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Vaccination and Public Health
Biologicals (1997) 25, 121–123
Vaccination and Public Health Laurent Chambaud European Commission Directorate General V/F/1, Bax timent Jean Monnet, Plateau du Kirchberg, L-2920 Luxembourg, Luxembourg Introduction ‘‘Every friend of humanity must look with pleasure on this discovery, by which one evil more is withdrawn from the condition of man; and must contemplate the possibility that future improvements and discoveries may still more and more lessen the catalogue of evils.’’ This message was delivered in 1800 by Thomas Jefferson and it is not very difficult to find out which disease it was referred to: smallpox, of course. The eventual eradication of smallpox as a result of the use of vaccination was predicted by Edward Jenner, as well as by Thomas Jefferson, in the early 19th century. This was achieved some years ago, in fact in 1977 if we consider the last case, or in 1980 if we prefer the official certification by WHO. A long long way from the discovery of vaccines to the eradication of a disease. This presentation will try to answer three simple questions: do we need vaccines in public health? What are we presently doing? Can we do more? This long way from the discovery of a vaccine to the eradication of a disease illustrates the fact that public health has not only to deal with the discovery and production of vaccine—subjects which will be developed by my colleagues from the Commission— but it has to take into account many other factors: —Some factors refer to the disease itself: the incidence and severity of the disease, the possibility of treatment or prevention measures other than vaccination, the existence or not of an animal reservoir for the agent, the nature of the agent and routes of transmission, its geographical distribution and rapidity of spread of the disease; —Some other factors refer to technical specificity of the product: the efficacy of vaccination in theory and ‘‘in the field’’, including the concept of ‘‘herd immunity’’, the type and length of immunity conferred by the vaccine, the nature and frequency of adverse effects, and also an economic analysis, that is to say the costs and benefits of vaccination vs. costs induced by the disease itself; 1045–1056/97/020121 + 03 $25.00/0/bg970069
—Finally, a third category of factors could influence considerably the vaccination campaigns: the schedule of vaccination demanding several injections could be seen by the population as too cumbersome and intrusive, the price of vaccination could prevent some populations or even whole countries to afford mass distribution, or cultural aspects of the populations could stand in the way of achieving a good coverage of vaccination programmes. All these factors have to be taken into account when we want to integrate vaccination in a public health perspective. And I would like to underline a very important point for us: vaccination as such is not an objective in public health. We do not want the use and production of a vaccine without a clear and constant link with the main objective, that is to say to reduce the burden of a disease. Vaccination, in this perspective, is and has to remain a tool for prevention and control of a disease. A very useful, very powerful tool, but not the only one and it has to be integrated in a broader strategy of prevention and control. Do we need vaccines for this strategy? I am sure that, in this forum, you do not expect me to give a negative reply. We need vaccines, and the situation near the third millenium is far different from the beginning of this century. Let me remind you that, at that time, only smallpox and rabies immunization were available. We now have more than 20 diseases which can be prevented by immunization. But are they all really used in a public health perspective? We are not convinced that the answer to this question would be a definite and comprehensive ‘‘Yes’’. These doubts can be illustrated by two examples. —The Commission was invited, a few weeks ago, to a European conference on influenza in Lisbon. As you may know, we have a vaccine against influenza, and this vaccine is updated each year on the basis of a worldwide surveillance system. Are we prepared to react to a pandemic that will certainly occur in 7 1997 The International Association of Biological Standardization
122
L. Chambaud
the next few years? In that conference the results of a recent international survey were presented, showing that only five countries declared that they had prepared an operational plan to react to a worldwide epidemic. Of these five countries, only two belong to the European Union. —Second example, tuberculosis. This problem is more and more of concern in all Member States, especially with the emerging problem of resistance. But do we agree on the definition of the disease? On the usefulness of vaccination? Of control measures to be taken and contact tracing to be done? Obviously no. This is why the Commission is financing this year a feasibility study to evaluate the possibility of developing surveillance of tuberculosis at the European level.
diseases still spread all over the world, despite the existence of efficient vaccines. This is a reason why we are convinced that the control of preventable diseases, and particularly those preventable by immunization, cannot be achieved within the borders of one country. We have to work together at the European level. But we have also to be open to all the other countries, not only to protect our population, but also to help the others in solving their own problems. And, Europe has an expertise in this field that has to be shown and used.
This is why we are convinced that the development and use of vacination has to be clearly linked with its main objective: trying to reduce health problems caused by many communicable diseases. Even if research indicates that, in a few years, the scope of vaccination will increase to other diseases. But, in public health, we try to stick to what is possible to do and less on what is desirable to do. In the field of communicable diseases, many recent events are clear signals that we have to increase our awareness and try to forecast the near future. Here are some examples, among many others, of what happened very recently:
Until now, the main task in our directorate was to promote and develop a concrete basis for the establishment of surveillance networks. This is why the Commission prepared and published in March 1996 a proposal for creating a network for the epidemiological surveillance and control of communicable diseases in the European Community. The first group of diseases listed in the annex of this proposal is: diseases preventable by vaccination. This proposal is now being discussed by the Parliament and by the Council. We also are in a process of establishing an inventory of resources in the field of Communicable Diseases surveillance in the 15 Member States. We hope this inventory will be completed at the end of 1997. This inventory will collect information on diseases preventable by vaccination and on vaccination schedules in each Member State. In the programme of Community action on the prevention of Aids and certain other Communicable Diseases, one part is on Surveillance and monitoring of Communicable diseases. This programme could fund networks of diseases that can be prevented by vaccination and, thus, monitor the efficacy of vaccination programmes. Finally, a Task Force on communicable diseases has been etablished between the US and European Union. Within this Task Force is discussed the possibility to support a global early warning system on communicable diseases. No need to say that vaccination will be an important point of discussion. We do not know how communicable diseases will evolve in the future. What we already know is that we will have to react quickly. The epidemics of AIDS or the recent outbreaks of Ebola virus stand as powerful reminders of this.
—In the weekly Epidemiological Record from WHO-Geneva, 16th of August, it was stated that ‘‘overall, reported diphtheria cases in the Newly Independent States in 1995 increased by 5⋅8%, with more than 1500 deaths in 1995. Since the epidemic began, more than 120 000 cases and 4000 deaths have been reported in the NIS;’’ —there is now an outbreak of polio virus type 1 in Albania with a total of 77 cases on the 26th of September 1996, of which 10 have died. The outbreak began in June 1996 and occurred among the adolescent and adult population that was exposed to an incomplete polio vaccination schedule in the past. —In the last issue of the new European communicable disease bulletin ‘‘Eurosurveillance’’, a report was published on a mumps epidemic in Portugal in 1995/1996 despite high vaccine coverage. The possibility of a low efficacy of one strain is raised by the authors. We could add a lot of other examples within or outside Europe. Obviously, many communicable
What are we doing in the field of public health?
Vaccination and public health
But can we do more? Of course yes. Some suggestions can be advanced: First, we could make progress in better co-operation between Member States with respect to vaccination schedules and recommendations. We are far away from a single vaccination schedule and policy within the European Union. And this could affect the lives of European citizens because not only do they have to face different regulations (compulsory in some Member States, recommended in others), but also they have to cope with different vaccine guidelines as they are based on scientific opinions that could vary from one Member State to the other (different recommendations, different schedules . . .). On the other hand, total harmonization is impracticable, if not contra-indicated. But some steps could be taken towards the important continuity of protection: first we have to collect precise information on the different vaccination schedules and policies in each disease. Second, we need a scientific opinion at the European level on the indications and schedules to be recommended. Perhaps a scientific committee on vaccination could be set up for this purpose at the European level. This scientific opinion could also be given through another forum, that is to say travel medicine. It could be of value to have clear indications by a scientific society for travel medicine on what we have to recommend to a European citizen who has, for instance, to travel to Albania or has to work for prolonged periods in
123
another country. Finally, we need to develop colaborative networks on communicable diseases preventable by vaccination. This could be done through the AIDS and other communicable diseases programme. But, referring to the theme of this meeting, we also need to develop surveillance and monitoring of adverse effects and efficacy of these vaccines. We are convinced that this could be achieved by close collaboration between physicians, public health professionals, and the vaccines producers who need this information. In conclusion, let me leave you with this comment on the importance of prevention, from a very well-known ‘‘counsellor’’ in political matters: The Importance of Prevention Wise rulers ‘‘have to deal not only with existing troubles, but with troubles that are likely to develop, and have to use every means to overcome them. For if the first signs of trouble are perceived, it is easy to find a solution; but if one lets trouble develop, the medicine will be too late, because the malady will have become incurable, and what physicians say about consumptive diseases is also true of this matter, namely that at the beginning of the illness it is easy to treat but difficult to diagnose but, if it has not been diagnosed and treated at an early stage, as time passes it becomes easy to diagnose but difficult to treat.’’ Machiavelli (The Prince).
Vaccination and Public Health Laurent Chambaud European Commission Directorate General V/F/1, Bax timent Jean Monnet, Plateau du Kirchberg, L-2920 Luxembourg, Luxembourg Introduction ‘‘Every friend of humanity must look with pleasure on this discovery, by which one evil more is withdrawn from the condition of man; and must contemplate the possibility that future improvements and discoveries may still more and more lessen the catalogue of evils.’’ This message was delivered in 1800 by Thomas Jefferson and it is not very difficult to find out which disease it was referred to: smallpox, of course. The eventual eradication of smallpox as a result of the use of vaccination was predicted by Edward Jenner, as well as by Thomas Jefferson, in the early 19th century. This was achieved some years ago, in fact in 1977 if we consider the last case, or in 1980 if we prefer the official certification by WHO. A long long way from the discovery of vaccines to the eradication of a disease. This presentation will try to answer three simple questions: do we need vaccines in public health? What are we presently doing? Can we do more? This long way from the discovery of a vaccine to the eradication of a disease illustrates the fact that public health has not only to deal with the discovery and production of vaccine—subjects which will be developed by my colleagues from the Commission— but it has to take into account many other factors: —Some factors refer to the disease itself: the incidence and severity of the disease, the possibility of treatment or prevention measures other than vaccination, the existence or not of an animal reservoir for the agent, the nature of the agent and routes of transmission, its geographical distribution and rapidity of spread of the disease; —Some other factors refer to technical specificity of the product: the efficacy of vaccination in theory and ‘‘in the field’’, including the concept of ‘‘herd immunity’’, the type and length of immunity conferred by the vaccine, the nature and frequency of adverse effects, and also an economic analysis, that is to say the costs and benefits of vaccination vs. costs induced by the disease itself; 1045–1056/97/020121 + 03 $25.00/0/bg970069
—Finally, a third category of factors could influence considerably the vaccination campaigns: the schedule of vaccination demanding several injections could be seen by the population as too cumbersome and intrusive, the price of vaccination could prevent some populations or even whole countries to afford mass distribution, or cultural aspects of the populations could stand in the way of achieving a good coverage of vaccination programmes. All these factors have to be taken into account when we want to integrate vaccination in a public health perspective. And I would like to underline a very important point for us: vaccination as such is not an objective in public health. We do not want the use and production of a vaccine without a clear and constant link with the main objective, that is to say to reduce the burden of a disease. Vaccination, in this perspective, is and has to remain a tool for prevention and control of a disease. A very useful, very powerful tool, but not the only one and it has to be integrated in a broader strategy of prevention and control. Do we need vaccines for this strategy? I am sure that, in this forum, you do not expect me to give a negative reply. We need vaccines, and the situation near the third millenium is far different from the beginning of this century. Let me remind you that, at that time, only smallpox and rabies immunization were available. We now have more than 20 diseases which can be prevented by immunization. But are they all really used in a public health perspective? We are not convinced that the answer to this question would be a definite and comprehensive ‘‘Yes’’. These doubts can be illustrated by two examples. —The Commission was invited, a few weeks ago, to a European conference on influenza in Lisbon. As you may know, we have a vaccine against influenza, and this vaccine is updated each year on the basis of a worldwide surveillance system. Are we prepared to react to a pandemic that will certainly occur in 7 1997 The International Association of Biological Standardization
122
L. Chambaud
the next few years? In that conference the results of a recent international survey were presented, showing that only five countries declared that they had prepared an operational plan to react to a worldwide epidemic. Of these five countries, only two belong to the European Union. —Second example, tuberculosis. This problem is more and more of concern in all Member States, especially with the emerging problem of resistance. But do we agree on the definition of the disease? On the usefulness of vaccination? Of control measures to be taken and contact tracing to be done? Obviously no. This is why the Commission is financing this year a feasibility study to evaluate the possibility of developing surveillance of tuberculosis at the European level.
diseases still spread all over the world, despite the existence of efficient vaccines. This is a reason why we are convinced that the control of preventable diseases, and particularly those preventable by immunization, cannot be achieved within the borders of one country. We have to work together at the European level. But we have also to be open to all the other countries, not only to protect our population, but also to help the others in solving their own problems. And, Europe has an expertise in this field that has to be shown and used.
This is why we are convinced that the development and use of vacination has to be clearly linked with its main objective: trying to reduce health problems caused by many communicable diseases. Even if research indicates that, in a few years, the scope of vaccination will increase to other diseases. But, in public health, we try to stick to what is possible to do and less on what is desirable to do. In the field of communicable diseases, many recent events are clear signals that we have to increase our awareness and try to forecast the near future. Here are some examples, among many others, of what happened very recently:
Until now, the main task in our directorate was to promote and develop a concrete basis for the establishment of surveillance networks. This is why the Commission prepared and published in March 1996 a proposal for creating a network for the epidemiological surveillance and control of communicable diseases in the European Community. The first group of diseases listed in the annex of this proposal is: diseases preventable by vaccination. This proposal is now being discussed by the Parliament and by the Council. We also are in a process of establishing an inventory of resources in the field of Communicable Diseases surveillance in the 15 Member States. We hope this inventory will be completed at the end of 1997. This inventory will collect information on diseases preventable by vaccination and on vaccination schedules in each Member State. In the programme of Community action on the prevention of Aids and certain other Communicable Diseases, one part is on Surveillance and monitoring of Communicable diseases. This programme could fund networks of diseases that can be prevented by vaccination and, thus, monitor the efficacy of vaccination programmes. Finally, a Task Force on communicable diseases has been etablished between the US and European Union. Within this Task Force is discussed the possibility to support a global early warning system on communicable diseases. No need to say that vaccination will be an important point of discussion. We do not know how communicable diseases will evolve in the future. What we already know is that we will have to react quickly. The epidemics of AIDS or the recent outbreaks of Ebola virus stand as powerful reminders of this.
—In the weekly Epidemiological Record from WHO-Geneva, 16th of August, it was stated that ‘‘overall, reported diphtheria cases in the Newly Independent States in 1995 increased by 5⋅8%, with more than 1500 deaths in 1995. Since the epidemic began, more than 120 000 cases and 4000 deaths have been reported in the NIS;’’ —there is now an outbreak of polio virus type 1 in Albania with a total of 77 cases on the 26th of September 1996, of which 10 have died. The outbreak began in June 1996 and occurred among the adolescent and adult population that was exposed to an incomplete polio vaccination schedule in the past. —In the last issue of the new European communicable disease bulletin ‘‘Eurosurveillance’’, a report was published on a mumps epidemic in Portugal in 1995/1996 despite high vaccine coverage. The possibility of a low efficacy of one strain is raised by the authors. We could add a lot of other examples within or outside Europe. Obviously, many communicable
What are we doing in the field of public health?
Vaccination and public health
But can we do more? Of course yes. Some suggestions can be advanced: First, we could make progress in better co-operation between Member States with respect to vaccination schedules and recommendations. We are far away from a single vaccination schedule and policy within the European Union. And this could affect the lives of European citizens because not only do they have to face different regulations (compulsory in some Member States, recommended in others), but also they have to cope with different vaccine guidelines as they are based on scientific opinions that could vary from one Member State to the other (different recommendations, different schedules . . .). On the other hand, total harmonization is impracticable, if not contra-indicated. But some steps could be taken towards the important continuity of protection: first we have to collect precise information on the different vaccination schedules and policies in each disease. Second, we need a scientific opinion at the European level on the indications and schedules to be recommended. Perhaps a scientific committee on vaccination could be set up for this purpose at the European level. This scientific opinion could also be given through another forum, that is to say travel medicine. It could be of value to have clear indications by a scientific society for travel medicine on what we have to recommend to a European citizen who has, for instance, to travel to Albania or has to work for prolonged periods in
123
another country. Finally, we need to develop colaborative networks on communicable diseases preventable by vaccination. This could be done through the AIDS and other communicable diseases programme. But, referring to the theme of this meeting, we also need to develop surveillance and monitoring of adverse effects and efficacy of these vaccines. We are convinced that this could be achieved by close collaboration between physicians, public health professionals, and the vaccines producers who need this information. In conclusion, let me leave you with this comment on the importance of prevention, from a very well-known ‘‘counsellor’’ in political matters: The Importance of Prevention Wise rulers ‘‘have to deal not only with existing troubles, but with troubles that are likely to develop, and have to use every means to overcome them. For if the first signs of trouble are perceived, it is easy to find a solution; but if one lets trouble develop, the medicine will be too late, because the malady will have become incurable, and what physicians say about consumptive diseases is also true of this matter, namely that at the beginning of the illness it is easy to treat but difficult to diagnose but, if it has not been diagnosed and treated at an early stage, as time passes it becomes easy to diagnose but difficult to treat.’’ Machiavelli (The Prince).