LIVE POLIO IRUS VACCINES

Vaccination with CHAT Strain Type 1 Polio Virus in Leopoldville 467
TABLE 1. POPULATION AND VACCINATION STATISTICS, LEOPOLDVILLE AFRICAN CHILDREN 6 MONTHS
TO 2 YEARS OLD (IN THOUSANDS)
AVERAGE POPULATION
VACCINEES
AREA OF CITY
1958
1959
30 APRIL
1959
30 APRIL
1960
Ancienne Cité
Nouvelle Cité
Five Districts
13.5
15.1
12.0
14.7
15.6
15.9
10.7
7.0
7.9
13.6
12.4
15.4
All
40.6 46.2
25.6 41.4
TABLE 2.
REPORTED CASES OF PARALYTIC POLIOMYELITIS BY MONTH, JANUARY 1958 THROUGH APRIL
1960 AND BY VACCINATION STATUS
Reported Cases Each Month: Vaccinated Cases in
Parentheses
YEAR JAN. FEB. MAR. APR. MAY JUNE JULY AUG. SEPT. OCT. NOV. DEC.
1958
1959
1960
12 5 6 1 2 0 1 0 1
(-)* (-)
24 15 9 1 5 6 10 9 7
(3) (2) (4) (-) (1) (1) (4) (5) (3)
4
(1)
6
(3)
6 3
(1) (-)
3
(-)
8
(4)
9
(1)
6
(3)
37
(-)
6
(3)
* Vaccination began in August, 1958.
TABLE 3. AGE DISTRIBUTION OF PARALYTIC POLIOMYELITIS IN AFRICAN CHILDREN, LEOPOLDVILLE,
SINCE BEGINNING OF VACCINATION
AGE IN YEARS
AUG. '58-APR. '59 MAY '59- APR. '60
NUMBER PER CENT NUMBER PER CENT
3
25
57
15
1
1
25
58
15
1
1
3
14
37
16
4
2
4
18
49
21
5
3
Total 99 100 76 100
virus and also by the residential area and vaccination
status of the individual from whom the
virus was isolated. Seventeen Type 3 isolations
were made during May to December 1959, as
well as five Type l's, five Type 2's, and six nonpolio
viruses. Fifteen viruses were isolated from
vaccinated individuals, of which 10 were Type 3.
Eighteen viruses were isolated from non-vaccinated
individuals, of which seven were Type 3.
From these data it is clear that there has been