Microbiological Evaluation of 5 L- and 20 L-Transparent Polypropylene Buckets for Solar Water Disinfection (SODIS).

BACKGROUND: Solar water disinfection (SODIS) is an appropriate technology for household treatment of drinking water in low-to-middle-income communities, as it is effective, low cost and easy to use. Nevertheless, uptake is low due partially to the burden of using small volume polyethylene terephthalate bottles (1.5-2 L). A major challenge is to develop a low-cost transparent container for disinfecting larger volumes of water. (2) Methods: This study examines the capability of transparent polypropylene (PP) buckets of 5 L- and 20 L- volume as SODIS containers using three waterborne pathogen indicators: Escherichia coli, MS2-phage and Cryptosporidium parvum. (3) Results: Similar inactivation kinetics were observed under natural sunlight for the inactivation of all three organisms in well water using 5 L- and 20 L-buckets compared to 1.5 L-polyethylene-terephthalate (PET) bottles. The PP materials were exposed to natural and accelerated solar ageing (ISO-16474). UV transmission of the 20 L-buckets remained stable and with physical integrity even after the longest ageing periods (9 months or 900 h of natural or artificial solar UV exposure, respectively). The 5 L-buckets were physically degraded and lost significant UV-transmission, due to the thinner wall compared to the 20 L-bucket. (4) Conclusion: This work demonstrates that the 20 L SODIS bucket technology produces excellent bacterial, viral and protozoan inactivation and is obtained using a simple transparent polypropylene bucket fabricated locally at very low cost ($2.90 USD per unit). The increased bucket volume of 20 L allows for a ten-fold increase in treatment batch volume and can thus more easily provide for the drinking water requirements of most households. The use of buckets in households across low to middle income countries is an already accepted practice.

Occurrence of Giardia and Cryptosporidium in wild birds in Galicia (Northwest Spain).

Faecal samples were obtained from 433 wild birds being treated in wildlife recovery centres in Galicia (Northwest Spain), between February 2007 and September 2009. The birds belonged to 64 species representing 17 different orders. Giardia cysts and Cryptosporidium oocysts were detected by an immunofluorescence antibody test and identified at the molecular level by established PCR-sequencing methods. The overall prevalence of Giardia was 2·1% and that of Cryptosporidium, 8·3%. To our knowledge, this is the first description of Giardia sp. in Tyto alba and Caprimulgus europaeus; and of Cryptosporidium sp. in Apus apus, Athene noctua, C. europaeus, Falco tinnunculus, Morus bassanus, Parabuteo unicinctus and Strix aluco. Furthermore, the first PCR-sequence confirmed detection of Giardia duodenalis assemblage B in, Buteo buteo, Coturnix coturnix and Pica pica; G. duodenalis assemblage D in Garrulus glandarius; and G. duodenalis assemblage F in Anas platyrhynchos; Cryptosporidium parvum in Accipiter nisus, B. buteo, Milvus migrans, Pernis apivorus and P. pica; and Cryptosporidium meleagridis in Streptopelia turtur. The study findings demonstrate the wide spread of Giardia and Cryptosporidium between wild birds.

Giardia and Cryptosporidium in cetaceans on the European Atlantic coast.

The occurrence of Giardia and Cryptosporidium was investigated in cetacean specimens stranded on the northwestern coast of Spain (European Atlantic coast) by analysis of 65 samples of large intestine from eight species. The parasites were identified by direct immunofluorescence antibody test (IFAT) and by PCR amplification of the ß-giardin gene, the ITS1-5.8S-ITS2 region and the SSU-rDNA gene of Giardia and the SSU-rDNA gene of Cryptosporidium. Giardia and Cryptosporidium were detected in 7 (10.8 %) and 9 samples (13.8 %), respectively. In two samples, co-infection with both parasites was observed. Giardia duodenalis assemblages A, C, D and F, and Cryptosporidium parvum were identified. This is the first report of G. duodenalis in Balaenoptera acutorostrata, Kogia breviceps and Stenella coeruleoalba and also the first report of Cryptosporidium sp. in B. acutorostrata and of C. parvum in S. coeruleoalba and Tursiops truncatus. These results extend the known host range of these waterborne enteroparasites.

Benthic macroinvertebrate communities as aquatic bioindicators of contamination by Giardia and Cryptosporidium.

Benthic macroinvertebrates (community composed mostly by aquatic forms of insects, such as stonefly nymphs, dragonfly nymphs, water bugs or beetle larvae) are often used in biological monitoring programmes to evaluate the ecological status of rivers and thus to indicate the repercussions of anthropogenic activities. The aim of the present study was to evaluate the use of this indicator community to detect human enteroprotozoan parasites that are transmitted via water. In total, 32 samples of macroinvertebrates were collected, with the aid of surber nets of mesh size 500 µm, from nine rivers in Galicia (NW Spain), on different occasions between 2005 and 2009. The samples were homogenised (0.04 M phosphate buffered saline, pH 7.2), sieved (150 and 45 µm mesh), and concentrated (by a diphasic method). Aliquots of the sediments were then analysed by a direct immunofluorescence technique with monoclonal antibodies against Giardia and Cryptosporidium. Giardia cysts were detected in one (3.1%) of the samples and Cryptosporidium oocysts were detected in four (12.5%) of the samples. This work is the first study carried out to investigate the presence of Giardia and Cryptosporidium in this benthic community. The results demonstrate that benthic invertebrates could be used as bioindicators of contamination by these waterborne protozoans. Moreover, as this aquatic organisms act as intermittent accumulators and its monitoring enables chronological analysis of perturbations, in both the short- and mid-term, this may represent a suitable alternative or complementary method to the usual techniques of detecting human and animal enteropathogens in water samples.

Detection of zoonotic and livestock-specific assemblages of Giardia duodenalis in free-living wild lizards.

Giardia duodenalis is a zoonotic parasite that infects the gut of a wide range of vertebrates, including numerous wildlife species. However, little is known about this protozoan parasite in reptiles. Fecal samples from 31 wild lizards were collected in Galicia (northwest Spain) and screened for the presence of Giardia by PCR amplification and sequencing of the ITS1-5.8S-ITS2 region in the ribosomal unit. This allowed detection of the parasite in 5 samples (16.1%), and enabled identification of G. duodenalis assemblage A2 in two samples of Iberian rock lizard (Iberolacerta monticola), G. duodenalis assemblage B in other two samples of I. monticola, and G. duodenalis assemblage E in one sample of Bocage's wall lizard (Podarcis bocagei). The results obtained after PCR amplification and sequencing of the SSU-rDNA gene confirmed the presence of G. duodenalis assemblage A in two samples of I. monticola. This is the first report of G. duodenalis in free-living lizards, although further studies are needed to distinguish between actual infection and mechanical dissemination of cysts. The detection of zoonotic and livestock-specific assemblages of G. duodenalis demonstrates the wide environmental contamination by this parasite, possibly due to human activities.

Detection of zoonotic and livestock-specific assemblages of Giardia duodenalis in free-living wild lizards / Detecção de genótipos de Giardia duodenalis zoonóticos e específicos de ruminantes domésticos em lagartos selvagens

Abstract Giardia duodenalis is a zoonotic parasite that infects the gut of a wide range of vertebrates, including numerous wildlife species. However, little is known about this protozoan parasite in reptiles. Fecal samples from 31 wild lizards were collected in Galicia (northwest Spain) and screened for the presence of Giardia by PCR amplification and sequencing of the ITS1-5.8S-ITS2 region in the ribosomal unit. This allowed detection of the parasite in 5 samples (16.1%), and enabled identification of G. duodenalis assemblage A2 in two samples of Iberian rock lizard (Iberolacerta monticola), G. duodenalis assemblage B in other two samples of I. monticola, and G. duodenalis assemblage E in one sample of Bocage's wall lizard (Podarcis bocagei). The results obtained after PCR amplification and sequencing of the SSU-rDNA gene confirmed the presence of G. duodenalis assemblage A in two samples of I. monticola. This is the first report of G. duodenalis in free-living lizards, although further studies are needed to distinguish between actual infection and mechanical dissemination of cysts. The detection of zoonotic and livestock-specific assemblages of G. duodenalis demonstrates the wide environmental contamination by this parasite, possibly due to human activities.

Resumo Giardia duodenalis é um parasito zoonótico que infecta o intestino delgado de uma ampla gama de vertebrados, sendo detectado em numerosas espécies selvagens. No entanto, pouco se conhece sobre a presença deste parasito protozoário em répteis. Para estudar a presença de Giardia, foram obtidas amostras fecais provenientes de 31 lagartos e coletadas em diferentes localizações de Galicia (Noroeste da Espanha). Mediante a aplicação da técnica de PCR e posterior sequenciamento da região ITS1-5.8S-ITS2 da unidade ribossômica, detectou-se Giardia em 5 amostras (16,1%), identificando-se o genótipo A2 de G. duodenalis em 2 amostras de lagartos da montanha (Iberolacerta monticola), G. duodenalis genótipo B em outras 2 amostras de I. monticola e G. duodenalis genótipo E em outra amostra de lagarto de Bocage (Podarcis bocagei). Os resultados obtidos, após amplificação e sequenciamento de um fragmento do gene SSU-rDNA, confirmam a presença de G. duodenalis genótipo A em 2 amostras de I. monticola. Esta é a primeira vez que se descreve G. duodenalis em lagartos selvagens, embora sejam necessários outros estudos complementares para confirmar se estes animais sofrem uma infecção real ou se apenas atuam como disseminadores mecânicos da contaminação ambiental. Além disso, a detecção de genótipos zoonóticos e específicos de ruminantes domésticos demonstra a contaminação do ambiente selvagem por G. duodenalis, possivelmente devido à atividade humana.