Abstract
Background
‘Cercarial dermatitis’ also known as swimmers itch (Skin allergies) is caused by a trematode parasite, Schistosoma which has two hosts - an invertebrate (snail) and a vertebrate (livestock, human being). Although the availability of both vector snails and pathogens at the selected site the Doon Valley in northern India has already been confirmed but there was a hazy picture of the disease, whether it is due to entrance of cercariae or due to wild variety of grass (Parthenium hysterophorus). The present study is an attempt to provide a way forward towards the vector snails and snail borne diseases in the study area.
Methods
Snail sampling and identification was done by applying standard methods / using Keys & Catalogues. Associated parasites and cercariometry in snails has been worked out by cercarial shedding. Human involvement at zo-onotic level has been performed in collaboration with Health centers and socio- economic aspect of inhabitants of study area.
Results
The snail diversity encountered 19 species including the vector species such as Indoplanorbis exustus, Gyraulus convexiusculus, Melanoides tuberculata and Lymnaea acuminata. The cercarial diversity comprised Furcocercous, Monostome, Amphistome and liver fluke / Xiphidiocercaria. During the study (2009–2010), 0.173% was found with cercarial dermatitis among human population in the selected area. The symptoms of disease recorded were red spots and swellings on effected parts of skin. Frequent visits of livestock to the water body and presence of vector snails provides a clue in completing the life cycle of the parasite of the family Schistosomatidae.
Conclusion
Cercarial dermatitis has been considered a potential risk at those places where warm blooded and snail’s hosts share a link with aquatic bodies with particular emphasis to temperature and time of year.
Keywords: Snail borne, Cercarial dermatitis, India
Introduction
Cercarial dermatitis is a parasitic disease with world-wide distribution, caused by the cercariae of animal schistosomes, if they enter in non-specific host for completion of life cycle. Though, the clinical cases of this disease have been reported from many countries in Europe and America, but scattered cases were recorded from southern end of South America (1). In India, the first report on dermatitis was from Mysore (Karnataka State) among the people who used waste tank for domestic purpose but the cercariae involved were not identified (2). It was experimentally demonstrated that only repeated exposures to cercariae could produce dermatitis in man (3–5). As per views of Hoeffler (6), cercarial dermatitis is a parasitic disease affecting the skin. A case of schisto-some cercarial dermatitis in man at Tiptur in Tumkur district in Karnataka (India) was observed in which both Indoplanorbis exustus and Lymnaea luteola snails were involved in the transmission of disease in a pond (7).
Basic ideas about endemic form of cercarial dermatitis (Khujlee) were emerged in Bastar area of Madhya Pradesh (India) where many villages had only one pond which fulfills all their needs (8, 9). Thus the same pond was used by villagers for bathing, washing, even drinking (except in few where hand pumps are used) and also for washing and bathing of their domestic animals-mainly cattle. An outbreak of cercarial dermatitis occurred in a recreational-tourist lake in the Quebec City region (Canada) in the summer (10). Besides this, the contributions of some parasitologists (11–14) can be cited who reported that the disease swimmer itch is caused by free-swimming larvae of bird parasites of the family Schistosomatidae (Trema-toda), which have penetrated through the skin.
Earlier in the Doon Valley, in northern India both the vector snails and pathogens have already been recorded (15–17) but there was no sign of occurrence of cercarial dermatitis. Henceforth, the present study is an attempt to provide a way forward towards malaco faunal diversity and distribution of snail borne parasitic diseases especially the cer-carial dermatitis in the chosen area.
Materials and Methods
Survey application on malaco-faunal diversity has been performed from the water bodies of the study areas [Sahaspur and Doiwala] in Doon Valley in district Dehradun in northern India having geographic co-ordinates of 30°18’ 56 N and 78 °2’ 0’ E at 652 msl. Snail sampling was done by applying standard methods (18) and the collected snails were identified using Keys and Catalogues (19, 20). Associated parasites and cercariometry in snails has been worked out by cercarial shedding (21–23). The sampling of the diseases cases was based on simple random technique. A questionnaire having questions in concerned with socio-economic aspects of inhabitants were interviewed and the data was procured.
Human involvement at zoonotic level has been worked out in the selected villages in collaboration with Health centers and socio-economic aspect of inhabitants of study area. Frequent visits to respective PHCs was made for procuring information on skin diseases and confirmation of present results. Simultaneously, a close look to frequently visiting livestock of the study area provided a clue of their potent role in completing the life cycle of the parasites.
Results
The snail diversity revealed the occurrence of 19 species belonging to 8 different families (Table 1). The collection sites from Sahaspur shared all the species while from Doiwala, the two species Seg-mentina calatha (Benson, 1850) and M. nevilli (Brot, 1874) were not reported.
Table 1:
Malaco-faunal diversity of the study area in Doon Valley (Uttarakhand), India during 2009 to 2010
| Sl.No. | Family | Molluscan species | Collection sites | |
|---|---|---|---|---|
| Sahaspur | Doiwala | |||
| 1 | Viviparidae | Bellamya bengalensis(Lamarck, 1822) | + | + |
| 2 | B. dissimilis(Mueller, 1774) | + | + | |
| 3 | B. crassa(Benson, 1836) | + | + | |
| 4 | Lymnaeidae | Lymnaea (Pseudosuccinea) acuminataf. hiansSowerby 1873 | + | + |
| 5 | L. luteola(Pseudosuccinea)f. ovalisGray, 1822 | + | + | |
| 6 | L. acuminata (Pseudosuccinea)f. patula(Troschel, 1837) | + | + | |
| 7 | Radix auricularia(Linnaeus, 1758) | + | + | |
| 8 | Pilidae | Pila globosa(Swainson 1822) | + | + |
| 9 | Buliinidae | Indoplanorbis exustus(Deshayes, 1834) | + | + |
| 10 | Planorbidae | Gyraulus convexiusculus(Hutton, 1849) | + | + |
| 11 | G. barrackporensis(Clessin, 1886) | + | + | |
| 12 | Planorbisplanorbis var. tangitarensisGermain 1918 | + | + | |
| 13 | Segmentina (Polypylis) calatha(Benson, 1850) | + | - | |
| 14 | Bithyniidae | Bithynia (Digoniostoma)pulchella(Benson, 1836) | + | + |
| 15 | Thiaridae | Melanoides tuberculata(Mueller 1774) | + | + |
| 16 | M. nevilli(Brot, 1874) | + | - | |
| 17 | Thiara (Thiara) scabra(Mueller, 1774) | + | + | |
| 18 | Brotia (Antimelania) costula(Rafinesque, 1833) | + | + | |
| 19 | Physidae | Physa acuta(Draparnaud, 1805) | + | + |
For cercariometry, the snails like I. exustus, M. tu-berculata, G. convexiusculus and L. acuminata were found infected with larval trematodes (Fig. 1a,b,c,d). The cercarial diversity comprised four different types viz., Furcocercous, Monostome, Amphistome and Liverfluke / Xiphidio cercariae. Among the collected snails, M. tuberculata have harbored with furcocercous, monostome and am-phistome cercariae whereas L. acuminata and I. ex-ustus released xiphidio and furcocercous cercariae. The infection was found more in winter than post monsoon, summer and monsoon seasons.
Fig. 1:
a) I. exustus b) M. tuberculata c) G. convexiusculus d) L. acuminata
A survey work on the spread of cercarial dermatitis has been made and some cases of dermatitis have been found. As many as, 24 villages under 7 blocks were surveyed for social status, occupation and skin infection among the inhabitants during January, 2009 to December, 2010. Among the persons examined, 0.173% was found with cercar-ial dermatitis (Table 2 and Fig. 2). Considering the cases of cercarial dermatitis and parasite infection found, the localities like Khushalpur, Dhali-pur, Jamanpur and Dudhlee in Doon Valley exhibited a positive correlation. But in the localities like Dhaki, Jhajhara, Lakhanwala, Rampur and Nahgal Bulandawala the pathogen was existed but no case of dermatitis was recorded. It has also been observed that in almost all the selected villages the farming was one of the occupations of the residing people. There were red spots and swellings on the effected parts of the skin. Frequent visits to respective PHCs was made for procuring information on skin disease and confirmation of present studies. It is noted that the physicians at PHC’s were in the doubtful position whether the skin infection is due to entrance of cercariae or due to allergic reaction of wild variety of grass (Parthenium hysterophorus).
Table 2:
Showing suspected cases of Cercarial dermatitis (C.D.) in selected areas of Doon valley
| Block/Area | Village | Persons Examined | Itching / Skin infection | Main Occupation | Cases of C.D. | ||||
|---|---|---|---|---|---|---|---|---|---|
| M | F | C | M | F | C | ||||
| Sahaspur | Dhaki | 87 | 38 | 70 | 27.7 | 13.1 | 52.8 | Business/Farming | |
| Redapur | 25 | 20 | 30 | 12 | 30 | 10 | Farming | ||
| Khushalpur | 64 | 46 | 118 | 50 | 15.2 | 37.2 | Business/Farming | 02 | |
| Charba | 45 | 25 | 41 | 6.6 | 20 | 34.1 | Business/Farming | ||
| Indripur | 30 | 31 | 43 | 26.6 | 19.3 | 20.9 | Farming | ||
| Prem Nagar | Terri Gaon | 29 | 29 | 33 | 27.5 | 31 | 12.1 | Business/Farming | |
| Teri Gaon | Kolu Pani | 27 | 17 | 30 | 18.5 | 17.6 | 13.3 | Business/Farming | |
| Suddhowala | Suddhowala | 12 | 10 | 18 | 8.3 | 10 | 22.2 | Business/Farming | |
| Jhajhara | 31 | 32 | 29 | 16.1 | 25 | - | Farming | ||
| Jassowala | 23 | 19 | 43 | 21.7 | 15.7 | 6.9 | Business/Farming | ||
| Herbertpur | Dhalipur | 19 | 17 | 29 | 15.7 | 25.5 | 13.7 | Business/Farming | 01 |
| Jamnipur | 32 | 32 | 40 | 15.6 | 34.3 | 15 | Business/Farming | ||
| Lakhanwala | 29 | 22 | 57 | 17.2 | - | 10.5 | Business/Farming | ||
| Bairagiwala | 24 | 25 | 39 | 25 | 12 | 7.6 | Business/Farming | ||
| Fatehpur | 23 | 15 | 13 | 13.0 | 6.6 | 23.0 | Business/Farming | ||
| Selaqui | Rampur | 52 | 32 | 67 | 17.3 | 21.8 | 10.4 | Farming | |
| Shonlearpur | 32 | 27 | 41 | 15.6 | 22.2 | 17.0 | Business/Farming | ||
| Muh. Nagar | 16 | 15 | 31 | 37.5 | 20 | 16.1 | Business/Farming | ||
| Jamanpur | 30 | 22 | 55 | 36.6 | 22.7 | 9.0 | Farming | 01 | |
| Chota Rampur | 22 | 16 | 48 | 18.1 | 18.7 | 8.3 | Business/Farming | ||
| Doiwala | Nangal Jwalapur | 20 | 19 | 28 | 5.0 | 15.7 | - | Business/Farming /Labour | |
| Simlash | 22 | 19 | 29 | - | 5.2 | 6.8 | Farming/Labour /Service | ||
| Dudhlee | 22 | 26 | 41 | 4.5 | 11.5 | 9.7 | Business/Farming /Labour | 02 | |
| Nahgal Bulanda-wala | 20 | 19 | 23 | 10.0 | 15.7 | - | Business/Farming /Labour | ||
Fig. 2:
Cases of cercarial dermatitis (Original)
Simultaneously, a close look to frequently visiting livestock of the study area provides a clue of their potent role in completing the life cycle of the parasites. In view of lack of information on skin infection, this needs a comprehensive study on the role of livestock/birds in the zoonotic transmission of the parasites.
Discussion
According to Hoeffler (6), the cercarial dermatitis is a parasitic disease affecting the skin. It may be encountered in fresh or salt water and is global in its distribution. It is a potential economic hazard to persons who work in aquatic environments and to the tourist industry. With regard to occurrence of cercarial dermatitis the present findings resemble with the contributions of a number of workers (7, 8, 24–28) but slightly differ in considering the role of species of snail. In our studies there is a major role of I. exustus and M. tuberculata.
Cercariae of several species of mammalian and avian schistosomes are responsible for causing dermatitis in man, during the act of skin penetration. These cercariae are unable to propagate and eventually perish. Known also as swimmer’s itch or paddy field dermatitis, it could be an occupational hazard for agricultural labourers, washer men and fishermen. This condition is rampant in rural India, where villagers are largely dependent on water ponds for their domestic and animal needs.
On a personal discussion with the village people there was a case of a young man who collected fresh water fish with bare hands from an irrigation pond. Minutes after collecting the fish, the person experienced itching and erythema on the dorsum of the hands. Soon, a few macules appeared on the hands and 6-7 h later these macules developed into papules. Routine anti-allergic treatment relieved the irritation and purities. But, later on appearance of cyst was noticed. This shows that the cercarial dermatitis exists in the Doon Valley.
Conclusion
Cercarial dermatitis should be considered a potential risk whenever warm-blooded and molluscan hosts share a water resource with man as it is a self-limited, severely itching rash that lasts about one week and may be easily mistaken for insect bites. More emphasis has been given on (a) the temporal occurrence of cercarial dermatitis in humans and (ii) the prevalence of animal schisto-some infection in vector snails and the level of cercarial shedding in relation to time of year and water temperature.
Ethical considerations
Ethical issues (Including plagiarism, Informed Consent, misconduct, data fabrication and/or falsification, double publication and/or submission, redundancy, etc.) have been completely observed by the authors.
Acknowledgements
We are grateful to the authorities of Uttarakhand State Council of Science & Technology for financial assistance and to Dr. P.T. Bhutia, Ex-Additional Director, Zoological Survey of India, Deh-radun for useful suggestions. The authors declare that there is no conflict of interests.
References
- Cort WW (1950). Studies on schistosome dermatitis XI. Status of knowledge after more than twenty years. Amer J Hygn, 52: 251–307. [PubMed] [Google Scholar]
- Bhalerao GD (1948). Blood fluke problem in India. Proceedings of 35th Indian Science Congress part II: 57–71. [Google Scholar]
- Oliver L (1949). Schistosome dermatitis – a sensitization phenomenon. Amer J Hygn, 49: 290–302. [DOI] [PubMed] [Google Scholar]
- Anantraman M (1958). On schistosome dermatitis: I Dermatitis in India caused by cercariae of Schistosomaspindale Montogomery, 1906. Indian J Helminthology, 10(1): 46–52. [Google Scholar]
- Anandan R (1985). Studies on Schistosomanasale, Rao, 1933 (Trematoda, Schistosomatidae), Ph. D. Thesis, Tamil Nadu Agricultural University, Coimbatore. [Google Scholar]
- Hoeffler DF (1977). “Swimmers itch” (cercarial dermatitis). Cutis, 19(4): 461–465,467. [PubMed] [Google Scholar]
- Muraleedharan K, Prasanna Kumar S and Hegde KS (1977). Larval trematodes infections in aquatic snails in Karnataka-a preliminary study. Mysore J Agricultural Sci, 11: 101–104. [Google Scholar]
- Agrawal MC, Gupta S and George J (2000. a). Cercarial dermatitis in India. Bull WHO, 78(2): 1–2. [PMC free article] [PubMed] [Google Scholar]
- Agrawal MC, Pandey S, Sirmour S and Deshmukh PS (2000. b). Endemic form of cercarial dermatitis (Khujlee) in Bastar area of Madhya Pradesh. J Parasitic Dis, 24(2): 217–218. [Google Scholar]
- Levesque B, Giovenazzo P, Guerrier P, Laverdiere D and Prud’Homme H. (2002). Investigation of an outbreak of cercarial dermatitis. Epidemiol Infect, 129(2): 379–386. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gaitonde BB, Sathe BD, Mukerji S, Sutar NK, Athalye RP, Kotwal VP and Renapurkar DM. (1981). Studies of schistosomiasis in village Gimvi of Maharashtra. India J Med Res, 74: 352–357. [PubMed] [Google Scholar]
- Skirnisson K and Kolarova L (2005). Swimmer’s itch in Landmannalaugar, Iceland. Laeknabladid, 91(10): 729–736. [PubMed] [Google Scholar]
- Valdovinos C and Balboa C (2008). Cercarial dermatitis and lake eutrophication in south-central Chile. Epidemiol Infect, 136: 391–394. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Skirnisson K, Aldhoun JA and Kolarova L (2009). A review on swimmer’s itch and the occurrence of bird schistosome in Iceland. J Helminthol, 83(2): 165–171. [DOI] [PubMed] [Google Scholar]
- Pokhriyal BP Jauhari RK and Sudarshana R (1998). Trematode cercariae infection in the snail, Thiara (Melanoides) tuberculata (Mueller, 1774) in different localities of Doon-Valley, India. J Exp Zool India, 1(2): 107–110. [Google Scholar]
- Pokhriyal BP, Mahesh RK and Jauhari RK (1997). Prevalence of trematodecercarial infection in the snail Lymnaea (Pseudosuccinea) acuminata Lamarck, 1822 in different localities of Dehradun Valley. Bioved, 8 (1, 2): 15–19. [Google Scholar]
- Pokhriyal BP, Mahesh RK and Jauhari RK (1998. a). Studies on the molluscan diversity of Asan river system in Doon Valley with special reference to vectors of trematode parasites. Indian J Forestry, 21(2): 167–170. [Google Scholar]
- Ouma JH, Sturrock RF, Klumpp RK and Kariuki HC (1989). A comparative evaluation of snail sampling and cercariometry to detect Schistosomamansoni transmission in a large-scale, longitudinal field study in Machakos, Kenya. Parasitology, 99: 349–355. [DOI] [PubMed] [Google Scholar]
- Subbarao NV (1989). Fresh water molluscs of India. Handbook Zoological Survey of India, Calcutta: XXIII + 1–289. [Google Scholar]
- Ramakrishna and Dey A (2007). Handbook on Indian freshwater molluscs. Zoological Survey of India, Kolkata, P. 1–399. [Google Scholar]
- Yamaguti S (1975). A synoptical review of life histories of digenetic trematodes of vertebrates. Keiguku Publication Co. Tokyo, Japan: Pp. 590. [Google Scholar]
- Cheng TC (1986). The Biology of Animal Parasites, W.B. Saunders Company, Philadelphia and London: 243–248 pp. [Google Scholar]
- Kariuki HC, Clennon JA, Brady MS, Kitron U, Sturrock RF, Ouma JH, Ndzovu ST, Mungai P, Hoffman O, Hamburger J, Pellegrini C, Muchiri EM and King CH (2004). Distribution patterns and cercarial shedding of Bulinusnasutus and other snails in the Msambweni area, Coast Province, Kenya. Amer J Trop Med Hygn, 70(4): 449–456. [PubMed] [Google Scholar]
- Schwabe CW (1984). Veterinary medicine and human health, 3rd edn., Williams and Wilkins, Baltimore, pp. 472–485. [Google Scholar]
- Narain K, Mahanta J, Dutta R and Dutta P (1994): Paddy field dermatitis in Assam: a Cercarial Dermatitis. J Commun Dis, 26(1): 26–30. [PubMed] [Google Scholar]
- Narain K, Rajguru SK and Mahanta J (1998). Incrimination of Schistosomaspindale as a causative agent of farmer’s dermatitis in Assam with a note on liver pathology in mice. J Commun Dis, 30(1): 1–6. [PubMed] [Google Scholar]
- Chhabra MB and Pathak KML (2008). Helmithzoonoses in India: a resurgent problem. J Parasitic Dis, 32(7): 77–86. [Google Scholar]
- Bin Kabir H, Eliyas M, Hashem A, Mohiuddin and Miazi OF (2010). Prevalence of zoonotic parasitc diseases of domestic animals in different abattoir of Comilla and Brahman Baria region in Bangladesh. Univ J Zool Rajshahi Univ, 28: 21–25. [Google Scholar]