ABSTRACT Scorpion envenoming is considered a public health problem in Brazil. A recent study described a variation in the clinical outcome of envenoming by Tityus obscurus in two populations separated by 850 km in the northeastern Amazon region. Our aim was to evaluate whether such clinical and toxinological variations are associated with underlying differences in genetic diversity between these two T. obscurus populations. We obtained DNA from five individuals of each population, in the municipalities of Belém and Santarém, located east and west of the state of Pará, Brazil, respectively. Gene regions encoding mitochondrial DNA (mtDNA) markers cytochrome oxidase subunit I (COI) and ribosomal 16S RNA (16S) were amplified and sequenced. Phylogenetic analyses were performed using maximum likelihood (ML) and Bayesian inferences (BA) for both molecular data (COI and 16S). The sampled T. obscurus populations corresponded to two distinct mtDNA lineages (genetic distance COI K2 P = 0.08 to 0.13; 16S K2 P = 0.10 to 0.11) with no shared mutations between groups and well supported by ML and BA inferences. Based on the divergence values found between eastern and western populations (COI, 0.07 to 0.12; 16S, 0.10), our study confirms the genetic heterogeneity of T. obscurus populations within the state of Pará, which correlates with observed venom and clinical differences, and reinforces the need for mapping the distribution of haplotypes throughout the geographic range of T. obscurus, to aid in future epidemiological, toxinological, and evolutionary studies.

RESUMO O envenenamento por escorpiões é considerado um problema de saúde pública no Brasil. Um estudo recente descreve a variação do quadro clínico de envenenamento por Tityus obscurus em duas populações separadas por uma distância de 850 km no nordeste da Amazônia. O objetivo deste estudo foi avaliar se tais variações clínicas e toxicológicas estão associadas a diferenças subjacentes na diversidade genética entre essas duas populações de T. obscurus. Obtivemos DNA de cinco indivíduos de cada população nos municípios de Belém e Santarém, localizados a leste e oeste do estado do Pará, Brasil, respectivamente. Regiões gênicas que codificam marcadores de DNA mitocondrial (mtDNA) citocromo oxidase subunidade I (COI) e RNA ribossômico 16S (16S) foram amplificadas e sequenciadas. As análises filogenéticas foram realizadas por máxima verossimilhança (ML) e inferência Bayesiana (BA) para ambos os dados moleculares (COI e 16S). As populações de T. obscurus amostradas corresponderam a duas linhagens distintas de mtDNA (distância genética COI K2 P = 0,08 a 0,13; 16S K2 P = 0,10 a 0,11) sem mutações compartilhadas entre os grupos, e bem corroboradas por inferências ML e BA. Com base nos valores de divergência encontrados entre as populações oriental e ocidental (COI, 0,07 a 0,12; 16S, 0,10), nosso estudo confirma a heterogeneidade genética das populações de T. obscurus no estado do Pará. Os resultados são congruentes com as diferenças observadas no quadro clínico dos acidentes e toxicidade do veneno, e reforçam a necessidade de mapear a distribuição de haplótipos em toda a distribuição geográfica de T. obscurus, para auxiliar em futuros estudos epidemiológicos, toxinológicos e evolutivos.

Abstract INTRODUCTION: In the Belém Metropolitan Region (BMR), Pará State, Brazil, American cutaneous leishmaniasis (ACL) is endemic; however, very little is known regarding its causative agents. Therefore, we used our standard diagnostic approach combined with an RNA polymerase II largest subunit (RNAPOIILS)-polymerase chain reaction (PCR) followed by analysis of restriction fragment length polymorphism (PCR-RFLP) to identify Leishmania spp. ACL agents in this region. METHODS: Thirty-two Leishmania spp. isolates from patients with ACL in the BMR during 1995-2018 were analyzed. Leishmania spp. DNA samples were amplified using the primers RPOR2/RPOF2, and the 615-bp PCR products were subjected to enzymatic digestion using TspRI and HgaI endonucleases. RESULTS: ACL etiological agents in the BMR comprised Leishmania (Viannia) lindenbergi (43.7%) followed by Leishmania (Viannia) lainsoni (34.4%), Leishmania (Leishmania) amazonensis (12.5%), and Leishmania (Viannia) braziliensis (9.4%). CONCLUSIONS: To our knowledge, the results of the study revealed for the first time that L. (V.) lindenbergi and L. (V.) lainsoni are the main ACL agents in BMR.

Resumo Objetivo O objetivo deste estudo foi avaliar a prevalência global e tipo-específica da infecção pelo papilomavírus humano (HPV) entre mulheres que vivem em comunidades ribeirinhas do estado do Pará, Amazônia oriental, Brasil. Estas comunidades são habitadas por pessoas de baixa renda, e são acessíveis somente por meio de pequenos barcos. A citologia cervical e os fatores de risco para a infecção por HPV também foram avaliados. Métodos Amostras cervicais de 353 mulheres de comunidades selecionadas foram coletadas para a análise citológica e para a detecção do HPV. A prevalência global e tipoespecífica dos HPV-16 e HPV-18, principais tipos oncogênicos no mundo, foram avaliadas por meio de reação em cadeia de polimerase (PCR) convencional e PCR em tempo real. Os fatores de risco para a infecção por HPV foram avaliados a partir de questionários epidemiológicos. Resultados A idade média das participantes foi de 37 anos (desvio padrão [DP] ± 13,7). A maioria era casada ou tinha um parceiro sexual fixo (79%) e baixo nível de escolaridade (80%) e de renda familiar mensal (< U$ 250; 53%). A prevalência global do HPV foi de 16,4% (n = 58), com 8 casos de HPV-16 (2,3%) e 5 casos de HPV-18 (1,4%). Aproximadamente 70% das mulheres entrevistadas nunca tinha realizado o exame preventivo de Papanicolau. Os resultados citológicos anormais foram encontrados em 27,5% (n = 97) das amostras, com taxas mais altas da infecção por HPV de acordo com a severidade das lesões (p = 0,026). Conclusões As infecções por HPV-16 e HPV-18 não foram predominantes em nosso estudo, apesar da alta prevalência global da infecção por HPV. No entanto, o potencial oncogênico desses tipos e a baixa cobertura do exame de Papanicolau entre mulheres de comunidades ribeirinhas demonstram um risco potencial para o desenvolvimento de lesões cervicais e sua progressão para o câncer de colo do útero, uma vez que o acesso a essas comunidades é difícil e, na maioria dos casos, estas mulheres não têm acesso aos serviços de atenção primária e de saúde pública.

Abstract Purpose The aim of this study was to evaluate the overall and type-specific prevalence of human papillomavirus (HPV) infection among females living in riverside communities in the state of Pará, in the Eastern Brazilian Amazon. These communities are inhabited by low-income people, and are accessible only by small boats. Cervical cytology and risk factors for HPV infection were also assessed. Methods Cervical samples from 353 women of selected communities were collected both for Papanicolau (Pap) test and HPV detection. Conventional polymerase chain reaction (PCR) and real-time PCR were used to assess the overall and type-specific prevalence of HPV-16 and HPV-18, the main oncogenic types worldwide. Epidemiological questionnaires were used for the assessment of the risk factors for HPV infection. Results The mean age of the participants was 37 years (standard deviation [SD] ± 13.7). Most were married or with a fixed sexual partner (79%), and had a low educational level (80%) and family monthly income (< U$ 250; 53%). Overall, HPV prevalence was 16.4% (n = 58), with 8 cases of HPV-16 (2.3%) and 5 of HPV-18 (1.4%). Almost 70% of the women surveyed had never undergone the Pap test. Abnormal cytology results were found in 27.5% (n = 97) of the samples, with higher rates of HPV infection according to the severity of the lesions (p = 0.026). Conclusions The infections by HPV-16 and HPV-18 were not predominant in our study, despite the high prevalence of overall HPV infection. Nevertheless, the oncogenic potential of these types and the low coverage of the Pap test among women from riverside communities demonstrate a potential risk for the development of cervical lesions and their progression to cervical cancer, since the access to these communities is difficult and, in most cases, these women do not have access to primary care and public health services.

Abstract Background Scorpionism is a serious public health problem in Brazil. Although cases of envenomation by scorpions are frequent in Brazil, Tityus silvestris – found throughout the Amazon region – is considered of minor medical significance and with only a few descriptions in the literature. This article aims to describe for the first time the epidemiological characteristics and clinical manifestations of scorpion stings by T. silvestris that occurred in eastern Brazilian Amazon. Methods A prospective and observational study was carried out on 13 confirmed cases of T. silvestris envenomation registered from 2007 to 2011 in the cities of Belém and Ananindeua, Pará state, Brazil. Results The stings occurred mainly during daytime, at domiciliary environment, and the scorpions were found in clothing, fruits or vegetables. Envenomation was more frequent in the age group between 21 and 30 years old, upper limbs were more affected and medical aid was usually provided within two hours. Men and women were equally affected. Regarding severity, ten patients were classified as Class I and three patients as Class II according to the Scorpion Consensus Expert Group. Local manifestations were present in all patients, being pain the most common symptom. Mild systemic manifestations including nausea, vomiting, somnolence, malaise and prostration were observed in three victims. Symptomatic treatment of pain was offered to all patients, and only one received specific antivenom. All victims had a favorable outcome. Conclusions To the best of our knowledge, this study is the first to report the systemic symptomatology of envenomation by T. silvestris in the Brazilian Amazon, highlighting the medical relevance of the species in this region. Further research on the venom and clinical manifestations of envenomation by T. silvestris should be conducted in order to verify the relevance of this species to public health.

AbstractBackground Bonito municipality, known as an area of ecoturism, in Mato Grosso do Sul state, Brazil, is also a focus of visceral and cutaneous leishmaniases, with cases registered in both human and canine populations. This study sought to investigate natural infection by flagellate forms of Leishmania in phlebotomines of the urban area of Bonito.Findings Sand flies were collected fortnightly from October 2005 to July 2006 with modified automatic light traps installed in peridomiciles and animal shelters in the center and on the outskirts of the city. The females were dissected and their guts observed under an optical microscope. A total of 1977 specimens were captured, Lutzomyia longipalpis (88.4 %) and Bichromomyia flaviscutelata (3.0 %) being the most frequent species. Bi. flaviscutellata was found infected by flagellates that were identified as Leishmania (Leishmania) amazonensis by indirect immunofluorescence reaction, employing monoclonal antibodies and the biotin-avidin system. This is the first report of natural infection by L. amazonensis in Bi. flaviscutellata in a Brazilian urban area.Conclusions As Bi. flaviscutellata is only slightly attracted by humans, the transmission of L. amazonensis in the study area may have a zoonotic character; however, the sympatric occurrence of this parasite andLu. longipalpis should be taken into consideration by the local health authorities since this sand fly has already been found with L. amazonensis DNA in a focus of canine visceral leishmaniasis in Bonito municipality.

IntroductionKala-azar is a disease resulting from infection by Leishmania donovani and Leishmania infantum. Most patients with the disease exhibit prolonged fever, wasting, anemia and hepatosplenomegaly without complications. However, some patients develop severe disease with hemorrhagic manifestations, bacterial infections, jaundice, and edema dyspnea, among other symptoms, followed by death. Among the parasite molecules that might influence the disease severity are the macrophage migration inhibitory factor-like proteins (MIF1 and MIF2) and N-acetylglucosamine-1-phosphotransferase (NAGT), which act in the first step of protein N-glycosylation. This study aimed to determine whether MIF1, MIF2 and NAGT are virulence factors for severe kala-azar.MethodsTo determine the parasite genotype in kala-azar patients from Northeastern Brazil, we sequenced the NAGT genes of L. infantum from 68 patients as well as the MIF1 and MIF2 genes from 76 different subjects with diverse clinical manifestations. After polymerase chain reaction (PCR), the fragments were sequenced, followed by polymorphism identification.ResultsThe nucleotide sequencing of the 144 amplicons revealed the absence of genetic variability of the NAGT, MIF1 and MIF2 genes between the isolates. The conservation of these genes suggests that the clinical variability of kala-azar does not depend upon these genes. Additionally, this conservation suggests that these genes may be critical for parasite survival.ConclusionsNAGT, MIF1 and MIF2 do not alter the severity of kala-azar. NAGT, MIF1 and MIF2 are highly conserved among different isolates of identical species and exhibit potential for use in phylogenetic inferences or molecular diagnosis.

The aim of the present study was to detect natural infection by Leishmania (Leishmania) infantum in Lutzomyia longipalpis captured in Barcarena, state of Pará, Brazil, through the use of three primer sets. With this approach, it is unnecessary to previously dissect the sandfly specimens. DNA of 280 Lu. longipalpis female specimens were extracted from the whole insects. PCR primers for kinetoplast minicircle DNA (kDNA), the mini-exon gene and the small subunit ribosomal RNA (SSU-rRNA) gene of Leishmania were used, generating fragments of 400 bp, 780 bp and 603 bp, respectively. Infection by the parasite was found with the kDNA primer in 8.6% of the cases, with the mini-exon gene primer in 7.1% of the cases and with the SSU-rRNA gene primer in 5.3% of the cases. These data show the importance of polymerase chain reaction as a tool for investigating the molecular epidemiology of visceral leishmaniasis by estimating the risk of disease transmission in endemic areas, with the kDNA primer representing the most reliable marker for the parasite.

IntroductionThis study investigated the occurrence of Strongyloides stercoralis infestation and coinfection with HTLV-1/2 in Belém, Brazil.MethodsS. stercoralis was investigated in stool samples obtained from individuals infected with HTLV-1/2 and their uninfected relatives.ResultsThe frequency of S. stercoralis was 9% (9/100), including six patients infected with HTLV-1 (14.3%), two patients infected with HTLV-2 (11.1%), and one uninfected relative. Two cases of hyperinfestation by S. stercoralis were characterized as HTLV-1.ConclusionsThese results support the need for the routine investigation of S. stercoralis in patients with HTLV-1, in an attempt to prevent the development of severe forms of strongyloidiasis.

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.