Oropouche fever is caused by Oropouche virus (OROV), transmitted primarily through the bite of infected midges, particularly of the genusCulicoides. The virus is mainly circulating in Central and South America where several countries reported an ongoing outbreak. We report here two imported cases of OROV infection identified in Italy, late May–early June 2024. These cases indicate that in the shadow of a massive dengue outbreak in the Americas, the Oropouche outbreak might be more widespread than previously estimated.

Resting T lymphocytes can internalize reduced cysteine (Cys) but not cystine, the oxidized form of the amino acid that predominates extracellularly. In vitro studies have shown that DC provide Cys to T cells during antigen presentation, allowing their activation. Here, we show that increased thiol production is a hallmark of immune response in vivo. Indeed, the thiol content of LN increases dramatically after antigen injection. Non‐protein thiols co‐distribute with DC and are highly abundant in germinal centers. In agreement, activated but not resting B lymphocytes and macrophages release free thiols. Increased thiol release following activation requires thioredoxin and is paralleled by increased thioredoxin expression. The T zones of LN are consistently less stained, and both resting and activated T cells are unable to release thiols. Interestingly, the cystine/glutamate transporter x is absent in resting T lymphocytes but is rapidly induced by TCR triggering in vitro, indicating that the release of T cells from the need of exogenous Cys occurs early after activation. These results indicate that a reducing microenvironment is essential to start the immune response but dispensable for its evolution, and support the emerging concept that extracellular redox is implicated in the control of crucial cellular functions.

On 27 May 2024, the Cuban Ministry of Health reported the first outbreak of Oropouche fever on the island. The etiologic agent, Oropouche virus (OROV), is a poorly understood arbovirus that has been known since the 1960s and represents a public health burden in Latin America. We report the whole-genome characterization of the first European OROV isolate from a returning traveler from Cuba with Oropouche fever-like symptoms. The isolate was obtained from the patient’s serum; whole-genome sequencing was performed by next-generation sequencing, followed by phylogenetic analysis and genetic variability studies. The analysis showed that the most closely related sequence was from the French Guiana 2020 outbreak. Interestingly, our isolate is a reassortant virus, included in a highly supported monophyletic clade containing recent OROV cases (Brazil 2015–Colombia 2021), separated from the other four previously known genotypes. More deeply, it was found to be included in a distinct branch containing the sequences of the Brazil 2022–2024 outbreak. The reassortment event involved the S and L segments, which have high similarity with sequences belonging to a new cluster (here defined as OROV_SCDC_2024), while the M segment shows high similarity with older sequences. These results likely describe the viral strain responsible for the current outbreak in Cuba, which may also reflect the ongoing outbreak in Latin America. Further studies are needed to understand how OROV evolves towards traits that facilitate its spread and adaptation outside its original basin, and to track its spread and evolution in the European continent.

Italian beef production is mainly based on a feedlot system where calves are housed with mixed aged cattle often in conditions favourable to bovine respiratory disease (BRD). In Veneto, an indoor system is also used for imported bulls around 300–350 kg. Mycoplasmas, in particular Mycoplasma bovis and Mycoplasma dispar, contribute to BRD in young calves, but their role in the disease in older cattle has not been investigated. In this study, ten heads of cattle were selected from each of the 24 groups kept in 13 different farms. Bulls were sampled by nasal swabbing at 0, 15, and 60 days after arrival for Mycoplasma isolation. Identification was carried out by 16S-rDNA PCR followed by denaturing gradient gel electrophoresis. M. bovis, M. dispar, and M. bovirhinis were identified, and prevalence was analysed by mixed-effects logistic regression models. This showed that most bulls arrived free of M. bovis, but within two weeks, approximately 40% became infected, decreasing to 13% by the last sampling. In contrast, the prevalence of M. dispar was not dependent on time or seasonality, while M. bovirhinis only showed a seasonality-dependent trend. The Italian fattening system creates an ideal environment for infection with M. bovis, probably originating from previously stabled animals.

Mycoplasma gallisepticum (MG) infects many avian species and leads to significant economic losses in the poultry industry. Transmission of this pathogen occurs both horizontally and vertically, and strategies to avoid the spread of MG rely on vaccination and the application of biosecurity measures to maintain breeder groups as pathogen-free. Two live attenuated MG vaccine strains are licensed in Italy: 6/85 and ts-11. After their introduction, the implementation of adequate genotyping tools became necessary to distinguish between field and vaccine strains and to guarantee proper infection monitoring activity. In this study, 40 Italian MG isolates collected between 2010–2019 from both vaccinated and unvaccinated farms were genotyped using gene-targeted sequencing (GTS) of the cythadesin gene mgc2 and multilocus sequence typing (MLST) based on six housekeeping genes. The discriminatory power of GTS typing ensures 6/85-like strain identification, but the technique does not allow the identification ts-11 strains; conversely, MLST differentiates both vaccine strains, describing more detailed interrelation structures. Our study describes MG genetic scenario within a mixed farming context. In conclusion, the use of adequate typing methods is essential to understand the evolutionary dynamics of MG strains in a particular area and to conduct epidemiological investigations in the avian population.