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  Arguments Against Routine Mumps Immunization
  

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By: Hans-Ulrich Albonico, M.D.
(Original title: Argumente gegen die routinemaessige Mumpsimpfung. Sozial- und Praeventivmedizin. Basel: Birkhaeuser Verlag 1995. English by A. R. Meuss, FIL, MTA.)

Abstract
Routine immunization against mumps was included in the MMR elimination campaign in Switzerland in 1987 when, in fact, there was no need for this in public health terms. Seven years later practical experience had essentially refuted the theoretical basis for the mumps immunization campaign. Unnecessary vaccination is not very efficacious, with the incidence of complications increased. It also means that the general public loses confidence and begins to doubt the value of other immunizations. The apparent "failure" of mumps immunization also shows up inconsistencies in the whole MMR mass immunization campaign. Epidemiologically, the elimination project presents many hazards. Politically, the campaign, with its inherent elements of compulsion, encroaches on basic civil rights. The reasons why c. 20% of the population rejects mumps immunization have so far been little investigated by medical scientists. However, work done in three research areas points to the reasons for such an attitude: 1) maturation of the immune system is based on learning principles, which raises the question of the significance of childhood diseases in developing immunocompetence; 2) hyperthermia has become topical again in the treatment of cancer, which raises the question of the healing potential of pyrexia; 3) finally, concern is felt as to the long-term effect of manipulating the natural balance between humans and microorganisms.

Health, illness and personal responsibility
"Health for all by the year 2000" was the slogan the WHO used to introduce their medical and, above all, preventive programs for the last quarter of the century at the Alma Ata World Conference in 1978.(1) Initially, it referred to world-wide efforts to provide open access to adequate primary care. "Health" stood for "health care," with particular reference to third world countries where care was inadequate over large areas.

Implementation of the program did, however, lead to a fatal shift in meaning. "Health" increasingly became the "right to health." A reasonable demand for world-wide health care provision became a highly problematical issue - health as something people possess, with government guarantees. This inevitably led to demand for the eradication of diseases, and without considering the matter more deeply, disease became something essentially inimical to man and inhuman. Disease as the enemy of man - is that the only way in which it is seen today?

The concept of fighting diseases and, above all, infectious diseases with all available means had become a program.

Article 8 of the Alma Ata WHO Declaration calls for "maximum personal responsibility of society and the individual and participation in planning, organization, implementation and monitoring."(1) This was even more emphatically demanded at the 1988 World Conference in Riga: "People must be enabled to... take responsibility for their own health."(2) In the first place, this called for a definition of the most urgent health problems in a region that required health programs above the individual level, taking the form of government-supported campaigns. This evidently meant that in 1980, for instance, the people of Zimbabwe identified measles as a central problem, with a massive mortality of up to 10% in a country that had seen seven years of war and three years of drought, with 20% of 3-year-olds suffering from malnutrition.(3,4) An immunization campaign was initiated as part of the Expanded Programme on Immunization (EPI) (the author worked on the program in Zimbabwe from 1981-1983). It is doubtful, however, if the people of Switzerland would have defined measles, mumps and rubella, childhood diseases largely found to be normal and harmless, as one of the 10 major health problems when the national immunization campaign started in that country in 1987.

That is not the main point, however. It appears that a minority of about 20% is opposing the MMR immunization campaign, and this means failure of a campaign depending on at least 95% of the population being immunized, leaving aside the issue of immunization failures. Repeat immunization also will not prevent failure of the campaign.

Illness as a significant stage in the biography
What arguments can be brought against immunization for childhood diseases and specifically mumps? It is everyday experience in general practice that parents do not see childhood diseases as harmful to humans, in spite of possible complications, but as a biographical event with potential significance for their child's development. This view, based on feelings and experience, still needs scientific proof, but it would be disastrous if absence of proof were made the reason to ignore this definite opposition to the MMR immunization campaign when designing further campaigns.

Research in three particular areas supports the opponents' position.

Immunity as a learning process
The human immune system is, among other things, characterized by the ability to differentiate between self and non-self, learn from this and later use it specifically. The organism thus goes through a learning process as the immune system develops, the learning functions being recognition, memory and differentiation. The aim is to develop and maintain biological integrity. A popular notion is a "school for lymphocytes" in the thymus where immune cells acquire this ability.(6,7)

Learning processes of this kind essentially involve a need to come to terms, m the past, immunization happened "in the back yard." Modem hygiene made this disappear, and the result, initially positive, was that the incidence of many infectious diseases was reduced from the beginning of the 20th Century, drastically so in some cases. The immune deficiency diseases, lack of resistance, autoimmune diseases and allergies of recent times do, however, raise the question if efforts to prevent all infection have not gone too far.(8)

It is interesting that R. Schmidt noted as early as 1910 that, compared to the general population, cancer patients showed a remarkably low incidence of infectious diseases in their histories.(9) This was later confirmed, mainly by Sinek(10) and in a number of recent investigations.(11-14) With reference to mumps, it is significant that among 42 variables in the history, R. West found absence of mumps from the history to be the only significant correlation in a study of 97 patients with ovarian cancer in 1966.(15) His findings and those of E. Wynder et al.(16) were confirmed in a controlled retrospective study of 300 patients with ovarian cancer by M. Newhouse et al. in 1977.(17) A paper by L. McGowan et al. refers to a similar correlation, though this was not statistically significant.(18) Discussing childhood mumps, Newhouse ascribed the function of a "protective factor against ovarian cancer" to the disease, saying that it was to be expected that a virus affecting the ovary would increase the risk of tumor induction and that further work to confirm these findings would be of considerable interest.(17) This does not bear on causality, but the demand for further research should be taken seriously.

J. Kesselring reports similar findings for a link between multiple sclerosis and childhood diseases,(19) indicating how important it is for childhood diseases to be gone through at the right age.(20) According to Kesselring, systematic studies have shown that "the clinical impression that MS patients have often had their childhood diseases relatively late or not at all is supported by the significantly higher incidence of MS in individuals who had measles, mumps or rubella between the ages of 11 and 14." He referred to a study by E. Alvord et al. which showed that the relative risk of developing MS is four times higher in those who had mumps at the ages of 9-13 compared to 1-5.

None of the above data permits conclusions as to a causal relationship, but we have to ask ourselves if childhood diseases are not important "teachers" in the school of the immune system. It is evident that immunization cannot fully replace them. There is evidence, for instance, that the immune response following mumps immunization is both quantitatively and qualitatively inferior to that seen with the natural disease. IGA and IGM antibodies are fewer, with the complement binding reaction (CBR) reduced.(21) Immunization does induce a cellular immune response but not, for instance, poly-clonal B cell activation.(22)

Immunocompetence due to pyrexia
The (inverse) relationship between febrile infectious and chronic diseases, especially cancer, was certainly known to physicians who took careful histories in the past. Reports also exist on recovery from chronic diseases such as cancer following acute bacterial infections, e.g. erysipelas,(23) MS following chickenpox,(24) and of nephrotic syndrome treated with measles.(25-27)

It has long been suspected that pyrexia can prevent cancer.(28) A recent, controlled case study of 255 cancer patients by U. Abel has shown that a positive history as regards febrile infections in the preceding 5-10 years had a consistently high degree of correlation with reduced cancer risk-(13,14) According to our own recent study with 380 cancer patients and controls in 35 general practices in Switzerland, the febrile childhood diseases we are concerned with here show significant correlation with a reduced risk of developing cancer, except for breast cancer.(29)

There are, thus definite indications that our immune system needs the febrile diseases to achieve full immunocompetence. Temperatures in febrile range stimulate numerous functions of the immune system; work has been done especially on the interrelationships between interleukins, interferons and tumor necrosis factor.(30)

Immunity in ecological balance
For centuries, the microorganisms involved in childhood diseases such as mumps, measles and rubella showed a balanced relationship to the human population. Mass immunizations represent massive artificial intervention in those balances, with potentially unforeseeable consequences.

Epidemics are, above all, feared in populations where immunity to a particular pathogen has been lost because the disease has not occurred for some time. H. Stickl expressed concern even with regard to smallpox: "After the last case of smallpox, with the disease not recorded anywhere on earth for twice five years, which is the usual epidemic wavelength for smallpox, there was no longer any convincing reason for smallpox vaccination. Initially this was a great advantage. On careful reflection, it is evident, however, that in less than one generation an unvaccinated European population will reach the state which pertained prior to the great migrations of the 4th to 6th Century, i.e. before smallpox became endemic. People may then be expected to be completely receptive to smallpox virus infection.(31)

"Virgin soil" measles epidemics, i.e. peracute epidemics in areas with no natural incidence of the disease, are common experience. Examples are the epidemics on the Faroe Islands in 1946,(32) in Greenland in 1951,(33,34) Canada in 1952,(35) and New Guinea in 1960,(36) always with dramatically high incidence of complications and high mortality rates. Much the same has been noted in countries with enforced measles immunization programs. In Gambia, measles was said to have been eradicated in 1967, with 96% of the population immunized, but the disease broke out again in 1972, with the incidence of complications and the mortality rate increased.(37) Many similar, though smaller, outbreaks have been reported in the USA.(38-40) R. Philip describes a "virgin soil" mumps epidemic among 561 Eskimos on St. Lawrence Island in 1957, with increased incidence of orchitis and abortions.(41)

One direct consequence of the mumps immunization campaign is a shift of the infection to adolescence and adulthood on one hand, and early infancy on the other. In adolescents and adults the rate of complications is higher with mumps than with measles and rubella.(42) In the USA, the MMR immunization campaign caused the incidence of mumps in people over the age of 15 to rise from 12% in 1977 to 38% in 1989.(43) It remains to be seen if mumps immunization also increases the risk for infants; in the case of measles, insoluble immunization strategy problems are already known to exist.

Fundamentally new problems may also be expected, especially as regards the administration of multiple live virus vaccines over complete areas. Diseases due to virus mutation have been reported, e.g. following hepatitis B vaccination,(44) the use of recombinant viruses such as polio vaccination,(45) or the adaptation of animal viruses to humans following eradication of the relevant human virus, as in smallpox.(31) Further problems will emerge with vaccines produced by genetic engineering; S. Oethen et al. showed that vaccines such as these can have such an unfavorable effect on the balance between virus and immune defenses that a disease will be enhanced rather than weakened.(46)

In view of such observations, J. Lederberg, who won the Nobel Prize for his work on bacterial augmentation in 1990, suggests that we have to expect further "major disasters" such as AIDS because there is too much intervention in the natural relationship between humans and viruses.(47)

Mumps immunization failure invites reflection
The main problems with mumps immunization in Switzerland today may be relatively harmless; in a wider context they do, however, point to central problems with the immunization campaign.

Mumps immunization was included in the Swiss MMR immunization package in 1987 for the following reasons:(48)

a - Mumps is to be eradicated in Switzerland and surrounding countries by the end of this century.
b - A good vaccine is available, and there are no problems in giving it together with the measles and rubella vaccines, so that inclusion of this disease in a broadly-based elimination program also makes sense from the cost-benefit point of view.
c - All the currently-used vaccines are attenuated, live vaccines and confer immunity in more than 95% of those vaccinated. Protection may be assumed to be life-long following a single immunization with all three vaccines.
d - Apart from parotitis, which is rare and always harmless, no serious
complications are known with mumps immunization.
e - Failure to immunize the whole population may cause the disease to develop at a later age. It is therefore important to achieve as high an immunization rate as possible, as early as possible in childhood.

Analysis of the mumps epidemiology seven years later shows the following:

Regarding a: according to Sentinella, recorded incidence of mumps decreased slightly from 1987 to 1989 but has definitely increased since then. 0.7 reports were received per physician in 1989/90, 2.6 in 1991/92 and 3.3 in 1993 (records for June-December, extrapolated to cover one year).(49)

Tschumper and T. Abelin have since found that mumps cannot be eradicated in Switzerland. "Today, the eradication of measles, mumps and rubella actually appears to be a goal that cannot be realized... Such high immunization rates would be difficult to achieve without making immunization compulsory... The reason for recommending MMR immunization at the age of 15-24 months is, however, the protection conferred on the individual."(42)

This puts the rational basis of the mumps eradication campaign in doubt both theoretically and empirically.

Regarding b: the increased mumps incidence in Switzerland, following the low point reached in 1989, suggests that the immunization is not fully effective.(50) Vaccines still on the market are generally said to be 80% effective.(51) A more effective vaccine prepared from the Urabe strain had to be withdrawn because of side effects (v.i.).

Regarding c: these observations also cast doubt on the hypothesis that protection is for life. For this reason - and to ensure first-time failures are covered - a repeat MMR immunization is now demanded.(52) The efficacy of booster mumps immunization is far from certain, however. In the case of rubella, indications are that the booster effect is inadequate.(53)

Regarding d: the unexpected increase in meningitis following vaccination(54) that in 1992 led to the withdrawal of vaccines containing the Urabe strain confirms that people may indeed have a false sense of security concerning complications due to mumps immunization.

Regarding e: figures concerning the level of immunization differ greatly from canton to canton. The figures given for immunization of 3-year-olds in the canton Bern were 68% for 1989 and 66% for 1992.(55,56) From 1987 to 1990, the mean percentage of the 11,000-20,000 children starting school in 8-12 cantons was almost consistently found to be 85, the range between cantons being 67-97.(57) Parents' active refusal to have their children immunized rose from 6.3% to 10%. In 1991, 80.1% of 402 children aged 27-36 months in all parts of Switzerland had been immunized against mumps.(58) The figures for young children in neighboring countries, reported at the 1993 EPI meeting, were 70% (Germany), 64% (France) and 35% (Austria). No figures were given for Italy.(59)

This means that immunization is currently at the low level experts always consider to be particularly dangerous. Whether repeat immunization would change the situation has to remain a hypothetical question.

Long-term epidemiological effect
The "failure," as it may be seen, of mumps immunization, which is to be overcome by intensifying the immunization campaign, points to central inconsistencies in the whole campaign. The eradication project has proved highly susceptible to breakdown and goes against modem views of long-term efficacy." With only 80%, rather than the necessary 95%, of the population agreeing to be immunized, and with the efficacy of the vaccine at 80%, rather than the expected 90%, the campaign is turning into a dangerous experiment.

In the USA, mumps immunization of the population initially resulted in an impressive 98% reduction in incidence, reaching a record low of 21,982 recorded cases in 1985. Since then, however, the incidence has risen again, with a shift to adolescence and adulthood. In 1989, 38% of reported cases were in people over the age of 15, compared to 12% in 1977.43 The reason given is problems with supplying the vaccine. The same problem is found with measles immunization in the USA.(61,62)

This susceptibility to failure means that enforced measures become increasingly necessary to limit relapse epidemics. They include ensuring and maintaining immunization of the whole population, monitoring the immunity of the population, and monitoring virus circulation on borders and in quarantine situations, as well as barrier immunization procedures to limit outbreaks.

Political compatibility
Both physicians and parents would be against enforcing the higher level of compliance needed to continue the campaign. This would mean imposing government views on the Swiss health system when there is no need from the public health point of view. Constitutional lawyers doubt, however, that the limitation of basic rights in such an enforced measure would meet the requirements of suitability and reasonability.(63)

Another problem with the perceived failure of mumps immunization is that, when an immunization that is fundamentally unnecessary shows poor efficacy and the incidence of complications increases, it is apt to affect people's confidence in immunization altogether, also casting doubt on other procedures such as tetanus and polio immunization.

It is evident, therefore, that limited MMR immunization is needed, not only giving positive results in the short term but also taking account of the need for epidemiological and ecological long-term effects and political acceptance, m the case of mumps, selective immunization of school leavers found to have no immunity might be the most suitable approach, the aim being to avoid post-puberty complications; this is also the method repeatedly requested for rubella.(64,65)

In conclusion, let me quote the words of J. Dausset, who won the Nobel Prize for discovering the HLA system, the human leukocyte Group A antigens that may be said to establish human individuality at molecular level:

La vaccination des enfants contre toute une serie de maladies pourait bientot etre une pratique du posse... Les Vaccins ne seront alors administres que pour des maladies a risque elevee. Nous sommes a la veille d'une nouvelle epoque ou chacun recevra un traitment personnalise.

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