Large-scale hepatitis E virus genotype 3 outbreak on new caledonia island.

BACKGROUND AND AIM: Several symptomatic cases of hepatitis E virus (HEV) infections were reported to the New Caledonia Island Public Health Service between August and December 2023. This prompted epidemiological and virological investigations to identify the source of infection. APPROACH AND RESULTS: HEV RNA was assessed in symptomatic patients, various food items and pig farms on the island. HEV strains were characterised by sequencing. A seroprevalence study was also conducted on asymptomatic blood donors before and after the outbreak. 127 symptomatic cases were reported. Hospitalisation was required for 29/127 patients (22.8%). Hospitalised patients presented more frequently with comorbidities including liver and cardiovascular diseases, (80.7% vs. 27%, p<0.01) and 3 persons died (2.3%). Among the 100 HEV RNA-positive samples received at the French National Refence Centre for HEV, viral sequencing was possible for 76 samples. All strains were identified as HEV genotype 3 and 74/76 strains were grouped together (nucleotide identity: 98-100%). Full-length sequencing indicated a new HEV-3 subtype within HEV-3 subclade abk. Only genotype 3f strains were detected on the island's pig farms. No food items tested positive for HEV RNA. The seroprevalence of HEV IgG and IgM in blood donors was 9.2% (9/98) and 0%, respectively, in 2020, rising to 17.3% (17/98) and 2% (2/98) in 2024. CONCLUSIONS: Although all previous large-scale epidemics in Asia and Africa were associated with HEV-1 or 2, the New Caledonia outbreak was linked to HEV-3. A high number of symptomatic cases were admitted to hospital with a case fatality rate of 2.3%.

Respiratory virus detection in returning travelers and pilgrims from the Middle East.

BACKGROUND: Pilgrims travelling to Saudi Arabia are commonly infected with respiratory viruses. Since the Middle East Respiratory Syndrome Coronavirus (MERS-CoV) emerged in 2012, patients with acute respiratory symptoms returning from an endemic area can be suspected to be infected by this virus. METHODS: 98 patients suspected to have MERS-CoV infection from 2014 to 2019 were included in this retrospective cohort study. Upper and lower respiratory tract samples were tested by real-time RT-PCR for the detection of MERS-CoV and other respiratory viruses. Routine microbiological analyses were also performed. Patient data were retrieved from laboratory and hospital databases retrospectively. RESULTS: All patients with suspected MERS-CoV infection travelled before their hospitalization. Most frequent symptoms were cough (94.4%) and fever (69.4%). 98 specimens were tested for MERS-CoV RNA and none of them was positive. Most frequently detected viruses were Enterovirus/Rhinovirus (40/83; 48.2%), Influenzavirus A (34/90; 37.8%) and B (11/90; 12.2%), H-CoV (229E and OC43 10/83; 12% and 7/83; 8.4%, respectively). CONCLUSION: From 2014 to 2019, none of 98 patients returning from endemic areas was MERS-CoV infected. However, infections with other respiratory viruses were frequent, especially with Enterovirus/Rhinoviruses and Influenzaviruses.

Combating coxsackievirus B infections.

Coxsackieviruses B (CVB) are small, non-enveloped, single-stranded RNA viruses belonging to the Enterovirus genus of the Picornaviridae family. They are common worldwide and cause a wide variety of human diseases ranging from those having relatively mild symptoms to severe acute and chronic pathologies such as cardiomyopathy and type 1 diabetes. The development of safe and effective strategies to combat these viruses remains a challenge. The present review outlines current approaches to control CVB infections and associated diseases. Various drugs targeting viral or host proteins involved in viral replication as well as vaccines have been developed and shown potential to prevent or combat CVB infections in vitro and in vivo in animal models. Repurposed drugs and alternative strategies targeting miRNAs or based on plant extracts and probiotics and their derivatives have also shown antiviral effects against CVB. In addition, clinical trials with vaccines and drugs are underway and offer hope for the prevention or treatment of CVB-induced diseases.

[Coxsackievirus B infection and pathogenesis of type 1 diabetes]. / Infection à coxsackievirus B et pathogenèse du diabète de type 1.

Epidemiological and experimental studies suggest that enteroviruses (EV) and particularly coxsackieviruses B (CVB) are likely to trigger or accelerate the onset of islet autoimmunity and the development of type 1 diabetes (T1D) in genetically susceptible individuals. Several mutually non-exclusive mechanisms have been proposed to explain the involvement of CVB in the pathogenesis of T1D. CVB can infect and persist in the intestine, thymic cells, monocytes/macrophages, ductal cells and pancreatic ß-cells, which leads to structural or functional alterations of these cells. A chronic inflammatory response and disruption of tolerance towards ß-cells due to CVB infections are able to promote the recruitment and activation of pre-existing autoreactive T-cells and the destruction of ß-cells. Vaccine or therapeutic strategies to control EV infections have been developed and open perspectives for the prevention or treatment of T1D.

Fighting Enteroviral Infections to Prevent Type 1 Diabetes.

Enteroviruses (EVs), especially coxsackieviruses B (CVB), are believed to trigger or accelerate islet autoimmunity in genetically susceptible individuals that results in type 1 diabetes (T1D). Therefore, strategies are needed to fight against EV infections. There are no approved antiviral drugs currently available, but various antiviral drugs targeting viral or host cell proteins and vaccines have recently shown potential to combat CVB infections and may be used as new therapeutic strategies to prevent or reduce the risk of T1D and/or preserve ß-cell function among patients with islet autoantibodies or T1D.