Seasonal contamination of public squares and lawns by parasites with zoonotic potential in southern Brazil

Abstract

The presence of helminths and protozoans in public squares and lawns of the city of Maringá, southern Brazil, during winter and summer was assessed in order to evaluate their seasonal fluctuations in relation to edaphic and climatic factors. Samples were collected from January 2003 through June 2004 in 90% (13) of all public squares covered by sand, and in 30% (4) of all lawns used as leisure areas. The samples were analysed quantitatively by modified centrifugal-flotation and sedimentation in water techniques, and qualitatively by a method based on positive larval thermo-hydrotropism. Meteorological data were recorded, and physical, chemical and structural characteristics of the soil were analysed. One hundred and thirty samples of sand from squares, 65 in summer and 65 in winter, and 40 samples of grass from lawns, 20 in each season, were collected. All samples from lawns, 62 (95.38%) from squares in winter and 45 (69.23%) in summer, contained protozoans and/or helminths. Eggs of Toxocara spp. were the most frequently observed parasites in both winter and summer in squares (P < 0.0001) and in lawns (P = 0.6142), being equally distributed among the different locations (P = 0.2038). Species diversity was lower in winter; fewer parasites were found in summer. This region, with a tropical climate and a mild winter dry season, has favourable edaphic and climatic conditions for soil contaminants to persist year-round. In addition, the high frequency of animals such as dogs and cats and the poor sanitary measures in force made it possible for zoonoses to be transmitted in the public spaces.

Contamination of public parks in Presidente Prudente (São Paulo, Brazil) by Toxocara spp. eggs

“…Seasonal fluctuation may also influence the recovery of eggs from soil samples (CHIEFFI; MÜLLER, 1976;QUEIROZ et al, 2006). Nevertheless, in southern Brazil, there are no difference between the numbers of eggs recovered in summer and winter (TIYO et al, 2008). In the present study, eggs were detected throughout the year, but the recovery rate was significantly higher in autumn, in contrast with some studies carried out in south Brazil.…”

Serological, clinical and epidemiological evaluation of toxocariasis in urban areas of south Brazil

“…In the city of Maringá, in the state of Paraná, south Brazil, seropositivity in children attended at the Municipal Hospital was 28.8% 23 and eggs of Toxocara spp. were the most frequently observed parasitic structure distributed among the different locations 33 . These results stimulated the authors to carry out an epidemiological survey in others municipalities of the same region.…”

“…Parasite contamination of soil in recreation areas has been investigated in different parts of the world 6,15,21,33 with different positivity rates.…”

Microbiological quality of drinking rainwater in the inland region of Pajeú, Pernambuco, Northeast Brazil

“…Higher bacterial densities are observed during the rainy season than during the dry season 16 , thus further studies are required to monitor seasonal variation of bacterial and parasite quality of ready-to-drink water of Tuparetama.…”