LIVE POLIO IRUS VACCINES

Live Poliomyelitis Vaccine-Small-Scale Trial in Isolated Island Community 535
poliovirus was used and administered in capsules
containing 105 tissue-culture doses of virus.
For the second part of the trial all the three
types of poliovirus were used. In this case 1 ml.
of a fluid vaccine containing approximately 106
tissue-culture doses per ml. of each type was
given mixed in about 10 ml. of plain water.
Plan of the Trial
The trial was initiated in January 1958. The
immunity status of the population was determined
before the start of the trial, and the entire
population received two injections of inactivated
poliovirus vaccine at three-week intervals. One
ml. doses of vaccine were given intramuscularly.
Six weeks after the second vaccination, blood
and stool samples were collected from the population,
and 10 families from different parts of
the island comprising 43 persons or about 20
per cent of the population were given live Type
1 poliovirus vaccine. Six and 12 weeks later
blood and stool samples were collected from the
whole population. In March 1959 blood samples
island is visited only once a month by a local
doctor from the neighboring island, except in
emergency cases. Between visits a specially
trained nurse is responsible for medical care
on the island. During the period in question
the entire population was medically examined
six times by one of the authors, and the nurse
was asked to make careful notes about any
signs of infections which might occur in the
community. Thus, practically all illnesses were
recorded although few of the patients were
examined by a doctor except on the occasions
mentioned above.
Close contact was kept with the central hospital
on the main island. Stool samples from
all patients with central nervous system symptoms
were tested for the probable presence of
poliovirus and in some cases for Coxsackie.
Sera were examined for the presence of polio
and RSSE antibodies.
Collection of Specimens
It was not possible to obtain specimens from
TABLE 1.
TIME SCHEDULE FOR THE SOTTUNGA TRIALS
Date Approximate Type of Type of Scepi-
Interval Vaccine mens Collected
in Weeks !
1958 January Inactivated Blood
3
February
Inactivated
7
April Live type 1 Blood, etool
6
May - Blood, stool
6
July - Blood, stool
1959 March Live type 2 Blood, stool
4
April Live type 1
May Live type 3
6
June - Blood, stool
were again collected from the population and
the second part of the trial was begun by feeding
the whole population all three types of the
vaccine as described above at four-week intervals
and in the following order: Type 2, Type 1,
and Type 3. About six weeks after the last
feeding, blood and stool samples were again
collected and the trial finished (Table 1).
Control Measures: Because of its location the
the entire population (the absence of some persons
during the days of sampling, transportation
difficulties, and similar), and thus at every
sampling only about 90 per cent of the specimens
were obtained, altogether 1,280 sera and
1,049 stool samples.
Blood specimens were collected in venules and
kept at room temperature for one or two days
and thereafter for one or two days in the re-