G. Peter

Varicella vaccine update

Recommendations for routine varicella vaccination were published by the American Academy of Pediatrics in May 1995, but many eligible children remain unimmunized. This update provides additional information on the varicella disease burden before the availability of varicella vaccine, potential barriers to immunization, efforts to increase the level of coverage, new safety data, and new recommendations for use of the varicella vaccine after exposure and in children with human immunodeficiency virus infections. Pediatricians are strongly encouraged to support public health officials in the development and implementation of varicella immunization requirements for child care and school entry.

Considerations on a Definition of Nanomaterial for Regulatory Purposes

The recent EU Cosmetic Products Regulation includes a labelling obligation for nanomaterials in the list of ingredients, in order to allow consumers to make a choice. Similar provisions are now being considered for other regulations/directives, e.g. the Novel Foods Regulation. Also the European chemicals legislation REACH may need adjustments to address and control the potential risk of nanomaterials. The introduction of these provisions specific to nanomaterials requires the adoption of a definition of the term ‘nanomaterial’. This need is also acknowledged by the European Parliament which has called for a comprehensive science-based definition in Community legislation. The report reviews and discusses issues related to a definition of the term ‘nanomaterial’. It gives a short overview about what may be considered as nanomaterials, their novel properties and applications. The need for a definition of nanomaterial is discussed, and the question of what should be achieved by a definition is addressed. The report gives an overview of definitions by international, national and European institutions, and lists approaches used in European legislation. It summarises the advantages and shortcomings of different elements typically used in available definitions, regarding their applicability in a regulatory context. The report concludes that a definition of the term ‘nanomaterial’ for regulatory purposes, only should concern ‘particulate nanomaterials’. The definition should ideally be broadly applicable in EU legislation and in line with other approaches worldwide. The following three key elements are identified as being crucial: (i) the term ‘material’, (ii) the nanoscale, and (iii) specific nanoscale properties. ‘Material’ and ‘nanoscale’ should both preferably be defined precisely in order to ease enforceability. This implies the introduction of precise nanoscale limits and instructions on how such limits can be applied to nanoscale materials with size distributions. For a basic and clear definition, which is broadly applicable and enforceable, it is recommended not to include properties other than size in a general definition. Shape and state of agglomeration/aggregation must be adequately dealt with either in the definition or in subsequent legislation. Other issues may need to be considered in specific regulations such as origin of the nanomaterial, properties other than size, and specific inclusion or exclusion of certain nanomaterials. The mission of the Joint Research Centre (JRC) is to provide customer-driven scientifi c and technical support for the conception, development, implementation and monitoring of European Union policies. As a service of the European Commission, the JRC functions as a reference centre of science and technology for the Union. Close to the policy-making process, it serves the common interest of the Member States, while being independent of special interests, whether private or national. LB -N A -2403-EN -C

Severe invasive group a streptococcal infections: A subject review

The course of severe invasive group A β-hemolytic streptococcal (GABHS) infections is often precipitous, requiring prompt diagnosis and rapid initiation of appropriate therapy. Therefore, physicians must have a high index of suspicion of this disease, particularly in patients at increased risk (eg, those with varicella or diabetes mellitus). Although a relationship between the use of nonsteroidal antiinflammatory drugs and severe invasive GABHS infections has been suggested, at present data on which to base a clinical decision about the use or restriction of nonsteroidal antiinflammatory drugs in children with varicella are insufficient. When necrotizing fasciitis is suspected, prompt surgical drainage, debridement, fasciotomy, or amputation often is necessary. Many experts recommend intravenously administered penicillin G and clindamycin for the treatment of invasive GABHS infections on the basis of animal studies. Some evidence exists that intravenous immunoglobulin given in addition to appropriate antimicrobial and surgical therapy may be beneficial. Although chemoprophylaxis for household contacts of persons with invasive GABHS infections has been considered by some experts, the limited available data indicate that the risk of secondary cases is low (2.9 per 1000) and data about the effectiveness of any drug are insufficient to make recommendations. Because of the low risk of secondary cases of invasive GABHS infections in schools or child care facilities, chemoprophylaxis is not indicated in these settings. Routine immunization of all healthy children against varicella is recommended and is an effective means to decrease the risk of invasive GABHS infections.

Requirements on measurements for the implementation of the European Commission definition of the term 'nanomaterial'

The European Commission recently published its recommendation on a common definition of the term “nanomaterial” for regulatory purposes. Proper implementation of this definition requires appropriate tools and methodologies for which measurement aspects are crucial. This report describes the requirements for particle size measurements of nanomaterials based on the definition. It discusses the related generic measurement issues and reviews the capabilities of the measurement methods currently available. Moreover, it illustrates with practical examples the measurement issues that remain to be solved. This report does not cover other related issues, such as the implementation of the definition by means other than through measurements, or methods to detect specific nanomaterials (such as fullerenes and single-wall carbon nanotubes), measurements to assess exposure to or effects of nanomaterials, or the detection and measurement of nanomaterials in consumer products. These will be addressed in a follow-up report.