,
André Mota Alves5, Katiúscia Ribeiro de Souza6, Lorena Gabriela Rocha Ribeiro3,4 &
Victor Fernando Santana Lima1,2,4
ISSN Versión Impresa 2218-6425 ISSN Versión Electrónica 1995-1403
DOI: https://doi.org/10.62429/rnh20262022197
Universidad Nacional
Federico Villarreal
Volume 20, Number 1 (Jan - Jun) 2026
Este artículo es publicado por la revista Neotropical Helminthology de la Facultad de Ciencias Naturales y Matemática, Universidad Nacional Federico
Villarreal, Lima, Perú auspiciado por la Asociación Peruana de Helmintología e Invertebrados Afi nes (APHIA). Este es un artículo de acceso abierto,
distribuido bajo los términos de la licencia Creative Commons Atribución 4.0 Internacional (CC BY 4.0) [https:// creativecommons.org/licenses/by/4.0/
deed.es] que permite el uso, distribución y reproducción en cualquier medio, siempre que la obra original sea debidamente citada de su fuente original.
1 Graduate Program in Parasitic Biology, Federal University of Sergipe, São Cristóvão, Sergipe, Brazil.
2 Laboratory of Veterinary Infectious Diseases, Federal University of Sergipe, São Cristóvão, Sergipe, Brazil.
3 Animal Pathology Laboratory, Federal University of Sergipe, São Cristóvão, Sergipe, Brazil.
4 Department of Veterinary Medicine, Federal University of Sergipe, São Cristóvão, Sergipe, Brazil.
5 Aquatic Mammals Foundation, Aracaju, Sergipe, Brazil.
6 Wild Animal Screening and Rehabilitation Center, Sergipe, Brazil.
* Correspondence author: E-mail: jvbatista2002@gmail.com
João Victor Batista dos Santos: https://orcid.org/0000-0003-4393-544X
Marcel Felipe Carvalho de Santana: https://orcid.org/0009-0001-8056-3166
Júlia Sibelly Matos Santos: https://orcid.org/0009-0000-5565-7147
Shirley Maria Santos Passos: https://orcid.org/0000-0001-6639-547X
Bianca Fontes Bomfi m: https://orcid.org/0009-0003-5388-2107
Nythaelle Dantas de Moraes e Silva: https://orcid.org/0009-0002-6351-1003
André Mota Alves: https://orcid.org/0000-0002-9150-5287
Katiúscia Ribeiro de Souza: https://orcid.org/0009-0003-4197-0396
Lorena Gabriela Rocha Ribeiro: https://orcid.org/0000-0003-3471-440X
Victor Fernando Santana Lima: https://orcid.org/0000-0002-7255-0664
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ABSTRACT
Giardia is an intestinal protozoan parasite responsible for parasitizing a wide range of vertebrates, with transmission
occurring through contaminated water and food containing cysts released by infected hosts. Given this context, the present
study aimed to describe an outbreak of giardiasis in three southern tamanduas (Tamandua tetradactyla Linnaeus, 1758)
undergoing rehabilitation in the state of Sergipe, Brazil, as well as the clinical and therapeutic aspects of this disease. A
male specimen that died abruptly, presenting anorexia, malnutrition, cachexia, and diarrheic feces, was submitted for
necropsy analysis at the Animal Pathology Department of the Federal University of Sergipe – São Cristóvão Campus.
Gastric content analysis, urinalysis, bone marrow smear, and fecal parasitological examination were performed, identifying
the presence of cysts and trophozoites of Giardia duodenalis Stiles, 1902. Subsequently, the other animals sharing the
same enclosure—a female and a male presenting diarrheic feces—were referred for clinical care at the Wildlife Animal
Sector of the Veterinary Hospital of the Federal University of Sergipe – São Cristóvão Campus. Complete blood count,
serum biochemistry, and fecal parasitological examinations were performed on both animals, revealing the presence of G.
duodenalis cysts. Treatment with Metronidazole, along with environmental and dietary management, was instituted. After
completion of treatment, the animals were re-evaluated, showing resolution of diarrheic episodes and improvement in
nutritional status, and a new fecal parasitological examination was conducted, with no G. duodenalis cysts or trophozoites
observed. is study revealed previously unreported clinical alterations associated with Giardia infection in this species,
as well as describing the therapeutic approach employed, contributing significantly to the medicine of xenarthrans.
Keywords: Clinical Signs – Cysts – Giardia – Trophozoites
RESUMEM
Giardia es un protozoo intestinal responsable de parasitar una amplia variedad de vertebrados, cuya transmisión ocurre a
través del agua y alimentos contaminados que contienen quistes liberados por hospedadores infectados. Dado este contexto,
el presente estudio tuvo como objetivo describir un brote de giardiasis en tres tamandúas del sur (Tamandua tetradactyla
Linnaeus, 1758) en proceso de rehabilitación en el estado de Sergipe, Brasil, así como los aspectos clínicos y terapéuticos
de esta enfermedad. Un ejemplar macho que murió abruptamente, presentando anorexia, desnutrición, caquexia y heces
diarreicas, fue sometido a un análisis de necropsia en el Departamento de Patología Animal de la Universidad Federal
de Sergipe – Campus São Cristóvão. Se realizaron análisis del contenido gástrico, análisis de orina, frotis de médula
ósea y examen parasitológico fecal, identificándose la presencia de quistes y trofozoítos de Giardia duodenalis Stiles,
1902. Posteriormente, los otros animales que compartían el mismo recinto —una hembra y un macho que presentaban
heces diarreicas— fueron remitidos para atención clínica al Sector de Animales Silvestres del Hospital Veterinario de la
Universidad Federal de Sergipe – Campus São Cristóvão. Se realizaron hemograma completo, bioquímica sérica y exámenes
parasitológicos fecales en ambos animales, revelando la presencia de quistes de G. duodenalis. Se instauró tratamiento
con metronidazol, junto con manejo ambiental y dietético. Después de completar el tratamiento, los animales fueron
reevaluados, mostrando resolución de los episodios diarreicos y la mejoría del estado nutricional, y se realizó un nuevo
examen parasitológico fecal, sin observarse quistes ni trofozoítos de G. duodenalis. Este estudio reveló alteraciones clínicas
previamente no descritas asociadas con la infección por Giardia en esta especie, además de describir el abordaje terapéutico
empleado, contribuyendo significativamente a la medicina de los xenartros.
Palabras clave: Giardia – Quistes – Signos clínicos – Trofozoítos
RESUMO
Giardia é um protozoário intestinal responsável pelo parasitismo de uma ampla variedade de vertebrados, cuja transmissão
ocorre por meio de água e alimentos contaminados com cistos eliminados por hospedeiros infectados. Diante desse contexto,
o presente estudo teve como objetivo descrever um surto de giardíase em três tamanduás-mirins (Tamandua tetradactyla
Linnaeus, 1758) em processo de reabilitação no estado de Sergipe, Brasil, bem como os aspectos clínicos e terapêuticos
dessa doença. Um espécime macho, que morreu de forma súbita, apresentando anorexia, desnutrição, caquexia e fezes
diarreicas, foi encaminhado para análise necroscópica no Departamento de Patologia Animal da Universidade Federal
de Sergipe – Campus São Cristóvão. Foram realizadas análises do conteúdo gástrico, urinálise, esfregaço de medula óssea
e exame parasitológico de fezes, sendo identificada a presença de cistos e trofozoítos de Giardia duodenalis Stiles, 1902.
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Posteriormente, os outros animais que compartilhavam o mesmo recinto — uma fêmea e um macho que apresentavam
fezes diarreicas — foram encaminhados para atendimento clínico no Setor de Animais Silvestres do Hospital Veterinário
da Universidade Federal de Sergipe – Campus São Cristóvão. Em ambos os animais, foram realizados hemograma, exames
bioquímicos séricos e exames parasitológicos de fezes, que revelaram a presença de cistos de G. duodenalis. Foi instituído
tratamento com metronidazol, associado a medidas de manejo ambiental e alimentar. Após a conclusão do tratamento, os
animais foram reavaliados, apresentando resolução dos episódios de diarreia e melhora do estado nutricional, e foi realizado
um novo exame parasitológico de fezes, no qual não foram observados cistos ou trofozoítos de G. duodenalis. Este estudo
revelou alterações clínicas ainda não relatadas anteriormente associadas à infecção por Giardia nessa espécie, além de descrever
a abordagem terapêutica empregada, contribuindo significativamente para o conhecimento da medicina de xenartros.
Palavras-chave: Cistos – Giardia – Sinais clínicos – Trofozoítos
INTRODUCTION
e superorder Xenarthra is represented by an ancestral
group of animals of South American origin, divided into
the orders Cingulata, represented by armadillos, and
Pilosa, which includes sloths and anteaters (Portillo et
al., 2022; Oliveira et al., 2023). Anteaters are a group of
placental mammals distributed into four species worldwide
(Oliveira et al., 2023), three of which occur in Brazil: the
silky anteater (Cyclopes didactylus Linnaeus, 1758), giant
anteater (Myrmecophaga tridactyla Linnaeus, 1758), and
southern tamandua (Tamandua tetradactyla Linnaeus,
1758) (Bertassoni et al., 2022).
Present in all Brazilian biomes, the southern tamandua
(T. tetradactyla), also known as the collared anteater, is an
obligate insectivore native to South America (Oliveira et al.,
2023). ese animals are discreet and nocturnal, possessing
a prehensile tail and short, dense fur with dark-brown and
golden-white coloration (Portillo et al., 2022). ey exhibit
regional dimorphism, with northern populations presenting
darker fur and longer bodies, snouts, and ears; Atlantic Forest
populations displaying lighter fur and a more defined “vest”;
and Cerrado populations showing a more golden coloration
(Bertassoni et al., 2022; Oliveira et al., 2023).
Giardia (Kunstler, 1882) is an intestinal protozoan
with significant impact on a wide range of vertebrates,
including birds, amphibians, reptiles, humans, and wild
and domestic mammals (Fehlberg et al., 2021; Gil et al.,
2025). Its dissemination mainly occurs through waterborne
transmission and contaminated food containing cysts shed
by infected hosts (Procesi et al., 2022). Giardia spp. cysts
have been reported in different mammalian species from
the families Atelidae, Canidae, Cricetidae, Didelphidae,
Felidae, and Procyonidae inhabiting the North, Northeast,
South, and Southeast regions of Brazil (Pantoja et al.,
2017; Barbosa et al., 2019; Fehlberg et al., 2021; Lignon
et al., 2025).
e genus Giardia is divided into the species G. agilis
(Kunstler, 1882) in amphibians, G. ardeae (Erlandsen,
1990) and G. psittaci (Erlandsem & Bemrick, 1987) in
birds, G. microti (Christiansen, 1915), G. muris (Grassi,
1879), and G. cricetidarum (Waldheim, 1817) in rodents, G.
duodenalis (Stiles, 1902) in vertebrates and humans, and G.
paramelis (Hillman, 2016) in Australian marsupials (Dixon,
2021; Tawana et al., 2022; Echeverry et al., 2025). Fecal
parasitological examinations are essential for the diagnosis
of gastrointestinal protozoa in captive animals, as these
agents are associated with alterations in the digestive system
(Liu et al., 2021). Species such as G. duodenalis present
a broad host range and zooanthroponotic and zoonotic
transmission cycles, favoring outbreaks associated with
cyst-contaminated sources, especially water, particularly in
Wildlife Screening Centers (CETAS) located near urban
centers (Barbosa et al., 2019; Gil et al., 2025).
Given the need for studies addressing the epidemiological
aspects, clinical alterations, and therapeutic protocols in
captive xenarthrans affected by gastrointestinal protozoa,
the present study aimed to describe an outbreak of giardiasis
in southern tamanduas (T. tetradactyla) and their respective
clinical and therapeutic aspects in the state of Sergipe,
Northeastern Brazil.
MATERIALS AND METHODS
An outbreak of giardiasis affecting three southern tamanduas
(T. tetradactyla) was identified at the Wildlife Screening
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Center (CETAS) located in the state of Sergipe, Brazil.
e animals were attended by the team of the Veterinary
Teaching Hospital of the Federal University of Sergipe –
São Cristóvão Campus (HVU-UFS). All individuals had
been maintained at the rehabilitation center for more
than one year, receiving a diet based on vegetables, with
a previous history of deworming and vaccination. At the
Animal Pathology Laboratory of the Federal University of
Sergipe – São Cristóvão Campus, fecal, urine, bone marrow
samples, hemoparasites and inclusion bodies, hematological
and serum biochemical samples from southern tamanduas
were collected for clinical analyses.
Ethical aspects: Submission of the present study for
review by an Ethics Committee was not required. is is
a descriptive report of three clinical cases involving animals
treated concurrently at the HVU-UFS.
RESULTS
e outbreak began with an approximately 8-month-old
male (Case 1) presenting with anorexia and diarrhea,
progressing to death within less than 24 h after the onset
of clinical signs. e animal was referred for necropsy
at the Animal Pathology Laboratory of the Federal
University of Sergipe – São Cristóvão Campus, where
fecal, urine, and bone marrow samples were collected for
clinical analyses. Urinalysis revealed light-yellow and clear
urine (RI: Straw yellow – Citrine yellow), with glycosuria
(++++; RI: +-), proteinuria (+++; RI: Negative), pH 7.0
(RI: 6,0-8,0), specific gravity of 1.020 (RI: 1.012-1.028),
bacteriuria (Positive; RI: Negative-Rare), hematuria (1-
3; RI: Rare), and leukocyturia (1-3; RI: Rare) (Reisfeld
et al., 2013).
e bone marrow sample was negative for hemoparasites
and inclusion bodies. Fecal content analyzed by direct
examination and the Willis-Mollay sucrose flotation
technique revealed, under 100× and 400× magnification,
oval structures containing four nuclei measuring 8–12 ×
7–10 µm and bilaterally symmetrical pyriform structures
measuring 12–15 × 5–9 µm, compatible with G. duodenalis
cysts and trophozoites, respectively, with approximately 20
cysts per field (Figures 1 and 2).
According to these findings, the other two rescued southern
tamanduas (T. tetradactyla) sharing the same enclosure were
referred for clinical evaluation at the Wildlife Medicine
Sector of HVU-UFS on the following day. ese included
a juvenile female (Case 2), weighing 3.700 kg, and a young
male (Case 3), weighing 3.200 kg, both undergoing
rehabilitation at CETAS.
Figure 1. Location of the region, state, and municipality where the giardiasis outbreak in anteaters occurred.
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Physical examination revealed bloody perianal diarrhea
and abdominal gas accumulation upon palpation in
both animals. Hematological and serum biochemical
alterations were observed. Case 2 presented erythrocytosis,
polycythemia, neutropenia, mild leukocytosis due to
lymphocytosis, elevated alkaline phosphatase (ALP),
hyperalbuminemia, and hyperglobulinemia. Case 3 showed
plasma hypoproteinemia, eosinopenia, lymphopenia,
leukocytosis due to neutrophilia with left shift, low
alanine aminotransferase (ALT) levels, hyperproteinemia,
hyperalbuminemia, and azotemia (Tables 1 and 2).
Figure 2. Giardia duodenalis cysts (arrow) observed in a fecal sample from a southern tamandua (Tamandua tetradactyla).
Table 1. Hematological profile of southern tamandua (Tamandua tetradactyla) specimens, Case 2 and Case 3.
Erythrogram Reference Case 2 Case 3
Result Result
Erythrocytes (x106/
µL) 2.63 – 3.67 3.87 2.99
Hemoglobin (g/dL) 9.46 – 12.0 14.2 10.9
Hematocrit (%) 31.5 – 38.1 44.6 35
MCV (fl) 99.8 – 132 115.3 117
MCH (pg) 31.0 – 40.0 36.8 36.4
MCHC (%) 27.5 – 34.7 31.9 31.2
TP (g/dL) 8.5 – 9.3 9.0 8,0
Platelets (x103/ µL) 180 – 370 - 298
Leukogram Case 2 Case 3
RR (%) RA RR* (%) RA* RR* (%) RA*
Leukocytes (/µL) - 5790 – 10340 - 11330 - 10770
Band Neutrophils 0 0 0 0 4 431
(Continúa Table 1)
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Fecal samples from both patients were collected and
submitted for parasitological examination using the same
methodology described for Case 1, revealing a high burden
of G. duodenalis cysts. e therapeutic protocol consisted
of Metronidazole administration (15 mg/kg/PO/SID)
for five days, in addition to enclosure disinfection and
environmental and dietary management adjustments.
After seven days, the animals underwent a new clinical
evaluation, demonstrating improved activity levels, absence
of diarrhea, and feces with normal appearance for the
species. Furthermore, no G. duodenalis cysts or trophozoites
were detected in fecal parasitological examinations using
direct examination and Willis-Mollay sucrose flotation.
DISCUSSION
e present study describes an outbreak of giardiasis
affecting three southern tamanduas (T. tetradactyla)
undergoing rehabilitation at a Wildlife Screening Center
(CETAS) in the state of Sergipe, Brazil, with one of the
animals progressing to death.
G. duodenalis is considered the only species with zoonotic
potential capable of infecting domestic and wild animals
(Al-Joubouri & Al-Awadi, 2023; Gil et al., 2025). Parasites
of this genus play an important role in the population
dynamics of wild species, directly interfering with
phenotypic and genetic diversity, as well as with the clinical
aspects of their hosts (Lignon et al., 2025). Infections by
Giardia in myrmecophagids such as M. tridactyla and T.
tetradactyla have been reported in countries including
Brazil, China, and Poland (Pencheva, 2013; Liu et al.,
2021). Affected animals may exhibit clinical signs such as
lethargy, anorexia, malabsorption, weight loss, impaired
growth, and acute or chronic diarrhea, either continuous
or intermittent, as observed in the three anteaters described
in the present study (Tangtrongsup et al., 2019; Nahavandi
et al., 2025) (Figure 3).
Previous studies have demonstrated the influence of
giardiasis on glucose and lipid metabolism, with infected
hosts presenting hyperglycemia and dyslipidemia (Al-
Joubouri & Al-Awadi, 2023; Ribeiro et al., 2025). e
glycosuria observed in the urinalysis of T. tetradactyla that
progressed to death may be associated with inhibition of
insulin activity caused by protozoan metabolites, resulting
Segmented
Neutrophils 39 – 57 2620 – 4980 17 1926 85 9155
Basophils 0 0 0 0 0 0
Eosinophils 4-8 220 – 680 3 340 0 0
Lymphocytes 35 – 53 2240 – 5060 79 8951 9 969
Monocytes 1 – 3 70 – 220 1 113 1 215
(Continúa Table 1)
MCV: Mean Corpuscular Volume
MCH: Mean Corpuscular Hemoglobin
MCHC: Mean Corpuscular Hemoglobin Concentration
TP: Total Protein
RR: Relative Reference Range
RA: Absolute Reference Range
RR*: Relative Result
RA*: Absolute Result
Table 2. Serum biochemical profile of southern tamandua (Tamandua tetradactyla) specimens, Case 2 and Case 3.
Serum Biochemistry Reference Unit Case 2 Case 3
Result Result
Aspartate Aminotransferase (AST/SGOT) 19 – 85 U/L 24 20
Alanine Aminotransferase (ALT/SGPT) 50 – 90 U/L 67 45
Alkaline Phosphatase (ALP) 11 – 60 U/L 104 29
Total Protein (TP) 6.16 – 7.09 g/dL 9.3 8.7
Albumin 1.01 – 1.82 g/dL 3.3 3.1
Globulin 5.02 – 5.8 g/dL 6.0 5.6
Albumin: Globulin Ratio (A: G Ratio) - - 0.55 0.55
Urea 42.0 – 67.0 mg/dL 60.1 96.3
Creatinine 0.36 – 1.16 mg/dL 1.01 1.13
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in increased serum glucose levels (Klimczak et al., 2024).
Furthermore, according to Ribeiro et al. (2025), giardiasis
may significantly impact hosts with metabolic disorders,
since hyperglycemia associated with dyslipidemia stimulates
pro-inflammatory mechanisms, increasing insulin resistance
and inhibiting insulin secretion.
Figure 3. Life Cycle of Giardia duodenalis in Myrmecophagids and Humans.
Case 2 presented erythrogram alterations characterized by
increased erythrocyte count, hemoglobin concentration,
and hematocrit values. ese findings are indicative of
more viscous and concentrated blood as a consequence of
dehydration, resulting in plasma volume reduction and
erythrocyte concentration (Song et al., 2020). Animals
affected by giardiasis may develop intestinal malabsorption
of fluids and electrolytes due to structural alterations of
intestinal microvilli caused by parasitism (Pinheiro et al.,
2014; Ragbetli et al., 2014; Boucard et al., 2021; Ribeiro
et al., 2025).
On leukogram evaluation, the same animal presented
leukocytosis due to lymphocytosis and neutropenia. Similar
findings were reported in an experimental study involving
rats with giardiasis, in which an increase in circulating
lymphocytes was observed (Abo-Zaid & Hamdi, 2022).
It is well established that parasitic infections increase the
number of circulating B and T lymphocytes in response to
parasitism (Serradell et al., 2018; Maertens et al., 2021).
In particular, T lymphocytes are responsible for producing
lymphokines that stimulate the migration of phagocytic
cells to inflammatory sites, whereas B lymphocytes play an
important role in immunoglobulin production (Garzon et
al., 2021; Abo-Zaid & Hamdi, 2022).
In the leukogram of Case 3, leukocytosis associated with
neutrophilia and left shift was observed, indicating a
regenerative inflammatory response. Such alterations may
indicate inflammatory processes intrinsically related to
intestinal inflammation caused by the protozoan infection
(Al-Joubouri & Al-Awadi, 2023; Klimczak et al., 2024).
High intestinal parasitic burdens of Giardia spp. are
responsible for inducing inflammatory processes as a result
of structural damage and shortening of intestinal microvilli,
enterocyte exfoliation, and peripheral membrane lesions
of the intestinal epithelium (Benchimol, 2020; Boucard
et al., 2021).
Experimental studies previously conducted in Mongolian
gerbils (Meriones unguiculatus Edwards, 1867) have
investigated the influence of giardiasis on metabolism
and basal enzyme levels (Araújo et al., 2008; Ribeiro et al.,
2025). A mild and nonspecific increase in ALT has been
described, generally associated with lesions in organs other
than the liver, excluding hepatic involvement (Gil et al.,
2025). In contrast, hypoalanine aminotransferasemia was
observed in Case 3 in the present study. Increased ALP
levels were observed in Case 2. ALP is an enzyme present in
biliary duct cells, bones, placenta, and intestines. Enterocyte
damage resulting from parasitism within intestinal crypts,
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Batista dos Santos et al.
causing hyperplasia and increased epithelial cell mitosis,
may lead to elevated circulating levels of this enzyme (Gil
et al., 2025).
Additionally, similarly to previous experimental studies,
hyperalbuminemia was observed in both animals. Increased
albumin levels are expected due to enhanced protein
catabolism resulting from the inflammatory response
associated with giardiasis (Gil et al., 2025). Elevated
serum protein levels are intrinsically related to increased
immunoglobulin synthesis, also contributing to increased
total protein concentrations and elevated globulin levels,
as observed in Case 2 (Shima et al., 2022; Cagnasso et al.,
2023).
e occurrence of azotemia in the biochemical profile,
associated with increased urea levels, has been reported
as a consequence of reduced glomerular filtration rate
caused by dehydration and hypovolemia (Ragbetli et
al., 2014). Increased urea concentrations have also been
reported in dogs affected by giardiasis due to gastrointestinal
hemorrhagic processes caused by parasitism (Safrany et al.,
2023). Furthermore, intestinal disorders such as diarrhea,
observed in the T. tetradactyla from Case 3, may induce
electrolyte imbalance, consequently increasing renal
biomarkers such as urea and creatinine (Ragbetli et al.,
2014; Al-Joubouri & Al-Awadi, 2023).
Eosinophilia is generally considered a common finding
in parasitic infections caused by helminths and protozoa,
since eosinophils actively participate in direct parasite
elimination (Ofori et al., 2025). Contrary to the findings
reported in an experimental study involving albino rats with
giardiasis conducted by Abo-Zaid & Hamdi (2022), which
described eosinophilia associated with both protozoan
infection and hypersensitivity reactions leading to histamine
release, eosinopenia was observed in Case 3. According
to Jasim (2020), reduced eosinophil counts may occur
because these cells actively migrate to tissues affected by
the protozoan, particularly the intestine, decreasing their
concentration in circulation while increasing their presence
at the infection site.
As demonstrated in the present study, there is still a limited
number of investigations addressing the epidemiological
and clinical aspects of Giardia infection in captive
mammals maintained in conservation parks, zoos, and
rehabilitation centers (Liu et al., 2021; Nahavandi et al.,
2025). Even in controlled environments, such facilities
may favor maintenance of the epidemiological cycle due
to the availability of hosts from different species and direct
transmission among confined animals (Kamel & Abdel-
Latel, 2021; Esteban-Sánchez et al., 2025). In addition,
factors such as captivity-related stress, high animal density,
and poor enclosure sanitation have been identified as
contributing factors increasing susceptibility and exposure
to infection (Šmit et al., 2023; An et al., 2024).
e adoption of biosecurity and biosafety strategies aimed
at preventing Giardia infections is considered essential and
has been increasingly applied in wildlife rehabilitation
and conservation centers (Kamel & Abdel-Latel, 2021;
Esteban-Sánchez et al., 2025). e implementation of
feeding management protocols combined with sanitary
surveillance of food and water quality provided to captive
animals constitutes a fundamental measure for interrupting
the transmission cycle of the protozoan (Liu et al., 2021;
An et al., 2024). Furthermore, isolation and reduction
of contact between infected animals and other animals
or professionals, the establishment of quarantine areas
and internal zoning within conservation centers, as
well as regular enclosure cleaning and disinfection, are
recommended to minimize the risk of environmental
contamination (Kamel & Abdel-Latel, 2021; Liu et al.,
2021; Esteban-Sánchez et al., 2025).
e present study describes an outbreak of giardiasis
affecting three southern tamanduas (T. tetradactyla)
undergoing rehabilitation at a Wildlife Screening Center
(CETAS) in the state of Sergipe, Brazil. Novel clinical
alterations associated with infection in this species were
identified, along with the therapeutic management adopted,
thereby contributing significantly to the field of xenarthran
medicine. Furthermore, the importance of implementing
rigorous biosafety and biosecurity protocols during wildlife
rehabilitation is emphasized to prevent outbreaks caused
by protozoa of this genus, limit their dissemination among
animals, and avoid potential losses associated with the
parasite.
Author contributions: CRediT (Contributor Roles
Taxonomy)
JVBS = João Victor Batista dos Santos
MFCS = Marcel Felipe Carvalho de Santana
JSMS = Júlia Sibelly Matos Santos
SMSP = Shirley Maria Santos Passos
BFB = Bianca Fontes Bomfim
NDMS = Nythaelle Dantas de Moraes e Silva
AMA = André Mota Alves
KRS = Katiúscia Ribeiro de Souza
LGRR = Lorena Gabriela Rocha Ribeiro
VFSL = Victor Fernando Santana Lima
255
Giardiasis outbreak in situ southern tamanduas
Neotropical Helminthology, Vol. 20, Nº2, jul - dec 2026
Conceptualization: JVBS, MFCS, JSMS
Data curation: JVBS, LGRR, VFSL
Formal Analysis: JVBS, MFCS, JSMS, SMSP, BFB,
NDMS
Funding acquisition: JVBS, VFSL
Investigation: JVBS, MFCS, JSMS, SMSP, BFB, NDMS,
KRS
Methodology: JVBS, MFCS, JSMS
Project administration: JVBS, AMA, KRS, LGRR, VFSL
Resources: KRS, LGRR, VFSL
Software: JVBS, AMA
Supervision: AMA, LGRR, VFSL
Validation: LGRR, VFSL
Visualization: JVBS, MFCS, JSMS, SMSP, BFB, NDMS
Writing – original draft: JVBS, MFCS, JSMS, SMSP,
BFB, NDMS
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Received June 27, 2026.
Accepted July 31, 2026.
Published online July 31, 2026
