Maria Tereza Pepe Razzolini

Impactos na saúde das deficiências de acesso a água

O acesso regular a agua potavel e segura tem causado preocupacao, principalmente em paises em desenvolvimento e, mais enfaticamente em areas periurbanas, que abrigam a populacao socialmente excluida. O objetivo deste trabalho e abordar questoes de acesso a agua em regioes periurbanas e para tanto foi realizado levantamento bibliografico nas bases de dados Pubmed, Medline e SciELO assim como relatorios da OMS, OPAS, IBGE e Ministerio das Cidades. A falta ou a precariedade do acesso a agua representa situacao de risco que propicia aumento da incidencia de doencas infecciosas agudas e da prevalencia de doencas cronicas. O estabelecimento do grau de acesso a agua de qualidade considera fatores como distância e tempo percorrido ate a fonte de agua, volume coletado, demanda atendida e nivel de prioridade de acoes de intervencao. Na qualidade da agua, consideram-se como fatores de impacto o manuseio - maneira como ocorre a coleta, o transporte, o armazenamento e o uso -, a presenca de patogenos nas fontes e as praticas rotineiras da populacao. A determinacao da presenca de patogenos nas fontes evidencia o risco a saude e a identificacao do agente etiologico indica a origem da contaminacao. O caminho para reverter esse cenario e a implementacao integrada de politicas publicas de gestao, que envolvam acoes conjuntas e ajustadas nos setores de desenvolvimento urbano, habitacao, saneamento e saude e que visem a promocao e a protecao da saude da populacao local e ao enfrentamento da complexidade de fatores que evidenciam sua vulnerabilidade.

Assessing the infection risk of Giardia and Cryptosporidium in public drinking water delivered by surface water systems in Sao Paulo State, Brazil.

A survey of Giardia and Cryptosporidium was conducted in surface water used as drinking water sources by public water systems in four densely urbanized regions of Sao Paulo State, Brazil. A Quantitative Microbial Risk Assessment, based on protozoa concentrations, was performed to estimate the probability of protozoa infection associated with drinking water ingestion. A total of 206 source water samples were analyzed over a 24 month period using the USEPA Method 1623. The risk of infection was estimated using an exponential dose response model, children and adults exposure and a gamma distribution for (oo)cyst concentrations with three scenarios for treating censored data. Giardia was detected in 102 of the samples, and 19 of them were also positive for Cryptosporidium, with maximum concentrations of 97.0 cysts/L and 6.0 oocysts/L, respectively. Risk distributions were similar for the three scenarios. In the four regions, the estimated risk of Giardia infection per year, for adults and children, ranged from 0.29% to 2.47% and from 0.08% to 0.70%, respectively. Cryptosporidium risk infection varied from 0.15% to 0.29% for adults and from 0.04% to 0.08% for children. In both cases, the calculated risk surpassed the risk of infection of 10(-4) (1:10,000) defined as tolerable by USEPA for a yearly exposure. The probability of Giardia infection was very close to the rates of acute diarrheic disease for adults (1% to 3%) but lower for children (2% to 7%). The daily consumption of drinking water was an important contributing factor for these differences. The Microbiological Risk Assessment carried out in this study provides an indication of infection risks by Giardia and Cryptosporidium in the population served by these source waters. Strategies for source water protection and performance targets for the water treatment should be established to achieve the required level of public health risk.

Environmental conditions and rodent infestation in Campo Limpo district, São Paulo municipality, Brazil

Rodents are involved in the transmission to human beings of several diseases, including liptospirosis, which shows high lethality rates in São Paulo municipality. Despite this, few studies have assessed the relationship existing between urban environmental conditions and building rodent infestation. With the purpose of clarifying this relationship, an analysis has been conducted in order to quantify the influence of environmental factors upon rodent infestation on a low-income district. Diagnosis of the environmental situation has been performed to evaluate the frequency according to which harborage, food and access sources occur, and a survey on infestation rates in 2175 dwellings in the area studied. The logistic regression analysis showed that among the environmental variables, the one that showed the closest association with rodent infestation was access; followed by harborage, and food. It was concluded that poor socioeconomic and environmental conditions in the area propitiate the occurrence of high rodent infestation rates.

Risk of Giardia infection for drinking water and bathing in a peri-urban area in Sao Paulo, Brazil.

A high incidence of waterborne diseases is observed worldwide and in order to address contamination problems prior to an outbreak, quantitative microbial risk assessment is a useful tool for estimating the risk of infection. The objective of this paper was to assess the probability of Giardia infection from consuming water from shallow wells in a peri-urban area. Giardia has been described as an important waterborne pathogen and reported in several water sources, including ground waters. Sixteen water samples were collected and examined according to the US EPA (1623, 2005). A Monte Carlo method was used to address the potential risk as described by the exponential dose response model. Giardia cysts occurred in 62.5% of the samples (<0.1–36.1 cysts/l). A median risk of 10−1 for the population was estimated and the adult ingestion was the highest risk driver. This study illustrates the vulnerability of shallow well water supply systems in peri-urban areas.

Quantification and characterization of Salmonella spp. isolates in sewage sludge with potential usage in agriculture

BackgroundThis study aims to scrutinize Salmonella spp. and its serotypes in sewage sludge samples from wastewater treatment plants, and assesses the presence of virulence genes and antibiotics resistant to the profile. Samples (n = 54) were collected and analyzed in accordance with the EPA Method 1682/2006. For positive serological reaction, 40 strains were selected for PCR analyses and detection of spvC, invA and sseL virulence genes, plasmid presence and resistance to antibiotics.ResultsSalmonella spp. was detected in 38.9% of the samples collected (<0.006473 to 12.19 MPN/gTS). The most prevalent serotype was Salmonella Infantis. All Salmonella spp. (n = 35) presented at least one of the three virulence genes mentioned above and 40% harboured plasmids. Salmonella Typhimurium strains were isolated harbouring at least one of the following virulence genes: spvC, invA or sseL. Four Salmonella spp. isolates were resistant to tetracycline; three were resistant to trimethoprim-sulfamethoxazole, and one isolate was resistant to ciprofloxacin. Two Salmonella spp. strains presented multi resistance to antimicrobial agents.ConclusionsThe results obtained demonstrated that Salmonella spp. have been found in sewage sludge, thus it is essential to set measures to mitigate human health risks when it is intended to be applied on agricultural soils.

Evolução do acesso à água fluoretada no Estado de São Paulo, Brasil: dos anos 1950 à primeira década do século XXI

Ter acesso a agua fluoretada e um reconhecido fator de protecao contra a carie dentaria. No Brasil, a fluoretacao da agua de abastecimento publico tornou-se obrigatoria por lei em 1974, seguindo-se a esta regulamentacao acentuada expansao da cobertura, sobretudo nas regioes de maior desenvolvimento socioeconomico. A ampliacao dessa cobertura em todo o pais e uma das prioridades da politica nacional de saude bucal. Neste artigo, sistematizam-se informacoes sobre a implantacao e expansao da fluoretacao no Estado de Sao Paulo, no periodo de 1956 a 2009, utilizando-se dados secundarios obtidos em relatorios tecnicos, documentos oficiais e no sistema SISAGUA. Em 2009, a cobertura se estendia por 546 (84,7%) dos 645 municipios paulistas, chegando a 85,1% da populacao total e a 93,5% da populacao com acesso a rede de distribuicao de agua. Tais resultados indicam que a medida esta consolidada como parte da politica estadual de saude. No entanto, persiste o desafio de implantar e manter a fluoretacao em 99 municipios, beneficiando cerca de 6,2 milhoes de habitantes excluidos do beneficio.Access to fluoridated water is a known protective factor against dental caries. In 1974, fluoridation of the public water supply became mandatory by law in Brazil, resulting in improved coverage, especially in more developed regions of the country. Coverage increased across the country as a priority under the national oral health policy. This article systematizes information on the implementation and expansion of fluoridation in Sao Paulo State from 1956 to 2009, using secondary data from technical reports, official documents, and the Information System for Surveillance of Water Quality for Human Consumption (SISAGUA). In 2009, fluoridation covered 546 of 645 counties in São Paulo State (84.7%), reaching 85.1% of the total population and 93.5% of the population with access to the public water supply. The results indicate that fluoridation has been consolidated as part of State health policy. However, the challenge remains to implement and maintain fluoridation in 99 counties, benefiting 6.2 million inhabitants that are still excluded from this service.

Water reclamation redesign for reducing Cryptosporidium risks at a recreational spray park using stochastic models.

Recreational outbreaks associated with sprayparks are well recognized, and may be partly due to the engineering designs used for their water reclamation systems are problematic to control. This work is based on an outbreak of cryptosporidiosis linked to a spraypark in New York State, where it was determined, specifically that the spraypad (the main attraction) was the primary exposure point. We first determined the likely dose the spraypad users were exposed to, then modeled the efficacy of the treatment system and used this to inform a Monte Carlo method to estimate the probability of infection and illness for the users of the spraypad. The current treatment system which consists of; two holding tanks, a dual media filter and chlorine injection as well as two design change recommendations were modeled using three independent Markov chain models. Within the current treatment system design the receiving tank for the treatment train is also connected with a second pipe to the spraypad used to deliver the return (treated) water, this return pipe is acting potentially as a bypass for the treatment train. Based on the risk assessments performed it is recommended that the bypass pipe be removed from the treatment system since in doing so the probability of infection and illness were reduced appreciably. Secondarily including an ozone contactor was shown to slightly reduce the risk further and provide a multiple barrier.

Microbiological quality assessment of sand and water from three selected beaches of South Coast, São Paulo State, Brazil

This study aimed to assess the sanitary quality of water, and wet and dry sand from three beaches located in the South Coast region of São Paulo State, Brazil, selected taking into account the frequency of tourists and the water quality (good, fair and poor). Thirty-six water samples each of wet and dry sand and seawater were collected monthly over a period of one year and analyzed for fecal indicator bacteria (FIB: thermotolerant coliforms, Escherichia coli, and enterococci), presumptive Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans and dermatophytes. The results revealed FIB concentrations more elevated in dry sand followed by wet sand and water. P. aeruginosa and presumptive S. aureus were detected with a similar frequency in water and sand samples, but maximum concentrations and geometric means were higher in dry sand. C. albicans was detected only in water samples whereas the dermatophyte Microsporum sp. was isolated exclusively from dry and wet sand samples. This evaluation showed also that the environment had a significant influence on P. aeruginosa but not on presumptive S. aureus concentrations. According to threshold values proposed in the literature for E. coli and enterococci dry sand densities, none of the beaches would be considered of sufficient quality for recreational activities.

Quality of water sources used as drinking water in a Brazilian peri-urban area

The objective of this paper was to assess bacteriological quality of drinking water in a peri-urban area located in the Metropolitan Region of Sao Paulo, Brazil. A total of 89 water samples were collected from community plastic tanks and 177 water samples from wells were collected bimonthly, from September 2007 to November 2008, for evaluating bacteriological parameters including: Escherichia coli, Enterococcus and heterotrophic plate count (HPC). Clostridium perfringens was investigated in a subsample (40 samples from community plastic tank and 40 from wells). E. coli was present in 5 (5.6%) samples from community plastic tanks (2.0 - 5.1x104 MPN/100mL) and in 70 (39.5%) well samples (2.0 - 8.6x104 MPN/100mL). Thus, these samples were not in accordance with the Brazilian Regulation. Enterococcus was detected in 20 (22.5%) samples of the community plastic tanks (1 to 79 NC/100mL) and in 142 (80.2%) well samples (1 to >200 NC/100mL). C. perfringens was detected in 5 (12.5%) community plastic tanks samples and in 35 (87.5%) wells samples (2.2 to >16 MPN/100mL). HPC were above 500 CFU/mL in 5 (5.6%) waters from community plastic tanks. In wells samples, the HPC ranged from <1 to 1.6x104 CFU/mL. The residual chlorine did not attend the standard established in the drinking water legislation (0.2 mg/L), except in 20 (22.5%) samples. These results confirm the vulnerability of the water supply systems in this peri-urban area what is clearly a public health concern.

Aeromonas presence in drinking water from collective reservoirs and wells in peri-urban area in Brazil

Aeromonas genus is considered an emerging pathogen and its presence in drinking water supplies is a reason to public health concern. This study investigated the occurrence of Aeromonas in samples from collective reservoirs and wells used as drinking water sources in a peri-urban area. A total of 35 water samples were collected from collective reservoirs and 32 from wells bimonthly, from September 2007 to September 2008. Aeromonas spp determination was carried out using a Multiple-Tube Technique. Samples were inoculated into alkaline peptone water and the superficial film formed was transferred to blood agar plates amended with ampicillin. Typical Aeromonas colonies were submitted to a biochemical screening and then to biochemical tests for species differentiation. Aeromonas was detected in 13 (19%) of the 69 samples examined (6 from collective reservoirs and 7 from wells). Concentrations of Aeromonas in collective reservoirs ranged from <0.3 to 1.2 x102MPN/100mL and, in wells, from <0.3 to 2.4 x102MPN/100mL. The most frequent specie in the collective reservoir samples was Aeromonas spp (68%), followed by A. encheleia (14%) and A. allosaccharophila (8%) and A. hydrophila (8%). Aeromonas spp (87%) was the most frequent specie isolated from well samples, followed by A. allosacchariphila (8%), A. encheleia (2%) and A. jandaei (5%). These data show the presence and diversity of Aeromonas genus in the samples analyzed and highlight that its presence in drinking water poses a significant public health concern.