Prevalence of hepatitis B and C virus infection among leprosy patients in a leprosy-endemic region of central Brazil

Leprosy and hepatitis B virus (HBV) are highly endemic in some regions of the state of Mato Grosso, in central Brazil. The association of leprosy with HBV and hepatitis C virus (HCV) was assessed using a seroprevalence study and 191 leprosy outpatients were included. Demographic data and the clinical classification of leprosy were recorded. Evidence of previous HBV infection was present in 53 patients (27.7%, 95% confidence interval: 21.9-34.5) and two (1%) were HBsAg positive. Five (2.6%) had antibodies to HCV. The prevalence of previous exposure to HBV was higher than expected for an adult population in central Brazil. In contrast, the prevalence of anti-HCV antibodies was not much higher regarding the age range of participants. HBV markers were associated with a higher number of sex partners and the use of injections without proper sterilisation of the syringes. The number of HBV carriers was small, suggesting that there was no increased likelihood of chronification among these patients.

Hourly activity of Lutzomyia neivai in the endemic zone of cutaneous leishmaniasis in Tucumán, Argentina: preliminary results

In the present work, the hourly activity of Lutzomyia neivai was studied in the southern part of the province of Tucumán, Argentina, in an area of transmission of cutaneous leishmaniasis during two months of higher activity. In addition, the variables that influenced the abundance of Lu. neivai were evaluated. A total of 1,146 individuals belonging to Lu. neivai (97%) and Lutzomyia migonei (3%) were captured. The hourly activity of Lu. neivai was mainly nocturnal, with a bimodal pattern in both months. In January, the variable that most influenced the abundance of Lu. neivai was the temperature, whereas in April, that variable was humidity. These results may contribute to the design of anti-vectorial control measures at a micro-focal scale.

Lanfrediella amphicirrus gen. nov. sp. nov. Nematotaeniidae (Cestoda: Cyclophyllidea), a tapeworm parasite of Rhinella marina (Linnaeus, 1758) (Amphibia: Bufonidae)

The family Nematotaeniidae, tapeworms commonly found in the small intestines of amphibians and reptiles, includes 27 recognised species distributed among four genera: Bitegmen Jones, Cylindrotaenia Jewell, Distoichometra Dickey and Nematotaenia Lühe. The taxonomy of these cestodes is poorly defined, due in part to the difficulties of observing many anatomical traits. This study presents and describes a new genus and species of nematotaeniid parasite found in cane toads (Rhinella marina) from eastern Brazilian Amazonia. The cestodes were collected during the necropsy of 20 hosts captured in the urban area of Belém, Pará. The specimens were fixed and processed for light microscopy, scanning electron microscopy (SEM) and three-dimensional (3D) reconstruction. Samples were also collected for molecular analyses. The specimens presented a cylindrical body, two testes and paruterine organs. However, they could not be allocated to any of the four existing nematotaeniid genera due to the presence of two each of dorsal compact medullary testes, cirri, cirrus pouches, genital pores, ovaries and vitelline glands per mature segment. Lanfrediella amphicirrus gen. nov. sp. nov. is the first nematotaeniid studied using Historesin analysis, SEM and 3D reconstruction, and it is the second taxon for which molecular data have been deposited in GenBank.

Genotypes of Cryptococcus neoformans and Cryptococcus gattii as agents of endemic cryptococcosis in Teresina, Piauí (northeastern Brazil)

Throughout Brazil, Cryptococcus neoformans is the cause of cryptococcosis, whereas Cryptococcus gattii is endemic to the northern and northeastern states. In this study, the molecular types of 63 cryptococcal isolates recovered from the cerebrospinal fluid of meningitis patients diagnosed between 2008-2010 in Teresina, Piauí, Brazil, were analysed. Out of the 63 patients, 37 (58.7%) were human immunodeficiency virus (HIV)-positive and 26 (41.3%) were HIV-negative. URA5-restriction fragment length polymorphism analysis identified 37/63 (58.7%) isolates as the C. neoformans VNI genotype, predominantly in HIV-positive patients (32/37, 86.5%), and 24/63 (38.1%) as the C. gattii VGII genotype, mostly in HIV-negative patients (21/26, 80.8%). The occurrence of C. gattii VGII in six apparently healthy children and in seven adolescents/young adults in this region reaffirms the endemic occurrence of C. gattii VGII-induced primary cryptococcosis and early cryptococcal infection. Lethality occurred in 18/37 (48.6%) of the HIV-positive subjects and in 13/26 (50%) of the HIV-negative patients. Our results provide new information on the molecular epidemiology of C. neoformans and C. gattii in Brazilian endemic areas.

Molecular evidence for a single taxon, Anopheles nuneztovari s.l., from two endemic malaria regions in Colombia

To elucidate the Anopheles nuneztovari s.l. taxonomic status at a microgeographic level in four malaria endemic localities from Antioquia and Córdoba, Colombia, fragments of the cytochrome oxidase subunit I (COI) and the white gene were used. The COI analysis showed low genetic differentiation with fixation index (F ST) levels between -0.02-0.137 and Nm values between 3-∞, indicating the presence of high gene flow among An. nuneztovari s.l. populations from the four localities. The COI network showed a single most common haplotype, type 1 (n = 55), present in all localities, as the likely ancestral haplotype. Analysis of the white gene showed that An. nuneztovari s.l. populations from both departments grouped with haplotypes 19 and 20, which are part of lineage 3 reported previously. The results of the present study suggest that An. nuneztovari s.l. is a single taxon in the area of the present study.

Distribution of phlebotomine fauna (Diptera: Psychodidae) across an urban-rural gradient in an area of endemic visceral leishmaniasis in northern Brazil

The number of visceral leishmaniasis (VL) cases has increased over the past 10 years in Brazil, especially in the North and Northeast regions of the country. The aim of this study was to evaluate the urbanisation of VL vectors in Barcarena, Pará, an area in northern Brazil where VL is endemic. Sandflies were captured using Centers for Disease Control (CDC) light traps along an urban-rural gradient. The CDC traps were installed inside hen houses at a height of 150 cm. A total of 5,089 sandflies were collected and 11 species were identified. The predominant species was Lutzomyia longipalpis (rate of 95.15%), which suggests its participation in the transmission of VL. A total of 1,451 Lu. longipalpis females were dissected and no Leishmania infections were detected. Most of the sandflies were captured at the border of a forest (88.25%) and no flies were captured in the urban area, which suggests that transmission is still restricted to rural sites. However, the fact that a specimen was collected in an intermediate area indicates that urbanisation is a real possibility and that vector monitoring is important.

Report of Lutzomyia longipalpis (Lutz & Neiva, 1912) (Diptera: Psychodidae: Phlebotominae) in a cutaneous-leishmaniasis-endemic area of Panama

Lutzomyia longipalpis is the primary vector of the parasite responsible for visceral leishmaniasis in the Americas. In the present study, Lu. longipalpis was found in a domiciliary area in Limón, a district in Capira, a region in which cutaneous leishmaniasis is endemic in Panama. Previously, this species has been found in a humid forest in this same region. Finding Lu. longipalpis in domiciliary areas indicates that this species may be adapting to new habitats and that it may play a role in the transmission of leishmaniasis in Panama.

Antibodies against the Plasmodium falciparum glutamate-rich protein from naturally exposed individuals living in a Brazilian malaria-endemic area can inhibit in vitro parasite growth

The glutamate-rich protein (GLURP) is an exoantigen expressed in all stages of the Plasmodium falciparum life cycle in humans. Anti-GLURP antibodies can inhibit parasite growth in the presence of monocytes via antibody-dependent cellular inhibition (ADCI), and a major parasite-inhibitory region has been found in the N-terminal R0 region of the protein. Herein, we describe the antiplasmodial activity of anti-GLURP antibodies present in the sera from individuals naturally exposed to malaria in a Brazilian malaria-endemic area. The anti-R0 antibodies showed a potent inhibitory effect on the growth of P. falciparum in vitro, both in the presence (ADCI) and absence (GI) of monocytes. The inhibitory effect on parasite growth was comparable to the effect of IgGs purified from pooled sera from hyperimmune African individuals. Interestingly, in the ADCI test, higher levels of tumour necrosis factor alpha (TNF-α) were observed in the supernatant from cultures with higher parasitemias. Our data suggest that the antibody response induced by GLURP-R0 in naturally exposed individuals may have an important role in controlling parasitemia because these antibodies are able to inhibit the in vitro growth of P. falciparum with or without the cooperation from monocytes. Our results also indicate that TNF-α may not be relevant for the inhibitory effect on P. falciparum in vitro growth.

Change in mutation patterns of Plasmodium vivax dihydrofolate reductase (Pvdhfr) and dihydropteroate synthase (Pvdhps) in P. vivax isolates from malaria endemic areas of Thailand

Malaria is the most important public health problem in several countries. In Thailand, co-infections of Plasmodium vivax and Plasmodium falciparum are common. We examined the prevalence and patterns of mutations in P. vivax dihydrofolate reductase (Pvdhfr) and P. vivax dihydropteroate synthase (Pvdhps) in 103 blood samples collected from patients with P. vivax infection who had attended the malaria clinic in Mae Sot, Tak Province during 2009 and 2010. Using nested polymerase chain reaction-restriction fragment length polymorfism, we examined single nucleotide polymorphisms-haplotypes at amino acid positions 13, 33, 57, 58, 61, 117 and 173 of Pvdhfr and 383 and 553 of Pvdhps. All parasite isolates carried mutant Pvdhfr alleles, of which the most common alleles were triple mutants (99%). Eight different types of Pvdhfr and combination alleles were found, as follows: 57I/58R/117T, 57I/58R/117T, 57I/58R/117T/N, 57L/58R/117T, 57L/58R/117T, 58R/61M/117N, 58R/61M/117N and 13L/57L/58R/117T. The most common Pvdhfr alleles were 57I/58R/117T (77.7%), 57I/58R/117T/N (1%), 57L/58R/117T (5.8%) and 58R/61M/117N (14.5%). The most common Pvdhfr alleles were 57I/58R/117T (77.7%), 57I/58R/117T/N (1%), 57L/58R/117T (5.8%) and 58R/61M/117N (14.5%). Additionally, we recovered one isolate of a carrying a quadruple mutant allele, 13L/57L/58R/117T. The most prevalent Pvdhps allele was a single mutation in amino acid 383 (82.5%), followed by the wild-type A383/A553 (17.5%) allele. Results suggest that all P. vivax isolates in Thailand carry some combination of mutations in Pvdhfr and Pvdhps. Our findings demonstrate that development of new antifolate drugs effective against sulfadoxine-pyrimethamine-resistant P. vivax is required.

Habitat suitability of Anopheles vector species and association with human malaria in the Atlantic Forest in south-eastern Brazil

Every year, autochthonous cases of Plasmodium vivax malaria occur in low-endemicity areas of Vale do Ribeira in the south-eastern part of the Atlantic Forest, state of São Paulo, where Anopheles cruzii and Anopheles bellator are considered the primary vectors. However, other species in the subgenus Nyssorhynchus of Anopheles (e.g., Anopheles marajoara) are abundant and may participate in the dynamics of malarial transmission in that region. The objectives of the present study were to assess the spatial distribution of An. cruzii, An. bellator and An. marajoara and to associate the presence of these species with malaria cases in the municipalities of the Vale do Ribeira. Potential habitat suitability modelling was applied to determine both the spatial distribution of An. cruzii, An. bellator and An. marajoara and to establish the density of each species. Poisson regression was utilized to associate malaria cases with estimated vector densities. As a result, An. cruzii was correlated with the forested slopes of the Serra do Mar, An. bellator with the coastal plain and An. marajoara with the deforested areas. Moreover, both An. marajoara and An. cruzii were positively associated with malaria cases. Considering that An. marajoara was demonstrated to be a primary vector of human Plasmodium in the rural areas of the state of Amapá, more attention should be given to the species in the deforested areas of the Atlantic Forest, where it might be a secondary vector.

Echinococcus granulosus genotypes circulating in alpacas (Lama pacos) and pigs (Sus scrofa) from an endemic region in Peru

The identification of the genotypes of Echinococcus granulosus present in livestock and wild animals within regions endemic for cystic echinococcosis (CE) is epidemiologically important. Individual strains display different biological characteristics that contribute to outbreaks of CE and that must be taken into account in the design of intervention programs. In this study, samples of hydatid cysts due to E. granulosus were collected from alpacas (4) in Puno and pigs (8) in Ayacucho in Peru, an endemic region for CE. Polymerase chain reaction amplification and DNA sequencing of specific regions of the mitochondrial cytochrome C oxidase subunit 1 and NADH dehydrogenase subunit 1 genes confirmed the presence of a strain common to sheep, the G1 genotype, in alpacas. Two different strains of E. granulosus were identified in pigs: the G1 and the G7 genotypes. This is the first report of the G1 genotype of E. granulosus in alpacas in endemic regions of CE in Peru.

Biotic factors and occurrence of Lutzomyia longipalpis in endemic area of visceral leishmaniasis, Mato Grosso do Sul, Brazil

The relationships between environmental exposure to risk agents and health conditions have been studied with the aid of remote sensing imagery, a tool particularly useful in the study of vegetation cover. This study aims to evaluate the influence of environmental variables on the spatial distribution of the abundance of Lutzomyia longipalpis and the reported canine and human visceral leishmaniasis (VL) cases at an urban area of Campo Grande, state of Mato Grosso do Sul. The sandfly captures were performed in 13 residences that were selected by raffle considering four residences or collection station for buffer. These buffers were generated from the central house with about 50, 100 and 200 m from it in an endemic area of VL. The abundance of sandflies and human and canine cases were georreferenced using the GIS software PCI Geomatica. The normalized difference vegetation index (NDVI) and percentage of land covered by vegetation were the environmental variables extracted from a remote sensing IKONOS-2 image. The average NDVI was considered as the complexity of habitat and the standard deviation as the heterogeneity of habitat. One thousand three hundred sixty-seven specimens were collected during the catch. We found a significant positive linear correlation between the abundance of sandflies and the percentage of vegetation cover and average NDVI. However, there was no significant association between habitat heterogeneity and the abundance of these flies.

Molecular characterisation of Bartonella species in cats from São Luís, state of Maranhão, north-eastern Brazil

Bartonella species are fastidious bacteria that predominantly infect mammalian erythrocytes and endothelial cells and cause long-lasting bacteraemia in their reservoir hosts. Reports that describe the epidemiology of bartonellosis in Brazil are limited. This study aimed to detect and characterise Bartonella spp DNA from cat blood samples in São Luís, Maranhão, north-eastern Brazil. Among 200 cats tested for multiple genes, nine (4.5%) were positive for Bartonella spp: six cats for Bartonella henselae and three for Bartonella clarridgeiae. Based on the phylogenetic analysis of four genes, the B. henselae strain matched strains previously observed in Brazil and was positioned in the same clade as B. henselae isolates from the United States of America. Moreover, sequence alignment demonstrated that the B. clarridgeiae strain detected in the present study was the same as the one recently detected in cats from southern Brazil.

The combination of three faecal parasitological methods to improve the diagnosis of schistosomiasis mansoni in a low endemic setting in the state of Ceará, Brazil

Laboratory diagnosis of intestinal schistosomiasis mansoni can be accomplished through various methods of stool examination to detect parasites, ranging from the most classic tests (Kato-Katz) to several methods that are still undergoing validation. This study was conducted to assess two new parasite identification methods for diagnosing schistosomiasis mansoni in residents of a low endemic area in the municipality of Maranguape, in the state of Ceará, Brazil using the Kato-Katz method as a reference and serology (enzyme-linked immunosorbent assay) for the screening of patients. The Kato-Katz, the saline gradient method and the Helmintex® method parasite identification methods were employed only in subjects who exhibited positive serologic tests. The test results were then analysed and treatment of positive individuals was subsequently performed. After comparing the test results, we observed that the saline gradient method and the Helmintex® method were more effective in diagnosing schistosomiasis mansoni in the study area compared with the Kato-Katz method.

Seroreactivity to new Mycobacterium leprae protein antigens in different leprosy-endemic regions in Brazil

New Mycobacterium leprae protein antigens can contribute to improved serologic tests for leprosy diagnosis/classification and multidrug therapy (MDT) monitoring. This study describes seroreactivity to M. leprae proteins among participants from three highly endemic leprosy areas in Brazil: central-western Goiânia/Goiás (GO) (n = 225), Rondonópolis/Mato Grosso (MT) (n = 764) and northern Prata Village/Pará (PA) (n = 93). ELISA was performed to detect IgG to proteins (92f, 46f, leprosy IDRI diagnostic-1, ML0405, ML1213) and IgM to phenolic glycolipid-I (PGL-I). Multibacillary (MB) leprosy had positive rates for PGL-I that were similar to those for proteins; however, some anti-PGL-I-negative subjects were positive for proteins, suggesting that adding protein antigen to PGL-I can enhance the sensitivity of MB leprosy detection. In MT, different degrees of seroreactivity were observed and ranked for MB, former patients after MDT, paucibacillary (PB) leprosy, household contact (HHC) and endemic control (EC) groups. The seroreactivity of PB patients was low in GO and MT. HHCs from different endemic sites had similar IgG antibody responses to proteins. 46f and 92f were not recognised by most tuberculosis patients, ECs or HHCs within GO, an area with high BCG vaccination coverage. Low positivity in EC and HHC was observed in PA and MT. Our results provide evidence for the development of an improved serologic test that could be widely applicable for MB leprosy testing in Brazil.