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BACKGROUNDImmunization against SARS-CoV-2, the causative agent of COVID-19, occurs via natural infection or vaccination. However, it is currently unknown how long infection- or vaccination-induced immunological memory will last.METHODSWe performed a longitudinal evaluation of immunological memory to SARS-CoV-2 up to 1 year after infection and following mRNA vaccination in naive individuals and individuals recovered from COVID-19 infection.RESULTSWe found that memory cells are still detectable 8 months after vaccination, while antibody levels decline significantly, especially in naive individuals. We also found that a booster injection is efficacious in reactivating immunological memory to spike protein in naive individuals, whereas it was ineffective in previously SARS-CoV-2-infected individuals. Finally, we observed a similar kinetics of decay of humoral and cellular immunity to SARS-CoV-2 up to 1 year following natural infection in a cohort of unvaccinated individuals.CONCLUSIONShort-term persistence of humoral immunity, together with the reduced neutralization capacity versus the currently prevailing SARS-CoV-2 variants, may account for reinfections and breakthrough infections. Long-lived memory B and CD4+ T cells may protect from severe disease development. In naive individuals, a booster dose restored optimal anti-spike immunity, whereas the needs for vaccinated individuals who have recovered from COVID-19 have yet to be defined.FUNDINGThis study was supported by funds to the Department of Experimental and Clinical Medicine, University of Florence (Project Excellence Departments 2018-2022), the University of Florence (project RICTD2122), the Italian Ministry of Health (COVID-2020-12371849), and the region of Tuscany (TagSARS CoV 2).

We report a case of hookworm infection presenting as recurrent severe anaemia in an adult Pakistani migrant to Italy. Clinicians working in non-endemic countries should be aware of this possible cause of anaemia, approachable by a microscopic stool examination that could avoid invasive and time-consuming diagnostic work-up.

The characterization of the adaptive immune response to COVID-19 vaccination in individuals who recovered from SARS-CoV-2 infection may define current and future clinical practice. To determine the effect of the 2-dose BNT162b2 mRNA COVID-19 vaccination schedule in individuals who recovered from COVID-19 (COVID-19–recovered subjects) compared with naive subjects, we evaluated SARS-CoV-2 Spike–specific T and B cell responses, as well as specific IgA, IgG, IgM, and neutralizing antibodies titers in 22 individuals who received the BNT162b2 mRNA COVID-19 vaccine, 11 of whom had a previous history of SARS-CoV-2 infection. Evaluations were performed before vaccination and then weekly until 7 days after second injection. Data obtained clearly showed that one vaccine dose is sufficient to increase both cellular and humoral immune response in COVID-19–recovered subjects without any additional improvement after the second dose. On the contrary, the second dose proved mandatory in naive subjects to further enhance the immune response. These findings were further confirmed at the serological level in a larger cohort of naive (n = 68) and COVID-19–recovered (n = 29) subjects, tested up to 50 days after vaccination. These results question whether a second vaccine injection in COVID-19–recovered subjects is required, and indicate that millions of vaccine doses may be redirected to naive individuals, thus shortening the time to reach herd immunity.

We report an atypical imported severe primary dengue presenting with neutrophilic leukocytosis, elevated inflammatory markers, myopericarditis and cardiac tamponade. Dengue Fever (DF) cannot be excluded in patients presenting with neutrophilic leukocytosis and elevated inflammatory markers which may anticipate severe dengue with myocardial involvement.

Purpose: Arbovirosis, viral infection transmitted by arthropods, is a widespread health problem. In Italy, as well for all Mediterranean basin, from late spring to the end of summer, Toscana Virus (TOSV), a sandfly borne virus, accounts for the majority of aseptic meningitis/meningoencephalitis cases. TOSV meningitis/meningoencephalitis has usually a self-extinguishing benign course. Our aim is to report a case of a young healthy women diagnosed with Toscana Virus meningoencephalitis with a complicated clinical course.Materials and methods/results: Case report of a 33-years old woman, admitted to the Infectious Diseases Unit at Careggi General Hospital (Florence-Italy), with a diagnosis of Toscana Virus meningoencephalitis. Seventy-two hours after the admission, she developed typical symptoms, as impaired legs coordination, slurred speech, stumbling and dysmetria, of acute cerebellar ataxia (ACA). Urgent neurological assessment was provided performing an electroencephalography study followed by a brain and brainstem magnetic resonance imaging. In the meanwhile, bilateral nystagmus arised. Through neurologist consultation ACA clinical diagnosis was then made and intravenous steroid therapy was administered with prompt symptoms resolution. The patient was finally discharged at day 10 since the ACA onset in good clinical conditions.Conclusions: To raise awareness among physicians about possible neurological complications during Toscana Virus meningoencephalitis.

Objectives Cases of undiagnosed severe febrile rhabdomyolysis in refugees coming from West Africa, mainly from Nigeria, has been observed since May 2014. The aim of this study was to describe this phenomenon. Methods This was a multicentre retrospective observational study of cases of febrile rhabdomyolysis reported from May 2014 to December 2016 in 12 Italian centres. Results A total of 48 cases were observed, mainly in young males. The mean time interval between the day of departure from Libya and symptom onset was 26.2 days. An average 8.3 further days elapsed before medical care was sought. All patients were hospitalized with fever and very intense muscle aches. Creatine phosphokinase, aspartate aminotransferase, and lactate dehydrogenase values were abnormal in all cases. The rhabdomyolysis was ascribed to an infective agent in 16 (33.3%) cases. In the remaining cases, the aetiology was undefined. Four out of seven patients tested had sickle cell trait. No alcohol abuse or drug intake was reported, apart from a single reported case of khat ingestion. Conclusions The long incubation period does not support a mechanical cause of rhabdomyolysis. Furthermore, viral infections such as those caused by coxsackievirus are rarely associated with such a severe clinical presentation. It is hypothesized that other predisposing conditions like genetic factors, unknown infections, or unreported non-conventional remedies may be involved. Targeted surveillance of rhabdomyolysis cases is warranted.