Entomological investigation of a sylvatic yellow fever area in São Paulo State, Brazil

Following reports of two autochthonous cases of sylvatic yellow fever in the State of S?o Paulo, Brazil, in 2000, entomological surveys were conducted with the objective of verifying the occurrence of vector species in forest environments close to or associated with riparian areas located in the western and northwestern regions of the State. Culicidae were captured in 39 sites distributed in four regions. Haemagogus leucocelaenus and Aedes albopictus were the most abundant species and were captured in all the regions studied. H. leucocelaenus was the most abundant species in the municipalities of Santa Albertina and Ouroeste, where the two cases of sylvatic yellow fever had been reported. Mosquitoes from the janthinomys/capricornii group were only found at eight sites in the S?o José do Rio Preto region, while Sabethes chloropterus was found at one site in Ribeir?o Preto. H. leucocelaenus showed its capacity to adapt to a secondary and degraded environment. Our results indicate a wide receptive area for yellow fever transmission in the State of S?o Paulo, with particular emphasis on the possibility of H. leucocelaenus being involved in the maintenance of this sylvatic focus of the disease.     

Spotted fever in Campinas region,State of São Paulo,Brazil

Brazilian spotted fever was detected for the first time in the State of S o Paulo in 1929. However, there is no systematic reporting of the disease in the State. In 1985, three cases of the disease occurred in the municipality of Pedreira, located in the Campinas Region, belonging to the 5th Administrative Region, in the Northeast part of the State, including 88 municipalities. An investigation was conducted at the time, but the lack of case registry limited its scope. The present study was undertaken with the aim of recovering the history of the disease in the Region. Data recovered from several public health services for 1985-2000 were used to analyze incidence patterns. It was observed that the transmission area expanded and the number of suspected cases increased, especially after 1996, when mandatory reporting was established. Deaths due to spotted fever were observed in most of the years under study. The study concluded that spotted fever incidence is increasing in the Campinas Region. Complementary bio-ecological studies are currently under way to better understand the epidemiology of this disease, recognized worldwide as an emerging public health problem.     

Isolation of Histoplasma capsulatum from bats in the urban area of São Paulo State, Brazil

The presence of bats in caves, attics, ceilings, and roofs is important epidemiologically as they can increase the chance of human acquisition of pathogens, including Histoplasma capsulatum. Brazilian urban areas contain many species of bats, especially insectivorous bats, that are attracted by a wide range of readily available food and shelter. From August 2003 to December 2008, we analysed 2427 bats in the S?o Paulo State region. Homogenates of the livers and spleens of the bats were plated on specific medium to identify animals infected with H. capsulatum. The fungus was isolated from 87 bats (3·6%). The infected bats were identified as Molossus molossus (74), Nyctinomops macrotis (10), Tadarida brasiliensis (1), Molossus rufus (1) and Eumops glaucinus (1), all insectivorous species. The data presented are a relevant contribution to the epidemiology of H. capsulatum in densely populated urban areas such as in S?o Paulo State, especially since histoplasmosis is not included in the mandatory disease notification system.     

Dengue and the risk of urban yellow fever reintroduction in São Paulo State,Brazil

OBJECTIVE: To propose a mathematical method for the estimation of the Basic Reproduction Number, R0, of urban yellow fever in a dengue-infested area. METHODS: The method is based on the assumption that, as the same vector (Aedes aegypti) causes both infections, all the quantities related to the mosquito, estimated from the initial phase of dengue epidemic, could be applied to yellow fever dynamics. It is demonstrated that R0 for yellow fever is, on average, 43% lower than that for dengue. This difference is due to the longer dengue viremia and its shorter extrinsic incubation period. RESULTS: In this study the analysis was expanded to the epidemiological situation of dengue in S o Paulo in the year 2001. The total number of dengue cases increased from 3,582 in 2000 to 51,348 in 2001. It was then calculated R0 for yellow fever for every city which have shown R0 of dengue greater than 1. It was also estimated the total number of unprotected people living in highly risky areas for urban yellow fever. CONCLUSIONS: Currently there is a great number of non-vaccinated people living in Aedes aegypti infested area in the state of S?o Paulo.     

Prevalence of Cryptosporidium sp. in institutionalized dogs in the city of São Paulo, Brazil

OBJECTIVE: Dogs play an important role as infection source of human cryptosporidiosis. The objective of the study was to determine the prevalence of Cryptosporidium sp. in dogs as well as to compare two techniques of fecal analysis. METHODS: Four-hundred and fifty canine fecal samples from the city of S?o Paulo were analyzed between 2003 and 2004. Fecal samples were randomly selected from dogs housed in a university veterinary hospital (group 1, n=200) and private kennels (group 2, n=250). The detection of Cryptosporidium was performed using modified Ziehl-Neelsen staining and Polymerase Chain Reaction (PCR) technique. Statistical analysis was performed using the two-tailed test of significance at 5% confidence interval (z critical=+/-1.645). RESULTS: Only Cryptosporidium parvum oocysts were found. The prevalences found by light microscopy examination and PCR techniques were 8.8% and 9.5%, respectively. Young animals showed a lower frequency (5.5%) compared to adults (10.1%). There was no statistically significant difference in Cryptosporidium prevalence between males and females. CONCLUSIONS: The prevalence of C. parvum in the canine population studied was similar to that one found in the literature and affects equally males and females. The use of PCR allowed the detection of more positive cases than light microscopy.     

Spatial distribution of endemic diseases in Ribeirão Preto, São Paulo State

The perception that some diseases happen in certain places is old. The concern in studying the relation between the human being and the environment resulted in several studies of medical geography, directed to the analysis of diseases spatial distribution. This sectional study was carried out in Ribeir?o Preto, S?o Paulo State, and aimed to illustrate, through health problems (dengue, leprosy and tuberculosis), how a Geographic Information System tool allows the identification of heterogeneous areas, providing support for the choice of strategies and specific interventions according to the need of residents, as well as, priority of resources to more vulnerable groups. The population comprised cases of dengue, leprosy and tuberculosis notified in Ribeir?o Preto in 2000. Data were collected in the Health Secretary Epidemiological Surveillance of the city. In order to obtain the thematic maps, data were geo-codified with the software MapInfo 7.8 e Spring 4.3. The thematic maps showed the density distribution of dengue, leprosy and tuberculosis cases in the city as a way to complement the analysis of health information, pointing priority areas for the control of these diseases.     

Prevalence of dental caries in schoolchildren in the rural area of Itapetininga, São Paulo State, Brazil

The present study is an attempt to characterize dental needs of the rural population in Itapetininga, S?o Paulo State, Brazil. One single dentist examined 291 children ages 5 and 12 years in rural schools, adopting WHO criteria for oral health surveys. Parents reported their children's socioeconomic characteristics and habits. Non-primary data gathered by the Brazilian health authority supplied information regarding the schoolchildren in the urban area of the town. Caries indices ranked as follows: dmft = 2.63 (5-year-old children) and DMFT = 2.45 (12-year-old children). The decayed component comprised 85.6% of the dmft and 34.2% of the DMFT, indicating limited utilization of dental treatment by children with decayed deciduous teeth. Caries prevalence was higher in rural schoolchildren than in their urban counterparts. Analysis of the results aims to improve planning of dental care.     

Low-income senior citizens in the Municipality of São Carlos, São Paulo State, Brazil: an epidemiological survey

This study focuses on the health profile of the elderly population in Sao Carlos, Sao Paulo State, Brazil, in 2003. The study population consisted of a sample over 60 years of age (n = 523) registered with the Family Health Program and the Unified National Health System. Point and interval prevalence of disabilities and chronic non-communicable diseases and cognitive status were estimated (95%CI). The study population was predominantly female with low education; 24.8% lacked any kind of retirement pension; 43.6% presented a low level of social integration; 46.7% required some form of help for 1 to 3 routine activities; 74.9% presented 1 to 5 chronic non-communicable diseases; and 56.2% scored under 24 on a cognitive test. Some 87.0% had sought health care and 22.4% required some kind of inpatient care. The results confirmed the need for improved professional training, adequacy of health services, and effective public policy to provide qualified health care for the elderly population.     

Sand flies in the Aguapeí river floodplain, northwest area of State of São Paulo, Brazil

OBJECTIVE: To investigate the seasonal variation of sand flies regarding their occurrences and densities. METHODS: The study was conducted in the Aguapeí river floodplain in the state of S?o Paulo, southeastern Brazil. Sand flies were monthly captured with automatic light traps set up between 18:00 and 7:00 hours, over a period of one year (2004-2005), at two sites: veranda of a domicile and in a forest on the banks of Aguapeí River. The Williams' average was used for estimating the seasonal variation and the Chi-square test for comparison. RESULTS: A total of 35,995 specimens were captured: five Brumptomyia avellari, one Psathyromyia (Xiphomyia) hermanlenti and the rest Nyssomyia neivai, which had the highest frequency during the winter. Ps. hermanlenti is first recorded in state of S?o Paulo. CONCLUSIONS: The high density of Nyssomyia neivai, a suspected vector of cutaneous leishmaniasis, points out to the risk of transmission of this disease in this setting, especially during drier periods of the year.     

Dengue fever: a post-epidemic sero-epidemiological survey in an urban area setting at a northwestern county of São Paulo State, Brazil

OBJECTIVE: The objective of this study was to evaluate the real size of the epidemics registered in the urban area of the county of Santa Bárbara D'Oeste, SP, Brazil, from April to June, 1995. The measurement of the epidemiological validity of the official surveillance system criteria and its positive predicted value were adopted as specific goals. METHODS: A sero-epidemiological survey was carried out over a sample of 1,113 sera from citizens of Santa Barbara D'Oeste, through a systematic random sampling of houses, five months after the end of the epidemics. Infection rates were compared with the infestation indexes by Aedes aegipty and the notified cases amongst the county sections. The importance of submitting patients with clinical suspicion of dengue to laboratory tests was discussed. RESULTS AND DISCUSSION: It was found that infection rates by dengue virus varied in the same direction and proportion as the presence of Aedes aegipty larvae reported by the "Breteau Index", as well as the number of cases reported by the official notifiable diseases surveillance system during the epidemics. A prevalence of 630 by 100 thousand inhabitants was found, a 15-fold rate when compared to the laboratory positive sera from cases detected by the surveillance system during the epidemics. A retrospective comparison with the surveillance reports, using serological results as a gold standard, also showed that the majority of dengue specific serum-positive individuals were not detected during the epidemics, otherwise cases that did not present serological reaction were notified exhibiting a low positive predictive value of clinical diagnosis (15,6).     

Inequality of workers' survival in Botucatu, São Paulo State, Brazil

The aim of this observational study was to estimate the survival function and risk of death in Botucatu, Southeast Brazil, by occupation. The occupational history of inhabitants of Botucatu who died after their 10th birthday from January 1, 1997, to March 31, 1998, was analyzed, as were the occupational histories of workers' spouses. A total of 992 subjects were studied. Data were analyzed by fitting a proportional hazards model where the time variable was age at death or at time of interview and the main co-variable was occupation. Results showed that risk of death increased consistently as the level of occupational specialization decreased, displaying a 12-year increase in life expectancy for professional as compared to unskilled workers.     

Prevalence of obesity in preschool children from five towns in São Paulo State, Brazil

Health and nutritional characteristics of children under 5 years of age were investigated through a cross-sectional study in 5 small cities from different regions in the State of Sao Paulo, Brazil, which displayed different socioeconomic profiles: Bady Bassit, Bofete, Jaborandi, Morungaba, and Riversul. Data were obtained using a systematic sampling from the 1991 National Census. Anthropometric data were collected from all children under 5 years of age living in the selected households. Nutritional status was determined by height/age and weight/height according to the National Center for Health Statistics -- NCHS standards. Stunting was defined as HAZ below -- 2 Z scores and obesity as WHZ above 2 Z scores. The study sample consisted of 987 children (490 boys and 497 girls). Prevalence of obesity was 6.6% (65) and stunting 5.0% (51). Per capita income displayed a significant and positive association with obesity (p = 0.018), in contrast to an inverse association with stunting (p = 0.038).     

Asthma mortality in the city of São Paulo,Brazil

OBJECTIVE: To quantify and compare asthma mortality rates as the main cause of death, taking into consideration the following variables: sex, age and seasonality. METHODS: Data was collected from all death certificates coded 493 of people aged 5 to 34 years in the periods of 1983-5 and 1993-5 in the city of S?o Paulo, SP, Brazil. Data analysis was performed by directly comparing death rates and identifying the odds ratio trend and directly comparing the numbers of asthma deaths. RESULTS: There was no increase in asthma mortality rates for the study periods. There was no difference between men and women. A greater number of deaths in the age group 20 to 34 years were observed. Seasonality was more evident in the first period studied. CONCLUSIONS: Differing from reports in other countries, the results did not show any increase in asthma mortality rates, The variable sex didn't seem to interfere with mortality. Deaths are more frequent among young adults, and their risk may be 9 times greater than that of young children. Deterioration of social and economic issues and health care services and even climatic changes may have been implicated in the absence of seasonality as a risk factor for asthma mortality. The disease by itself is not considered by many health professionals as critical in order to explain the chain of events that lead to death.     

Comparison of two methodologies for detection of Giardia spp. cysts and Cryptosporidium spp. oocysts in activated sludge samples from a sewage treatment plant in the city of Campinas, São Paulo State, Brazil

Giardia spp. and Cryptosporidium spp. are recognized worldwide as highly infectious protozoan parasites that can cause severe gastrointestinal disease in humans and animals. The detection of these pathogens in activated sludge samples becomes interesting since there is an increasing trend for the use of sewage sludge (biosolids) in agriculture. A total of 22 samples were collected and evaluated by means of Centrifugal - Concentration, followed or not followed by a purification process (ether clarification and sucrose flotation). Student t tests for comparison of the two procedures indicated a higher recovery rate of Giardia cysts with Centrifugal - Concentration; with regard to Cryptosporidium oocysts, no significant differences were found between the two methods, as only two samples were positive. The Centrifugal - Concentration procedure was shown to be the simplest and cheapest to perform, as emphasized by the efficiency recovery results.     

Cytomegalovirus seroepidemiology in an urban community of São Paulo, Brazil

INTRODUCTION: After the era of rubella vaccine, cytomegalovirus (CMV) infection is one of the most frequently causes of mental retardation and congenital deafness. Seroepidemiological studies are necessary to understand the transmission dynamics of the disease. The purpose of the study was to quantify the transmission rate of CMV disease in a community in the state of S?o Paulo, Brazil. METHODS: Using ELISA test (IgG), a retrospective serological survey looking for CMV antibodies was performed in an non-immunized community. Frozen sera from 443 individuals, randomly selected by cluster sampling technique in the town of Caieiras, S?o Paulo, were collected from November 1990 to January 1991. Seroprevalence was stratified by age (0-40 years). Mathematical techniques were applied to determine the age-dependent decay function of maternal antibodies during the first year of life, the age-dependent seroprevalence function and the force of infection for CMV in this community. RESULTS: It was observed a descending phase of seropositivity in the first 9 months, but changes in antibody titration were observed between 8 months old and one year of age. The average age of the first infection was 5.02 months of age and 19.84 years, when the age-dependent seroprevalence and the force of infection were analyzed between 10 months of age and 10 years of age and from 10 to 40 years old, respectively. CONCLUSION: CMV infection is highly prevalent among the population studied and infection occurs in the first year of life. This study shows that most women at reproductive age are vulnerable to the first infection, increasing the risk for congenital infection.