Immunization of high-risk paediatric populations: Central European Vaccination Awareness Group recommendations.

Over the last decade, childhood immunization has substantially reduced morbidity and mortality from vaccine-preventable diseases. However, particular paediatric risk groups, such as those with comorbidities, may not be adequately vaccinated despite being more susceptible to complications and death from certain infectious diseases. This may be due to lack of immunization recommendations, lack of awareness, or incomplete adherence to existing guidelines. Furthermore, recommendations for immunization can be inconsistent across Europe. An expanded initiative from the Central European Vaccination Awareness Group aims to raise awareness of the different high-risk paediatric groups, differentiate them according to their specific risk, and formalise a guidance statement for the immunization of each population.

Rotavirus vaccination in central Europe.

Each year, rotavirus (RV) infection is the leading cause of acute gastroenteritis requiring hospitalisation and of nosocomially transmitted diseases in children younger than 5 years across Central European Vaccination Awareness Group (CEVAG) countries; however, inadequate surveillance systems and lack of routine RV testing still exist in most CEVAG countries, making it difficult to accurately assess the present burden of acute RV gastroenteritis in the younger population. Furthermore, routine immunisation of infants with RV vaccines has not been implemented, and no official and uniform recommendations exist in most of the countries in these territories. The present study provides CEVAG country-specific estimates of the disease burden of RV gastroenteritis among the youngest population and presents evidence-based advice on the use of RV vaccines in the region, while providing a framework for vaccination at the national level.

Recommendations for tick-borne encephalitis vaccination from the Central European Vaccination Awareness Group (CEVAG).

Tick-borne encephalitis (TBE) is a viral neurological zoonotic disease transmitted to humans by ticks or by consumption of unpasteurized dairy products from infected cows, goats, or sheep. TBE is highly endemic in areas of Central and Eastern Europe and Russia where it is a major public health concern. However, it is difficult to diagnose TBE as clinical manifestations tend to be relatively nonspecific and a standardized case definition does not exist across the region. TBE is becoming more important in Europe due to the appearance of new endemic areas. Few Central European Vaccination Awareness Group (CEVAG) member countries have implemented universal vaccination programmes against TBE and vaccination coverage is not considered sufficient to control the disease. When implemented, immunization strategies only apply to risk groups under certain conditions, with no harmonized recommendations available to date across the region. Effective vaccination programmes are essential in preventing the burden of TBE. This review examines the current situation of TBE in CEVAG countries and contains recommendations for the vaccination of children and high-risk groups. For countries at very high risk of TBE infections, CEVAG strongly recommends the introduction of universal TBE vaccination in children > 1 y of age onwards. For countries with a very low risk of TBE, recommendations should only apply to those traveling to endemic areas. Overall, it is generally accepted that each country should be free to make its own decision based on regional epidemiological data and the vaccination calendar, although recommendations should be made, especially for those living in endemic areas.

Group A rotavirus genotypes circulating prior to implementation of a National Immunization Program in Estonia.

Group A rotaviruses (RVA) are a major cause of acute gastroenteritis in children ≤ 5 y worldwide which could be prevented with two recently introduced vaccines - monovalent Rotarix (live-attenuated G1P[8] strain) and pentavalent RotaTeq (human-bovine reassortant containing serotypes G1, G2, G3, G4 and P[8]). Prior to implementation of vaccines into national immunization program we aimed to describe RVA genotype distribution in hospitalized children aged < 5 y in Estonia during 2007-2008. A total of 671 children with confirmed RVA gastroenteritis from three major pediatric hospitals were prospectively enrolled. G- and P-genotypes were detected from 124 stool samples by semi-nested reverse transcription-PCR. Severity of disease was assessed using Clark scoring system. The majority of cases (65%) occurred in infants aged 7 to 24 mo and were of moderate severity (mean Clark score 12.1 (SD 3.2)). The prevailing strain was G2P[4] (34.7%), causing significantly more cases than G4P[8] (12.9%), G1P[8] or G9P[8] (both 4.0%), G3P[8] (1.6%). Yearly differences in genotype distribution occurred, as G2P[4] (52.8%) dominated in 2007, but G4P[8] (26.9%) in 2008. One third of strains remained non-typeable. The distribution of RVA genotypes in Estonia differs from that seen in other Central and Eastern European countries, although one should bear in mind the large proportion of P-untypeable strains and natural fluctuations of dominating RVA genotypes. Nevertheless, considering the high genotype-independent efficacy of the vaccines, introduction of national immunization should be considered.

Adult vaccination in 11 Central European countries - calendars are not just for children.

As Europe's population ages, disease morbidity and treatment costs in the adult population are likely to rise substantially, making this a pertinent time to review and revise preventive strategies such as vaccination. Vaccine uptake remains a problem for adults and there is a lack of coordinated programmes for vaccination of adults. Countries in Western Europe have begun to identify the need to increase adult vaccination, but the situation in Central European countries remains poorly identified and inadequately described. This paper summarises the evidence to support the development of an adult vaccination calendar in the Central European Vaccination Awareness Group (CEVAG) member countries (Bulgaria, Croatia, the Czech Republic, Estonia, Hungary, Latvia, Lithuania, Romania, Slovakia, Slovenia and Turkey). CEVAG recommends the introduction of an adult vaccination calendar, which should include vaccination against diseases that represent a large burden in adults in terms of mortality and morbidity. This calendar could be modified to meet the priorities of individual countries.

Rubella revisited: where are we on the road to disease elimination in Central Europe?

Rubella is a contagious viral disease with few complications except when contracted by pregnant women. Rubella infection in pregnancy can result in miscarriage, stillbirth or an infant born with congenital rubella syndrome (CRS) which comprises deafness, heart disease, cataracts and other permanent congenital manifestations. Clinical diagnosis of rubella is difficult due to overlapping symptoms with many other diseases and confirmation of rubella is not possible without laboratory testing. Effective vaccination programmes are critical to the elimination of rubella and prevention of CRS. Such programmes have been successful in several countries in Europe and around the world. However, rubella outbreaks still occur due to suboptimal vaccine coverage and in the past 10 years rubella has been reported in Central European countries such as Romania and Poland. Over the past decade the elimination of rubella and prevention of congenital rubella infection in Europe has been a high priority for the WHO European Regional Office. In 2010 the WHO regional committee for Europe renewed its commitment to the elimination of rubella and prevention of CRS with a new target of 2015. This paper examines the current situation for rubella and CRS in Central Europe and describes the different rubella vaccination programmes in the region. The Central European Vaccination Advisory Group (CEVAG) recommends that two doses of measles, mumps and rubella vaccine, MMR, should be given to all children. The first dose should be given between 12 and 15 months of age. The second dose can be given between the ages of 21 months and 13 years with the exact age of administration of the second dose depending on the situation specific to each country. All suspected rubella cases should be laboratory-confirmed and monitoring systems to detect and investigate cases of CRS should be strengthened.

Central European Vaccination Advisory Group (CEVAG) guidance statement on recommendations for influenza vaccination in children.

BACKGROUND: Influenza vaccination in infants and children with existing health complications is current practice in many countries, but healthy children are also susceptible to influenza, sometimes with complications. The under-recognised burden of disease in young children is greater than in elderly populations and the number of paediatric influenza cases reported does not reflect the actual frequency of influenza. DISCUSSION: Vaccination of healthy children is not widespread in Europe despite clear demonstration of the benefits of vaccination in reducing the large health and economic burden of influenza. Universal vaccination of infants and children also provides indirect protection in other high-risk groups in the community. This paper contains the Central European Vaccination Advisory Group (CEVAG) guidance statement on recommendations for the vaccination of infants and children against influenza. The aim of CEVAG is to encourage the efficient and safe use of vaccines to prevent and control infectious diseases. SUMMARY: CEVAG recommends the introduction of universal influenza vaccination for all children from the age of 6 months. Special attention is needed for children up to 60 months of age as they are at greatest risk. Individual countries should decide on how best to implement this recommendation based on their circumstances.

Central European Vaccination Advisory Group (CEVAG) guidance statement on recommendations for 2009 pandemic influenza A(H1N1) vaccination.

The 2009 influenza A(H1N1) pandemic is markedly different from seasonal influenza with the disease affecting the younger population and a larger than expected number of severe or fatal cases has been seen in pregnant women, obese people and in people who were otherwise healthy. In Europe, influenza activity caused by the 2009 influenza A(H1N1) virus has passed the winter peak with nearly all countries now reporting lower influenza activity. However, although the rate of 2009 pandemic influenza A(H1N1) is declining, fatal cases continue to be reported and the future is hard to predict. The most effective protection against influenza is vaccination and increasing vaccine coverage is the only way to eliminate uncertainties regarding possible future waves of 2009 pandemic influenza A(H1N1). Recommendations have been developed for several central European countries but there is no clear or uniform definition with respect to priority groups or age groups who should receive vaccination. This paper contains the Central European Vaccination Advisory Group (CEVAG) guidance statement on recommendations for the vaccination of adults and children against 2009 pandemic influenza A(H1N1). CEVAG recommends vaccination of all health-care workers, pregnant women, children > or = 6 months and <2 years of age and people with chronic medical conditions as a first priority.

Safety and immunogenicity of a primary course and booster dose of a combined diphtheria, tetanus, acellular pertussis, hepatitis B and inactivated poliovirus vaccine.

Primary immunization at 3, 4.5, and 6 months and boosting between 15 and 27 months of age with combined diphtheria-tetanus-acellular pertussis-hepatitis B-inactivated poliovirus (DTPa-HBV-IPV) vaccine was compared with separate administration of DTPa-HBV and IPV to healthy children (trials DTPa-HBV-IPV-019/033). Antibody titres were measured before and 1 month after primary and booster courses. Solicited local and general symptoms were recorded using diary cards. One month after primary vaccination, all children in both groups developed antibody titres above the assay cut-off for all vaccine components. Significantly higher anti-diphtheria, anti-pertactin (PRN) and anti-polio GMTs were measured following DTPa-HBV-IPV than DTPa-HBV plus IPV. Prior to boosting similar seroprotection/seropositivity rates were recorded in both groups. After boosting all children had seroprotective levels of diphtheria, tetanus, polio and HBV. Criteria for pertussis vaccine response were fulfilled in most children. Significantly higher anti-PRN GMTs were measured following DTPa-HBV-IPV than DTPa-HBV plus IPV. There was no difference between groups in the incidence or intensity of local and general symptoms after primary or booster vaccination, except for fever which was more frequent after the booster dose in the combined vaccine group. Both vaccine regimens were well tolerated and immunogenic, however the combined administration has the advantage of being administered as a single injection.

Pertussis outbreak in a basic school in Estonia: description, contributing factors and vaccine effectiveness.

The aim of the current study was to assess the epidemiological situation concerning the emergence of a pertussis outbreak, as well as potential contributing factors and vaccine effectiveness. A retrospective epidemiological description and an analysis of the outbreak among students were performed. The basic school in Adavere had a total of 150 students in 2003. Of these, 54 cases of pertussis, with median age 12 y, all corresponding to clinical case definition, were identified with an attack rate of 36%. Regarding confirmation of the diagnosis, out of all clinical cases, 18 were confirmed by laboratory testing (2 by isolation of B. pertussis and 16 serologically based on single sera) and 36 with epidemiological linkage only. Of all the students with pertussis, 35 (65%) had received 4 doses and 6 (11%) 3 doses of DTwP vaccine; 13 (24%) students had received fewer than 3 doses or were unvaccinated. The contributing factors in generating this outbreak were close epidemiological contacts, late identification of pertussis diagnosis in the primary, secondary and later cases, as well as a too late initiated active surveillance. In this outbreak, low vaccine effectiveness and low vaccination coverage also played an important role.

Double-blind study comparing the immunogenicity of a licensed DTwPHib-CRM197 conjugate vaccine (Quattvaxem) with three investigational, liquid formulations using lower doses of Hib-CRM197 conjugate.

We performed a double-blind clinical study to evaluate the safety and immunogenicity of four formulations of a DTwPHib full liquid vaccine, three of which contained fractional doses of the 10 microg-dose of CRM197-Hib conjugate vaccine. A total of 261 infants were enrolled and randomised to receive at 3, 4 and 5 months of age, in a double-blind fashion, one of the four DTwPHib vaccine formulations containing 10, 5, 2.5 or 1.25 microg of CRM197-Hib conjugate. Post-immunization reactions were similar in the four vaccine groups, they were mild, transient and resolved without sequelae. The seroconversion rates to anti-PRP titres > or = 0.15 microg/mL were 100%, 98%, 97% and 98% in the groups 10, 5, 2.5 and 1.25 microg, respectively. The seroconversion rates to anti-PRP titres > or =1 microg/mL were 95%, 97%, 88% and 90%, again respectively. Anti-PRP GMTs were 18, 17, 7.82 and 6.94 microg/mL, respectively. All subjects were protected against tetanus and diphtheria, and >80% seroconverted to pertussis. High, and similar, levels of anti-PRP GMTs were elicited by the formulations with 10 and 5 microg of CRM197-Hib conjugate. Although the formulations with 2.5 and 1.25 microg of CRM197-Hib elicited lower levels of anti-PRP GMTs, they were immunogenic and are possible candidates for further development.

Antibiotic policies in Central Eastern Europe.

To assess the antibiotic policies in Central Eastern European (CEE) countries, a questionnaire on the prevalence of resistance, antibiotic consumption data for ambulatory and hospital care and antibiotic policies, was mailed to national representatives. Data on antibiotic resistance and consumption of antibiotics at national levels are limited and vary considerably among countries. The importance of surveillance data in altering perceptions of the prevalence of resistance is shown by the comparison of surveillance data and interview data. Interview data without surveillance data produced the widest range of estimates of the prevalence of resistance in streptococcus pneumonia -5% in Lithuania and 82% in Belarus. The average consumption of antibiotics in ambulatory care in eight CEE countries in 2001 was 19.35 defined daily doses (DDD)/1000 inhabitants per day, (range 13.1 - 24.8 DDD) and in hospitals in six CEE countries was 2.2 DDD/1000 inhabitants per day (range 1.3-4.5). Over the counter sales of antibiotics are available in some countries. Antibiotic policy interventions do not exist or only apply to specific problems or interventions. Better implementation of antibiotic interventions and education on antibiotic use should be a high priority in this region. An effective strategy requires close co-operation, consultations and partnership at national and international level in particular, via existing international organisations.