Background Diagnosis of active tuberculosis (ATB) currently relies on detection of M. tuberculosis (Mtb). Identifying patients with extrapulmonary TB (EPTB) remains challenging because microbiological confirmation is often not possible. Highly accurate blood-based tests could improve diagnosis of both EPTB and pulmonary TB (PTB), and timely initiation of anti-TB therapy. Methods A case-control study was performed using discriminant analyses to validate an approach using Mtb-specific CD4+T-cell activation markers in blood to discriminate PTB and EPTB from latent TB infection (LTBI) as well as EPTB from PTB in 270 Brazilian individuals. We further tested the effect of HIV co-infection on diagnostic performance. Frequencies of IFNγ+CD4+T-cells expressing CD38, HLADR, and/or Ki67 were assessed by flow cytometry. Results EPTB and PTB were associated with higher frequencies of CD4+T-cells expressing CD38, HLADR or Ki67 compared to LTBI (all p-values < .001). Moreover, frequencies of HLADR+ (p= .03) or Ki67+ (p< .001) cells accurately distinguished EPTB from PTB. HIV infection did not affect the capacity of these markers to distinguish ATB from LTBI or EPTB from PTB. Conclusion Cell activation markers in Mtb-specific CD4+T-cells distinguished ATB from LTBI, and EPTB from PTB, regardless of HIV infection status. These parameters provide an attractive approach for developing blood-based diagnostic tests for both active and latent TB.

RePORT-Brazil. Illicit drug use, the presence of diabetes, and history of prior TB were associated with unfavorable TB treatment outcomes; illicit drug use was associated with such outcomes in both cohorts. Conclusions: There were important similarities in demographic characteristics and determinants of clinical outcomes between the RePORT-Brazil cohort and the Brazilian National registry of TB cases.

Background It is unclear whether diabetes or prediabetes affect unfavorable treatment outcomes and death in people with tuberculosis (PWTB). Methods Culture-confirmed drug-susceptible PWTB, enrolled in Regional Prospective Observational Research in Tuberculosis (RePORT)-Brazil between 2015-2019 (n=643) were stratified based on glycemic status according to baseline glycated hemoglobin. Unfavorable TB outcome was defined as treatment failure or modification, recurrence or death; favorable outcome was cure or treatment completion. We corroborated the findings using data from PWTB reported to the Brazilian National System of Diseases Notification (SINAN) during 2015-2019 (n=20,989). Logistic regression models evaluated associations between glycemic status and outcomes. Results In both cohorts, in univariate analysis, unfavorable outcomes were more frequently associated with smoking, illicit drug use and HIV infection. Diabetes, but not prediabetes, was associated with unfavorable outcomes in the RePORT-Brazil (adjusted Relative Risk [aRR]: 2.45, p&lt;0.001) and SINAN (aRR: 1.76, p&lt;0.001) cohorts. Furthermore, diabetes was associated with high risk of death (during TB treatment) in both RePORT-Brazil (aRR:2.16, p=0.040) and SINAN (aRR:1.93, p= 0.001). Conclusion Diabetes was associated with an increased risk of unfavorable outcomes and mortality in Brazilian PWTB. Interventions to improve tuberculosis treatment outcomes in persons with diabetes are needed.

Porcine reproductive and respiratory syndrome virus (PRRSV) is an enveloped RNA virus responsible for PRRS in swine, a disease with globally significant animal welfare and economic concerns. There is no specific treatment and variably effective immune protection. Molecular mechanisms responsible for virulence, pathogenesis and protective immune response remain poorly understood. These factors limit progress towards development of effective measures for prevention and treatment of PRRS. A novel PRRSV ORF5a protein, encoded in an open reading frame (ORF) that overlaps the major envelope glycoprotein GP5 ORF, was recently identified. Because ORF5a is highly conserved in diverse PRRSV isolates, is a structural protein in the virion, and elicits a specific antibody response in infected pigs, we investigated its potential role in immune protection against PRRSV infection. Pigs immunized with ORF5a protein had robust serologic responses. However, the antibodies did not neutralize virus, and immunity did not protect against challenge infection. We conclude from these findings that the ORF5a antibody response is neither neutralizing nor protective.

Background It is unknown whether dysglycemia is associated with M. tuberculosis transmission. Methods We assessed epidemiological and clinical characteristics of patients with culture-confirmed pulmonary TB and their close contacts, enrolled in a multicenter prospective cohort in Brazil. Contacts were investigated at baseline and 6 months after enrollment. QuantiFERON positivity at baseline and conversion (from negative to positive at month 6) were compared between subgroups of contacts according to glycemic status of persons with tuberculosis (PWTB) as diabetes mellitus (DM) or prediabetes. Multivariable mixed-effects logistic regression models were performed to test independent associations with baseline QuantiFERON-positive and QuantiFERON-conversion. Results There were 592 PWTB (153 DM, 141 prediabetes, 211 normoglycemic) and 1784 contacts, of whom 658 were QuantiFERON-positive at baseline and 106 converters. Multivariable analyses demonstrated that TB-prediabetes cases, acid-fast bacilli-positive, pulmonary cavities, and living with someone who smoked, were independently associated with QuantiFERON-positive in contacts at baseline. DM, persistent cough, AFB-positive and pulmonary cavities in TB source cases were associated with QuantiFERON-conversion. Conclusion Contacts of persons with pulmonary TB and dysglycemia were at increased risk of being QuantiFERON-positive at baseline or month 6. Increased focus on such close contacts could improve TB control.