One Health in The Brazilian Western Amazon: Helminths in Native Fish and The Food Change of The Puruborá People

The aim was to approach an analysis of fish parasites in the Manoel Correia and Caio Espínola Rivers, which border the Aldeia Aperoi, and the report of the Puruborá People on the use of fish as animal protein. Twenty-one fish were collected in the dry season and 15 in the rainy season, totaling 36 specimens, which dissipated cestodes, acanthocephala and nematodes encysted in the musculature, preventing their consumption. Six residents of Aldeia Aperoi were interviewed. The circulation of parasites with zoonotic potential was identified in fish native to the Manoel Correia and Caio Espínola rivers, which border the Aldeia Aperoi, in the Western Amazon of


Introduction
Foodborne diseases (FBD) are infections or intoxications caused by eating contaminated food and/or water that have an impact on public health 1 . There are more than 250 types of FDB, and among them, those caused by parasitic infections due to fish consumption 2,3 .
The identification of parasitic diseases associated with the consumption of fish in Brazil is not easy, as most are not mandatory to report. Additionally, due to the low severity of the symptoms and the little knowledge by the doctors on the subject, they go unnoticed 4 . Thus, the most appropriate approach to parasitic diseases in fish is in the context of one health, since ecological studies on freshwater fish parasites provide relevant data on the seasonality and susceptibility of the parasites and their hosts, while analyze the health status of fish, streams and indigenous people who use this source of protein as food, in addition to the quality of the water. Thus, there are answers regarding the imbalance of the environment and the possibility of zoonoses due to the consumption of parasitic fish 5 .
Fish are, worldwide, an important protein source for thousands of people; however, for indigenous and riverine people it does not only represent the food and economic base, but also the maintenance of customs and culture 6 , especially for groups that settled on the banks of rivers, as occurs in the Amazon. The Puruborá People on the state of Rondônia in the Western Amazon of Brazil is such an example.
The history of colonization and occupation of the state of Rondônia (whichwas created only in 1981), located in the western Brazilian Amazon, is full of disorderly occupations and invasions of forest spaces and indigenous lands. This is the result of several economic cycles: rubber, wood and precious metals. In all cycles, the destruction or extinction of indigenous ethnic groups was observed 7 .
The Puruborá people had their first contact with non-indigenous people in 1909, and from that moment on they began deconstructing themselves as a people/ethnicity. They suffered great miscigenation with the rubber tappers who occupied the area during the rubber cycle. Thus, the Puruborá people were expelled from their lands, and expropriated from their language and culture and were almost decimated by diseases 8 .
Over the years they spread throughout the territory of Rondônia and for survival, they became an ethnic group with mixed race with blacks, whites, other indigenous peoples, in addition to Bolivians and quilombolas 8,9 . At the end of the 1990s the Puruborá were forced to start a new life on the banks of the BR-429, between the municipalities of Seringueiras and São Francisco do Guaporé, in Rondônia, which was later known as Aperoi Village 10 . Currently, the Puruborá People try to recover their identity, language and customs 11 . However, the eating behavior based on fish protein has been modified due to environmental changes caused, among others, by damming and contamination of rivers, loss of ichthyofauna diversity and increase of parasites in fish. In relation to the latter, it is known that parasites can be bioindicators of environmental balance, since they present advantages over other organisms, such as rapid response to environmental changes, due to the interdependence of the ecological networks in which they live 12  People's narratives on the use of fish as animal protein.

Identification of parasites
In Aperoi Village fishing can be performed by men and women, and also by children, when accompanied by adults.
We identified in this work the following parasites: of the genus Eustrongylides sp., third-instar larvae of Contracaecum sp., metacercaria of Ithyoclinostomum sp. and Neoechinorhynchus buttnerae (Table 1).

Transcript of interviews with indigenous residents of Aperoi village
We selected relevant excerpts regarding the dietary change in the use of fish protein in the past ten years in Aperoi Village. The researchers respected the way of speaking and the common name that the interviewees gave to objects and fish.
Researcher asked: Good morning! Could you please tell me how the fishes and the Manoel Correia and Caio Espínola rivers were like about ten years ago?

Interviewee 1:
Regarding what we eat, we used a lot of fish. From about ten years ago our river has changed very much in the aspect of water volumebecause before our river didn't get dryso it was plenty of fish all the time and there wasn't a lot of fisherman.
But then the number of fishermen increased and the river is now drying up. It is very harmful for the people who need this food, as we believe that some worms in fish are caused by the lack of water.
When we catch and open the traíra it has worms. We normally take it out and consume it anyway, but when it has a lot of worms, we have to throw it away. The same thing is with the peacock bass, also with lots of worms during the dry season. But I don't know if it's because the water is still when the river is drying up, or if it's something that it uses as food. For example, we fish the pacu (Piaractus mesopotamicus) with longline (a heavy fishing line that may be many miles long and that has baited hooks in series) during the flood season, but it also comes with many worms. We don't know whether it is good or bad to eat these fish, but the river is a very essential source of food for us, the Puruborá, it is really important. People used to eat some of them and now they don't eat because of the worms. Nobody buys peacocks and traíras because of the worms. People buy more piau, which is now without worms.
However, there was piau that had worms in the belly, but without getting into the skin, but I think there will be later on. And that affects sales of peacock bass: nobody wants to buy it because of the worms. I sell pacu more because it eats fruits; but in a while they will also have worms as even in fruits, we may find worms. for two years in the São Miguel River, which is almost our river, one is an affluent of the other. There was a lot of fish mortality, and in our river, there was also fish mortality. People believe that it is because of these poisons thrown in the fields and there are many streams here that throw these contaminated waters into our river.
Our river is not so big here, so we can see this all happening.
Researcher asked: Are there any further considerations about the fishes, the river and the parasites that you would like to share?
Interviewee 6: Well, if they stopped using poison, I think these worms would decrease. We believe that poison and felling trees are making fish sick. There will come a time when we will not eat fish anymore, no one will want to eat a fish full of worms, people will no longer call friends to eat fish for when they try it, worms will appear and they'll say you gave them fish with worms to eat. One day we'll eat only meat. However, it is common to consume raw fish fillet with lemon and salt during fishing 15 , not only by indigenous people and riverine people, but by sport fishing (personal communication).
The presence of Eustrongylides sp. in the musculature of the fish it gives a disgusting aspect, due to the large size of the larvae, reddish color and quantity found (as in the present study). It is important to emphasize that when fish are low (of parasites) they remove and ingest the meat (narrative of the interviewees). This highlights the importance of health education to the population regarding the risks of eating raw or undercooked fish. In reports of human infection, it was possible to observe that the larvae penetrate the digestive tract wall, causing perforation and severe pain 21 .
In addition, Contracaecum sp., a parasite of the Anisakidae family, also has zoonotic potential and has been frequently described in native fish in Brazil 22  Contracaecum larvae were of severe and painful condition in humans 26 .
There has been no epidemiology work carried out at the Aperoi Village to identify possible cycles of Eustrongylides and Contracaecum within the human community yet. Accordingly, no case of illness has been reported without identifying the primary cause. However, as the signs of such parasitism are not specific, it can be inferred that if infection occurs in this population, it may go unnoticed. Another important point to make is that, due to the unpleasant aspect of parasites in the fish meat, it turns to be disagreeable for consumption, consequently reducing its possibility and therefore, of infection.
Another parasite identified in this study was Ithyoclinostomum sp., which is a digenetic trematode, and has no reports of zoonotic potential, but that the presence of cysts containing the metacercariae of this parasite causes disgust 27 . This parasite has been found from north to south of Brazil 28,29 and studies on the parasite-host relationship

Ethics and procedures
This study was approved by the methods involving humans' subjects and were performed in accordance with relevant guidelines and criteria according to Research The digestive tract was separated into portions and its contents were washed with 0.9% saline solution for analysis under a stereomicroscope to collect the parasites.
The nematode helminths, larvae and cysts were conditioned in 70% alcohol and the Acanthocephali were fixed in 5% hot formalin to distend the proboscis. The identification of the parasites was based on specific bibliographic consultation according to the findings and the methodologies described by Thatcher 34 , Martins 35 and Eiras et al. 36 .

Interviews with Puruborá indigenous people in Aperoi Village
We developed this investigation according to the research precepts described by Gil 37 , as an exploratory study based on interviews. The researcher, also belonging to the