[Mumps epidemic in vaccinated children in West Switzerland]

Since 1991, 6 years after the recommendation of universal childhood vaccination against measles, mumps, and rubella (MMR triple vaccine), Switzerland is confronted with a large number of mumps cases affecting both vaccinated and unvaccinated children. Up to 80% of the children suffering from mumps between 1991 and 1995 had previously been vaccinated, the majority with the Rubini vaccine strain. On the basis of a case-control study including 102 patients and 92 controls from the same pediatric population, a study of the humoral immune-response following vaccination with the Rubini vaccine in 6 young adult volunteers, and two different genetic studies, we investigated the complex problem of large scale vaccine failure in Switzerland. We conclude that the recently reported large number of Swiss mumps cases was caused by at least four interacting factors: 1. A vaccine coverage of 90-95% at the age of 2 years is necessary to interrupt mumps wild virus circulation. The nationwide vaccine coverage in Switzerland of some 80% in 27-36 month-old children is too low. 2. Primary vaccine failures (absence of seroconversion or unprotective low levels of neutralizing antibodies), as well as secondary vaccine failures due to the rapid decline of antibodies to mumps virus in our volunteers and controls, seem to be frequent after vaccination with the Rubini strain. 3. Despite its reported Swiss origin, the Rubini strain does not belong to the mumps virus lineages recently circulating in this area but is closely related to American mumps virus strains. 4. Differences in protein structure between the vaccine strain and the circulating wild type strains, and in particular a different neutralization epitope in the hemagglutinin neuraminidase protein, may additionally contribute to the lack of protection in vaccinated individuals.

Influenza-associated myositis in children

BACKGROUND: Influenza-associated myositis (IAM) is an infrequent and poorly known complication of influenza virus infection in children. The aim of this study was to describe five cases of IAM and to review the literature on IAM in children. PATIENTS AND METHODS: We conducted a retrospective analysis of cases of IAM diagnosed at two university children's hospitals in Switzerland during two consecutive influenza seasons. Findings were compared with 39 individual case reports and five publications summarizing an additional 272 cases identified by a medical online library (MEDLINE) search. RESULTS: Overall, 316 cases were analyzed. IAM typically occurred in school-aged children with a 2:1 male predominance. Influenza B and A viruses were identified in 76% and 24% of cases, respectively. The median interval between onset of influenza and onset of IAM was 3 days (range 0-18). The calf muscles were involved alone or together with other muscle groups in 69% and 31% of cases, respectively. Blood creatine phosphokinase (CPK) concentration was invariably elevated. Median duration to clinical recovery was 3 days (range 1-30). Rhabdomyolysis occurred in ten of 316 patients (3%), was more common in girls (80%), more often associated with influenza A (86%), and led to renal failure in eight patients (80%). CONCLUSION: Clinical and laboratory findings of IAM are highly characteristic and allow a rapid diagnosis during the influenza season.

Antigenic and genetic variations in European and North American equine influenza virus strains (H3N8) isolated from 2006 to 2007

Equine influenza virus (EIV) surveillance is important in the management of equine influenza. It provides data on circulating and newly emerging strains for vaccine strain selection. To this end, antigenic characterisation by haemaggluttination inhibition (HI) assay and phylogenetic analysis was carried out on 28 EIV strains isolated in North America and Europe during 2006 and 2007. In the UK, 20 viruses were isolated from 28 nasopharyngeal swabs that tested positive by enzyme-linked immunosorbent assay. All except two of the UK viruses were characterised as members of the Florida sublineage with similarity to A/eq/Newmarket/5/03 (clade 2). One isolate, A/eq/Cheshire/1/06, was characterised as an American lineage strain similar to viruses isolated up to 10 years earlier. A second isolate, A/eq/Lincolnshire/1/07 was characterised as a member of the Florida sublineage (clade 1) with similarity to A/eq/Wisconsin/03. Furthermore, A/eq/Lincolnshire/1/06 was a member of the Florida sublineage (clade 2) by haemagglutinin (HA) gene sequence, but appeared to be a member of the Eurasian lineage by the non-structural gene (NS) sequence suggesting that reassortment had occurred. A/eq/Switzerland/P112/07 was characterised as a member of the Eurasian lineage, the first time since 2005 that isolation of a virus from this lineage has been reported. Seven viruses from North America were classified as members of the Florida sublineage (clade 1), similar to A/eq/Wisconsin/03. In conclusion, a variety of antigenically distinct EIVs continue to circulate worldwide. Florida sublineage clade 1 viruses appear to predominate in North America, clade 2 viruses in Europe.

A systems analysis identifies a feedforward inflammatory circuit leading to lethal influenza infection

For acutely lethal influenza infections, the relative pathogenic contributions of direct viral damage to lung epithelium versus dysregulated immunity remain unresolved. Here, we take a top-down systems approach to this question. Multigene transcriptional signatures from infected lungs suggested that elevated activation of inflammatory signaling networks distinguished lethal from sublethal infections. Flow cytometry and gene expression analysis involving isolated cell subpopulations from infected lungs showed that neutrophil influx largely accounted for the predictive transcriptional signature. Automated imaging analysis, together with these gene expression and flow data, identified a chemokine-driven feedforward circuit involving proinflammatory neutrophils potently driven by poorly contained lethal viruses. Consistent with these data, attenuation, but not ablation, of the neutrophil-driven response increased survival without changing viral spread. These findings establish the primacy of damaging innate inflammation in at least some forms of influenza-induced lethality and provide a roadmap for the systematic dissection of infection-associated pathology.

Epidemic of Salmonellosis in Passerine Birds in Switzerland With Spillover to Domestic Cats

A die-off of passerine birds, mostly Eurasian siskins (Carduelis spinus), occurred in multiple areas of Switzerland between February and March 2010. Several of the dead birds were submitted for full necropsy. Bacteriological examination was carried out on multiple tissues of each bird. At gross examination, common findings were light-tan nodules, 1 to 4 mm in diameter, scattered through the esophagus/crop. Histologically, a necroulcerative transmural esophagitis/ingluvitis was observed. Bacterial cultures yielded Salmonella enterica subsp. enterica serovar Typhimurium. At the same time, 2 pet clinics reported an unusual increase of domestic cats presented with fever, anorexia, occasionally dolent abdomen, and history of presumed consumption of passerine birds. Analysis of rectal swabs revealed the presence of S. Typhimurium in all tested cats. PFGE (pulsed field electrophoresis) analysis was performed to characterize and compare the bacterial isolates, and it revealed an indistinguishable pattern between all the avian and all but 1 of the feline isolates. Cloacal swabs collected from clinically healthy migrating Eurasian siskins (during autumn 2010) did not yield S. Typhimurium. The histological and bacteriological findings were consistent with a systemic infection caused by S. Typhimurium. Isolation of the same serovar from the dead birds and ill cats, along with the overlapping results of the PFGE analysis for all the animal species, confirmed a spillover from birds to cats through predation. The sudden increase of the number of siskins over the Swiss territory and their persistency during the whole winter of 2009-2010 is considered the most likely predisposing factor for the onset of the epidemic.

Bovine Tuberculosis Risk Factors for British Herds Before and After the 2001 Foot-and-Mouth Epidemic: What have we Learned from the TB99 and CCS2005 Studies?

Over the last couple of decades, the UK experienced a substantial increase in the incidence and geographical spread of bovine tuberculosis (TB), in particular since the epidemic of foot-and-mouth disease (FMD) in 2001. The initiation of the Randomized Badger Culling Trial (RBCT) in 1998 in south-west England provided an opportunity for an in-depth collection of questionnaire data (covering farming practices, herd management and husbandry, trading and wildlife activity) from herds having experienced a TB breakdown between 1998 and early 2006 and randomly selected control herds, both within and outside the RBCT (the so-called TB99 and CCS2005 case-control studies). The data collated were split into four separate and comparable substudies related to either the pre-FMD or post-FMD period, which are brought together and discussed here for the first time. The findings suggest that the risk factors associated with TB breakdowns may have changed. Higher Mycobacterium bovis prevalence in badgers following the FMD epidemic may have contributed to the identification of the presence of badgers on a farm as a prominent TB risk factor only post-FMD. The strong emergence of contact/trading TB risk factors post-FMD suggests that the purchasing and movement of cattle, which took place to restock FMD-affected areas after 2001, may have exacerbated the TB problem. Post-FMD analyses also highlighted the potential impact of environmental factors on TB risk. Although no unique and universal solution exists to reduce the transmission of TB to and among British cattle, there is an evidence to suggest that applying the broad principles of biosecurity on farms reduces the risk of infection. However, with trading remaining as an important route of local and long-distance TB transmission, improvements in the detection of infected animals during pre- and post-movement testing should further reduce the geographical spread of the disease.

Everything is Bigger in Texas, Including the Latino Adolescent Pregnancy Rate: How Do We Eliminate the Epidemic of Latino Teen Pregnancy?

A commentary on Tortolero et al.'s article entitled, "Latino Teen Pregnancy in Texas: Prevalence, Prevention, and Policy."

Influenza vaccination and cardiovascular risk in patients with recent TIA and stroke

OBJECTIVES: To determine whether current influenza vaccination is associated with reduced risk of major vascular events in patients with recent ischemic stroke or TIA of mainly atherothrombotic origin. METHODS: Data were pooled from 2 prospective cohort studies, the OPTIC Registry (n = 3,635) and the AMISTAD Study (n = 618), and from the randomized PERFORM Trial (n = 19,120), all of which included patients with recent ischemic stroke or TIA. Influenza vaccination status was determined in 23,110 patients. The primary outcome was a composite of nonfatal myocardial infarction, nonfatal stroke, or vascular death up to 2 years. Secondary outcomes were myocardial infarction and stroke separately. RESULTS: Influenza vaccination had no association with the primary outcome in the propensity score-matched cohort (hazard ratio 0.97, 95% confidence interval [CI] 0.85-1.11; p = 0.67) or in the propensity score-adjusted cohort (hazard ratio 1.00, 95% CI 0.89-1.12; p = 0.99). Similarly, the risk of stroke and myocardial infarction did not differ between the vaccinated group and the unvaccinated group; in the matched cohort, the hazard ratio was 1.01 (95% CI 0.88-1.17; p = 0.89) for stroke and 0.84 (95% CI 0.59-1.18; p = 0.30) for myocardial infarction. CONCLUSIONS: Influenza vaccination was not associated with reduced outcome events in patients with recent atherothrombotic ischemic stroke after considering all baseline characteristics (including concomitant medications) associated with influenza vaccination.

Hepatitis C: a changing epidemic.

Approximately 3% of the world population is estimated to have a chronic hepatitis C virus (HCV) infection and 500,000 individuals die from its consequences yearly. Persons who inject drugs (PWID) bear the majority of the disease burden in high-income countries. Drug substitution programmes have helped reduce HCV transmissions among PWID. However, recent epidemics of sexually transmitted HCV infections in HIV-infected men who have sex with men demonstrated the changing nature of the HCV epidemic. HCV therapy is undergoing a revolution, as new interferon-free, oral treatments eradicate HCV infections in almost all treated patients. As a consequence, the eradication of HCV has become a matter of debate and is becoming an important future public health target. However, for this to be achieved, many challenges need to be addressed, including the poor uptake of HCV testing, the high cost of the new antiviral combinations and the high frequency of re-infections after treatment in some populations.

Severity assessment tools in ICU patients with 2009 influenza A (H1N1) pneumonia.

The aim of this study was to determine if severity assessment tools (general severity of illness and community-acquired pneumonia specific scores) can be used to guide decisions for patients admitted to the intensive care unit (ICU) due to pandemic influenza A pneumonia. A prospective, observational, multicentre study included 265 patients with a mean age of 42 (±16.1) years and an ICU mortality of 31.7%. On admission to the ICU, the mean pneumonia severity index (PSI) score was 103.2 ± 43.2 points, the CURB-65 score was 1.7 ± 1.1 points and the PIRO-CAP score was 3.2 ± 1.5 points. None of the scores had a good predictive ability: area under the ROC for PSI, 0.72 (95% CI, 0.65-0.78); CURB-65, 0.67 (95% CI, 0.59-0.74); and PIRO-CAP, 0.64 (95% CI, 0.56-0.71). The PSI score (OR, 1.022 (1.009-1.034), p 0.001) was independently associated with ICU mortality; however, none of the three scores, when used at ICU admission, were able to reliably detect a low-risk group of patients. Low risk for mortality was identified in 27.5% of patients using PIRO-CAP, but above 40% when using PSI (I-III) or CURB65 (<2). Observed mortality was 13.7%, 13.5% and 19.4%, respectively. Pneumonia-specific scores undervalued severity and should not be used as instruments to guide decisions in the ICU.

Use of early corticosteroid therapy on ICU admission in patients affected by severe pandemic (H1N1)v influenza A infection.

INTRODUCTION Early use of corticosteroids in patients affected by pandemic (H1N1)v influenza A infection, although relatively common, remains controversial. METHODS Prospective, observational, multicenter study from 23 June 2009 through 11 February 2010, reported in the European Society of Intensive Care Medicine (ESICM) H1N1 registry. RESULTS Two hundred twenty patients admitted to an intensive care unit (ICU) with completed outcome data were analyzed. Invasive mechanical ventilation was used in 155 (70.5%). Sixty-seven (30.5%) of the patients died in ICU and 75 (34.1%) whilst in hospital. One hundred twenty-six (57.3%) patients received corticosteroid therapy on admission to ICU. Patients who received corticosteroids were significantly older and were more likely to have coexisting asthma, chronic obstructive pulmonary disease (COPD), and chronic steroid use. These patients receiving corticosteroids had increased likelihood of developing hospital-acquired pneumonia (HAP) [26.2% versus 13.8%, p < 0.05; odds ratio (OR) 2.2, confidence interval (CI) 1.1-4.5]. Patients who received corticosteroids had significantly higher ICU mortality than patients who did not (46.0% versus 18.1%, p < 0.01; OR 3.8, CI 2.1-7.2). Cox regression analysis adjusted for severity and potential confounding factors identified that early use of corticosteroids was not significantly associated with mortality [hazard ratio (HR) 1.3, 95% CI 0.7-2.4, p = 0.4] but was still associated with an increased rate of HAP (OR 2.2, 95% CI 1.0-4.8, p < 0.05). When only patients developing acute respiratory distress syndrome (ARDS) were analyzed, similar results were observed. CONCLUSIONS Early use of corticosteroids in patients affected by pandemic (H1N1)v influenza A infection did not result in better outcomes and was associated with increased risk of superinfections.