Hepatitis B and C virus infection among Brazilian Amazon riparians

INTRODUCTION: Viral hepatitis is a major public health concern in Brazil. There are few past studies on this issue, especially among riparian communities. This study aims at determining the seroprevalence of viral hepatitis B and C in the riparian community of Pacuí Island, within the Cametá municipality of Pará State, Brazil. Moreover, this study aims to investigate the principal risk factors that this community is exposed to. METHODS: The current study has accessed blood samples from 181 volunteers who have answered an epidemiological questionnaire. Analyses on serological markers have been tested with commercial ELISA kits for detecting HBsAg, total anti-HBc, anti-HBs, and anti-HCV. Within seroreactive patients for HCV, RT-PCR and line probe assay have been performed to identify the viral genotype. RESULTS: In the serological marker analysis for hepatitis B, no reactivity for HBsAg, rate of 1.1% for total anti-HBc, and rate of 19.3% for anti-HBs have been observed. On hepatitis C, 8.8% seroprevalence has been found, in which 62.5% have gotten viral RNA. Among the risk factors studied, the following have been highlighted: non-use of condoms, sharing of cutting instruments, use of illicit drugs, and reports of family disease with HBV or HCV. CONCLUSIONS: The vaccination coverage against HBV is low, and the high prevalence of HCV within this community has been observed.

Antimicrobial Resistance of Shigella spp. isolated in the State of Pará, Brazil

INTRODUCTION: Shigella spp. are Gram-negative, nonsporulating, rod-shaped bacteria that belong to the family Enterobacteriaceae and are responsible for shigellosis or bacillary dysentery, an important cause of worldwide morbidity and mortality. METHODS: We studied the antibiotic resistance profiles of 122 Shigella spp. strains (81 S. flexneri, 41 S. sonnei, 1 S. boydii) isolated from patients (female and male from 0 to 80 years of age) presenting diarrhea in different districts of the State of Pará, in the North of Brazil. The antibiotic resistance of the strains, isolated from human fecal samples, was determined by the diffusion disk method and by using the VITEK-2 system. RESULTS: The highest resistance rate found was the resistance rate to tetracycline (93.8%), followed by the resistance rate to chloramphenicol (63.9%) and to trimethoprim/sulfamethoxazole (63.1%). Resistance to at least three drugs was more common among S. flexneri than S. sonnei (39.5% vs. 10%). Six (4.9%) strains were susceptible to all the antibiotics tested. All strains were susceptible to cefotaxime, ceftazidime, ciprofloxacin, nalidixic acid and nitrofurantoin. CONCLUSIONS: High rates of multidrug resistance in Shigella spp. are a serious public health concern in Brazil. It is extremely important to continuously monitor the antimicrobial resistances of Shigella spp. for effective therapy and control measures against shigellosis.

Molecular characterization of rabies virus isolated from non-haematophagous bats in Brazil

INTRODUCTION: Rabies is an important zoonosis that causes thousands of deaths worldwide each year. Although the terrestrial cycle, mainly transmitted by dogs, is controlled in Brazil, the aerial cycle remains a serious public health issue, besides the economic problem. In the aerial cycle, the haematophagous bat Desmodus rotundus is the main source of infection, where several different species of non-haematophagous bats can be infected and can transmit the virus. METHODS: The aim of this work was to study the epidemiological pattern of rabies using antigenic characterization with monoclonal antibodies and genetic characterization by reverse-transcriptase polymerase chain reaction followed by sequencing and phylogenetic analysis of non-haematophagous bats' and herbivorous animals' central nervous system samples from the western region of the State of São Paulo, Brazil. RESULTS: From 27 samples, 3 antigenic variants were identified: AgV-3, AgV-4, and AgV-6; and from 29 samples, 5 different clusters were identified, all belonging to the rabies virus species. CONCLUSIONS: Although only non-haematophagous bats were evaluated in the studied region, the majority of samples were from antigenic and genetic variants related to haematophagous bats Desmodus rotundus. Samples from the same antigenic variant were segregated in more than one genetic cluster. This study demonstrated the diversity of rabies virus genetic lineages presented and circulating in non-haematophagous bats in the studied region.

Acute meningoencephalomyelitis due to varicella-zoster virus in an AIDS patient: report of a case and review of the literature

Varicella-zoster virus (VZV) meningoencephalomyelitis is a rare but severe neurological complication of VZV reactivation in immunocompromised patients. We report the case of an HIV-infected individual who developed an acute and severe meningoencephalomyelitis accompanied by a disseminated cutaneous eruption due to VZV. The presence of VZV DNA in cerebrospinal fluid was confirmed by polymerase chain reaction (PCR) technique. The patient started undergoing an intravenous acyclovir therapy with a mild recovery of neurological manifestations. Varicella-zoster virus should be included as a cause of acute meningoencephalomyelitis in patients with AIDS. Early diagnosis followed by specific therapy should modify the rapid and fulminant course for this kind of patients.

Being ahead of its time the consumer resistance phenomenon: A comparative case study research

Double Degree.

Molecular characterization of the hepatitis B virus in autochthonous and endogenous populations in the Western Brazilian Amazon

INTRODUCTION: Hepatitis B virus (HBV) infection is a serious public health issue worldwide. Hepatitis B virus is classified into eight genotypes, varying from A to H, with distinct geographical distributions. In Brazil, the most frequent genotypes are A, D, and F. METHODS: This study aimed to characterize the HBV genotypes in cases of hepatitis B virus and hepatitis D virus (HDV) co-infections in an endemic area in the Western Brazilian Amazon. We analyzed 86 serum samples reactive for HBsAg from indigenous and non-indigenous populations obtained from previous serological surveys. RESULTS: Of the 86 reactive serum samples, 39 were found to be HBV-DNA-positive by semi-nested PCR. The genotypes were established by sequencing the amplified S gene region. We obtained 20 sequences classified into three genotypes: A, D, and F. Genotype A was the most frequent (60%), followed by D (35%) and F (5%). CONCLUSIONS: The distribution of the HBV genotypes reflected the pattern of historical occupation of the region.

Prevalence of hepatitis B virus infection and carriage after nineteen years of vaccination program in the Western Brazilian Amazon

INTRODUCTION: Reductions in the prevalence of hepatitis B virus (HBV) infection and carriage, decreases in liver cancer incidence, and changes in patterns of liver dysfunctions are described after hepatitis B vaccination. METHODS: We conducted a population-based seroprevalence study aimed at estimating the HBV prevalence and risk of infection in the rural area of Lábrea following nineteen years of HBV vaccination. RESULTS: Half of the subjects showed total anti-HBc of 52.1% (95% CI 49.6-54.7). The HBsAg prevalence was 6.2% (95% CI 5.1-7.6). Multivariate analysis showed an inverse association between HBV infection and vaccination (OR 0.62; 95% CI 0.44-0.87). HBsAg remained independently associated with past hepatitis (OR 2.44; 95% CI 1.52-3.89) and inversely to vaccination (OR 0.43; 95% CI 0.27-0.69). The prevalence of HBeAg among HBsAg-positive individuals was 20.4% (95% CI 12.8-30.1), with the positive subjects having a median age of 11 years (1-46) p=0.0003. CONCLUSIONS: We demonstrate that HBV infection is still an important public health issue and that HBV vaccination could have had better impact on HBV epidemiology. If we extrapolate these findings to other rural areas in the Brazilian Amazon, we can predict that the sources of chronic infected patients remain a challenge. Future studies are needed regarding clinical aspects, molecular epidemiology, surveillance of acute cases, and risk groups.

Drug resistance of Mycobacterium tuberculosis strains in southern Brazil

INTRODUCTION: The aim of this work was to evaluate the prevalence of Mycobacterium tuberculosis (MT) strains with mutations that could result in resistance to the main drugs used in treatment in a region with one of the highest numbers of tuberculosis (TB) cases in southern Brazil. METHODS: Deoxyribonucleic acid (DNA) from 120 sputum samples from different patients suspicious of pulmonary tuberculosis who attended the Municipal Public Laboratory for Mycobacterium sp. diagnosis was directly amplified and analyzed by PCR-SSCP. The DNA was amplified in known hotspot mutation regions of the genes rpoB, ahpC, embB, katG, inhA, and pncA. RESULTS: The percentage of samples positive by culture was 9.2% (11/120); 5% (6/120) were positive by bacilloscopy and MT-PCR, and DNA fragments of the aforementioned resistance genes could be amplified from seven (7) of the eleven (11) samples with positive results, either by culture or PCR/bacilloscopy. All presented a SSCP pattern similar to a native, nonresistant genotype, with the ATCC strain 25177 as control, except for one sample (0.01%), which presented a SSCP profile demonstrating mutation at the embB gene. CONCLUSIONS: These results are consistent with the empirical observations by physicians treating TB patients in our region of a low occurrence of cases that are refractory to conventional treatment schemes, in contrast to other parts of the country. Continued surveillance, especially molecular, is essential to detect and monitor the outbreak of MT-resistant strains.

Chikungunya virus infection: report of the first case diagnosed in Rio de Janeiro, Brazil

Initially diagnosed in Africa and Asia, the Chikungunya virus has been detected in the last three years in the Caribbean, Italy, France, and the United States of America. Herein, we report the first case for Rio de Janeiro, Brazil, in 2010.

Circulation of the rabies virus in non-hematophagous bats in the city of Rio de Janeiro, Brazil, during 2001-2010

INTRODUCTION: Rabies is one of the most known lethal zoonosis, responsible for 55,000 human deaths per year. It is transmitted to humans mainly by the bite of domestic or wild animals infected with the virus. This paper shows the circulation of this virus in non-hematophagous bats in the City of Rio de Janeiro, Brazil. METHODS: A survey was performed on the number of bats that had been sent for diagnosis by the Seção de Virologia of the Instituto Municipal de Medicina Veterinária Jorge Vaitsman and were positive for rabies. The positive animals were identified, and the isolated viruses were sent for antigenic typification with indirect immunofluorescence. The results were compared with the antigenic panel of the Centers for Disease Control and Prevention. RESULTS: During 2001-2010, the laboratory received 555 non-hematophagous bats for rabies diagnosis, with 198 (35.7%) from Rio de Janeiro City. A total of 11 (5.5%) animals were positive for this disease. Antigenic typification revealed the predominance of variant 3 in 9 (81.8%) of the isolated viruses; 1 virus was classified as variant 4 and 1 variant was identified that segregated with the viruses in insectivorous bats. CONCLUSIONS: The data obtained in this study showed the presence of the rabies virus in synanthropic populations of non-hematophagous bats in the City of Rio de Janeiro. The circulation of this agent in these animals represents a serious risk to human and animal health and requires attention and control measures by the authorities.

Cat infected by a variant of bat rabies virus in a 29-year disease-free urban area of southern Brazil

INTRODUCTION: After 29 years, rabies was detected in a cat in Curitiba, southern Brazil. METHODS: The fluorescent antibody test (FAT) and mouse inoculation test (MIT) were performed on central nervous system (CNS) samples. RESULTS: Direct immunofluorescence was negative, but the biological test was positive and rabies virus was characterized as variant 4 (from Tadarida brasiliensis). CONCLUSIONS: Reappearance of rabies in domestic animals warns of sylvatic-aerial risk of infection and the necessity of monitoring bats in historically rabies-free areas.

Genetic diversity of dengue virus serotypes 1 and 2 in the State of Paraná, Brazil, based on a fragment of the capsid/premembrane junction region

INTRODUCTION: The precise identification of the genetic variants of the dengue virus is important to understand its dispersion and virulence patterns and to identify the strains responsible for epidemic outbreaks. This study investigated the genetic variants of the capsid-premembrane junction region fragment in the dengue virus serotypes 1 and 2 (DENV1-2). METHODS: Samples from 11 municipalities in the State of Paraná, Brazil, were provided by the Central Laboratory of Paraná. They were isolated from the cell culture line C6/36 (Aedes albopictus) and were positive for indirect immunofluorescence. Ribonucleic acid (RNA) extracted from these samples was submitted to the reverse transcription polymerase chain reaction (RT-PCR) and nested PCR. RESULTS: RT-PCR revealed that 4 of the samples were co-infected with both serotypes. The isolated DENV-1 sequences were 95-100% similar to the sequences of other serotype 1 strains deposited in GenBank. Similarly, the isolated DENV-2 sequences were 98-100% similar to other serotype 2 sequences in GenBank. According to our neighbor-joining tree, all strains obtained in this study belonged to genotype V of DENV-1. The DENV-2 strains, by contrast, belonged to the American/Asian genotypes. CONCLUSIONS: The monitoring of circulating strains is an important tool to detect the migration of virus subtypes involved in dengue epidemics.

Hepatitis B virus infection in children, adolescents, and their relatives: genotype distribution and precore and core gene mutations

INTRODUCTION:The objectives of this study were evaluate hepatitis B virus (HBV) serological markers in children and adolescents followed up at the Child Institute of the Hospital das Clínicas, Faculdade de Medicina de São Paulo, Universidade de São Paulo; identify chronic HBV carriers and susceptible individuals in the intrafamilial environment; characterize HBV genotypes; and identify mutations in the patients and household contacts. METHODS: Ninety-five hepatitis B surface antigen-positive children aged <19 years and 118 household contacts were enrolled in this study. Commercial kits were used for the detection of serological markers, and PCR was used for genotyping. RESULTS: Hepatitis B e antigen (HBeAg) was detected in 66.3% (63/95) of cases. Three of the 30 HBeAg-negative and anti-HBeAg-positive patients presented with precore mutations and 11 presented with mutations in the basal core promoter (BCP). Genotype A was identified in 39 (43.8%) patients, genotype D in 45 (50.6%), and genotype C in 5 (5.6%). Of the 118 relatives, 40 were chronic HBV carriers, 52 presented with the anti-HBc marker, 19 were vaccinated, and 7 were susceptible. Among the relatives, genotypes A, D, and C were the most frequent. One parent presented with a precore mutation and 4 presented with BCP mutations. CONCLUSIONS: Genotypes A and D were the most frequent among children, adolescents, and their relatives. The high prevalence of HBV in the families showed the possibility of its intrafamilial transmission.