Læknablaðið - 15.01.2005, Page 101

1 975-1 984 / BERKLAVEIKI
and morbidity rates are from then on the best measures of the preva-
lence and course of the disease.
Tuberculosis infection-rates obtained through tuberculin testing on
a comparatively broad scale, especially in school children 7-13 years of
age, show a progressive reduction in tuberculosis infection in the coun-
try as a whole. These tuberculin surves on school children were initiated
by the district health officers in the second decade of the century and
therefore now extend over 60 years. The procedure of the tuberculin
surveys and the methods used are mentioned. The shortcomings of
these surveys and their importance are discussed. The value of the sur-
veys is considered doubtful as long as the examinations are performed
without any guidance or coordination. About the year 1930 the total
percentage tuberculin tested in the age group 7-13 years was a little
over 10 percent. In the year 1935 the director of tuberculosis control
sent all the health officers instructions on how to perform the tuberculin
testing together with some encouragement to perform such surveys.
That year about 43 percent of the 7-13 years population was tested and
in 1945 the percentage was 75. Between 1965 and 1970 the attendance
percentage was 85.
The tested 7-13 years age group showed in 1935 26.1 percent
positive reaction, in 1945 10.1 percent, in 1955 5.3 percent and in 1970
0.7 percent. In 1970 0.2 percent of the 7 years old children reacted
positively and 1.1 percent of those 13 years of age. the decline of the
infection rate in this age group is remarkable. The very few BCG vac-
cinated children were excluded from the surveys.
In the tuberculosis surveys made in the years 1940-1945, which
covered 12 medical districts or parts thereof, extensive tuberculin
examinations were performed. The results of these surveys showed
that the infection rate was higher among male adults than females. This
difference was notable after the age of 15 and especially in isolated and
thinly populated rural districts. In urban and more thickly populated rural
districts the infection rate was much higher.
BCG vaccination was first used in lceland in 1945. Only few persons
were vaccinated in the first two years. In 1948 a systematic vaccination
was proposed in the country to supplement the tuberculosis-control
plan. The vaccination was particularly meant for the age group 12-29
where the risk of infection appeared to be greatest. However, at the end
of the year 1950 a total of only about 6,900 persons had been vac-
cinated mostly groups of school children, young adults and contacts of
tuberculosis cases. Most of the children and adults were born between
the years 1929 and 1936 but in none of these years did the vaccination
exceed 15 percent of those born in any one of the years concerned.
Because of the rapid decline in the tuberculosis infection rate, morbid-
ity and mortality in the country this vaccination plan was abandoned
and changed at the end of the year 1950. After that only few groups of
people were vaccinated, i.e. tuberculosis contacts, medical students,
student nurses, adults studying abroad and persons who asked for
vaccination.
Between 1950 and 1970 only about 7,000 people have been vac-
cinated. So the total number of BCG vaccinations up to the end of 1970
has not exceeded 14,000 in the country. Therefore it seems most un-
likely that the relatively few BCG vaccinations, given in recent years can
be expected to have had much influence in speeding up the downward
trend of the disease in the country. A careful record has been kept of the
vaccinations performed.
Examinations (tuberculin tests, microscopic examinations and cul-
tures) have been made by veterinary surgeons and physicians on cattle,
sheep and fowl. According to their findings tuberculosis is very rare in
domestic animals.
The bovine type of tuberculosis has never been found with certainty
either in human beings or in cattle. On the other hand the avian type has
been found in fowl as well as sheep. Tuberculous infection (based on
positive tuberculin tests and positive avian cultures) found in cattle may
perhaps also be of human origin although not stated.
Mention is made of the fact that mycobacteria other than mycobac-
terium tuberculosis have been noted during the tuberculin testing in the
country. This is a rare and local phenomenon which happens mostly in
the neighbourhood of warm swimming pools. Mycobacterium balnei
was considered to be the agent.
The medical profession of the country is urged to remain alert to the
disease even if it is becoming rare. Tuberculin testing should be used
widely, especially among children and young adults. Since lceland has
mostly refrained from BCG vaccination the positive tuberculin reaction
has com to be of great diagnostic value. Thorough instruction must be
given to those concerned with the tuberculin testing procedure and its
interpretation. It is also of great importance in the tuberculin negative
community to track down the open case as soon as possible. Such a
patient must receive adequate treatment and be kept in isolation as long
as he remains contagious. Careful follow up is necessary in all such
cases as well as those freshly infected persons who may have received
secondary chemoprophylaxis.
BCG vaccination should be offered to groups sucha as medical stu-
dents, student nurses and children and young adults living with people
who have had tuberculosis.
Use of secondary chemoprophylaxis is in many cases advisable but
primary chemoprophylkaxis should only be used when there is very
strong suspicion of infection in spite of negative results of repeated and
adequately performed tuberculin testing.
The possibility of complete eradication of the disease from the coun-
try is dicussed. The unusually rapid decline in the tuberculosis infection
rate, morbidity and mortality during the last decades are tempting
facts for such thoughts. In order for such an eradication to take place
transmission of tuberculosis from open cases must be prevented to the
utmost in order to constantly reduce the infection rate and thereby the
number of carriers. Furthermore immunological factors and living condi-
tions are of great importance in the community concerned.
Tuberculosis is still a great propblem in many countries. With ever
growing international communications complete eradication of tuber-
culosis is a worldwide project and can hardly be achieved by any single
country. Thus eradication is not likely to be achieved in the near future
although it should be constantly strived for.
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