Eurosurveillance - Volume 14, Issue 32, 13 August 2009

Following the declaration by the World Health Organization (WHO) of human cases of infection with a new influenza A(H1N1)v virus of swine origin, the Turkish Ministry of Health launched a case-based reporting of influenza A(H1N1)v throughout the country on 27 April 2009. The index case was detected on 15 May 2009. As of 17 July 2009 the number of laboratory-confirmed cases of influenza A(H1N1)v totaled 128 of whom 38 were indigenous cases.

We present a preliminary analysis of 1,771 confirmed cases of influenza A(H1N1)v reported in Peru by 17 July including the frequency of the clinical characteristics, the spatial and age distribution of the cases and the estimate of the transmission potential. Age-specific frequency of cases was highest among school age children and young adults, with the lowest frequency of cases among seniors, a pattern that is consistent with reports from other countries. Estimates of the reproduction number lie in the range of 1.2 to 1.7, which is broadly consistent with previous estimates for this pandemic in other regions. Validation of these estimates will be possible as additional data become available.

For the next influenza season (winter 2009-10) the relative contributions to virus circulation and influenza-associated morbidity of the seasonal influenza viruses A(H3N2), A(H1N1) and B, and the new influenza A(H1N1)v are still unknown. We estimated the chances of seasonal influenza to circulate during the upcoming season using data of the German influenza sentinel scheme from 1992 to 2009. We calculated type and subtype-specific indices for past exposure and the corresponding morbidity indices for each season. For the upcoming season 2009-10 our model suggests that it is unlikely that influenza A(H3N2) will circulate with more than a low intensity, seasonal A(H1N1) with more than a low to moderate intensity, and influenza B with more than a low to median intensity. The probability of a competitive circulation of seasonal influenza A with the new A(H1N1)v is low, increasing the chance for the latter to dominate the next influenza season in Germany.

The May 2009 round of INSTAND's ring trial ""Chlamydia trachomatis detection PCR/NAT"" included a sample with high amount of the Swedish new variant of C. trachomatis (nvCT). A spectrum of at least 12 different commercial diagnostic nucleic acid amplification tests (NAATs) and many different in house NAATs were applied by the 128 participating laboratories which reported 152 results. Approximately 80% of the results correctly reported the presence of C. trachomatis in the nvCT specimen. The nvCT sample was mainly missed, as expected, by participants using the Roche COBAS Amplicor CT/NG (15.5% of reported results) but also by several participants using in house NAATs. The trend towards using nvCT-detecting NAATs is obvious and in addition to the new dual-target NAATs from Roche and Abbott, and BD ProbeTec ET, also a number of new CE mark-certified commercial tests from smaller diagnostic companies as well as many different in house NAATs were used. Laboratories using commercial or in house NAATs that do not detect the nvCT are encouraged to carefully monitor their C. trachomatis incidence, participate in appropriate external quality assurance and controls schemes, and consider altering their testing system. The reliable detection of low amounts of the wildtype C. trachomatis strain in other samples of the ring trial set indicates a good diagnostic performance of all applied commercial NAATs while also detecting the nvCT strain.

An outbreak of Escherichia coli O157 involving four people in North Wales is currently being investigated. Laboratory typing shows all the isolates belong to phage type 2. All four cases reported eating different products from a fast food outlet in the area. The possibility of other common exposures is being explored.

We describe a severe gastroenteritis with non-O1, non-O139 Vibrio cholerae in an immunocompromised patient returning from a holiday in Spain in July 2009. Predisposing factors and possible cholera enterotoxin production could explain the unusually grave symptomatology. The patient recovered after doxycyclin treatment.

The objective of this study was to investigate changes in the epidemiology of hepatitis B virus infection in the general population and selected groups of immigrants in the region of northeastern Greece over the last decade in relation to the introduction of hepatitis B vaccination programmes. Two population-based seroprevalence surveys were carried out during the years 1992-1994 and 1998-2006. In total, 25,105 individuals were tested for the presence of hepatitis B virus markers: HBsAg, anti-HBs and anti-HBc. Childhood/adolescence immunisation programmes began early in 1994 in selected groups of immigrants and were complemented by the national vaccination programme in 1998. Between 1992-1994 and 1998-2006, the HBsAg carrier rate declined from 5.4% [95% CI: 4.5-5.9] in adults (20-60 years old) and 1.9% [95% CI: 1.6-2.4] in children/adolescents (5-19 years old) of indigenous residents to 3.4% [95% CI: 2.9-3.8] and 0.6% [95% CI: 0.2-1.4] respectively (p<0.05). In spite of a decrease compared with 1992-1994, the percentage of HBsAg carriers was still relatively high in 1998-2006 among the Muslim religious minority group (8.2% [95% CI: 8.0-8.7] in adults and 2% [95% CI: 1.7-2.4] in children/adolescents) and in immigrants from the former Soviet Union (4.3% [95% CI: 3.6-4.7] in adults and 1.1% [95% CI: 0.8-2.4] in children/adolescents) (p<0.05 for both selected groups versus general population). The decline of the prevalence of HBsAg in the general population and selected groups of immigrants in northeastern Greece over the last decade supports the effectiveness of the ongoing immunisation programme although the information on the actual number of cases of acute HBV infection is not available.