A 4.2% positivity rate of was found among women in Pelotas, Brazil and the routine diagnostic test (wet mount microscopy) and culture had low sensitivities. More sensitive diagnostic tests (NAATs) and enhanced testing of symptomatic and asymptomatic at-risk women are crucial to mitigate the transmission of TV infection, TV-associated sequelae and enhanced HIV acquisition and transmission.

Background. Clinical recurrence of COVID-19 in convalescent patients has been reported, which immune mechanisms have not been thoroughly investigated. Presence of neutralizing antibodies suggests other types of immune response are involved. Methods. We assessed the innate type I/III IFN response, T cell responses to SARS-CoV-2 with IFNγ ELISPOT, binding and neutralizing antibody assays, in two monozygotic twin pairs with one COVID-19 recurrence case. Results. In pair 1, four months after a first mild episode of infection for both siblings, one displayed severe clinical recurrence of COVID-19. Twin pair 2 of siblings underwent non-recurring asymptomatic infection. All fours individuals presented similar overall responses, except for remarkably difference found in specific cellular responses. Recurring sibling presented a reduced number of recognized T cell epitopes as compared to the other three including her non-recurring sibling. Conclusions. Our results suggest that an effective SARS-CoV-2-specific T cell immune response is key for complete viral control and avoidance of clinical recurrence of COVID-19. Besides, adaptive immunity can be distinct in MZ twins. Given the rising concern about SARS-CoV-2 variants that evade neutralizing antibodies elicited by vaccination or infection, our study stresses the importance of T cell responses in protection against recurrence/reinfection.

A retrospective study of oral trichomoniasis cases in raptors was carried out at “Laboratório Regional de Diagnóstico” of “Faculdade de Veterinária” of “Universidade Federal de Pelotas” (LRD-UFPel) from December 2014 to August 2017. Seven necropsy reports were reviewed. All raptors including Falconiformes and Strigiformes orders were from periurban zones. Four birds were adults, and there was no apparent sex predisposition. Clinical signs included dysphagia, regurgitation, and anorexia. Gross lesions were characterized by multifocal yellow to coalescent caseous nodules adhered to the oral cavity, which extended to the entrance of the esophagus. Microscopically, the lesions were characterized by severe focally extensive heterophilic granulomatous stomatitis. Trichomonas gallinae was isolated in modified Diamond medium of all samples collected from birds. It is believed the transmission occurred by the predation of domestic pigeons (Columbia livia domestica) contaminated with T. gallinae that agglomerate in patios of grain processing complexes.

Recurrence of COVID-19 in recovered patients has been increasingly reported. However, the immune mechanisms behind the recurrence have not been thoroughly investigated. The presence of neutralizing antibodies (nAbs) in recurrence/reinfection cases suggests that other types of immune response are involved in protection against recurrence. Here, we investigated the innate type I/III interferon (IFN) response, binding and nAb assays and T-cell responses to severe acute respiratory distress syndrome coronavirus 2 (SARS-CoV-2) with IFN gamma (IFN γ ) enzyme-linked spot assay (ELISPOT) in three pairs of young adult monozygotic (MZ) twins with previous confirmed COVID-19, one of them presenting a severe recurrence four months after the initial infection. Twin studies have been of paramount importance to comprehend the immunogenetics of infectious diseases. Each MZ twin pair was previously exposed to SARS-CoV-2, as seen by clinical reports. The six individuals presented similar overall recovered immune responses except for the recurrence case, who presented a drastically reduced number of recognized SARS-CoV-2 T-cell epitopes on ELISPOT as compared to her twin sister and the other twin pairs. Our results suggest that the lack of a broad T-cell response to initial infection may have led to recurrence, emphasizing that an effective SARS-CoV-2-specific T-cell immune response is key for complete viral control and avoidance of clinical recurrence of COVID-19.

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