Anabel Negredo

Increase in viral gastroenteritis outbreaks in Europe and epidemic spread of new norovirus variant

BACKGROUND Highly publicised outbreaks of norovirus gastroenteritis in hospitals in the UK and Ireland and cruise ships in the USA sparked speculation about whether this reported activity was unusual. METHODS We analysed data collected through a collaborative research and surveillance network of viral gastroenteritis in ten European countries (England and Wales were analysed as one region). We compiled data on total number of outbreaks by month, and compared genetic sequences from the isolated viruses. Data were compared with historic data from a systematic retrospective review of surveillance systems and with a central database of viral sequences. FINDINGS Three regions (England and Wales, Germany, and the Netherlands) had sustained epidemiological and viral characterisation data from 1995 to 2002. In all three, we noted a striking increase in norovirus outbreaks in 2002 that coincided with the detection and emergence of a new predominant norovirus variant of genogroup II4, which had a consistent mutation in the polymerase gene. Eight of nine regions had an annual peak in 2002 and the new genogroup II4 variant was detected in nine countries. Also, the detection of the new variant preceded an atypical spring and summer peak of outbreaks in three countries. INTERPRETATION Our data from ten European countries show a striking increase and unusual seasonal pattern of norovirus gastroenteritis in 2002 that occurred concurrently with the emergence of a novel genetic variant. In addition to showing the added value of an international network for viral gastroenteritis outbreaks, these observations raise questions about the biological properties of the variant and the mechanisms for its rapid dissemination.

Viral infections of the central nervous system in Spain: A prospective study

The aim of the study was to determine the incidence of viruses causing aseptic meningitis, meningoencephalitis, and encephalitis in Spain. This was a prospective study, in collaboration with 17 Spanish hospitals, including 581 cases (CSF from all and sera from 280): meningitis (340), meningoencephalitis (91), encephalitis (76), febrile syndrome (7), other neurological disorders (32), and 35 cases without clinical information. CSF were assayed by PCR for enterovirus (EV), herpesvirus (herpes simplex [HSV], varicella‐zoster [VZV], cytomegalovirus [CMV], Epstein–Barr [EBV], and human herpes virus‐6 [HHV‐6]), mumps (MV), Toscana virus (TOSV), adenovirus (HAdV), lymphocytic choriomeningitis virus (LCMV), West Nile virus (WNV), and rabies. Serology was undertaken when methodology was available. Amongst meningitis cases, 57.1% were characterized; EV was the most frequent (76.8%), followed by VZV (10.3%) and HSV (3.1%; HSV‐1: 1.6%; HSV‐2: 1.0%, HSV non‐typed: 0.5%). Cases due to CMV, EBV, HHV‐6, MV, TOSV, HAdV, and LCMV were also detected. For meningoencephalitis, 40.7% of cases were diagnosed, HSV‐1 (43.2%) and VZV (27.0%) being the most frequent agents, while cases associated with HSV‐2, EV, CMV, MV, and LCMV were also detected. For encephalitis, 27.6% of cases were caused by HSV‐1 (71.4%), VZV (19.1%), or EV (9.5%). Other positive neurological syndromes included cerebellitis (EV and HAdV), seizures (HSV), demyelinating disease (HSV‐1 and HHV‐6), myelopathy (VZV), and polyradiculoneuritis (HSV). No rabies or WNV cases were identified. EVs are the most frequent cause of meningitis, as is HSV for meningoencephalitis and encephalitis. A significant number of cases (42.9% meningitis, 59.3% meningoencephalitis, 72.4% encephalitis) still have no etiological diagnosis. J. Med. Virol. 85:554–562, 2013.

Acute respiratory distress syndrome after convalescent plasma use: treatment of a patient with Ebola virus disease contracted in Madrid, Spain

BACKGROUND In the current epidemic of Ebola virus disease, health-care workers have been transferred to Europe and the USA for optimised supportive care and experimental treatments. We describe the clinical course of the first case of Ebola virus disease contracted outside of Africa, in Madrid, Spain. METHODS Herein we report clinical, laboratory, and virological findings of the treatment of a female nurse assistant aged 44 years who was infected with Ebola virus around Sept 25-26, 2014, while caring for a Spanish missionary with confirmed Ebola virus disease who had been medically evacuated from Sierra Leone to La Paz-Carlos III University Hospital, Madrid. We also describe the use of experimental treatments for Ebola virus disease in this patient. FINDINGS The patient was symptomatic for 1 week before first hospital admission on Oct 6, 2014. We used supportive treatment with intravenous fluids, broad-spectrum antibiotics, and experimental treatments with convalescent plasma from two survivors of Ebola virus disease and high-dose favipiravir. On day 10 of illness, she had acute respiratory distress syndrome, possibly caused by transfusion-related acute lung injury, which was managed without mechanical ventilation. Discharge was delayed because of the detection of viral RNA in several bodily fluids despite clearance of viraemia. The patient was discharged on day 34 of illness. At the time of discharge, the patient had possible subacute post-viral thyroiditis. None of the people who had contact with the patient before and after admission became infected with Ebola virus. INTERPRETATION This report emphasises the uncertainties about the efficacy of experimental treatments for Ebola virus disease. Clinicians should be aware of the possibility of transfusion-related acute lung injury when using convalescent plasma for the treatment of Ebola virus disease. FUNDING La Paz-Carlos III University Hospital.

Unique human immune signature of Ebola virus disease in Guinea

Despite the magnitude of the Ebola virus disease (EVD) outbreak in West Africa, there is still a fundamental lack of knowledge about the pathophysiology of EVD. In particular, very little is known about human immune responses to Ebola virus. Here we evaluate the physiology of the human T cell immune response in EVD patients at the time of admission to the Ebola Treatment Center in Guinea, and longitudinally until discharge or death. Through the use of multiparametric flow cytometry established by the European Mobile Laboratory in the field, we identify an immune signature that is unique in EVD fatalities. Fatal EVD was characterized by a high percentage of CD4+ and CD8+ T cells expressing the inhibitory molecules CTLA-4 and PD-1, which correlated with elevated inflammatory markers and high virus load. Conversely, surviving individuals showed significantly lower expression of CTLA-4 and PD-1 as well as lower inflammation, despite comparable overall T cell activation. Concomitant with virus clearance, survivors mounted a robust Ebola-virus-specific T cell response. Our findings suggest that dysregulation of the T cell response is a key component of EVD pathophysiology.

Autochthonous Crimean-Congo Hemorrhagic Fever in Spain.

Crimean-Congo hemorrhagic fever (CCHF) is a widely distributed, viral, tickborne disease. In Europe, cases have been reported only in the southeastern part of the continent. We report two autochthonous cases in Spain. The index patient acquired the disease through a tick bite in the province of Ávila - 300 km away from the province of Cáceres, where viral RNA from ticks was amplified in 2010. The second patient was a nurse who became infected while caring for the index patient. Both were infected with the African 3 lineage of this virus. (Funded by Red de Investigación Cooperativa en Enfermedades Tropicales [RICET] and Efficient Response to Highly Dangerous and Emerging Pathogens at EU [European Union] Level [EMERGE].).

Chikungunya virus infections among travellers returning to Spain, 2008 to 2014.

Since the first documented autochthonous transmission of chikungunya virus in the Caribbean island of Saint Martin in 2013, the infection has been reported within the Caribbean region as well as North, Central and South America. The risk of autochthonous transmission of chikungunya virus becoming established in Spain may be elevated due to the large numbers of travellers returning to Spain from countries affected by the 2013 epidemic in the Caribbean and South America, as well as the existence of the Aedes albopictus vector in certain parts of Spain. We retrospectively analysed the laboratory diagnostic database of the National Centre for Microbiology, Institute of Health Carlos III (CNM-ISCIII) from 2008 to 2014. During the study period, 264 confirmed cases, of 1,371 suspected cases, were diagnosed at the CNM-ISCIII. In 2014 alone, there were 234 confirmed cases. The highest number of confirmed cases were reported from the Dominican Republic (n = 136), Venezuela (n = 30) and Haiti (n = 11). Six cases were viraemic in areas of Spain where the vector is present. This report highlights the need for integrated active case and vector surveillance in Spain and other parts of Europe where chikungunya virus may be introduced by returning travellers.

Phylogenetic Characterization of Crimean-Congo Hemorrhagic Fever Virus, Spain

Two cases of Crimean-Congo hemorrhagic fever were reported in Spain during 2016. We obtained the virus from a patient sample and characterized its full genomic sequence. Phylogenetic analysis indicated that the virus corresponds to the African genotype III, which includes viruses previously found in West and South Africa.

Ribavirin Had Demonstrable Effects on the Crimean-Congo Hemorrhagic Fever Virus (CCHFV) Population and Load in a Patient With CCHF Infection

The use of ribavirin to treat Crimean-Congo hemorrhagic fever virus (CCHFV) infection has been controversial, based on uncertainties about its antiviral efficacy in clinical case studies. We studied the effect of ribavirin treatment on viral populations in a recent case by deep-sequencing analysis of plasma samples obtained from a CCHFV-infected patient before, during, and after a 5-day regimen of ribavirin treatment. The CCHFV load dropped during ribavirin treatment, and subclonal diversity (transitions) and indels increased in viral genomes during treatment. Although the results are based on a single case, these data demonstrate the mutagenic effect of ribavirin on CCHFV in vivo.