SARS-CoV-2 intra-host diversity, antibody response, and disease severity after reinfection by the variant of concern Gamma in Brazil.

The rapid spread of the SARS-CoV-2 Variant of Concern (VOC) Gamma in Amazonas during early 2021 fueled a second large COVID-19 epidemic wave and raised concern about the potential role of reinfections. Very few cases of reinfection associated with the VOC Gamma have been reported to date, and their potential impact on clinical, immunological, and virological parameters remains largely unexplored. Here we describe 25 cases of SARS-CoV-2 reinfection in Brazil. SARS-CoV-2 genomic analysis confirmed that individuals were primo-infected with distinct viral lineages between March and December 2020 (B.1.1, B.1.1.28, B.1.1.33, B.1.195, and P.2) and reinfected with the VOC Gamma between 3 to 12 months after primo-infection. We found a similar mean cycle threshold (Ct) value and limited intra-host viral diversity in both primo-infection and reinfection samples. Sera of 14 patients tested 10-75 days after reinfection displayed detectable neutralizing antibodies (NAb) titers against SARS-CoV-2 variants that circulated before (B.1.*), during (Gamma), and after (Delta and Omicron) the second epidemic wave in Brazil. All individuals had milder or no symptoms after reinfection, and none required hospitalization. These findings demonstrate that individuals reinfected with the VOC Gamma may display relatively high RNA viral loads at the upper respiratory tract after reinfection, thus contributing to onward viral transmissions. Despite this, our study points to a low overall risk of severe Gamma reinfections, supporting that the abrupt increase in hospital admissions and deaths observed in Amazonas and other Brazilian states during the Gamma wave was mostly driven by primary infections. Our findings also indicate that most individuals analyzed developed a high anti-SARS-CoV-2 NAb response after reinfection that may provide some protection against reinfection or disease by different SARS-CoV-2 variants.

Comparative epidemic expansion of SARS-CoV-2 variants Delta and Omicron in the Brazilian State of Amazonas.

The SARS-CoV-2 variants of concern (VOCs) Delta and Omicron spread globally during mid and late 2021, respectively. In this study, we compare the dissemination dynamics of these VOCs in the Amazonas state, one of Brazil's most heavily affected regions. We sequenced the virus genome from 4128 patients collected in Amazonas between July 1st, 2021, and January 31st, 2022, and investigated the viral dynamics using a phylodynamic approach. The VOCs Delta and Omicron BA.1 displayed similar patterns of phylogeographic spread but different epidemic dynamics. The replacement of Gamma by Delta was gradual and occurred without an upsurge of COVID-19 cases, while the rise of Omicron BA.1 was extremely fast and fueled a sharp increase in cases. Thus, the dissemination dynamics and population-level impact of new SARS-CoV-2 variants introduced in the Amazonian population after mid-2021, a setting with high levels of acquired immunity, greatly vary according to their viral phenotype.

Increased Serum Levels of Growth-Differentiation Factor 3 (GDF3) and Inflammasome-Related Markers in Pregnant Women during Acute Zika Virus Infection.

The systemic inflammatory response elicited by acute Zika virus (ZIKV) infection during pregnancy plays a key role in the clinical outcomes in mothers and congenitally infected offspring. The present study aimed to evaluate the serum levels of GDF-3 and inflammasome-related markers in pregnant women during acute ZIKV infection. Serum samples from pregnant (n = 18) and non-pregnant (n = 22) women with acute ZIKV infection were assessed for NLRP3, IL-1ß, IL-18, and GDF3 markers through an enzyme-linked immunosorbent assay. ZIKV-negative pregnant (n = 18) and non-pregnant women (n = 15) were used as control groups. All serum markers were highly elevated in the ZIKV-infected groups in comparison with control groups (p < 0.0001). Among the ZIKV-infected groups, the serum markers were significantly augmented in the pregnant women in comparison with non-pregnant women (NLRP3 p < 0.001; IL-1ß, IL-18, and GDF3 p < 0.0001). The IL-18 marker was found at significantly higher levels (p < 0.05) in the third trimester of pregnancy. Bivariate and multivariate analyses showed a strong positive correlation between GDF3 and NLRP3 markers among ZIKV-infected pregnant women (r = 0.91, p < 0.0001). The findings indicated that acute ZIKV infection during pregnancy induces the overexpression of GDF-3 and inflammasome-related markers, which may contribute to congenital disorders and harmful pregnancy outcomes.

Spread of Gamma (P.1) Sub-Lineages Carrying Spike Mutations Close to the Furin Cleavage Site and Deletions in the N-Terminal Domain Drives Ongoing Transmission of SARS-CoV-2 in Amazonas, Brazil.

The Amazonas was one of the most heavily affected Brazilian states by the COVID-19 epidemic. Despite a large number of infected people, particularly during the second wave associated with the spread of the Variant of Concern (VOC) Gamma (lineage P.1), SARS-CoV-2 continues to circulate in the Amazonas. To understand how SARS-CoV-2 persisted in a human population with a high immunity barrier, we generated 1,188 SARS-CoV-2 whole-genome sequences from individuals diagnosed in the Amazonas state from 1st January to 6th July 2021, of which 38 were vaccine breakthrough infections. Our study reveals a sharp increase in the relative prevalence of Gamma plus (P.1+) variants, designated Pango Lineages P.1.3 to P.1.6, harboring two types of additional Spike changes: deletions in the N-terminal (NTD) domain (particularly Δ144 or Δ141-144) associated with resistance to anti-NTD neutralizing antibodies or mutations at the S1/S2 junction (N679K or P681H) that probably enhance the binding affinity to the furin cleavage site, as suggested by our molecular dynamics simulations. As lineages P.1.4 (S:N679K) and P.1.6 (S:P681H) expanded (Re > 1) from March to July 2021, the lineage P.1 declined (Re < 1) and the median Ct value of SARS-CoV-2 positive cases in Amazonas significantly decreases. Still, we did not find an increased incidence of P.1+ variants among breakthrough cases of fully vaccinated patients (71%) in comparison to unvaccinated individuals (93%). This evidence supports that the ongoing endemic transmission of SARS-CoV-2 in the Amazonas is driven by the spread of new local Gamma/P.1 sublineages that are more transmissible, although not more efficient to evade vaccine-elicited immunity than the parental VOC. Finally, as SARS-CoV-2 continues to spread in human populations with a declining density of susceptible hosts, the risk of selecting more infectious variants or antibody evasion mutations is expected to increase. IMPORTANCE The continuous evolution of SARS-CoV-2 is an expected phenomenon that will continue to happen due to the high number of cases worldwide. The present study analyzed how a Variant of Concern (VOC) could still circulate in a population hardly affected by two COVID-19 waves and with vaccination in progress. Our results showed that the answer behind that was a new generation of Gamma-like viruses, which emerged locally carrying mutations that made it more transmissible and more capable of spreading, partially evading prior immunity triggered by natural infections or vaccines. With thousands of new cases daily, the current pandemics scenario suggests that SARS-CoV-2 will continue to evolve and efforts to reduce the number of infected subjects, including global equitable access to COVID-19 vaccines, are mandatory. Thus, until the end of pandemics, the SARS-CoV-2 genomic surveillance will be an essential tool to better understand the drivers of the viral evolutionary process.

COVID-19 in Amazonas, Brazil, was driven by the persistence of endemic lineages and P.1 emergence.

The northern state of Amazonas is among the regions in Brazil most heavily affected by the COVID-19 epidemic and has experienced two exponentially growing waves, in early and late 2020. Through a genomic epidemiology study based on 250 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genomes from different Amazonas municipalities sampled between March 2020 and January 2021, we reveal that the first exponential growth phase was driven mostly by the dissemination of lineage B.1.195, which was gradually replaced by lineage B.1.1.28 between May and June 2020. The second wave coincides with the emergence of the variant of concern (VOC) P.1, which evolved from a local B.1.1.28 clade in late November 2020 and replaced the parental lineage in <2 months. Our findings support the conclusion that successive lineage replacements in Amazonas were driven by a complex combination of variable levels of social distancing measures and the emergence of a more transmissible VOC P.1 virus. These data provide insights to understanding the mechanisms underlying the COVID-19 epidemic waves and the risk of dissemination of SARS-CoV-2 VOC P.1 in Brazil and, potentially, worldwide.

Three SARS-CoV-2 reinfection cases by the new Variant of Concern (VOC) P.1/501Y.V3

Neste relatório (pre-print), são apresentados três casos de reinfecção causados pela Variante de Preocupação (VOC) P.1, também conhecida como "cepa de Manaus". As três pacientes eram mulheres adultas, e tiveram a primeira infecção durante a primeira onda da pandemia na primeira metade de 2020. Nos três casos, a linhagem detectada no primeiro diagnóstico molecular era diferente da encontrada posteriormente, evidência da reinfecção. Dois dos casos de reinfecção tiveram apresentação de sintomas leves, enquanto o terceiro foi assintomático, apesar de a quantidade de material genético viral detectado sugerir cargas virais elevadas. As evidências aqui apresentadas sugerem que a imunidade após infecção primária por linhagens anteriores à circulação daquelas contendo a mutação E484K não impede uma nova infecção pela variante P.1, e nem mesmo que pessoas reinfectadas por esta variante espalhem o vírus, embora seja possível que tenha protegido estas três pacientes do desenvolvimento de sintomas graves.

Multifunctional T cell response in convalescent patients two years after ZIKV infection.

Zika is an important emerging infectious disease in which the role of T cells remains elusive. This study aimed to evaluate the phenotype of multifunctional T cells in individuals 2 yr after exposure to Zika virus (ZIKV). We used a library of 671 synthetic peptides covering the whole polyprotein of ZIKV in pools corresponding to each viral protein (i.e., capsid, membrane precursor or prM, envelope, NS1 [nonstructural protein], NS2A + NS2B, NS3, NS4A + NS4B, and NS5) to stimulate PBMCs from individuals previously exposed to ZIKV. We observed an increased frequency of ZIKV-specific IFNγ, IL-17A, TNF, and IL-10 production by T cell populations. IFNγ and TNF production were especially stimulated by prM, capsid, or NS1 in CD8+ T cells and by capsid or prM in CD4+ T cells. In addition, there was an increase in the frequency of IL-10+ CD8+ T cells after stimulation with prM, capsid, NS1, NS3, or NS5. Multifunctional properties were observed in ZIKV-specific T cells responding especially to prM, capsid, NS1 or, to a smaller extent, NS3 antigens. For example, we found a consistent IFNγ + TNF+ CD8+ T cell population in response to most virus antigens and CD4+ and CD8+ T cells that were IFNγ + IL-17A+ and IL-17A+IL-10+, which could also produce TNF, in response to capsid, prM, NS1, or NS3 stimulation. Interestingly, CD8+ T cells were more prone to a multifunctional phenotype than CD4+ T cells, and multifunctional T cells were more efficient at producing cytokines than single-function cells. This work provides relevant insights into the quality of ZIKV-specific T cell responses and ZIKV immunity.

Oropouche virus detection in saliva and urine.

Oropouche virus (OROV) is an arthropod-borne virus of the Peribunyaviridae family, transmitted to humans primarily by Culicoides paraensis. It is one of the main arboviruses infecting humans in Brazil, primarily in the Amazon Region. Here, we report the detection of OROV in the saliva and urine of a patient whose samples were collected five days after the onset of symptoms. Nucleotide sequencing and phylogenetic analysis further confirmed the results. To our knowledge, this is the first study reporting the detection of OROV in the saliva and urine of an infected patient. In addition, the results of our study expand the current knowledge pertaining to the natural history of Oropouche fever.

Oropouche virus detection in saliva and urine

Oropouche virus (OROV) is an arthropod-borne virus of the Peribunyaviridae family, transmitted to humans primarily by Culicoides paraensis. It is one of the main arboviruses infecting humans in Brazil, primarily in the Amazon Region. Here, we report the detection of OROV in the saliva and urine of a patient whose samples were collected five days after the onset of symptoms. Nucleotide sequencing and phylogenetic analysis further confirmed the results. To our knowledge, this is the first study reporting the detection of OROV in the saliva and urine of an infected patient. In addition, the results of our study expand the current knowledge pertaining to the natural history of Oropouche fever.

Ascaris lumbricoides coinfection reduces tissue damage by decreasing IL-6 levels without altering clinical evolution of pulmonary tuberculosis or Th1/Th2/Th17 cytokine profile.

INTRODUCTION: Immunological control of Mycobacterium tuberculosis infection is dependent on the cellular immune response, mediated predominantly by Th1 type CD4+ T cells. Polarization of the immune response to Th2 can inhibit the host immune protection against pathogens. Patients with tuberculosis coinfected with helminths demonstrate more severe pulmonary symptoms, a deficiency in the immune response against tuberculosis, and an impaired response to anti-tuberculosis therapy. METHODS: We evaluated the cellular immune response and the impact of the presence of Ascaris lumbricoides on the immune and clinical response in pulmonary tuberculosis patients. Ninety-one individuals were included in the study: 38 tuberculosis patients, 11 tuberculosis patients coinfected with Ascaris lumbricoides and other helminths, 10 Ascaris lumbricoides patients, and 34 non-infected control individuals. Clinical evolution of pulmonary tuberculosis was studied on 0, 30, 60, and 90 days post-diagnosis of Mycobacterium tuberculosis and Ascaris lumbricoides. Furthermore, immune cells and plasma cytokine profiles were examined in mono/coinfection by Mycobacterium tuberculosis and Ascaris lumbricoides using flow cytometry. RESULTS: There were no statistical differences in any of the evaluated parameters and the results indicated that Ascaris lumbricoides infection does not lead to significant clinical repercussions in the presentation and evolution of pulmonary tuberculosis. CONCLUSIONS: The association with Ascaris lumbricoides did not influence the Th1, Th2, and Th17 type responses, or the proportions of T lymphocyte subpopulations. However, higher serum levels of IL-6 in tuberculosis patients may explain the pulmonary parenchymal damage.

Ascaris lumbricoides coinfection reduces tissue damage by decreasing IL-6 levels without altering clinical evolution of pulmonary tuberculosis or Th1/Th2/Th17 cytokine profile

Abstract INTRODUCTION: Immunological control of Mycobacterium tuberculosis infection is dependent on the cellular immune response, mediated predominantly by Th1 type CD4+ T cells. Polarization of the immune response to Th2 can inhibit the host immune protection against pathogens. Patients with tuberculosis coinfected with helminths demonstrate more severe pulmonary symptoms, a deficiency in the immune response against tuberculosis, and an impaired response to anti-tuberculosis therapy. METHODS: We evaluated the cellular immune response and the impact of the presence of Ascaris lumbricoides on the immune and clinical response in pulmonary tuberculosis patients. Ninety-one individuals were included in the study: 38 tuberculosis patients, 11 tuberculosis patients coinfected with Ascaris lumbricoides and other helminths, 10 Ascaris lumbricoides patients, and 34 non-infected control individuals. Clinical evolution of pulmonary tuberculosis was studied on 0, 30, 60, and 90 days post-diagnosis of Mycobacterium tuberculosis and Ascaris lumbricoides. Furthermore, immune cells and plasma cytokine profiles were examined in mono/coinfection by Mycobacterium tuberculosis and Ascaris lumbricoides using flow cytometry. RESULTS: There were no statistical differences in any of the evaluated parameters and the results indicated that Ascaris lumbricoides infection does not lead to significant clinical repercussions in the presentation and evolution of pulmonary tuberculosis. CONCLUSIONS: The association with Ascaris lumbricoides did not influence the Th1, Th2, and Th17 type responses, or the proportions of T lymphocyte subpopulations. However, higher serum levels of IL-6 in tuberculosis patients may explain the pulmonary parenchymal damage.

Analysis of the immunological biomarker profile during acute Zika virus infection reveals the overexpression of CXCL10, a chemokine linked to neuronal damage.

BACKGROUND: Infection with Zika virus (ZIKV) manifests in a broad spectrum of disease ranging from mild illness to severe neurological complications and little is known about Zika immunopathogenesis. OBJECTIVES: To define the immunologic biomarkers that correlate with acute ZIKV infection. METHODS: We characterized the levels of circulating cytokines, chemokines, and growth factors in 54 infected patients of both genders at five different time points after symptom onset using microbeads multiplex immunoassay; comparison to 100 age-matched controls was performed for statistical analysis and data mining. FINDINGS: ZIKV-infected patients present a striking systemic inflammatory response with high levels of pro-inflammatory mediators. Despite the strong inflammatory pattern, IL-1Ra and IL-4 are also induced during the acute infection. Interestingly, the inflammatory cytokines IL-1ß, IL-13, IL-17, TNF-α, and IFN-γ; chemokines CXCL8, CCL2, CCL5; and the growth factor G-CSF, displayed a bimodal distribution accompanying viremia. While this is the first manuscript to document bimodal distributions of viremia in ZIKV infection, this has been documented in other viral infections, with a primary viremia peak during mild systemic disease and a secondary peak associated with distribution of the virus to organs and tissues. MAIN CONCLUSIONS: Biomarker network analysis demonstrated distinct dynamics in concurrence with the bimodal viremia profiles at different time points during ZIKV infection. Such a robust cytokine and chemokine response has been associated with blood-brain barrier permeability and neuroinvasiveness in other flaviviral infections. High-dimensional data analysis further identified CXCL10, a chemokine involved in foetal neuron apoptosis and Guillain-Barré syndrome, as the most promising biomarker of acute ZIKV infection for potential clinical application.

Atrial fibrillation in a patient with Zika virus infection.

BACKGROUND: Zika virus is an emerging arbovirus of the family Flaviviridae and genus Flavivirus that until 2007 was restricted to a few cases of mild illness in Africa and Asia. CASE PRESENTATION: We report a case of atrial fibrillation disclosed during an acute Zika virus infection in a 49-year-old man. Different biological samples were analyzed for the molecular diagnosis of Zika by real-time PCR, however only the saliva specimen was positive. The patient's wife tested positive in the serum sample, although she was an asymptomatic carrier. Moreover, a complete overview of patient's biomarkers, including cytokines, chemokines, and growth-factors levels, was analyzed and compared to gender and age matching non-infected controls, as well as other Zika infected patients, considering the 95%CI of the mean values. Elevated levels of CXCL8, CCL11, CCL2, CXCL10, IL-1ß, IL-6, TNF-α, IFN-γ, IL-17, IL-1Ra, IL-4, IL-9, FGF-basic, PDGF, G-CSF, and GM-CSF were observed in the Atrial fibrillation patient, in contrast to uninfected controls. Furthermore, increased levels of CCL5, IL-1ß, TNF-α, IFN-γ, IL-9, G-CSF, and GM-CSF were observed only in the atrial fibrillation patient, when compared to other Zika patients. CONCLUSIONS: To our knowledge, this is the first description of this type of cardiac disorder in Zika patients which may be considered another atypical manifestation during Zika virus infection.

Analysis of the immunological biomarker profile during acute Zika virus infection reveals the overexpression of CXCL10, a chemokine linked to neuronal damage

BACKGROUND Infection with Zika virus (ZIKV) manifests in a broad spectrum of disease ranging from mild illness to severe neurological complications and little is known about Zika immunopathogenesis. OBJECTIVES To define the immunologic biomarkers that correlate with acute ZIKV infection. METHODS We characterized the levels of circulating cytokines, chemokines, and growth factors in 54 infected patients of both genders at five different time points after symptom onset using microbeads multiplex immunoassay; comparison to 100 age-matched controls was performed for statistical analysis and data mining. FINDINGS ZIKV-infected patients present a striking systemic inflammatory response with high levels of pro-inflammatory mediators. Despite the strong inflammatory pattern, IL-1Ra and IL-4 are also induced during the acute infection. Interestingly, the inflammatory cytokines IL-1β, IL-13, IL-17, TNF-α, and IFN-γ; chemokines CXCL8, CCL2, CCL5; and the growth factor G-CSF, displayed a bimodal distribution accompanying viremia. While this is the first manuscript to document bimodal distributions of viremia in ZIKV infection, this has been documented in other viral infections, with a primary viremia peak during mild systemic disease and a secondary peak associated with distribution of the virus to organs and tissues. MAIN CONCLUSIONS Biomarker network analysis demonstrated distinct dynamics in concurrence with the bimodal viremia profiles at different time points during ZIKV infection. Such a robust cytokine and chemokine response has been associated with blood-brain barrier permeability and neuroinvasiveness in other flaviviral infections. High-dimensional data analysis further identified CXCL10, a chemokine involved in foetal neuron apoptosis and Guillain-Barré syndrome, as the most promising biomarker of acute ZIKV infection for potential clinical application.

Severe Hemorrhagic Syndrome After Lonomia Caterpillar Envenomation in the Western Brazilian Amazon: How Many More Cases Are There?

Contact with Lonomia caterpillars can cause a hemorrhagic syndrome. In Brazil, Lonomia obliqua and Lonomia achelous are known to cause this venom-induced disease. In the Brazilian Amazon, descriptions of this kind of envenomation are scarce. Herein, we report a severe hemorrhagic syndrome caused by Lonomia envenomation in the Amazonas state, Western Brazilian Amazon. The patient showed signs of hemorrhage lasting 8 days and required Lonomia antivenom administration, which resulted in resolution of hemorrhagic syndrome. Thus, availability of Lonomia antivenom as well as early antivenom therapy administration should be addressed across remote areas in the Amazon.

Severe hemorrhagic syndrome after lonomia caterpillar envenomation in the western Brazilian Amazon: how many more cases are there?

Contact with Lonomia caterpillars can cause a hemorrhagic syndrome. In Brazil, Lonomia obliqua and Lonomia achelous are known to cause this venom-induced disease. In the Brazilian Amazon, descriptions of this kind of envenomation are scarce. Herein, we report a severe hemorrhagic syndrome caused by Lonomia envenomation in the Amazonas state, Western Brazilian Amazon. The patient showed signs of hemorrhage lasting 8 days and required Lonomia antivenom administration, which resulted in resolution of hemorrhagic syndrome. Thus, availability of Lonomia antivenom as well as early antivenom therapy administration should be addressed across remote areas in the Amazon.

Risk Factors for Mycobacterium abscessus subsp. bolletii infection after laparoscopic surgery during an outbreak in Brazil.

OBJECTIVE To identify risk factors related to Mycobacterium abscessus subsp. bolletii infection during an outbreak, associated with laparoscopic surgery and to propose recommendations for preventing new cases. DESIGN A retrospective cohort study. SETTING A private hospital in Manaus, Brazil. PATIENTS A cohort of 222 patients who underwent laparoscopic surgery between July 2009 and August 2010 by a single surgical team. METHODS We collected information about the patients and the surgical procedure using a standard form. We included sex, age, and variables with P≤0.2 in the bivariate analysis in a logistic regression model. Additionally, we reviewed the procedures for reprocessing the laparoscopic surgery equipment, and the strains obtained with culture were identified by molecular methods. RESULTS We recorded 60 (27%) cases of infection. After multivariate analysis, the duration of surgery beyond 1 hour (odds ratio [OR] 2.4; 95% confidence interval [CI] 1.2-4.5), not to have been the first operated patient on a given day (OR, 2.7; 95% CI, 1.4-5.2), and the use of permanent trocar (OR, 2.2; 95% CI, 1.1-4.2) were associated with infection. We observed that the surgical team attempted to sterilize the equipment in glutaraldehyde solution when sanitary authorities had already prohibited it. Eleven strains presented 100% DNA identity with a single strain, known as BRA100 clone. CONCLUSIONS Because contaminated material can act as vehicle for infection, ensuring adequate sterilization processing of video-assisted surgery equipment was crucial to stopping this single clonal outbreak of nonturbeculous mycobacteria in Brazil.

Mycobacterium leprae in the periodontium, saliva and skin smears of leprosy patients / Mycobacterium leprae no periodonto, saliva e raspados intradérmicos de sujeitos com hanseníase

Purpose: To verify the presence of M. leprae in the periodontium, saliva and skin slit smears of leprosy patients. To correlate bacteriological and molecular findings with clinical data and compare laboratory techniques. Methods: A cross-sectional study was designed to use bacteriological (baciloscopy) and molecular (PCR) parameters to detect M. leprae in exudates of the gingival sulcus/periodontium pocket, saliva and skin slit smears from multiple clinical forms of leprosy patients without previous treatment. Results: The study included 48 leprosy patients with 15 multibacillary (MB) cases and 33 paucibacillary (PB) cases. The diagnosis of MB was confirmed through bacteriological examination and PCR results from skin slit smears. A total of 16 (48.5%) PB patients were PCR positive only. Four PB patients with negative PCR skin smears were PCR positive for the periodontium and saliva, with 2 cases and 1 case, respectively. No periodontium or saliva samples had positive bacteriological results. Conclusion: There was no correlation between periodontal disease and the presence of M. leprae. Bacteriological examination did not prove to be an efficient technique for the analysis of saliva and periodontium samples. PCR analysis of skin smears was more efficient at diagnosing PB patients than bacteriological examination. PCR positive results for the detection of M. leprae in PB patients can be increased by collecting slit skin smears, periodontium and saliva samples.

Objetivo: verificar através da baciloscopia e da reação em cadeia da polimerase (PCR) a presença do M. leprae no periodonto, saliva e raspados intradérmicos de pacientes com hanseníase. Metodologia: Realizou-se um estudo transversal do tipo detecção de casos numa instituição referência de hanseníase no Amazonas. Resultados: Foram avaliados 48 pacientes, sendo 15 multibacilares (MB) e 33 paucibacilares (PB). Os pacientes MB tiveram o diagnóstico confirmado pela baciloscopia e PCR dos raspados intradérmicos, enquanto que 16 (48,5%) dos PB foram positivos apenas na PCR. Quatro pacientes PB negativos na PCR de raspados intradérmicos foram positivos no periodonto e na saliva, 1 positivo na saliva e 2 no periodonto. Nenhuma amostra do periodonto e da saliva foi positiva na baciloscopia. Conclusão: Não houve relação entre a doença periodontal e a presença do M. leprae; a baciloscopia não mostrou ser uma técnica eficiente para análise da saliva e periodonto; a técnica de PCR de raspado dérmico mostrou ser um método mais eficaz no diagnóstico dos PB do que a baciloscopia; a positividade da PCR para detecção do M. leprae nos PB pode ser aumentada coletando raspado intradérmico, periodonto e saliva.