Eurosurveillance - Volume 18, Issue 50, 12 December 2013

In October 2013, autochthonous dengue fever was diagnosed in a laboratory technician in Bouches-du-Rhône, southern France, a department colonised by Aedes albopictus since 2010. After ruling out occupational contamination, we identified the likely chain of local vector-borne transmission from which the autochthonous case arose. Though limited, this second occurrence of autochthonous dengue transmission in France highlights that efforts should be continued to rapidly detect dengue virus introduction and prevent its further dissemination in France. .

We report six confirmed cases of Legionnaires' disease in Scotland caused by Legionella longbeachae serogroup 1, identified over a four-week period in August-September 2013. All cases required admission to hospital intensive care facilities. All cases were amateur gardeners with frequent exposure to horticultural growing media throughout their incubation period. L. longbeachae was identified in five samples of growing media linked to five cases. Product tracing did not identify a common product or manufacturer. .

Between June and September 2013, sera from 11 dromedary camels, 150 goats, 126 sheep and 91 cows were collected in Jordan, where the first human Middle-East respiratory syndrome (MERS) cluster appeared in 2012. All sera were tested for MERS-coronavirus (MERS-CoV) specific antibodies by protein microarray with confirmation by virus neutralisation. Neutralising antibodies were found in all camel sera while sera from goats and cattle tested negative. Although six sheep sera reacted with MERS-CoV antigen, neutralising antibodies were not detected.

In Saudi Arabia, including regions of Riyadh and Al Ahsa, pseudoparticle neutralisation (ppNT) and microneutralisation (MNT) tests detected no antibodies to Middle East Respiratory Syndrome coronavirus (MERS-CoV) in sheep (n= 100), goats (n= 45), cattle (n= 50) and chickens (n= 240). Dromedary camels however, had a high prevalence of MERS-CoV antibodies. Bovine coronavirus (BCoV) infected sera from cattle had no cross-reactivity in MERS-CoV ppNT or MNT, while many dromedary camels' sera reacted to both BCoV and MERS-CoV. Some nevertheless displayed specific serologic reaction profiles to MERS-CoV. .

Molecular characterisation of measles virus is a powerful tool for tracing transmission. Genotyping may prove the absence of endemic circulation of measles virus, i.e. transmission for more than 12 months, which is one of the criteria for verifying elimination of the disease. We have genetically characterised measles viruses detected in Romania from 2008 to 2012, focusing on the recent outbreaks from 2010 to 2012 that affected mainly groups with limited access to healthcare and schools. The findings emphasise the importance of genotyping during the different phases of an outbreak. A total of 8,170 cases were notified, and 5,093 (62%) of the 7,559 possible cases were serologically confirmed. RT-PCR was performed for 104 samples: from the 101 positive samples obtained from sporadic measles cases or clusters from different counties, 73 were genotyped. Sporadic measles cases associated with D4 and D5 viruses were observed from 2008 to 2009. Genotype D4-Manchester was predominant in 2011 and 2012. In addition, the related variant D4-Maramures and MVs/Limoges.FRA/17.10[D4] and a few D4-Hamburg strains were detected. The detection of several distinct MV-D4 genotypes suggests multiple virus importations to Romania. The outbreak associated with D4 genotype is the second largest outbreak in Romania in less than 10 years.

The novel avian influenza A(H7N9) infection has recently emerged to cause severe respiratory illness in China. The objectives of this study were to define the kinetics of the antibody responses in patients with influenza A(H7N9) disease and to correlate these kinetics with clinical outcome. Serial serum samples were obtained at intervals of three to four days from 18 patients with virologically confirmed A(H7N9) disease in Shanghai. We determined the kinetics of the haemagglutination inhibition (HI) and A(H7H9) pseudotype neutralisation antibody (Nab) responses and correlated these with clinical outcomes. Most patients had robust serological responses by both HI and Nab tests. Taking into account censoring due to time of testing and death, the median time from onset of illness to Nab titre ≥1:40 was 14 days (95% confidence interval (CI): 11-18 days) in the fatal cases and 10.5 days (95% CI: 7-12) in the survivors (p=0.003). The two groups did not differ in initial Nab titres, but the rate of increase in Nab titres was significantly faster for survivors by approximately 10-fold per 15 days (p=0.007). Early and rapid induction of Nab was correlated significantly with better clinical outcome. .

In several European countries, diagnosis of nephropathia epidemica, a mild form of haemorrhagic fever with renal syndrome (HFRS) caused by Puumala-virus infection, has increased over the past 10-20 years. In Switzerland, despite its geographical proximity to regions with epidemic outbreaks in Germany and France, infections are detected only sporadically. To estimate the actual prevalence and potential risk factors of human hantavirus infections in Switzerland, a seroepidemiological study was performed in 2009 on serum samples from 4,559 blood donors and 1,810 military personnel. Sera were screened using commercial Puumala IgG and hantavirus IgG enzyme-linked immunosorbent assays indicating a seroprevalence of 1% and 9%, respectively. Subsequently, the samples were analysed by immunofluorescence assay and immunoblot assay, showing a much lower prevalence, of 0.4% and 0.3%, respectively. Two of the serum samples achieved an 80% reduction in plaque-forming units in a neutralisation test. Statistical evaluation of questionnaires only identified an association of age (above 50 years) with hantavirus seropositivity when adjusted for sex (odds ratio: 2.36; 95% confidence interval: 1.10-5.05). This study provides baseline data (0.3-0.4%) for future monitoring of hantavirus seroprevalence in Switzerland and highlights the challenges in estimating the seroprevalence of these viruses in a country with very low endemicity. .