Eurosurveillance - Volume 11, Issue 12, 01 December 2006

In May 2005 the World Health Assembly approved an innovative and ambitious revision of the International Health Regulations, known as IHR(2005), in order to detect and control, in a timely manner, all public health events that may have a serious international impact. It represents a dramatic move from administrative notification by Member States (MS) to the World Health Organization (WHO) of cases of a limited list of diseases to a systematic analysis of health events of international concern, infectious or not [1]. The analysis of the public health events will take into account severity, unexpectedness, potential for international spread, and interference with international movement of people and goods. National focal points are to be identified in each MS to interact with WHO. The philosophy behind the new IHR is to promote early dialogue between MS and WHO, leading to early mutual risk assessment of events which may not necessarily have to be notified, depending on the results of the assessment and measures taken. WHO can also use informal sources to detect earlier events of international concern and then, together with the national focal point, conduct verification, risk assessment and implement appropriate measures.

The adoption of the International Health Regulations (2005) (also referred to as IHR(2005) or the revised Regulations) provides a remarkable new legal tool for the protection of international public health. Upon entry into force on 15 June 2007, Article 2 (‘Purpose and scope‘) provides that the overall focus of the efforts of States Parties (and World Health Organization's efforts) under the revised Regulations will be to prevent, protect against, control and provide a public health response to the international spread of disease in ways that are commensurate with the public health risks and which avoid unnecessary interference with international traffic. Health measures under the revised Regulations will be implemented with respect for travellers’ human rights, with several specific new requirements in this area. To comply with the IHR (2005), States Parties (WHO member states that will be bound by the IHR(2005)) will have to have core public health capacities in disease surveillance and response, as well as additional capacities at designated international ports, airports and land crossings. This unique collective commitment will require close collaboration between WHO and the States Parties, but also intersectoral collaboration within the States themselves, including collaboration among different administrative or governmental levels, a particular issue for federal states, and horizontally across ministries and disciplines. Collaboration among States Parties is a key aspect of the revised Regulations, whether among neighbours, or with trading partners, members of regional economic integration organisations or other regional groups, or simply members of the international community. This collaboration is particularly relevant for the Member States of the European Union.

In a rapidly changing environment, national institutions in charge of health security can no longer rely only on traditional disease reporting mechanisms that are not designed to recognise emergence of new hazards. Epidemic intelligence provides a conceptual framework within which countries may adapt their public health surveillance system to meet new challenges. Epidemic intelligence (EI) encompasses all activities related to early identification of potential health hazards, their verification, assessment and investigation in order to recommend public health control measures. EI integrates both an indicator-based and an event-based component. ‘Indicator-based component’ refers to structured data collected through routine surveillance systems. ‘Event-based component’ refers to unstructured data gathered from sources of intelligence of any nature. All EU member states have long-established disease surveillance systems that provide proper indicator-based surveillance. For most countries, the challenge lies now in developing and structuring the event-based component of EI within national institution in charge of public health surveillance. In May 2006, the European Union member states committed to comply with provisions of the revised International Health Regulations (IHR(2005)) considered relevant to the risk posed by avian and potential human pandemic influenza. This provides for the European Centre for Disease Prevention and Control (ECDC) with an opportunity to guide member states in developing and/or strengthening their national EI , in addition to the ECDC’s task of developing an EI system for the EU.

Under Decision 2119/98/EC of the European Parliament and of the Council, a network for epidemiological surveillance and control of communicable diseases in the Community was set up in 1998. One pillar of Decision 2119/98/EC is the early warning and response system (EWRS). The main objective of the network is to establish permanent communication between European Union (EU) Member States’ public health authorities, which are responsible for determining the measures required to control communicable disease-related events. Since 1998, a web based informatics tool has been developed in order to allow information to be shared between the relevant public health authorities. Between 1998 and December 2005, a total of 583 messages were circulated through the EWRS, notifying 396 events. The information shared through the system helped to coordinate public health measures in the EU. However, only few events prompted specific measures at Community level and most of them were controlled with public health measures applied at national level. Major events (such as the Severe Acute Respiratory Syndrome) and the results of simulation exercises prompted the Commission to upgrade the informatics system on the basis of user needs. Since 1 May 2004 the 10 newest Member States have provided information under the current legislation and since April 2005 the European Centre for Disease Prevention and Control (ECDC) is part of the system. Future developments will include a link between the existing EWRS and the communication platform currently developed by the ECDC.

Routine primary care data provide the means to monitor a variety of syndromes which could give early warning of health protection issues. In the United Kingdom, a national syndromic surveillance system, operated jointly by the UK Health Protection Agency (HPA) and NHS Direct (a national telephone health helpline), examines symptoms reported to NHS Direct. The aim of the system is to identify an increase in syndromes indicative of common infections and diseases, or the early stages of illness caused by the deliberate release of a biological or chemical agent. Data relating to 11 key symptoms/syndromes are received electronically from all 22 NHS Direct call centres covering England and Wales and analysed by the HPA on a daily basis. Statistically significant excesses in calls are automatically highlighted and assessed by a multi-disciplinary team. Although the surveillance system has characterised many sudden rises in syndromes reported to NHS Direct, no evidence of a biological or chemical attack has been detected. Benefits of this work, however, are early warning and tracking of rises in community morbidity (e.g. influenza-like illness, heatstroke); providing reassurance during times of perceived high risk (e.g. after the 7 July 2005 London bombs and December 2005 Buncefield oil depot fire); and timely surveillance data for influenza pandemic planning and epidemic modeling.

Recent public health crises have shown the need for readily available information allowing proper management by decision-makers. One way of obtaining early information is to involve data providers who already record routine data for their own use. We describe here the results of a pilot network carried out by the InVS (Institut national de veille sanitaire) which gathered data available in real time from hospital emergency departments and register offices. Emergency departments data were registered from patients’ computerised medical files. Mortality data were received from the national institute of statistics (Insee). Data were transmitted automatically on a daily basis. Influenza data from outbreaks in 2004/05 and 2005/06 were compared with data from the sentinel network for the same periods. Environmental health data were compared with meteorological temperatures recorded in Paris between June and August 2006. A mortality analysis was conducted on a weekly basis. Correlation between influenza data from emergency departments and data from Sentiweb (sentinel network) was significant (p<0.001) for both outbreaks. In 2005 and 2006, the outbreaks were described similarly by both sources with identification of the start of the outbreaks by both systems during the same weeks. As for data related to heat, a significant correlation was observed between some diagnoses and temperature increases. For both types of phenomena, mortality increased significantly with one to two weeks lag. To our knowledge, this is the first time that a study using real time morbidity and mortality data is conducted. These initial results show how these data complement each other and how their simultaneous analysis in real time makes it possible to quickly measure the impact of a phenomenon.

Early detection of disease outbreaks is essential for authorities to initiate and conduct an appropriate response. A need for an outbreak detection that monitored data predating laboratory confirmations was identified, which prompted the establishment of a novel symptom surveillance system. The surveillance system monitors approximately 80% of the Danish population by applying an outbreak detection algorithm to ambulance dispatch data. The system also monitors both regional and national activity and has a built-in, switch-on capacity for implementing symptom surveillance reporting in case of an alert. In an evaluation with outbreak scenarios it was found that decreasing the outbreak detection sensitivity from a prediction limit of 95% to one of 99% moderately reduced the time to detection, but considerably diminished the number of false alerts. The system was able to detect an increased activity of influenza-like illness in December 2003 in a timely fashion. The system has now been implemented in the national disease surveillance programme.

The 2006 FIFA World Cup was held in 12 German cities between 9 June and 9 July 2006. We identified a need to accelerate and sensitise the pre-existing surveillance system for infectious diseases in order to timely detect adverse health events during the World Cup. Enhanced surveillance, based on Germany’s pre-existing system of mandatory notifications was conducted between 7 June and 11July 2006 in the 12 World Cup cities by: accelerating frequency of electronic data transmission of case-definition based notifiable diseases from weekly to daily transmission, additional reporting of non-case definition-based infectious disease events, lay and expert press screening and intensifying communication between all stakeholders of the surveillance system. Median delay of notification data transmission from the community to the federal level was reduced from three days to one day. The enhanced reporting system detected a norovirus outbreak in the International Broadcast Centre in Munich with 61 epidemiologically linked cases within the first week after onset, as well as four single cases related to the World Cup, two of them with relevance for the International Health Regulations. After the World Cup, all surveillance stakeholders agreed that communication between local, state and federal levels had improved considerably. Unlike the majority of health planners of previous mass gatherings in the last decade we did not introduce syndromic surveillance. Nevertheless, enhancement of infectious disease surveillance successfully detected adverse health events in a timely manner during the FIFA World Cup. Additionally, it provided a valuable communication and networking exercise for potentially critical health-related events. We recommend continuing daily notification data transmission for routine infectious disease surveillance in Germany.

Some of the competitions of the Olympic Winter Games in Torino, 10 to 26 February 2006, were organised in France near the city of Briançon, in the department of Hautes-Alpes. An epidemiologic surveillance system was set up by the local health authorities. The goals were to detect in a timely fashion any phenomenon which could justify prevention or sanitary control action, and to guide interventions in the case of outbreak or environmental pollution. Surveillance was implemented from 30 January to15 March 2006 in the Briançon area. Mortality was tracked using by analysing the number and cause of deaths. A sentinel network of general practitioners was set up and reported the frequency of acute gastroenteritis, influenza-like illness and measles. Medical laboratories provided data about the analyses they undertook. Hospital emergency department and emergency ambulance service activities were followed up. Statutory notification diseases and toxic effects of carbon monoxide surveillances were reinforced. Analysed data were transmitted daily to the health authorities. A French/English report was sent weekly to all participants. The participation rate was close to 100%, and data transmission deadlines were respected. No adverse health event was identified. The strong acceptability of this surveillance system comes from its good understanding by the participants. This surveillance, structured around routine and ad-hoc systems, allowed the establishment of the foundations of a network to be used in case of outbreak or environmental pollution.

The early warning committee was established in order to recognise threats to public health caused by infectious diseases in the Netherlands in a timely and complete fashion. This article describes the outcome of a retrospective and descriptive evaluation into the completeness of the recognitions made by the early warning committee. Information about outbreaks of infectious disease in the Netherlands in 2002 and 2003, as reported in the Nederlands Tijdschrift voor Geneeskunde (Dutch Journal of Medicine), and about infectious disease events in other countries, was compared with reports of the regular weekly meetings of the Dutch early warning committee. If an outbreak or a foreign event was not mentioned in the meetings of the early warning committee, the cause for this was established. For events in other countries, it was established on the basis of whether or not the event could have been a threat to public health in the Netherlands. All outbreaks of infectious disease in the Netherlands, published or mentioned in the Nederlands Tijdschrift voor Geneeskunde were discussed by the early warning committee. Three of the events occurring in other countries in 2002 had not been discussed by the committee although, based on the criteria for a potential threat to the Netherlands, they should have been: the outbreak of avian influenza A/H5N1 in domestic fowl in Hong Kong, the increase among hospitalised patients of carriers of extended-spectrum â-lactamase producing micro-organisms in Scotland, and outbreaks of measles in several countries. In 2003, all events in other countries that could have posed a threat to the Netherlands were discussed by the early warning committee. In 2002 and 2003, the early warning committee recognised nearly all threats due to infectious diseases and outbreaks of infectious diseases which were of national importance and published in various sources of literature.