Seroepidemiological study of herpes simplex virus type 2 in patients with the acquired immunodeficiency syndrome in the city of Niterói, Rio de Janeiro, Brazil

This study was designed to determine the seroprevalence of herpes simplex virus type 2 (HSV-2) and to evaluate its association with age, sex as well as other demographic and behavioural factors in 150 human immunodeficiency virus (HIV) positive adults patients attending the general medical outpatient ward for routine care of Niterói, state of Rio de Janeiro, Brazil. Serum samples were screened for HSV-2 antibodies using an indirect ELISA. Eighty-three patients were men (mean age: 38.8) and 67 were women (mean age: 35.4). The estimated prevalence of HSV-2 was 52% (95% CI: 44-60%) and it was higher among men (53%) than among women (50.7%). Overall, the age of first sexual intercourse and past history of genital herpes were associated with HSV-2 seropositivity. Analysis by gender disclosed significant association of number of lifetime sex partners only among men. Although HSV-2 antibodies were frequent in the study group, genital herpes was reported by 21.8% of the HSV-2 positive subjects, indicating low awareness of the HSV-2 infection. These results may have public health importance for Brazil as the high rate of HSV-2 infection may act as a cofactor of HIV transmission.

Tegumentary leishmaniasis outbreak in Bella Vista City, Corrientes, Argentina during 2003

Bella Vista City, Corrientes, Argentina, reported an epidemic outbreak of tegumentary leishmaniasis during 2003. The mean age of the 31 cases was 25.0 ± 13.7 years old, with a sex ratio male:female 1.8, and without mucosal involvement. They clustered in two contiguous neighbourhoods, 96% in the periurban border and 4% in the peripheral outskirts. The transmission peak was estimated to have occurred during April 2003. Four species (3608 sand flies) were captured in nine sites: Lutzomyia neivai (90.1%), Lu. pessoai (8.9%), Lu. migonei (0.8 %), and Brumptomyia avellari (0.2 %). The outskirts/rural capture ratio of Lu. neivai was up to 3, and the outskirts/periurban up to 200. Therefore, the 'urban' transmission in this southernmost known focus is still an ecotone-border associated risk. The changes in human distribution or activities, patches of the secondary vegetation, periurban streams, rainfall of the previous year, and river period floods could all contribute to 'urban' outbreaks in the region. Tegumentary leishmaniasis risk should be assessed for any project that involves changes in land use throughout an endemic area.

Paleopathology of the commoners at Tell Amarna, Egypt, Akhenaten's capital city

The Egyptian Pharaoh Akhenaten initiated worship of a single god and established a new capital city (Tell Amarna) that was built and occupied only once from 1350-1330 BCE. This single short occupation offers a unique opportunity to study a short time period. The royal tombs have long been known and studied, but the location of graves for the common inhabitants has been an archaeological puzzle for more than 50 years. Recently four cemeteries have been located and the analysis of commingled bones from the South Tombs cemetery is presented here. The remains yield the following demographic profile: 53 adults with 19 females and 18 males; 14 juveniles between the ages of 5 and 17; and 3 infants. Arthritis and degenerative joint disease of the spine and joints indicates that DJD was not excessive. Only 2 to 8% of the adult population exhibits arthritis. There are 3 healed fractures of the arm (2 to 8% of the adult sample). There is 1 healed compressed fracture of the skull suggesting violence. The adult infection rate is between 2 and 8% with 3 healed and 1 active case of periostitis and no severe infections. Anemia is implicated by 23% of adult frontals exhibiting cribra orbitalia. Life for the common residents of Amarna appears to not have been as good as initially postulated.

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.

Molecular evidence that human immunodeficiency virus type 1 dissemination in a small Brazilian city was already taking place in the early 1990s

We recently performed a molecular epidemiology survey of human immunodeficiency virus type 1 (HIV-1) infection in Miracema, a small city in Southeast Brazil, and found multiple monophyletic clusters, consistent with independent introductions and spread of different viral lineages in the city. Here we apply Bayesian coalescent-based methods to the two largest subtype B clusters and estimate that the most recent common ancestors that gave rise to these two transmission chains were in circulation around 1991-1992. The finding that HIV-1 spread in this Brazilian small city was already taking place at a time Aids was considered a problem restricted to large urban centers may have important public health implications.

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.

Autochthonous horizontal transmission of a CRF02_AG strain revealed by a human immunodeficiency virus type 1 diversity survey in a small city in inner state of Rio de Janeiro, Southeast Brazil

As part of an ongoing study on the features of AIDS spread towards small cities and rural areas, we present a molecular survey of human immunodeficiency virus type 1 (HIV-1) polymerase sequences recovered between 2004 and 2006 from 71 patients receiving care in the city of Saquarema, inner state of Rio de Janeiro. Phylogenetic reconstructions found the two prevalent lineages in the state (subtypes B [59 strains, 83.1%], F1 [6 strains; 8.4%], and BF1 recombinants [four strains; 5.6%]), as well as two (2.8%) CRF02_AG strains, which seems to be an emerging lineage in the capital. These CRF02_AG sequences were recovered from a married heterosexual couple who never traveled abroad, thus providing the first molecular evidence of autochthonous horizontal transmission of this lineage of major global importance. Also, three phylogenetic clusters of strains recovered from a total of 18.3% of the cohort were uncovered. Their close genetic relatedness suggests they were recovered from patients who probably took part in the same chain of viral spread. In conjunction with our previous surveys from inner Rio de Janeiro, these results suggest that although small cities harbor unique molecular features of HIV-1 infection, they also clearly reflect and may rapidly absorb the diversity recorded in large urban centers.

Genetic structure of Aedes aegypti in the city of Córdoba (Argentina), a recently reinfested area

To understand the transmission of a vector-borne disease, knowledge of the magnitude of dispersal among vector populations is essential because of its influence on pathogen transfer. The principal vector of dengue, the most common arboviral disease in the world, is the mosquito Aedes aegypti (L.). This tropical and subtropical species is native to Africa but has dispersed worldwide since the XV century. In Argentina, the species was declared eradicated in 1963, but has reinfested the country in recent years. In the present work, we used RAPD-PCR markers to assess the levels of genetic variability and differentiation among populations of Ae. aegypti (the vector of dengue and yellow fever) in Córdoba, the second largest city in Argentina. We detected similar levels of genetic variability (He between 0.351-0.404) across samples and significant genetic differentiation between most population pairs within the city (F ST between 0.0013-0.0253). Genetic distances indicate that there are three distinct groups, formed predominantly by populations that are connected by, or near, main roads. This suggests that, in addition to other factors such as availability of oviposition sites or step-by-step migration, passive transport plays an important role in gene flow within the city.

First isolation of Cryptococcus gattii molecular type VGII and Cryptococcus neoformans molecular type VNI from environmental sources in the city of Belém, Pará, Brazil

Cryptococcus neoformans and Cryptococcus gattii are important agents of meningoencephalitis in humans in the city of Belém. This clinical data suggests that the region may be a highly endemic area for the pathogenic Cryptococcus species within the state of Pará (PA), Northern Brazil. Preliminary analysis of 11 environmental samples from the city of Belém showed two positive locations, including a hollow of a kassod tree (Senna siamea) colonized simultaneously by C. gattii molecular type VGII and C. neoformans molecular type VNI, and a birdcage in a commercial aviary positive for C. neoformans, molecular type VNI. This is the first evidence of an environmental occurrence of molecular types VNI and VGII in PA.

Malaria entomological inoculation rates in gold mining areas of Southern Venezuela

A longitudinal study of malaria vectors aiming to describe the intensity of transmission was carried out in five villages of Southern Venezuela between January 1999-April 2000. The man-biting, sporozoite and entomological inoculation rates (EIR) were calculated based on 121 all-night collections of anophelines landing on humans, CDC light traps and ultra violet up-draft traps. A total of 6,027 female mosquitoes representing seven species were collected. The most abundant species were Anopheles marajoara Galvão & Damasceno (56.7%) and Anopheles darlingi Root (33%), which together accounted for 89.7% of the total anophelines collected. The mean biting rate for An. marajoara was 1.27 (SD + 0.81); it was 0.74 (SD + 0.91) for An. darlingand 0.11 (SD + 0.10) for Anopheles neomaculipalpus Curry and the overall biting rate was 2.29 (SD + 1.06). A total of 5,886 mosquitoes collected by all three methods were assayed by ELISA and 28 pools, equivalent to 28 mosquitoes, yielded positive results for Plasmodium spp. CS protein. An. neomaculipalpus had the highest sporozoite rate 0.84% (3/356), followed by An. darlingi 0.82% (16/1,948) and An. marajoara 0.27% (9/3,332). The overall sporozoite rate was 0.48% (28/5,886). The rates of infection by Plasmodium species in mosquitoes were 0.37% (22/5,886) for Plasmodium vivax(Grassi & Feletti) and 0.10% (6/5,886) for Plasmodium falciparum (Welch). The estimated overall EIR for An. darling was 2.21 infective bites/person/year, 1.25 for An. marajoara and 0.34 for An. neomaculipalpus. The overall EIR was four infective bites/person/year. The biting rate, the sporozoite rate and the EIR are too low to be indicators of the efficacy of control campaigns in this area.

Seroepidemiological study of human parvovirus B19 among human immunodeficiency virus-infected patients in a medium-sized city in Rio de Janeiro, Brazil

Parvovirus B19 (B-19) may cause chronic anaemia in immunosuppressed patients, including those infected with human immunodeficiency virus (HIV). We studied single serum samples from 261 consecutive HIV-infected patients using an enzyme immunoassay to detect IgG antibodies to B-19. The seroprevalence of B-19-IgG was 62.8%. The differences in seroprevalence across gender, age, educational categories, year of collection of the serum samples, clinical and antiretroviral therapy characteristics, CD4+ count, CD4+ and CD8+ percentage and CD4+/CD8+ ratios were neither substantial nor statistically significant. There was a non-significant, inverse association between B-19 seropositivity and plasma HIV load and haemoglobin level. Our results indicated that 37.1% of patients might be susceptible to B-19 infection and remained at risk for being infected, mainly during epidemic periods. As B-19 infection can be treated with immune globulin preparations, it may be included in the diagnostic approach toward chronic anaemia in HIV-infected patients.

A study of multidrug-resistant tuberculosis in risk groups in the city of Santos, São Paulo, Brazil

Monitoring the extent of and trends in multidrug-resistant tuberculosis (MDR-TB) is a priority of the Brazilian National Tuberculosis Control Programme. The current study aimed to estimate the incidence of MDR-TB, describe the profile of TB drug resistance in risk groups and examine whether screening for MDR-TB adhered to the recommended guidelines. A descriptive study that examined diagnosed cases of pulmonary TB was conducted in the city of Santos, Brazil, between 2000-2004. Of the 2,176 pulmonary TB cases studied, 671 (30.8%) met the criteria for drug sensitivity testing and, of these cases, 31.7% (213/671) were tested. Among the tested cases, 9.4% were resistant to one anti-TB drug and 15% were MDR. MDR was observed in 11.6% of 86 new TB cases and 17.3% of 127 previously treated cases. The average annual incidence of MDR-TB was 1.9 per 100,000 inhabitants-years. The extent of known MDR-TB in the city of Santos is high, though likely to be underestimated. Our study therefore indicates an inadequate adherence to the guidelines for MDR-TB screening and suggests the necessity of alternative strategies of MDR-TB surveillance.

Lutzomyia longipalpis abundance in the city of Posadas, northeastern Argentina: variations at different spatial scales

The distribution of Lutzomyia longipalpis is heterogeneous with a pattern of high abundance areas (HAAs) embedded in a matrix of low abundance areas (LAAs). The objective of this study was to describe the variability in the abundance of Lu. longipalpis at two different spatial levels and to analyse the relationship between the abundance and multiple environmental variables. Of the environmental variables analysed in each household, the condition that best explained the differences in vector abundance between HAA-LAA was the variable "land_grass", with greater average values in the peridomestic environments within the LAA, and the variables "#sp tree", "#pots" and "dist_water" that were higher in the HAA. Of the environmental variables analysed in the patches, the variable "unpaved_streets" was higher in the LAAs and the variable "prop_inf_dogs" was higher in the HAAs. An understanding of the main environmental variables that influence the vector distribution could contribute to the development of strategies for the prevention and control of visceral leishmaniasis (VL). This is the first work in which environmental variables are analysed at the micro-scale in urban areas at the southern edge of the current range of Lu. longipalpis. Our results represent a significant contribution to the understanding of the abundance of the vector in the peridomestic habitats of the region.

Detection of enteric viruses in recreational waters of an urban lagoon in the city of Rio de Janeiro, Brazil

The aim of this study was to determine the occurrences of the group A rotavirus (RVA), norovirus (NoV) and human adenovirus (HAdV) in the surface waters of an urban lagoon (Rodrigo de Freitas Lagoon) in the city of Rio de Janeiro, Brazil. During one year of surveillance, water samples were obtained from the lagoon and other interconnected ecosystems (river and beach). The samples were concentrated using an adsorption-elution method with a negatively charged membrane and tested by qualitative and quantitative polymerase chain reaction assays. RVA was the most prevalent virus detected (24.3%) with a viral load ranging from 3.0 x 10¹-5.6 x 10(4) genome copies/L, followed by NoV (18.8%) and HAdV (16.7%). Considering water samples suitable for bathing, according to Escherichia coli criterion (< 2,000 most probable number/100 mL), viruses were detected in 50% (57/114) of them. Physicochemical parameters were also measured and showed possible correlations between turbidity and RVA presence and between pH and NoV presence. These data demonstrate the importance of considering viral parameters to ensure water quality and the utilisation of these parameters as additional tools for the characterisation of environmental contamination.

Molecular characterisation of hepatitis B virus in the resident Chinese population in Panama City

Despite the effectiveness of current hepatitis B virus (HBV) vaccines, it is estimated that 350 million individuals suffer from chronic HBV infection and more than 50% of these affected individuals live on the Asian continent. Panama is a country with a great diversity of foreign groups; the Chinese community is a large example of this phenomenon. There is an urgent need to perform studies that evaluate the prevalence and the genetic diversity of HBV in this community. This study aimed to evaluate the prevalence of HBV and its genotypes and mutant variants in the Chinese population residing in Panama. In total, 320 subjects were enrolled in the study. Forty-two subjects (13.1%) were positive for HBsAg and HBV-DNA from 18 subjects revealed the presence of genotypes B2 and C1. Secondary mutations associated with drug resistance at positions rtV207L and rtN239T of the reverse transcriptase gene were identified. Additionally, the mutation pair A1762T/G1764A was found in three samples and the mutation G1896A was detected in an HBeAg-negative subject. In conclusion, to our knowledge, this is the first study to report high HBV prevalence rates in resident ethnic Chinese in Central America and the presence of genotypes B2 and C1 in this region.