Chronic carriers of hepatitis B surface antigen in an endemic area for schistosomiasis mansoni in Brazil

Data on the association of schistosomiasis and hepatitis B in field-based studies are scarce. Two areas have been selected for this study: i) Queixadinha, endemic for schistosomiasis, with a population of 693 individuals, and ii) Capão, a control non-endemic area, with 515 inhabitants. Sera of all individuals in both areas were tested for hepatitis B infection, yearly, from 1994 to 1997. In the first area hepatitis B was found in 32.1% of children up to one year old and reached a peak of 68.7% in the age range of 15 to 19 years. In the control area the prevalence of hepatitis B was under 5% up to 19 years of age and the highest prevalence was observed in adults over 45. HBsAg was detected in 9.4% of the individuals living in the endemic area for schistosomiasis and in 1.4% of the controls (OR=4.98; 95%CI=3.7-6.7). The index of chronicity of HBsAg was not statistically different in the studied areas (8.1% x 7.3%; OR = 1.09; 95%CI= 0.42-3.03), nor was it different for people with and without schistosomiasis in Queixadinha (8.7% x 7.0%). We conclude that the Schistosoma mansoni infection has not altered the course of hepatitis B in the studied area.

Eimeria curvata n. sp.(Apicomplexa: Eimeriidae) in Columbina talpacoti and Scardafella squammata (Aves: Columbidae) from Brazil

Eimeria curvata is a new coccidian described in the doves Columbina talpacoti and Scardafella squammata from western of the State of São Paulo, Brazil. The oocysts are ovoid to ellipsoid, 18.3 (17-19) µm x 15.5 (15-17) µm, with a shape index of 1.2 (1.1-1.3). The wall is colorless, smooth and double-layered. A polar granule is present, but there is no micropyle or oocyst residuum. The sporocysts are elongate, 12.3 (11.5-13) µm x 5.8 (5.5-6) µm with a curved anterior portion and a smooth, thin, single-layered wall. The Stieda body is protuberant and nipple-like; there is no substieda body. The sporozoites lie head-to-tail in the sporocyst and contain a large refractile body at the extremities. The sporocyst residuum contains small granules uniformly distributed in the middle of the sporocyst. The prevalence of E. curvata n. sp. was 17.4% and 12.8% in C. talpacoti and S. squammata, respectively.

Mutations in the rpoB gene of rifampicin-resistant Mycobacterium tuberculosis strains isolated in Brazil and France

We evaluated the mutations in a 193bp of the rpoB gene by automated sequencing of rifampicin (RMP)-resistant and susceptible Mycobacterium tuberculosis strains isolated from Brazil (25 strains) and France (37 strains). In RMP-resistant strains, mutations were identified in 100% (16/16) from France and 89% (16/18) from Brazil. No mutation was detected in the 28 RMP-susceptible strains. Among RMP-resistant or RMP-susceptible strains deletion was observed. A double point mutation which had not been reported before was detected in one strain from France. Among French resistant strains mutations were found in codons 531 (31.2%), 526, 513 and 533 (18.7% each). In Brazilian strains the most common mutations were in codons 531 (72.2%), 526 (11.1%) and 513 (5.5%). The heterogeneity found in French strains may be related to the fact that most of those strains were from African or Asian patients.

Mycobacterium bovis: polymerase chain reaction identification in bovine Lymphonode biopsies and genotyping in isolates from Southeast Brazil by spolygotyping and restriction fragment length polymorphism

Diagnosis of the Mycobacterium tuberculosis complex by direct PCR of mediastinal lymphnode DNA and microbiological tests were compared in cattle suspicious of bearing tuberculous-like lesions detected during slaughter. The PCR procedure applied on DNA samples (n=54) obtained by adding alpha -casein into the thiocyanate extraction mix was positive in 70% of the samples. PCR confirmed the identification of 23 samples (100%) that grew in culture, 9 samples (60%) that failed to grow in culture, plus 6 (37.5%) samples that resulted in growth of bacterial contaminants. Genotyping by IS6110-RFLP and DR-spoligotyping analysis of seven samples revealed the presence of several polimorphisms. Seven of the isolates contained multiple copies of IS6110, thus defining the existence of five singular genotypes.

Drug resistance and genotypes of strains of Mycobacterium tuberculosis isolated from human immunodeficiency virus-infected and non-infected tuberculosis patients in Bauru, São Paulo, Brazil

Little is known about transmission and drug resistance of tuberculosis (TB) in Bauru, State of São Paulo. The objective of this study was to evaluate risk factors for transmission of Mycobacterium tuberculosis strains in this area. Strains were collected from patients attended at ambulatory services in the region and susceptibility towards the main first line antibiotics was determined and fingerprinting performed. A total of 57 strains were submitted to susceptibility testing: 23 (42.6%) were resistant to at least one drug while 3 (13%) were resistant against both rifampicin and isoniazide. Resistant strains had been isolated from patients that had not (n = 13) or had (n = 9) previously been submitted to anti-TB treatment, demonstrating a preoccupying high level of primary resistance in the context of the study. All strains were submitted to IS6110 restriction fragment length polymorphism (IS6110-RFLP) and double repetitive element PCR (DRE-PCR). Using IS6110-RFLP, 26.3% of the strains were clustered and one cluster of 3 patients included 2 HIV-infected individuals that had been hospitalized together during 16 days; clustering of strains of patients from the hospital was however not higher than that of patients attended at health posts. According to DRE-PCR, 55.3% belonged to a cluster, confirming the larger discriminatory power of IS6110-RFLP when compared to DRE-PCR, that should therefore be used as a screening procedure only. No clinical, epidemiological or microbiological characteristics were associated with clustering so risk factors for transmission of TB could not be defined in the present study.

Therapy of tungiasis: a double-blinded randomized controlled trial with oral ivermectin

Tungiasis is an ectoparasitosis causing considerable pathology in endemic areas. Standard therapy consists of removing the embedded parasite with a sterile needle. There is no effective chemotherapy at hand. To fill this gap, a double-blinded randomized controlled trial with oral ivermectin was conducted. A total of 54 individuals (27 in the placebo group, 27 in the ivermectin group) was followed up for seven days. They presented a total of 192 lesions. Patients received either ivermectin (300 µg/kg body weight at a single dose, repeated after 24 h) or placebo. Outcome measures included the clinical stage of lesion, presence of erythema, pain, itching, signs of viability of the parasite, and total lysis of flea. The ratio of fleas with total lysis per total number of fleas was slightly higher in the ivermectin group; however, this difference was not statistically significant. There was no significant difference in any of the other outcome measures between the treatment and the placebo group. The results show that oral ivermectin is without any clinically significant efficacy against embedded sand fleas at the dose given.

Seropositivity for hepatitis B virus, vaccination coverage, and vaccine response in dentists from Campo Grande, Mato Grosso do Sul, Brazil

This study investigated the seropositivity for hepatitis B virus (HBV), the vaccination index, and the vaccine response index in dentists from Campo Grande, MS. Blood samples from 474 dentists (63.7% women and 36.3% men), with a mean age of 38.5 ± 10.5 years were analyzed by enzyme-linked immunosorbent assay to detect the serological markers: HBsAg, anti-HBs, and anti-HBc. The HBsAg positive samples were tested for anti-HBc IgM, HBeAg, and anti-HBe. A total of 51 (10.8%) dentists showed seropositivity for HBV. Three (0.6%) were HBsAg/anti-HBc/anti-HBe positive, 43 (9.1%) were anti-HBc/anti-HBs positive, and 5 (1.1%) had only anti-HBc. Viral DNA was detected by polymerase chain reaction in 9 (17.6%) out of 51 HBV seropositive samples. A vaccination index of 96.6% (458/474) was observed, although 73.1% (335/458)completed the three-dose schedule. Excluding 46 HBV seropositive individuals from 458 that reported vaccination, 412 were analyzed for vaccine response index. It was observed that 74.5% (307/412) were anti-HBs positive; this percentage increased to 79.1% when three doses were administered. The results showed a high vaccination index and a good rate of vaccine response; however, the failure in completing the three-dose schedule and the occurrence of HBV infection reinforce the need for more effective prevention strategies.

The girl from the Church of the Sacrament: a case of congenital syphilis in XVIII century Lisbon

Syphilis is a sexually or congenitally transmitted infectious disease with an impact on the health of human populations that has undergone important cycles in different countries and periods of history. Its presence was first diagnosed in Europe in the late XIV century. In Portugal, although there are various written records of the infection in the last centuries, there are rare references to it in archeological findings (mummified bodies are also rare in Portugal). The current study describes a probable case of congenital syphilis in an 18-month-old girl buried in the Church of the Sacrament in Lisbon. Her body, dating to the XVIII century, was found mummified together with dozens of others, still not studied. Symmetrical periostitis of the long bones, osteitis, metaphyseal lesions, left knee articular, and epiphyseal destruction, and a rarefied lesion with a radiological appearance compatible with Wimberger's sign all point to a diagnosis of congenital syphilis. The diagnosis of this severe form of the infection, possibly related to the cause of death in this upper-class girl, calls attention to the disease's presence in XVIII century Lisbon and is consistent with the intense mobilization at the time in relation to the risks posed by so-called heredosyphilis. It is the first case of congenital syphilis in a child reported in archeological findings in Portugal, and can be correlated with other cases in skeletons of adults buried in cemeteries in Lisbon (in the XVI to XVIII centuries) and Coimbra (XIX century). Finally, this finding highlights the need to study the entire series of mummified bodies in the Church of the Sacrament in order to compare the paleopathological findings and existing historical documents on syphilis, so as to expand the paleoepidemiological knowledge of this infection in XVIII century Lisbon.

Typing of Mycobacterium tuberculosis strains isolated in Community Health Centers of Rio de Janeiro City, Brazil

Fingerprinting of Mycobacterium tuberculosis strains from tuberculosis (TB) patients attended in Community Health Centers (CHCs) of Rio de Janeiro was performed to verify possible risk factors for TB transmission. A prospective community-based study was performed during the period of July 1996 to December 1996 by collecting sputum samples of 489 patients in 11 different CHCs in four different planning areas (APs) of the city. Bacteriological, clinical, and epidemiological information was collected and M. tuberculosis genotypes defined after restriction fragment length polymorphism (IS6110-RFLP) and double repetitive element (DRE) fingerprinting of RFLP-clustered cases. Risk factors for TB transmission were looked for using three levels of cluster stringency. Among 349 (71%) positive cultures obtained, IS6110-RFLP typing could be performed on strains from 153 different patients. When using identity of RFLP patterns as cluster definition, 49 (32%) of the strains belonged to a cluster and none of the clinical or epidemiologic characteristics was associated with higher clustering levels. However, higher clustering level was observed in the AP including the central region of the city when compared to others. This strongly suggests that more recent transmission occurs in that area and this may be related with higher incidence of TB and HIV in this region.

Ribotyping and virulence markers of Yersinia pseudotuberculosis strains isolated from animals in Brazil

Ribotyping and virulence markers has been used to investigate 68 Yersinia pseudotuberculosis strains of serogroups O:1a and O:3. The strains were isolated from clinical material obtained from healthy and sick animals in the Southern region of Brazil. Ribotypes were identified by double digestion of extracted DNA with the restriction endonucleases SmaI and PstI, separation by electrophoresis and hybridization with a digoxigenin-labeled cDNA probe. The presence of the chromosomal virulence marker genes inv, irp1, irp2, psn, ybtE, ybtP-ybtQ, and ybtX-ybtS, of the IS100 insertion sequence, and of the plasmid gene lcrF was detected by polymerase chain reaction. The strains were grouped into four distinct ribotypes, all of them comprising several strains. Ribotypes 1 and 4 presented distinct profiles, with 57.3% genetic similarity, ribotypes 2 and 3 presented 52.5% genetic similarity, and genetic similarity was 45% between these two groups (1/4 and 2/3). All strains possessed the inv, irp1, and irp2 genes. Additionally, strains of serogroup O:1a carried psn, ybtE, ybtP-ybtQ, ybtX-ybtS, and IS100. As expected lcrF was only detected in strains harboring the virulence plasmid. These data demonstrate the presence of Y. pseudotuberculosis strains harboring genotypic virulence markers in the livestock from Southern Brazil and that the dissemination of these bacteria may occur between herds.

Molecular diversity of serial Cryptococcus neoformans isolates from AIDS patients in the city of São Paulo, Brazil

Despite highly active anti-retroviral therapy, cryptococcal meningoencephalitis is the second most prevalent neurological disease in Brazilian AIDS patients, being frequently a defining condition with several episodes. As knowledge of Cryptococcus neoformans isolates in the same episode is critical for understanding why some patients develop several episodes, we investigated the genotype characteristics of C. neoformans isolates in two different situations. By pulsed field gel electrophoresis and random amplifield polymorphic DNA analysis, 54 isolates from 12 patients with AIDS and cryptococcosis were analyzed. Group 1 comprised 39 isolates from nine patients with a single episode and hospitalization. Group 2 comprised 15 isolates from three patients with two episodes and hospitalizations. Except for three patients from group 1 probably infected with a single C. neoformans isolate, the other nine patients probably were infected with multiple isolates selected in different collection periods, or the infecting isolate might have underwent mutation to adapt and survive the host immune system and/or the antifungal therapy. However, the three patients from group 2 presented genetic diversity among isolates collected in both hospitalizations, possibly having hosted the initial isolate in both periods. These data, emphasize that Cryptococcus diversity in infection can contribute to strategies of treatment and prevention of cryptococcosis.

High proportion of hepatitis C virus genotypes 1 and 3 in a large cohort of patients from Southern Brazil

Hepatitis C virus (HCV) isolates have been divided into six genotypes (1 to 6). The duration of hepatitis C standard treatment is 48 weeks for patients infected with HCV genotype 1 vs 24 weeks for those infected with genotypes 2 and 3. A total of 1544 HCV isolates from chronic patients living in the southern Brazilian states of Rio Grande do Sul (RS, n = 627) and Santa Catarina (SC, n = 917) were genotyped by restriction fragment length polymorphism (RFLP) of polymerase chain reaction (PCR) products. In RS, 338 (53.9%; 95% CI 50.0 - 57.8%), 34 (5.4%; 95% CI 3.8 - 7.4%) and, 255 (40.7%; 95% CI 36.9 - 44.6%) samples were from genotypes 1, 2, and 3, respectively. In SC, 468 (51%; 95% CI 47.8 - 54.2%), 26 (2.9%; 95% CI 1.9 - 4.1%) and, 423 (46.1%; 95% CI 42.9 - 49.3%) samples were from genotypes 1, 2, and 3, respectively. Genotyping results were confirmed by direct nucleotide sequencing of PCR products derived from 68 samples, without any discrepancy between PCR-RFLP and nucleotide sequencing methods. In conclusion, almost half of the hepatitis C patients from South of Brazil are infected by genotypes 2 and 3 and, these results have important consequential therapeutic implications as they can be treated for only 24 weeks, not 48.

Prevalence and genotyping of hepatitis C virus in blood donors in the state of Pará, Northern Brazil

Given the scarcity of epidemiological information on hepatitis C virus (HCV) infection in Northern Brazil, we determined the prevalence and genotypic frequency in blood donors in the state of Pará (PA). Blood samples from all of the blood donors at the Fundação HEMOPA (blood bank of PA) from 2004-2006 were screened for the presence of antibodies to anti-HCV and samples seroreactive to anti-HCV were further tested for HCV RNA using real-time PCR. In total, 116 HCV-RNA samples were genotyped, based on maximum likelihood phylogenetic analyses, using BioEdit, Modelgenerator, PHYML and FigTree software. The population consisted of 242,726 volunteers who donated blood from 2004-2006; the most common subgroup was males between the ages of 18-29 years old (37.30%). Within the whole group, 1,112 blood donors (0.46%) had indeterminate or positive serology; among these, 28.78% were males whose ages ranged from 18-29 years. A diagnosis of chronic HCV infection was confirmed for 304 donors (60.20% males; 66.45% were 30-49 years old), resulting in a prevalence of HCV RNA in 0.13% of the samples (304 of 242,726). HCV genotyping revealed a high frequency of genotype 1 (108/116) followed by genotype 3 (8/116). This study found HCV infection to be relatively infrequent in PA; genotype 1 was most commonly isolated. This information can help guide prevention and control policies aimed at efficient diagnosis and control measures.

Spotted fever group Rickettsia infecting ticks (Acari: Ixodidae) in the state of Santa Catarina, Brazil

During 2006-2008, a total of 260 adult ticks were collected from domestic and wild animals in different regions of the state of Santa Catarina (SC), Brazil, including areas where human cases of Brazilian spotted fever have been reported. Collected ticks belonging to nine species (Amblyomma aureolatum, Amblyomma cajennense, Amblyomma dubitatum, Amblyomma longirostre, Amblyomma ovale, Amblyomma tigrinum, Dermacentor nitens, Rhipicephalus microplus and Rhipicephalus sanguineus) were tested by polymerase chain reaction (PCR) for rickettsial infection. Overall, eight (3.1%) ticks were found to be infected with Rickettsia species. After sequencing the PCR products, we determined that the sequences generated from three A. aureolatum, one A. ovale and one R. sanguineus from the municipality of Blumenau, one A. ovale from the municipality of Águas Mornas and one A. ovale from the municipality of Urussanga were identical to the corresponding partial rickettsial ompA gene sequence of Rickettsia parkeri strain Atlantic rainforest. The sequence generated from one A. longirostre from Blumenau was 100% identical to the corresponding partial rickettsial ompA gene sequence of Rickettsia amblyommii strain AL. Because R. parkeri strain Atlantic rainforest was recently shown to have caused two cases of human spotted fever in other states of Brazil, the role of this rickettsial agent as a possible etiological agent of spotted fever in SC is discussed.