Asymptomatic carriers of Plasmodium spp. as infection source for malaria vector mosquitoes in the Brazilian Amazon

We have described the existence of asymptomatic carriers of Plasmodium vivax and Plasmodium falciparum infections in native Amazon populations. Most of them had low parasitemias, detected only by polymerase chain reaction (PCR). Because they remain symptomless and untreated, we wanted to determine whether they could infect Anopheles darlingi Root, the main Brazilian vector, and act as disease reservoirs. Fifteen adult asymptomatic patients (PCR positive only) were selected, and experimental infections of mosquitoes were performed by direct feeding and by a membrane-feeding system. Seventeen adult symptomatic patients with high parasitemias were used as controls. We found an infection rate in An. darlingi of 1.2% for the asymptomatic carriers and 22% for the symptomatic carriers. Although the asymptomatic group infected mosquitoes at a much lower rate, these patients remain infective longer than treated, symptomatic patients. Also, the prevalence of asymptomatic infections is 4 to 5 times higher than symptomatic infections among natives. These results have implications for the malaria control program in Brazil, which focuses essentially on the treatment of symptomatic patients. © 2005 Entomological Society of America.

Infection by Mycobacterium leprae of household contacts of lepromatous leprosy patients from a post-elimination leprosy region of Colombia

The Leprosy Control Program of Antioquia, (post-elimination leprosy state of Colombia), had registered by 1999, 56 lepromatous leprosy patients and their household contacts (HHC). Our interest was to detect Mycobacterium leprae infection in these HHC. Clinical examination, acid-fast bacillary staining (AFB) in nasal secretions, and slit skin samples, IgM anti-PGL-I in serum and Lepromine A (Mitsuda) reactivity were tested. Two hundred forty eight HHC were studied, 49% were male. After clinical examination, two HHC were diagnosed as multi bacillary patients; 13% showed positive IgM anti-PGL-I titers; Mitsuda reaction (> 4 mm) was positive in 59%; AFB was negative in all samples, except in the two new patients. HHC were classified according to test results.Group 1: two new multi bacillary patients. Group 2: 15 HHC seropositive, Mitsuda-negative. Group 3: 13 HHC seropositive, Mitsuda-positive. Group 4: 130 HHC seronegative, Mitsuda-positive. Group 5: 88 HHC seronegative, Mitsuda-negative. These results are an indication that the transmission of the infection is still happening in a region considered in the post elimination phase. The two new patients represent an infection source for others contacts, and groups 2 and 3 are infected HHC that could develop the disease in future. Follow up of high risk population is necessary to achieve real elimination of leprosy.

Chlamydophila psittaci and Toxoplasma gondii infection in pigeons (Columba livia) from São Paulo State, Brazil

Pigeons (Columba livia) cohabit with humans in urban and rural areas, representing a public health problem since microorganisms are transmitted through the inhalation of dust from their dry feces (chlamydiosis) and through ingestion of their undercooked or poorly refrigerated meat (toxoplasmosis). This study aimed to evaluate the presence of Chlamydophila psittaci and Toxoplasma gondii in pigeons from four cities in São Paulo State, Brazil. C psittaci was evaluated through hemi-nested polymerase chain reaction (hnPCR) using cloacal and tracheal swabs, whereas T. gondii specific antibodies were assessed by means of modified agglutination test (MAT), mouse brain and muscle bioassay, and polymerase chain reaction (PCR). To confirm the infection in mice, T. gondii antibodies were assayed by using indirect fluorescent antibody test (IFAT). Considering C. psittaci, 40/238 (16.8%; 95%CI 12.6-22.1%) samples were positive according to hnPCR, especially for the cities of São Paulo (42.5%) and Bauru (35%). As regards T. gondii, 12/238 (5%; 95%CI 2.9-8.6%) serum samples were positive according to MAT. of these, five samples had titer equal to 1:8; six samples, 1:16; and one sample, 1:32. Bioassay, IFAT and PCR were negative for mouse toxoplasmosis. The absence of T. gondii antibodies suggests that pigeons may be infected with a low concentration of the agent, not detected by the antigen test. Thus, C. psittaci represents an actual problem concerning bird health. (C) 2010 Elsevier B.V. All rights reserved.

Characterization of Leishmania infantum species in dogs from the urban area of Cuiabá, State of Mato Grosso, Brazil

INTRODUCTION: Visceral leishmaniasis presents urban behavior in some Brazilian cities, with domestic dogs as the main infection source. In Cuiabá, MT, canine visceral leishmaniasis was diagnosed and characterized as recommended by the Ministry of Health. METHODS: Biological samples from suspected canine carriers were analyzed by the isoenzyme electrophoresis technique. The 6PGDH enzyme and reference strain IOC/L0566 (MHOM/BR/1975/M2903) of Leishmania (Leishmania) infantum was used as one of the controls. RESULTS: Electrophoresis analysis revealed that the canine isolates belonged to the species L. (L.) infantum. CONCLUSIONS: The authors emphasize the importance of species characterization, particularly in areas of mixed infection like Cuiabá.

Molecular characterisation of Sporothrix schenckii isolates from humans and cats involved in the sporotrichosis epidemic in Rio de Janeiro, Brazil

An epidemic of sporotrichosis, a subcutaneous mycosis caused by the fungus Sporothrix schenckii, is ongoing in Rio de Janeiro, Brazil, in which cases of human infection are related to exposure to cats. In an attempt to demonstrate the zoonotic character of this epidemic using molecular methodology, we characterised by DNA-based typing methods 19 human and 25 animal S. schenckii isolates from the epidemic, as well as two control strains. To analyse the isolates, the random amplified polymorphic DNA (RAPD) technique was performed using three different primers, together with DNA fingerprinting using the minisatellite derived from the wild-type phage M13 core-sequence. The analyses generated amplicons with considerable polymorphism. Although isolates exhibited high levels of genetic relatedness, they could be clustered into 5-10 genotypes. The RAPD profiles of epidemic S. schenckii isolates could be distinguished from that of the United States isolate, displaying 20% similarity to each primer and 60% when amplified with the M13 primer. DNA fingerprinting of S. schenckii isolated from the nails (42.8%) and the oral cavities (66%) of cats were identical to related human samples, suggesting that there is a common infection source for animals and humans in this epidemic. It is clear that cats act as a vehicle for dissemination of S. schenckii.

Vigilancia ambiental de casos esporádicos de legionelosis en el municipio de Córdoba (España), 2005-2010

We examined the information of legionellosis surveillance system in the municipality of Cordoba (Spain) as a preventive resource for environmental health management and describes the public health implications of sporadic cases investigations. A multidisciplinary team analyzed information on surveillance of water sites potentially contaminated by Legionella and clinical data of the patients classified like community case; mapping patient's home address using geographic information systems (GIS). Legionella pneumophila serogroup 1 was identified in 31 sporadic cases. 53 suspected sources, mainly cooling towers have been investigated. In no event is managed to locate infection source even if poorly maintained systems, structural deficiencies and operational failures were apparent. The use of GIS allowed us to identify two geographic areas where cases are concentrated within one radius of less than 500 meters. The finding of two suspected urban advised to reorient the preventive strategy in public health

Characteristics and determinants of outcome of hospital-acquired bloodstream infections in intensive care units: the EUROBACT International Cohort Study.

PURPOSE: The recent increase in drug-resistant micro-organisms complicates the management of hospital-acquired bloodstream infections (HA-BSIs). We investigated the epidemiology of HA-BSI and evaluated the impact of drug resistance on outcomes of critically ill patients, controlling for patient characteristics and infection management. METHODS: A prospective, multicentre non-representative cohort study was conducted in 162 intensive care units (ICUs) in 24 countries. RESULTS: We included 1,156 patients [mean ± standard deviation (SD) age, 59.5 ± 17.7 years; 65 % males; mean ± SD Simplified Acute Physiology Score (SAPS) II score, 50 ± 17] with HA-BSIs, of which 76 % were ICU-acquired. Median time to diagnosis was 14 [interquartile range (IQR), 7-26] days after hospital admission. Polymicrobial infections accounted for 12 % of cases. Among monomicrobial infections, 58.3 % were gram-negative, 32.8 % gram-positive, 7.8 % fungal and 1.2 % due to strict anaerobes. Overall, 629 (47.8 %) isolates were multidrug-resistant (MDR), including 270 (20.5 %) extensively resistant (XDR), and 5 (0.4 %) pan-drug-resistant (PDR). Micro-organism distribution and MDR occurrence varied significantly (p < 0.001) by country. The 28-day all-cause fatality rate was 36 %. In the multivariable model including micro-organism, patient and centre variables, independent predictors of 28-day mortality included MDR isolate [odds ratio (OR), 1.49; 95 % confidence interval (95 %CI), 1.07-2.06], uncontrolled infection source (OR, 5.86; 95 %CI, 2.5-13.9) and timing to adequate treatment (before day 6 since blood culture collection versus never, OR, 0.38; 95 %CI, 0.23-0.63; since day 6 versus never, OR, 0.20; 95 %CI, 0.08-0.47). CONCLUSIONS: MDR and XDR bacteria (especially gram-negative) are common in HA-BSIs in critically ill patients and are associated with increased 28-day mortality. Intensified efforts to prevent HA-BSIs and to optimize their management through adequate source control and antibiotic therapy are needed to improve outcomes.

Mandatory infectious diseases consultation for MRSA bacteremia is associated with reduced mortality.

OBJECTIVES: Although infectious disease (ID) consultation has been associated with lower mortality in Staphylococcus aureus bloodstream infections, it is still not mandatory in many centers. This study aimed at assessing the impact of ID consultation on diagnostic and therapeutic management of methicillin-resistant S. aureus (MRSA) bacteremia. METHODS: Retrospective cohort study of all patients with MRSA bacteremia from 2001 to 2010. ID consultations were obtained on request between 2001 and 2006 and became mandatory since 2007. RESULTS: 156 episodes of MRSA bacteremia were included, mostly from central venous catheter (32%) and skin and soft tissue (19%) infections. ID consultation coverage was 58% between 2001 and 2006 and 91% between 2007 and 2010. ID consultation was associated with more echocardiography (59% vs. 26%, p < 0.01), vancomycin trough level measurements (99% vs. 77%, p < 0.01), follow-up blood cultures (71% vs. 50%, p = 0.05), deep-seated infections (43% vs. 16%, p < 0.01), more frequent infection source control (83% vs. 57%, p = 0.03), a longer duration of MRSA-active therapy (median and IQR: 17 days, 13-30, vs. 12, 3-14, p < 0.01) and a 20% reduction in 7-day, 30-day and in-hospital mortality. CONCLUSIONS: ID consultation was associated with a better management of patients with MRSA bacteremia and a reduced mortality.

Sorologia Anti PGL-1 e risco de ocorrência de hanseníase em área de alta endemicidade do Estado de São Paulo: quatro anos de seguimento

Os testes sorológicos para diagnóstico de hanseníase, usando o glicolipídeo-fenólico-1 (PGL-1), considerado antígeno específico do M. leprae, têm aberto algumas possibilidades de estudo do comportamento epidemiológico desta doença. Algumas questões, como tempo de latência da doença, infecção subclínica e importância do contato intra-domiciliar (contatos) no controle da endemia, puderam ser melhor analisadas usando este instrumental. Este estudo teve por objetivo verificar a existência de associação entre a situação sorológica e a ocorrência de hanseníase. Foram seguidas, durante 4 anos, 6.520 pessoas com idade igual ou superior a 5 anos, submetidas no início do seguimento ao teste sorológico Anti PGL-1, pertencentes ao universo de 7.416 habitantes da área urbana de um município paulista caracterizado por elevada endemicidade de hanseníase. Foi identificado um grupo de 590 indivíduos soropositivos (9,0 %). Foram diagnosticados, no período, 82 casos novos de hanseníase, 26 no grupo de soropositivos (441 casos novos/10.000 indivíduos) e 48 no de soronegativos (81/10.000). Entre os que não fizeram sorologia, surgiram 8 casos novos (89/10.000). Procurou-se controlar, na análise, a condição de contato, dado que a taxa de soropositividade padronizada por idade e sexo era de 9,61% no grupo de contatos e 7,65% no de não-contatos. Tomando-se os não-contatos soronegativos como o grupo de não expostos, foram calculados os riscos relativos de adoecimento no período, a partir das taxas de detecção padronizadas por idade, resultando no seguinte: os contatos ID soropositivos apresentaram a taxa de 1.704/10.000, 27 vezes maior que a dos não-expostos, igual a 63/10.000; os não-contatos soropositivos e os contatos soronegativos apresentaram taxas, respectivamente, de 274 e 198/10.000, ambas maiores que as dos não-expostos e iguais entre si. A soropositividade associou-se à elevação de 8,6 vezes do risco de hanseníase entre os contatos e de 4,4 entre os não-contatos. Na situação epidemiológica estudada, caracterizada por elevada endemicidade de hanseníase, 50% dos casos novos surgiram entre os não-contatos soronegativos, ou seja, sem fonte de infecção conhecida. Portanto, o teste anti-PGL-1 usado revela-se, na prática, de pouca aplicabilidade. Resta estudar ainda o comportamento da sorologia anti-PGL-1 em áreas de média e baixa endemicidade para que se possa tirar conclusões mais consubstanciadas sobre sua utilidade no controle da endemia. Recomenda-se o aprofundamento das pesquisas sorológicas e de outras que aprimorem o diagnóstico precoce da infecção subclínica, inclusive para detecção de formas paucibacilares, para se ampliar as possibilidades de influir no controle endêmico.

Relevance of Budgerigars (Melopsittacus undulatus) in Experimental Epidemiology of Newcastle Disease.

This study was carried out to clarify the real role that was played by the budgerigars (Melopsittacus undulatus) in the epidemiological plan, under the perspective of its being an infection source of the Newcastle Disease Virus (NDV). For this, the study used Specific-Pathogen-Free chicks (SPF) that were housed with budgerigars that were inoculated with a pathogenic strain (velogenic viscerotropic) of NDV (EID5o =10815/0.1 mL) pathogenic to chickens, by the ocular-nasal via. Each group was composed by 10 SPF chicks and 5 budgerigars. After 5 days of the inoculation of the budgerigars with NDV, SPF chicks were put together with each group of budgerigars, so that there was a direct contact between both species. Cloaca) swabs and blood samples were collected in both species (budgerigars and SPF chicks) after 13 and 19 days post-challenge, respectively, for genome viral excretion by Reverse Transcription Polymerase Chain Reaction (RTPCR) and antibody's search by the inhibition of hemmaglutination test (HI). Budgerigars did not demonstrate any clinical signs of Newcastle Disease (ND). They were refractory to the clinical disease with the NDV. However, antibody titres from inhibition of Hemagglutination (HI) test were detected 9 and 21 days after challenge. Therefore, it was demonstrated the state of carrier of NDV in this species. In SPF chicks allocated with infected budgerigars, NDV genome was detected 13 and 19 days after challenge. Thus, the transmission of the pathogenic virus from the budgerigars to SPF chicks that were housed together was evident until 19 days of the experimental infection with this pathogen. This reveals the importance of the budgerigars from the epidemiological point of view as a potential source of infection of the NDV to commercial chickens that could be raised near this species.

Prevalência de Cryptosporidium sp. em cães de instituições da cidade de São Paulo

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 São 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.

Surto de salmonella enteritidis/enteridis em granja produtora de frango caipira na região sul do maranhão

The aim of this trial was to detect the agent that causes high mortality of chickens in a farm in the south of Maranhão, Brazil, as well as determining the infection source. Necropsy of the chickens was done and carried through bacteriological analyses of liver, intracardiac blood and chicken food. The samples taken from the heart blood, liver and initial chicken feed had presented characteristic colonies of Salmonella. These colonies had been submitted to the biochemical and serologic tests for evidence of the patogenicity. Salmonelosis is considered an important disease in the poultry keeping and can cause serious ambient and economic losses, beyond the problem of public health. This paper stands out the importance of a good sanitary handling and programs of control and prevention of illnesses in the animal breeding.

Acidentes rábicos em município do norte do Paraná: uma análise do perfil, conduta e sistema de notificação

Pós-graduação em Saúde Coletiva - FMB

Detecção de Toxoplasma gondii em linguiças suínas tipo frescal, comercializadas no município de Botucatu - SP

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Estudo epidemiológico da Leishmaniose Tegumentar Americana (LTA) no Estado do Amapá estratificado em regiões de risco no período de 2002 a 2006

A Leishmaniose Tegumentar Americana no estado do Amapá ainda está restrita às áreas rurais. Para estratificar o Amapá em áreas de risco para LTA, e conhecer seu perfil epidemiológico, foram coletados casos registrados no Sistema de Informação Nacional de Agravos de Notificação e classificados os municípios quanto ao risco, de acordo com as médias dos coeficientes de prevalência de 2002 a 2006 de cada município. Foram registrados 2.664 casos autóctones de LTA: 2002 (353 casos); 2003 (481); 2004 (968), 2005 (422) e 2006 (440). Desses, 653 (24,5%) com origem da infecção no município de Porto Grande. A média do coeficiente de prevalência do estado nos 5 anos estudados foi de 95,51/100.000hab. Os municípios foram agrupados em áreas quanto ao grau de risco: de baixo risco para LTA (Macapá, Cutias, Santana e Amapá); médio risco (Itaubal, Pracuúba, V. do Jari e Ferreira Gomes); alto risco (L. do Jari, Mazagão, Tartarugalzinho e Oiapoque) e muito alto risco (Calçoene, P. Grande, P. B. do Amapari e S. do Navio). O Amapá apresentou 72% dos casos no 1ºsemestre, com 16,6% dos casos no mês de abril; 38,8% em pacientes com idade entre 20 a 34 anos; 79,7% de ocorrência no sexo masculino, variando na área de médio risco 83% e baixo risco 72%; 29% em pacientes com escolaridade de 4 a 7 anos de estudo. Com 96,2% com confirmação laboratorial na área de muito alto risco; 98,9% casos de leishmaniose cutânea e apenas 42,9% com cura confirmada, na área de alto risco ocorreram 65,3% de cura. A LTA apresenta 100% de autoctonia no estado do Amapá, com um importante surto em 2004 e o município de P. Grande é o que mais contribui para a manutenção desta endemia.