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Electron microscopy of the Variola major virus. Source: Hans Gelderblom/RKI

Smallpox Preparedness Plan: Anti-epidemic Measures After Smallpox Outbreak

In 2002 the Robert Koch Institute (RKI) was given the task by the Federal Ministry of Health to co-ordinate the compilation of a preparedness plan at the request of the German States. This should describe the preparations and countermeasures necessary for the control of an epidemic resulting from a bioterroristic attack with smallpox. In addition to the preparedness plan it also includes an annex with definitions, fact sheets and other information.

More than 20 years after the worldwide eradication of smallpox and cessation of vaccination a deliberate release of this agent would be extremely dangerous as the virus would be entering a population with virtually no protective immunity. There is currently no solid data concerning the levels of protection against smallpox in people vaccinated decades ago. It is therefore particularly important to detect an initial smallpox case at an early stage and to identify and vaccinate all potential contacts. The earlier that adequate countermeasures can be taken, the higher are the chances that an epidemic spread of the infection can be prevented.

The preparedness plan

The preparedness plan is divided into four main sections that broadly discuss the following focal points: diagnosis, anti-epidemic measures, organisation of vaccinations and treatment.The plan highlights the measures necessary for managing the anti-epidemic campaign. Following a description of the implementation, the requirements for the preparedness planning in terms of organisation, personnel and material are laid out. These requirements were selected according to strict scientific criteria. Although the measures are listed in a chronological or hierarchical order, in the case of a real emergency most will have to be implemented with equal priority and possibly simultaneously.

Early detection, risk assessment and intervention are the three major areas of the preparedness plan in which the single steps for preparing and implementing the necessary measures are described in detail.

Area 1: early detection

This area covers the early detection of a smallpox case from clinical diagnosis to laboratory confirmation. The detection of a smallpox case calls for familiarity with the disease pattern. The number of active physicians nowadays who have clinical experience with smallpox patients is very low and it is therefore necessary that they become familiar with the disease pattern, including differential diagnosis. This is the only sure way that the probability of early detection of smallpox cases can enhanced.

The professional implementation of sampling techniques and storage as well as transport have to be regulated in advance to avoid any unnecessary loss of time or danger from improper handling or packaging. On the other hand, the laboratories selected for the smallpox diagnostics have to guarantee that this can be done both rapidly and with assured quality. These laboratories have to immediately report a suspected or confirmed laboratory diagnosis to the appropriate authorities.

Area 2: risk assessement

An initial suspected case already triggers various notifications that are required by the German Protection against Infection Act (IfSG) and international health regulations. Furthermore, if it appears to have been a deliberate release of the virus, an actual threat to the Federal Republic of Germany has to be presumed. In this case, in addition to the responsible health authorities, crisis management organisations will have to act in order to guarantee a comprehensive management in case of a confirmation and a spread of the epidemic.

In addition to the notifications based on the given case definitions certain measures are necessary to allow the initial risk of the epidemic spreading to be assessed. These measures follow the protocols of an outbreak investigation i.e. the activities focus on the tracing and identification of suspected exposed contacts and the sources of infection as well as an active search for cases. This allows a first impression of the epidemic situation to be formed. Decisions on further action are based on the corresponding circumstances.

Area 3: intervention

Anti-epidemic measures are also of considerable importance in the field of interventions. Permanent monitoring of the epidemic is necessary to guarantee that the effectiveness of the measures can be accurately evaluated, which in turn can lead to the introduction of new measures or to the modification of those measures already implemented. The following measures have to be distinguished:

Measures concerning smallpox patients:

Smallpox patients must be transferred immediately for further treatment to a hospital with an isolation unit.

Measures concerning contacts of infected persons:

Most important is the incubation-vaccination of the contact person (subject to § 20 of the Protection against Infection Act) followed by their observation and, if necessary, isolation (subject to §§ 28-32 of the Protection against Infection Act). The indications and treatments of complications resulting from vaccination are also presented.

Measures concerning the population:

In the event of a smallpox outbreak the population can be protected by the prompt implementation of a vaccination campaign. A graded procedure is proposed which can be adjusted to the developing epidemic including, as a measure of last resort, the mass vaccination of the entire population or major parts of it.

Furthermore the spread of a smallpox epidemic can be counteracted by limiting access to public facilities and events and by restricting freedom of movement. In addition, recommending appropriate protective measures and risk avoidance behaviour will be helpful.

Closely related to this is communication with the public. This is probably the most important contribution to an appropriate risk management, as a positive effect on the reactions of the population requires a transparent and comprehensive information policy.

Another important aspect is international co-operation, including exchange and coordination of information as well as the request for and the provision of technical and personnel support.

The phase model

The considerations and recommendations of the RKI are based on a model that has three phases.

Phase 1: No case of smallpox worldwide
Phase 2: First case of smallpox worldwide
Phase 3: First case of smallpox in Germany OR first case of smallpox abroad posing a direct threat to the German population

Such models serve as a helpful frame for planning and suggest a chronological order that does not necessarily have to be reflected by reality, e.g. a direct transition from phase 1 to phase 3 is possible.

Where required the recommendations in the preparedness plan have been adapted to these phases although a large part of the preparations has to be already implemented in phase 1. These preparations are necessary to enable immediate action to be taken in phases 2 and 3. They include the compilation of local smallpox preparedness plans as well as, for example, the training of staff, the establishment of the infrastructure and the provision of materials.

Annex: additional information

In addition to the remarks in the preparedness plan there is a compilation of documents in the annex which can be useful for the handling of infected or suspected cases as well as for the preparation and implementation of the vaccinations. The annex includes training material for the vaccination, hygiene measures and documentation of the vaccination. The leaflets included with the stored vaccines in Germany give further information on the vaccines, including not only their effects but also their risks. Contraindications for a smallpox vaccination have to be strictly adhered to in phases 1 and 2 but in phase 3 they have to be considered with regard to the risk of exposure. Some of the adverse effects possible as a result of vaccination can be treated. Important aspects such as transport and traffic connections, sanitary equipment and facilities have to be considered when planning the infrastructure of a vaccination site to enable a large number of people to be vaccinated in a very short time. The training of the necessary staff and the provision of the material needed at the site have to be organised in time. The regulations for the disposal of smallpox vaccine contaminated material are also included in the annex.

Summary

As soon as a suspected smallpox case is notified in Germany, the responsible health authority (and also the appropriate competence centre) must be consulted for a clinical clarification of the diagnosis. If the clinical diagnosis is confirmed the relevant authorities must be ready for action. A sample must be taken and sent to a laboratory that has been notified in advance.

If the disease is laboratory confirmed, immediate intervention will be initiated on the basis of the case definitions. All contacts of the index case and all other persons who could have become infected must be traced immediately – by questioning the infected or exposed cases and by identifying the source of infection. The group of suspected infectious cases must be vaccinated and isolated as soon and as completely as possible. The daily risk assessment on the spread of the epidemic forms the basis for the decision whether further actions, e.g. a general vaccination campaign, are to be taken. At the same time the general public has to be informed via the available media adapted to target groups and the situation. Information of general relevance can be broadcasted nationwide by television, for example, whereas information of regional or local relevance can make use of other media (radio, local newspapers, cars with loudspeakers, leaflets, etc.).

The information includes recommendations for protective measures as well as the announcement of restrictions on entry to events and facilities. The protection of the non-infected population can necessitate quarantine measures for suspect cases or measures restricting freedom of movement. As viruses do not recognise national boundaries, international co-operation is also of decisive importance. This may include technical and personnel support as well as the exchange and coordination of information.

Date: 01.10.2011