Journal of Environment and Earth Science ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online) Vol.4, No.2, 2014
www.iiste.org
Prevalence of Diphyllobothrium Latum (Fish Tapeworm) in Fish I\in Ekiti State, Nigeria Adewole, S.O; Oguntoyinbo B.V; Agunbiade, R.O; and Ayeni S.K. Department of Zoology, Ekiti State University, P.M.B 5363, Ado-Ekiti, Ekiti State Nigeria. Abstract Studies on the prevalence of Diphyllobothrium latum (fish tapeworm) in fishes in ponds/ dams in Ekiti-State was carried out. Of the 1,000 fishes (Clarias gariepinus and Tilapia) collected and examined for Diphyllobothrium latum, 321 were infected representing 32.1%. Out of the 700 Clarias gariepinus examined for the Diphyllobothrium latum, 220 were infected giving 31.4% while out of the 300 Tilapia examined, 101 were infected with the Diphyllobothrium latum, which represent 33.7%. However, there was no significant difference (t = 22.17; p> 0.05) between Clarias gariepinus and Tilapia susceptibility to Diphyllobothrium latum. Measures aimed at eradicating/reducing the prevalence rate of the disease were highlighted. Keywords: Prevalence, Fish tapeworm, Clarias gariepinus, Tilapia and pond/dam Correspondence: Prof. S.O. Adewole, Ekiti State University, Faculty of Science, Department of Zoology, P.m.b 5363, Ado-Ekiti, Ekiti-State, Nigeria. Introduction Parasitic worms are among the most common cause of chronic infection in humans in developing countries. It is more common to be infected than not infectious thrives and persists in communities in need of better housing, clean water, appropriate sanitation, better access to health care, education and increased personal earning (Koch, 2008). Human diphyllobothriasis is a cosmopolitan fish-borne zoonosis caused by tapeworms of the genus Diphyllobothrium (Cestoda : Diphyllobothrides) (Shimizu et al, 2008). The fish tapeworm (Diphyllobothrium latum) is the largest parasite that infects humans. Human become infected when they eat raw or undercooked fresh water fish that contain tapeworm cysts. Immature eggs are passed out in faeces of mammalian host (the definite host) (Dick et al, 2007). After ingestion by a suitable freshwater crustacean such as copepod acidia develop into procercoid larvae. The procercoid develop into the infective stage larvae called plerocercoid. After the ingestion of the infected fish, the plerocercoids develop into immature adults and then into immature tapeworms in the small intestine (King, 2007). Diphyllobothriasis is an emerging infectious disease in certain part of the world where cultural practices involving eating raw or undercooked fish are being introduced. Therefore this study is designed to assess the prevalence of Diphyllobothrium latum in this part of the world. Materials and Methods The study was carried out in Ekiti-State which is located between longitude 4O 51 to 5O 451E and latitude O 1 7 15 to 8O 51N. The State is localed in the tropics and enjoys two distinct seasons which are rainy season (April - October) and dry season (November - March) with annual rainfall between 1,524 – 2,699mm. The relative humidity is above 80% with a temperature range of 21OC - 28OC. Inhabitants are mainly civil servants, farmers, petty traders and few migrant labourers. Samples of Clarias gariepinus and Tilapia were collected from five different towns viza viz Ado, Ire, Ikun, Ise and Omuo. After collections, samples were immediately transported to Zoology laboratory Ekiti State University, Ado-Ekiti for parasitological examination. A total of 1,000 fishes were collected with the breakdown of 700 Clarias gariepinus and 300 Tilapia respectively. Specimen were labeled A – Z according to the numbers of collections per day/sites. Samples were taken one after the other, laying ventrally in the dissecting way, the dorsal sides were symmetrically incised with the aid of surgical blade to expose the alimentary canals of the fishes. The gonads comprises on intestine, stomach and liver were carefully incised and detached with surgical blades. Each gonads (incised) were carefully clippered in Petri-dishes filled with prepared 10% Normal Saline for 20 minutes. After, the parasite (Diphyllobothrium latum) appeared on the surface of Normal Saline filled in a Petri-dish. Diphyllobothrium latum was carefully taken with dropper on glass slide and taken viewed under the binocular microscope. Other fishes were also examined by using the same method. Descriptive and inferential statistics were used to compare the susceptibility of Clarias gariepinus and Tilapia to diphyllobothriasis Results The result of this study showed that both Clarias gariepinus and Tilapia were susceptible to
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Journal of Environment and Earth Science ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online) Vol.4, No.2, 2014
www.iiste.org
Diphyllobothrium latum which causes diphyllobothriasis of the 1,000 fishes (Clarias gariepinus and Tilapia) collected and subjected to laboratory analysis, 321 were infected with Diphyllobothrium latum representing 32.1%. The breakdown of the result showed that out of 700 Clarias gariepinus examined for Diphyllobothrium latum, 220 were infected giving 31.4% while out of 300 Tilapia examined, 101 were infected with Diphyllobothrium latum representing 33.7%. However, there was no siginificant difference (t = 22.17; p > 0.05) between Clarias gariepinus and Tilapia susceptibility to infection. It is evident from Table 1 that Omuo-Ekiti recorded the highest prevalence of Diphyllobothrium latum infection in which 33 out of 70 Clarias gariepinus examined were infected representing 47.1% while the least prevalence was recorded in Ado-Ekiti in which 56 out of 200 examined were infected with Diphyllobothrium latum which represents 28%. In another development, table 2 showed that Ikun-Ekiti and Ise-Ekiti recorded the highest percentage prevalence of 36% respectively while the least percentage prevalence of 31.3% was recorded in Ado-Ekiti. Measures aimed at reducing the prevalence rate of the disease were included. Table 1: Samples of Clarias gariepinus used S/N Locations Samples Number Number infected with Infection rates examined Diphyllobothrium latum (%) Ado-Ekiti(Water Clarias 200 56 28% 1 works) Ire-Ekiti (Fish pond) Clarias 250 72 28.8% 2 Ikun-Ekiti (Ikun- Clarias 100 35 35.0% 3 dam) Ise-Ekiti Clarias 80 24 30.0% 4 (fish-pond) Omuo-Ekiti (fish Clarias 70 33 47.1% 5 pond) 700 220 31.4% Total Table 2: Samples of Tilapia Used S/N Locations Samples 1 2 3 4 5
Ado-Ekiti (Water-works) Ire-Ekiti (Fish pond) Ikun-Ekiti (Ikun Dam) Ise-Ekiti (Fish pond) Omuo-Ekiti (Fish pond) Total
Tilapia
Number examined 80
Number infected with Diphyllobothrium latum 25
Infection rates (%) 31.3%
Tilapia
70
24
34.3%
Tilapia
50
18
36.0%
Tilapia
60
21
36.0%
Tilapia
40
3
32.5%
300
101
33.7%
Discussion The epidemiology of Diphyllobothriasis has changed drastically from rural to urban arrears because of the rapid expansion of the transport system for fresh and frozen fish to meet the demand for seafood in healthy diets. The uninterrupted occurrence of Diphyllobothriasis in urban areas implies that the Diphyllobothrium latum (fish tapeworm) perpetuates its natural life cycle successfully between fish and its final host (Nakao et al, 2007). The occurrence of Diphyllobothrium latum in the study area showed that there was active transmission of Diphyllobothriasis. The high prevalence of Diphyllobothrium latum recorded in this study may due to lack of improvement in the standard of sanitation, poor management of ponds/dams, consumption of undercooked fish(es) and lack of publicity/awareness on the mode of transmission of Diphyllobothrium latum in these areas (Sampai et al, 2009). The inhabitants of both sexes and all ages in these area were equally exposed to Diphyllobothrium latum infection. Female were found with higher prevalence rate than male. This may be probably due to the fact female undergoes the hurdles of cooking and therefore usually eat undercooked fish whenever they are preparing stew/soup for household consumption. (Lianguno and Mauricio, 2008). The non-significant difference between Clarias gariepinus and Tilapia susceptibility to infection may be due to the fact that they both inhabit the same environment and they were subjected to the same environmental conditions, hence equal level of exposure and similarly, equal degree of susceptibility (Dupony et
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Journal of Environment and Earth Science ISSN 2224-3216 (Paper) ISSN 2225-0948 (Online) Vol.4, No.2, 2014
www.iiste.org
al, 2010). In view of the increased in the occurrence of the disease, measures to eradicate/reduce the disease should be intensified. These measure include improved standard of sanitation, deworming, health programme/public awareness to sensitize the inhabitants the mode of transmission and improve on the nutrition to Iron content by government through the provision of small emonuments to workers on monthly basis as well as through poverty alleviation program to the categories of people who are not government workers.
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