Anisakis larvae found in Muscovy duck esophagus in Brazil
What it found
In 30 Muscovy ducks from Marajó Island, Brazil, 258 Anisakis larvae were found attached to the esophagus.
The authors say this is the first report of this parasite in Muscovy ducks in Brazil.
What they found
Animal and lab studies
Parasite found
A total of 258 nematodes were recovered from the esophagus of the ducks. All were identified as Anisakis third-stage larvae.
How many ducks
The prevalence was 10%, meaning 3 out of 30 ducks had the parasites. The number of larvae per bird ranged from 1 to 243.
Where they attached
The larvae were strongly fixed in the esophageal mucosa, the lining of the duck's esophagus.
Studies in people and animals
Possible risk to people
The authors say that ducks can act as paratenic hosts, meaning they can carry the larvae without being the final host. If people eat undercooked or raw duck meat, they could get infected, though the esophagus is not usually eaten.
Other findings
First report
This is the first record of Anisakis sp. parasitizing Muscovy ducks in Brazil. Previously, only Contracaecum genus had been reported in birds in Brazil.
What the authors conclude
“The zoonotic potential of these parasites must be considered, given the need for greater sanitary control in the consumption of these birds.”
Also in their conclusions
- They say the zoonotic potential of these parasites must be considered, given the need for greater sanitary control in the consumption of these birds.
- They alert the population of Marajó, who uses these birds as food, to the risks of acquiring an infection and how to avoid it.
- They note that although the lining of the esophagus is not an edible part of the duck, this nematode causes anisakiasis, so health surveillance should warn people.
How it was done
The authors wanted to identify the nematodes found in the esophagus of Muscovy ducks raised and sold in Soure, Marajó Island, and to discuss whether these parasites could pose a risk to people who eat the ducks.
They bought 30 Muscovy ducks (19 females and 11 males, 4 to 8 months old) from rural properties in Soure, Marajó Island, Brazil. The ducks were slaughtered on the farm, and their digestive organs were taken to the lab. The researchers examined the organs under microscopes and identified the nematodes they found.
What it can’t tell you
- This study looked at only 30 ducks from one area, so the findings may not apply to ducks elsewhere.
- The study found the parasite in the esophagus, but it did not test whether people actually got sick from eating these ducks.
- The authors did not find adult worms, only larvae, so they could not confirm the full life cycle in this setting.
Who paid
- Authors work at
- Instituto da Saúde e Produção Animal, Brasil; Instituto de Ciências Biológicas, Brasil
The paper
- Title
- First report of Anisakis sp. (Nematoda: Anisakidae) parasitizing Muscovy duck in Marajó Island, state of Pará, Brazil
- Type
- Study
- Evidence
- Studies in people · animals · lab
- Summarised from
- Full text
- Licence
- CC BY. Words in quotation marks are the authors’; the rest is our summary.
- Cite
- Carvalho EL, Santana RLS, Gonçalves EC, Pinheiro RHDS, Giese EG (2020). First report of Anisakis sp. (Nematoda: Anisakidae) parasitizing Muscovy duck in Marajó Island, state of Pará, Brazil. Revista brasileira de parasitologia veterinaria = Brazilian journal of veterinary parasitology. doi:10.1590/s1984-29612020015Free full textPubMed 32428178DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error