GloPID-R report on chikungunya, o'nyong-nyong and Mayaro virus, part 2: Epidemiological distribution of o'nyong-nyong virus.

The GloPID-R (Global Research Collaboration for Infectious Disease Preparedness) chikungunya (CHIKV), o'nyong-nyong (ONNV) and Mayaro virus (MAYV) Working Group has been established to identify gaps of knowledge about the natural history, epidemiology and medical management of infection by these viruses, and to provide adapted recommendations for future investigations. Here, we present a report dedicated to ONNV epidemiological distribution. Two large-scale ONNV outbreaks have been identified in Africa in the last 60 years, interspersed with sporadic serosurveys and case reports of returning travelers. The assessment of the real scale of ONNV circulation in Africa remains a difficult task and surveillance studies are necessary to fill this gap. The identification of ONNV etiology is made complicated by the absence of multiplex tools in co-circulation areas and that of reference standards, as well as the high cross-reactivity with related pathogens observed in serological tests, in particular with CHIKV. This is a specific obstacle for seroprevalence studies, that necessitate an improvement of serological tools to provide robust results. The scarcity of existent genetic data currently limits molecular epidemiology studies. ONNV epidemiology would also benefit from reinforced entomological and environmental surveillance. Finally, the natural history of the disease deserves to be further investigated, with a specific attention paid to long-term complications. Considering our incomplete knowledge on ONNV distribution, GloPID-R CHIKV, ONNV and MAYV experts recommend that a major effort should be done to fill existing gaps.

Risk factors of exposure to Aedes albopictus bites in mainland France using an immunological biomarker.

In recent decades, the invasive Aedes albopictus vector has spread across Europe and is responsible for numerous outbreaks of autochthonous arboviral disease. The aim of this study was to identify epidemiological and sociological risk factors related to individual levels of exposure to Aedes albopictus bites. A multidisciplinary survey was conducted with volunteer blood donors living in areas either colonised or not by Aedes albopictus in mainland France. Individual levels of exposure were evaluated by measuring the IgG level specific to Aedes albopictus saliva. The most striking risk factors concerned the localisation and characteristics of the dwelling. Individuals living in areas colonised prior to 2009 or recently colonised (between 2010 and 2012) had higher anti-salivary gland extract IgG levels compared with those who were living in areas not yet colonised by Ae. albopictus. The type of dwelling did not seem to impact the level of exposure to Aedes bites. People living in apartments had a higher anti-salivary gland extract IgG level than those living in individual houses but the difference was not statistically significant. Interestingly, the presence of air conditioning or window nets was associated with a noticeable reduction in bite intensity.

Measles and rubella seroprevalence in a population of young adult blood donors, France 2013.

As part of the evaluation of the French plan for the elimination of measles and rubella, we conducted a seroprevalence survey in 2013, aimed at updating seroprevalence data for people 18-32 years old. A secondary objective was to estimate measles incidence in this population during the 2009-2011 outbreak, and thus estimate the exhaustiveness of measles mandatory reporting. We used a cross-sectional survey design, targeting blood donors 18-32 years old, living in France since 2009, who came to give blood in a blood collecting site. We included 4647 people in metropolitan France, 806 people in Réunion Island and 496 in the French Caribbean. A further 3942 individuals were interviewed in the south-east region of metropolitan France to estimate the exhaustiveness of measles mandatory reporting. One of the main findings of this survey is that the proportion of people 18-32 years old susceptible to both measles and rubella infections remained high in France in 2013, 9.2% and 5.4%, respectively, in metropolitan France, even after the promotion campaigns about vaccination catch-up during and following the major measles epidemic in 2009-2011. Applying our results to French census data would suggest that around 1 million people aged 18-32 years old are currently susceptible to measles in France, despite this age group being one of the vaccination targets of the national measles elimination plan. Another important finding is that only an estimated 45% of the true number of cases in this age group was actually notified, despite notification being mandatory.

GloPID-R report on Chikungunya, O'nyong-nyong and Mayaro virus, part I: Biological diagnostics.

The GloPID-R (Global Research Collaboration for Infectious Disease Preparedness) Chikungunya (CHIKV), O'nyong-nyong (ONNV) and Mayaro virus (MAYV) Working Group is investigating the natural history, epidemiology and medical management of infection by these viruses, to identify knowledge gaps and to propose recommendations for direct future investigations and rectification measures. Here, we present the first report dedicated to diagnostic aspects of CHIKV, ONNV and MAYV. Regarding diagnosis of the disease at the acute phase, molecular assays previously described for the three viruses require further evaluation, standardized protocols and the availability of international standards representing the genetic diversity of the viruses. Detection of specific IgM would benefit from further investigations to clarify the extent of cross-reactivity among the three viruses, the sensitivity of the assays, and the possible interfering role of cryoglobulinaemia. Implementation of reference panels and external quality assessments for both molecular and serological assays is necessary. Regarding sero-epidemiological studies, there is no reported high-throughput assay that can distinguish among these different viruses in areas of potential co-circulation. New specific tools and/or improved standardized protocols are needed to enable large-scale epidemiological studies of public health relevance to be performed. Considering the high risk of future CHIKV, MAYV and ONNV outbreaks, the Working Group recommends that a major investigation should be initiated to fill the existing diagnostic gaps.

Complete coding sequence of Zika virus from Martinique outbreak in 2015.

Zika virus is an Aedes-borne Flavivirus causing fever, arthralgia, myalgia rash, associated with Guillain-Barré syndrome and suspected to induce microcephaly in the fetus. We report here the complete coding sequence of the first characterized Caribbean Zika virus strain, isolated from a patient from Martinique in December, 2015.

[Hepatitis E virus: Blood transfusion implications]. / Virus de l'hépatite E, implications en transfusion sanguine.

Hepatitis E virus (HEV) is a non-enveloped RNA virus transmitted by the fecal-oral route. Autochthonous hepatitis E occurring in developed countries is caused by genotypes 3 and 4 and is a zoonotic infection. Humans are infected mostly after ingestion of undercooked meat from infected animals. Most HEV 3 and 4 infections are clinically inapparent. However, genotype 3 (HEV 3) can lead to chronic hepatitis in immuno-compromised patients such as organ-transplant recipients and patients with haematological malignancies. In Europe, HEV 3 is implicated in transfusion-transmitted HEV infection. In France, as observed in several European countries, prevalence of HEV RNA and specific IgG antibodies are high indicating that viral circulation is important. The systematic HEV NAT screening of blood donations used for preparation of solvent detergent plasma indicate that 1 to 2218 donation is infected by HEV RNA. The need or implementation's impacts of safety measures to prevent HEV transmission by blood transfusion are under reflexion by French's health authorities. The HEV NAT screening is the only available tool of prevention. Alternative strategies are under investigation including individual or mini pool NAT testing all or part of blood donations.

[Assessment of a transfusion emergent risk: the case of HEV]. / Estimation d'un risque transfusionnel émergent: l'exemple du VHE.

BACKGROUND: The risk assessment for blood transfusion is an essential step that must precede any screening strategy of a pathogen transmitted by transfusion. After several cases of HEV transmission by transfusion in France, a risk assessment for this virus was performed. METHODS: We used a method based on the prevalence of HEV-RNA in plasmas collected for the preparation of SD-plasma. To estimate the rate of HEV-RNA positive among all blood donations, data on SD-plasma were adjusted on the following HEV risk factors: gender, age group and region of residence. We assumed that HEV risk factors were the same in plasma donors and whole blood donors. RESULTS: Among 57,101 plasma donations tested for HEV-RNA in 2013, 24 were positive (crude rate of 4.2 per 10,000 donations). After adjustment, the total number of HEV-RNA positive blood donations was estimated at 788, accounting for a rate of 2.65 per 10,000 donations (95% CI: 1.6-3.7) or 1 in 3800 donations (1 in 6,200-1 in 2,700). This rate was 12 times higher in men than in women, increased with age, and varied according to region of residence. CONCLUSION: The risk of blood donation contamination by HEV has been estimated to be 1 in 3800 donations in 2013. An essential input is still missing to assess now the risk in recipients: the minimum infectious dose. Furthermore, the risk in recipients has to be analyzed according to characteristics of transfused patients: presence of anti-HEV immunity, existence of chronic liver disease or immunodeficiency.

Blood group typing in five Afghan populations in the North Hindu-Kush region: implications for blood transfusion practice.

BACKGROUND AND OBJECTIVES: Blood incompatibility arises from individual and ethnic differences in red blood cell (RBC) antigen profiles. This underlines the importance of documenting RBC antigen variability in various ethnic groups. Central Asia is an area with a long and complex migratory history. The purpose of this article is to describe key antigen frequencies of Afghan ethnic groups in the Hindu-Kush region of Afghanistan as a basis for improving blood transfusion practices in that area. MATERIALS AND METHODS: The key ABO, Rh and Kell antigens were investigated in five Afghan populations. In order to depict accurately the blood group gene diversity in the area, DNA from eight additional Pakistani populations were included, and the entire sample set screened using two multiplex polymerase chain reactions sensitive for 17 alleles in 10 blood group genetic systems (MNS, Kell, Duffy, Kidd, Cartwright, Dombrock, Indian, Colton, Diego and Landsteiner-Wiener). RESULTS: Phenotype and allele frequencies fell within the ranges observed in Western European and East Asian populations. Occurrence of DI*01, IN*01, LW*07 and FY*02N.01 and prevalence of ABO*B were consistent with migratory history as well as with putative environmental adaptation in the subtropical environment Hindu-Kush region. CONCLUSION: These findings expand the current knowledge about key antigen frequencies. Regarding occurrence of viral markers, further blood transfusion in the region requires rigorous typing.

Multicentric evaluation of the DiaMed enzyme-linked immunosorbent assay malaria antibody test for screening of blood donors for malaria.

BACKGROUND: The risk of malaria transmission by blood transfusion is critical due to extensive travel from endemic areas to non-endemic areas. An enzyme-linked immunosorbent assay (ELISA) malaria antibody test has been developed that is claimed to perform better than the immunofluorescence assay test (IFAT). The assay contains antigens to both Plasmodium falciparum and Plasmodium vivax. A multicentre study was performed to evaluate the appropriateness of replacing the IFAT by the new ELISA test. MATERIAL AND METHODS: Nine French blood banks participated in this multicentre study. Two panels of samples were evaluated. The first included 4163 samples from healthy donors and was used to calculate clinical specificity of the assay. The second involved 10,995 samples, either collected retrospectively or prospectively from malaria-risk donors , was used to assess the comparative performance of the ELISA and IFAT. Discordant samples were further tested using an in-house IFAT and also tested for presence of Plasmodium DNA by polymerase chain reaction. RESULTS: The ELISA showed a clinical specificity of 99.02%. In the malaria-risk blood donors groups, the retrospective group showed a concordance rate of 92.6% (k = 0.90), while the prospective group showed a concordance rate of 97% (k = 0.46). After confirming the discordant sample results by an in-house IFAT, the k index increased to 0.81. None of the discordant samples was shown to contain Plasmodium DNA. CONCLUSION: The performance of the ELISA test in this study has confirmed its potential as a new screening test for use in blood banks, as an alternative to the IFAT in prevention of transfusion-transmitted malaria in non-endemic countries.

Inactivation of a European strain of West Nile virus in single- donor platelet concentrate using the INTERCEPT blood system.

BACKGROUND AND OBJECTIVE: In order to prevent West Nile virus (WNV) contaminations by transfusion, the French National Blood Service decided to evaluate the INTERCEPT Blood System's efficiency on a European strain. MATERIALS AND METHODS: Culture supernatant of WNV was used to infect six platelets concentrates. Viral titre was determined by plaque reduction neutralization test before and after viral inactivation using the INTERCEPT Blood System. RESULTS: In all assays, the absence of plaque forming unit was observed after viral inactivation. The log reduction observed ranged between > 5.1 logs to > 5.2 logs. CONCLUSION: INTERCEPT Blood System is a commercially viral inactivation method potentially useful in order to prevent WNV transmission by blood products in France during re-emerging outbreaks.

[West Nile virus (WNV): generalities and implications for blood transfusion]. / Le virus West Nile: généralités et implications en transfusion sanguine.

West Nile virus (WNV) is an arbovirus (genus Flavivirus, Family Flaviviridae, transmitted to humans by mosquito bite. In most cases (80%), human infection remains asymptomatic. Severe central nervous system complications (encephalitis and meningoencephalitis) are rare. In the Old World, the virus circulation has been demonstrated in Asia, Australia, Africa, Middle East and Europe. Several outbreaks in humans have been described. Following its introduction into North America in 1999, WN virus has been responsible of a large number of human cases in USA and Canada. For the first time, viral transmission by blood products was clearly demonstrated in USA in 2002. In France, the presence of virus has been reported in the Southeastern departments since 1962. In 2003, the occurrence of humans cases at specific geographical foci urged the French National Blood Agency (etablissement francais du sang) to take preventive measures for evaluating the virus transmission risks.

Evolutionary relationship between Old World West Nile virus strains. Evidence for viral gene flow between Africa, the Middle East, and Europe.

Little is known about the genetic relationships between European and other Old-World strains of West Nile virus (WNV) and persistence of WNV North of Mediterranean. We characterized the complete genomes of three WNV strains from France (horse-2000), Tunisia (human-1997) and Kenya (mosquito-1998), and the envelope, NS3 and NS5 genes of the Koutango virus. Phylogenetic analyses including all available full-length sequences showed that: (1) Koutango virus is a distant variant of WNV; (2) the three characterized strains belong to lineage 1, clade 1a; (3) the Tunisian strain roots the lineage of viruses introduced in North America. We established that currently available partial envelope sequences do not generate reliable phylogenies. Accordingly, establishing a large WNV sequence database is pivotal for the understanding of spatial and temporal epidemiology of this virus. For rapid completion of that purpose, colinearized E-NS3-NS5 gene sequences were shown to constitute a valuable surrogate for complete sequences.