BackgroundVisceral leishmaniasis (VL) is a protozoan disease, which is responsible for 200.000–400.000 yearly infections worldwide. If left untreated, the fatality rate can be as high as 100% within 2 years. 90% of cases occur in just six countries: India, Bangladesh, Sudan, South Sudan, Ethiopia and Brazil. It is thus a disease rarely seen by physicians in Europe or North America. We report on the fatal case of VL in an 80-year-old immunosuppressed patient who presented with a latency of over 15 years after having visited an endemic region. This is the first report showing such extreme latency of VL in a European traveller. This case is furthermore unusual because it suggests primary treatment failure to liposomal amphotericin B.Case presentationAn 80-year-old man who was on immunosuppressive treatment due to a non-specific inflammatory disease of the liver and kidney presented to our hospital with recurrent fever, fatigue and bloody diarrhoea. Histopathological analysis from a colon biopsy showed intracellular amastigotes. The diagnosis of VL was confirmed by polymerase-chain-reaction (PCR) of the colon biopsy. PCR was also performed in plasma, a bronchopulmonary lavage, a lymph node, liver and bone marrow biopsy and proved L. donovani as causative species. The disseminated infection was unresponsive to treatment with liposomal amphotericin B as recommended in immunosuppressed individuals despite stopping immunosuppressive treatment.ConclusionImported cases of VL to non-endemic regions are increasing due to extensive international travel and migration. Furthermore, the increase of elderly patients and immunosuppressed individuals, secondary to HIV, post-transplant and chemotherapeutic agents, has resulted in an increase of VL also in endemic regions of Europe. It is thus important for physicians to be able to recognize the infection. This case also demonstrates treatment failure to amphotericin B, which was only a known problem in patients with HIV until now. The knowledge of this as a possible complication is important for specialists treating the disease.

Background BNT162b2 by Pfizer-BioNTech and mRNA-1273 by Moderna are the most commonly used vaccines to prevent SARS-CoV-2 infections. Head-to-head comparison of the efficacy of these vaccines in immunocompromised patients is lacking. Methods Parallel, two-arm (allocation 1:1), open-label, non-inferiority randomised clinical trial nested into the Swiss HIV Cohort Study and the Swiss Transplant Cohort Study. Patients living with HIV (PLWH) or solid organ transplant recipients (SOTR; i.e. lung and kidney) from these cohorts were randomised to mRNA-1273 or BNT162b2. The primary endpoint was antibody response to SARS-CoV-2 spike (S1) protein receptor binding domain (Elecsys Anti-SARS-CoV-2 immunoassay, Roche; cut-off ≥0.8 units/ml) 8 weeks after second vaccination. In addition, antibody response was measured with the Antibody CORonavirus Assay 2 (ABCORA 2). Results 430 patients were randomised and 412 were included in the intention-to-treat analysis (341 PLWH and 71 SOTR). The percentage of patients showing an immune response was 92.1% (95% confidence interval [CI] 88.4-95.8%; 186/202) for mRNA-1273 and 94.3% (95% CI 91.2-97.4; 198/210) for BNT162b2 (difference: 2.2%; 95% CI -7.1 to 2.7), fulfilling non-inferiority of mRNA-1273. With the ABCORA 2 test 89.1% had an immune response to mRNA-1273 (95% CI 84.8-93.4%; 180/202) and 89.5% to BNT162b2 (95% CI 85.4-93.7%; 188/210). Based on the Elecsys test, all PLWH had an antibody response (100.0%; 341/341), while for SOTR only 60.6% (95% CI 49.2-71.9%; 43/71) had titres above the cut-off. Conclusions In immunocompromised patients the antibody response of mRNA-1273 was non-inferior to BNT162b2. PLWH had in general an antibody response, while a high proportion of SOTR had no antibody response.

We identified determinants of SARS-CoV-2 mRNA vaccine antibody response in people with HIV (PWH). Antibody response was higher among PWH less than 60 years, with CD4+ cell count superior to 350 cells/μl and vaccinated with mRNA-1273 by Moderna compared with BNT162b2 by Pfizer-BioNTech. Preinfection with SARS-CoV-2 boosted the antibody response and smokers had an overall lower antibody response. Elderly PWH and those with low CD4+ cell count should be prioritized for booster vaccinations.