In a multicentre study, influenza A/H1N1/09v 222G/N variants were more frequently detected in patients admitted to the intensive-care unit for invasive mechanical ventilation or extracorporeal ...membrane oxygenation (10/23; 43.5%) than in patients hospitalized in other units (2/27; 7.4%) and community patients (0/81; 0.0%) (p <0.01). A significantly higher virus load (p 0.02) in the lower vs the upper respiratory tract was observed. Predominance of 222G/N variants in the lower respiratory tract (40% of total virus population) vs the upper respiratory tract (10%) was shown by clonal analysis of haemagglutinin sequences in paired nasal swab and bronchoalveolar lavage samples. The time from illness onset to sampling was significantly longer in patients with severe infection vs community patients (p <0.001). It was concluded that the 222G/N variants showed increased virulence; mutant variants were probably selected in individual patients; and the longer duration of illness might have favoured the emergence of adaptive mutations through multiple replication cycles.
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BFBNIB, DOBA, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, UILJ, UKNU, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Since December 2013, chikungunya virus (CHIKV) spread in many countries of the Western Hemisphere, and during the last year some cases of infected European travelers, coming back from the Caribbean, ...have been reported. The risk of acquiring severe travel‐related illness is higher in immunocompromised subjects, such as patients with human immunodeficiency virus (HIV) infection or solid organ transplant recipients. We reported the first case, to our knowledge, of CHIKV infection in an HIV‐infected kidney transplant recipient.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
The recent emergence of the Omicron variant has raised concerns on vaccine efficacy and the urgent need to study more efficient vaccination strategies. Here we observed that an mRNA vaccine booster ...in individuals vaccinated with two doses of inactivated vaccine significantly increased the plasma level of specific antibodies that bind to the receptor-binding domain (RBD) or the spike (S) ectodomain (S1 + S2) of both the G614 and the Omicron variants, compared to two doses of homologous inactivated vaccine. The level of RBD- and S-specific IgG antibodies and virus neutralization titers against variants of concern in the heterologous vaccination group were similar to that in individuals receiving three doses of homologous mRNA-vaccine or a boost of mRNA vaccine after infection, but markedly higher than that in individuals receiving three doses of a homologous inactivated vaccine. This heterologous vaccination regime furthermore significantly enhanced the RBD-specific memory B cell response and S1-specific T cell response, compared to two or three doses of homologous inactivated vaccine. Our study demonstrates that mRNA vaccine booster in individuals vaccinated with inactivated vaccines can be highly beneficial, as it markedly increases the humoral and cellular immune responses against the virus, including the Omicron variant.
The incidence of human cytomegalovirus (HCMV) disease in AIDS patients decreased dramatically after the introduction, a few years ago, of highly active antiretroviral combination therapy. As a ...consequence, the emergence of drug-resistant HCMV strains is no longer a major problem in HIV-infected individuals. However, HCMV resistance to antiviral drugs is presently recognized as an emerging problem in transplantation settings. The mechanisms of HCMV drug resistance will be analysed along with the clinical features relevant to the emergence of drug-resistant HCMV strains during antiviral treatment of patients receiving either solid organ or haematopoietic stem cell transplantation.
Ellis et al. reported that almost all viruses derived from fatal and non-fatal cases analysed (39/41) in the United Kingdom during the early wave of the 2010/11 influenza winter season showed the ...wild-type 222D haemagglutinin residue. Thus, in the paper by Ellis et al., severe and fatal influenza cases were not associated with the emergence of D222G/N mutants, even though the role of other amino acid substitutions remains to be determined. The authors of this study do not specify the type of clinical samples used for analysis. In the case they used nasal swabs only, on the basis of the above-referenced studies, the rate of D222G/N mutants might have been underestimated.
Abstract Background Monitoring the emergence of drug-resistant influenza variants is crucial in influenza surveillance programs. Objectives Influenza A kinetics and the emergence of drug-resistant ...strains in hospitalized patients treated with oseltamivir were investigated. Study design Sequential samples from oseltamivir-treated and -untreated hospitalized patients in the period November 2011 through April 2012 were analyzed. NA gene was sequenced in samples from oseltamivir treated patients. Clonal analysis of the viral population was performed in patients unresponsive to treatment. Viral kinetics was determined in 24 (14 immunocompromised and 10 immunocompetent) A(H3N2)-positive patients treated and 24 (10 immunocompromised and 14 immunocompetent) untreated patients. Results Viral shedding was significantly reduced in treated vs untreated immunocompromised patients (7 vs 22 days, p < 0.05, respectively). Viral load decreased significantly in immunocompromised and immunocompetent treated patients as compared with immunocompromised and immunocompetent untreated patients (0.73 and 0.93 vs 0.47 and 0.45 log10 /day, p < 0.05). In two (8.3%) treated patients with prolonged virus shedding, the oseltamivir resistance R292K mutation was revealed. In these patients, clonal analysis of the virus population showed the presence of additional oseltamivir-resistant mutants (E119V, N294S and deletion Del247–250). Conclusions Oseltamivir resistance is reported for the first time in A(H3N2) virus strains during the 2011–2012 influenza season. Different drug-resistant viruses emerged in hospitalized immunocompromised patients showing prolonged virus shedding.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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