Transmission and molecular characterisation of wild measles virus in Romania, 2008 to 2012.

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 from2008 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.

Ongoing rubella outbreak among adolescents in Salaj, Romania, September 2011-January 2012.

A rubella outbreak has been ongoing in Salaj, Romania since September 2011 involving 1,840 probable and confirmed cases among mainly unvaccinated adolescents. The index case had onset of illness on 6 September 2011. The highest number of cases was recorded among 10­14-year-olds and 15­19-year-olds. Complications were recorded for 11 cases and included meningitis and arthritis. Although the peak has passed, surveillance is being maintained in the region.

Ongoing measles outbreak in Romania, 2011.

Since January 2011 Romania has been experiencing a measles outbreak with 2,072 cases notified in 29 of the 42 Romanian districts. Most cases occurred in the north-western part of the country among unvaccinated children with the highest number of cases (893 cases) registered in children aged one to four years. This report underlines once more the need for additional measures targeting susceptible populations to achieve high vaccination coverage with two doses of measles-mumps-rubella vaccine.

Spotlight on measles 2010: An ongoing measles outbreak in the district of Neamt, Romania, August - September 2010.

We report an outbreak of measles that has been ongoing in the district of Neamt, Romania, since 22 August 2010. As of 21 September, 17 of 21 suspected cases have been laboratory-confirmed and there was one measles-related fatality.

"I-MOVE" towards monitoring seasonal and pandemic influenza vaccine effectiveness: lessons learnt from a pilot multi-centric case-control study in Europe, 2008-9.

Within I-MOVE (European programme to monitor seasonal and pandemic influenza vaccine effectiveness (IVE)) five countries conducted IVE pilot case-control studies in 2008-9. One hundred and sixty sentinel general practitioners (GP) swabbed all elderly consulting for influenza-like illness (ILI). Influenza confirmed cases were compared to influenza negative controls. We conducted a pooled analysis to obtain a summary IVE in the age group of >or=65 years. We measured IVE in each study and assessed heterogeneity between studies qualitatively and using the I2 index. We used a one-stage pooled model with study as a fixed effect. We adjusted estimates for age-group, sex, chronic diseases, smoking, functional status, previous influenza vaccinations and previous hospitalisations. The pooled analysis included 138 cases and 189 test-negative controls. There was no statistical heterogeneity (I2=0) between studies but ILI case definition, previous hospitalisations and functional status were slightly different. The adjusted IVE was 59.1% (95% CI: 15.3-80.3%). IVE was 65.4% (95% CI: 15.6-85.8%) in the 65-74, 59.6% (95% CI: -72.6 -90.6%) in the age group of >or=75 and 56.4% (95% CI: -0.2-81.3%) for A(H3). Pooled analysis is feasible among European studies. The variables definitions need further standardisation. Larger sample sizes are needed to achieve greater precision for subgroup analysis. For 2009-10, I-MOVE will extend the study to obtain early IVE estimates in groups targeted for pandemic H1N1 influenza vaccination.

Standardization of measles, mumps and rubella assays to enable comparisons of seroprevalence data across 21 European countries and Australia.

The aim of the European Sero-Epidemiology Network is to establish comparability of the serological surveillance of vaccine-preventable diseases in Europe. The designated reference laboratory (RL) for measles, mumps, rubella (MMR) prepared and tested a panel of 151 sera by the reference enzyme immunoassay (rEIA). Laboratories in 21 countries tested the panel for antibodies against MMR using their usual assay (a total of 16 different EIAs) and the results were plotted against the reference results in order to obtain equations for the standardization of national serum surveys. The RL also tested the panel by the plaque neutralization test (PNT). Large differences in qualitative results were found compared to the RL. Well-fitting standardization equations with R2> or =0.8 were obtained for almost all laboratories through regression of the quantitative results against those of the RL. When compared to PNT, the rEIA had a sensitivity of 95.3%, 92.8% and 100% and a specificity of 100%, 87.1% and 92.8% for measles, mumps and rubella, respectively. The need for standardization was highlighted by substantial inter-country differences. Standardization was successful and the selected standardization equations allowed the conversion of local serological results into common units and enabled direct comparison of seroprevalence data of the participating countries.

Molecular analysis of the first avian influenza H5N1 isolates from fowl in Romania.

Since the events of avian influenza (AI) caused by H5N1 subtype from Hong Kong (1997), the people worldwide have been confronted with new waves of epizootic influenza. In 2005 in Romania an unprecedent H5N1 epizootic occurred in domestic and wild birds. Therefore an immediate investigation by molecular approach of this highly pathogenic H5N1 strain was necessary. The virus isolation and the RNA extraction were performed in the Institute of Diagnosis and Animal Health while PCR and sequencing were carried out in Cantacuzino Institute. Herein we report the first evidence of H5N1 presence in Romanian fowls. The phylogenetic analysis of haemagglutinin and neuraminidase gene indicated a close relationship of Romanian strains to those from Siberia and China. The virological and molecular analysis of the first strains of avian virus from Romania confirmed the presence of H5N1 subtype, belonging to the genetic line Z. These results indicate that the avian virus from this genetic line is directly derived from the highly pathogenic viruses isolated in China and Russia in 2005.

A large rubella outbreak, Romania--2003.

Romania experienced a large rubella outbreak in 2002-03, with more than 115,000 reported cases nationwide, and an incidence of 531 reported cases per 100,000 population. The incidence was highest in children of school age. The cohorts of adolescent girls vaccinated in 1998 and 2002 (when a rubella-containing vaccine was available) had significantly lower incidence rates (p<0.001) compared with those in boys in the same age groups who were not vaccinated. In 2003, of the 150 suspected congenital rubella syndrome (CRS) cases reported, seven (4.6%) were confirmed by positive rubella IgM antibodies. In the absence of available rubella containing vaccine for outbreak control, an outbreak response plan to improve the detection of cases and to limit rubella virus transmission was developed. The following activities were conducted: surveillance of pregnant women with suspected rubella or history of exposure to rubella virus was implemented, with follow up of pregnancy outcomes; surveillance for CRS was strengthened; existing infection control guidelines to prevent disease transmission within healthcare facilities were reinforced; and a communication plan was developed. In May 2004, Romania is introducing measles, mumps and rubella (MMR) vaccine for routine vaccination of children aged 12 to 15 months, while continuing vaccination of girls in the 8th grade of school (13-14 years of age) with rubella-only vaccine.

The response in hemagglutinoinhibiting antibodies following influenza vaccination of HIV-infected children.

The study investigated the response in hemagglutinoinhibiting antibodies (HI) induced by the purified inactivated trivalent influenza vaccine prepared for the epidemic season 1996-1997, administered to a group of 24 human immunodeficiency virus (HIV)-infected children as compared to a group of HIV seronegative controls. The titres of serum HI antibodies were determined before and 30 days after vaccination. The evolution of the immune response in HIV seropositive children showed significant increases against all the antigenic components of influenza vaccine both as concerning the geometrical mean titres of HI antibodies and the protection rate (titres > or = 1:40). However, the amplitude of the immune response reported in the HIV seropositive group was lower, but insignificantly as compared to the HIV seronegative control group. No association between the individual response in HI antibodies and the determined amount of CD4' T lymphocytes was noticed.

Viral etiology of acute respiratory infections in infants and young children.

114 children with acute respiratory infections were investigated to detect the viral etiological agents. The following methods were used: the direct immunofluorescence technique for the rapid diagnosis from tracheobronchial aspirates and the serological reactions--hemaglutinoinhibition and complement fixation reaction--to determine the increase of antibodies titres. Of 55.2% respiratory infections with a viral etiology, 60.3% represent acute infections of the lower respiratory tract. Due to the influenza epidemic reported between October 1996 and February 1997 (with a higher number of cases than in the last 5 years), most viral respiratory infections were caused by influenza viruses (57.14%). The direct immunofluorescence technique proved to be sensitive and specific in detecting the viral etiological agents which caused respiratory infections. Thus, using this technique, a positive diagnosis was made in 68.2% of cases, of which 49.2% were positive by the hemagglutination and complement fixation reactions, too. The test specificity could have been higher if the pathological products had been prelevated within the first three days after the onset of the disease.

[ELISA in the rapid diagnosis of influenza using as the detecting antibodies polyclonal antinucleoprotein sera]. / ELISA in diagnosticul rapid al gripei utilizând ca anticorpi detectori seruri policlonale antinucleoproteina.

Hyperimmune polyclonal sera were obtained in order to use them as capture and detecting antibodies in rapid diagnostic of influenza A and B viruses by ELISA. The test shown 100% specificity. The sensitivity in directly detection of influenza viruses in human samples compared of influenza isolations was 49,25% for type A and 53,33% for type B. The sensitivity was increased after 48 hours from inoculation of human samples in cell culture-86,75% for type A detection and 80,0% for type B detection from supernatant mammalian tissue culture (MDCK).

[False-positive ELISA reactions for the hepatitis C virus and the human immunodeficiency virus after anti-influenzal vaccination]. / Reactii ELISA fals pozitive fata de virusul hepatitei C si virusul imunodeficientei umane dupa vaccinarea antigripala.

Possible appearance of ELISA false-positive results for hepatitis C virus (HCV) and human immunodeficiency virus (HIV) after vaccination against influenza was studied on 402 volunteers before, and 30 and 90 days after that. Our results prove that influenza vaccine can sometimes induce false-positive ELISA for HCV, but not for HIV. Their frequency is relatively small--0.96% in 10-20-years-old group and 3.1% in over 60 years age, while in 3-6 years age there were not registered this kind of reactions. The surveillance of individual ELISA-positive cases over time proves that cross-reacting antibodies HCV raised after vaccination against influenza are present only in second sera, that means 30 days after vaccination, but these antibodies disappeared 90 days later.

Seroepidemiological study of the circulation of influenza C virus in man.

The seroepidemiological study of the circulation of influenza C virus was achieved by testing HI antibodies in human sera collected from healthy subjects in Bucharest belonging to various age groups. The investigations were carried out over a two years period (October 1988--September 1990), using 3 influenza C virus strains: C/Taylor/1233/47, C/USSR/0303/77 and C/Moscow/1/84, the last two being antigenically similar. The analysis of the distribution of HI antibody values against the three influenza C virus strains showed that over October 1988--June 1989 the reported circulating viruses belonged to two distinct antigenic groups, one similar to the prototype C/Taylor/47 strains and the other to C/USSR/and/C/Moscow strains, whilst during the July 1989--September 1990 time interval viruses belonging solely to the C/USSR and C/Moscow antigenic group circulated. Similarly, one should note that circulation of influenza C viruses is not seasonal, it can appear anytime and even several times per year; this accounts for the relatively high and permanent antibody level in the population belonging to all age groups.

Comparative study of the immunogenicity of aqueous versus aluminium phosphate adsorbed split influenza vaccine C.I.

The antibody responses induced by the split influenza vaccine adsorbed on aluminium phosphate and the corresponding, nonadsorbed vaccine, both prepared in the Cantacuzino Institute, were studied in subjects belonging to three different age groups: 3-6, 10-15 and over 60 years of age, respectively. In all age groups the immunogenicity of the two vaccine preparations was similar, being uninfluenced by the level of preexisting antibodies. The immunogenicity of both vaccines was similar even in children considered to be non-primed. There were no differences in the persistence and specificity of antibodies induced by the two vaccines. No significant enhancement of the immunogenicity by aluminium phosphate was observed.