40
Infection indices in chawl B showing seasonal incidence and intensity.
Serial No
Date of observation
Number examined
Number infected
Percentage infected
Average number of parasites per 150 fields
1
23rd June 1909 ...
150
60
40.0
15.9
2
2nd August " .....
95*
30
31.6
17.4
3
9th November " .....
103*
45
43.6
4.4
4
7th May 1910 ...
75
16
213
4.0
5
11th June " ...
51
8
15.7
7.1
6
11th July "
42
8
19.0
2.7
7
30th August "
50
12
24.0
5.8
8
5th October "
64
20
31.2
6.4
* Many residents receiving quinine. Observations made by a different observer.
88. Chawl A was composed of lines of single storied huts built of
corrugated iron and provided with roomy open verandahs in which many of the
people used to sleep. An inspector visited this chawl daily and it was kept in
a very clean and orderly condition. Chawl B was composed of three two-storied
blocks of back to back tenements, dark, filthy and overcrowded. These tenements
were provided with a very narrow landing or verandah which the tenants
mostly shut in with matting. The windows also were all stopped up with
paper and rags. It appears probable that anopheles mosquitoes obtained access
to chawl A with much greater ease than to chawl B on account of the open site
of the former chawl and the fact that windows and verandahs were not allowed
to be closed in as in chawl B. A considerable portion of the inmates of both
these chawls were in receipt of quinine treatment from the middle of August to
December 1909. During 1910 they got no treatment.
89. The ten different occasions upon which bloods were examined from
A chawl showed a varying percentage of light and heavy infection.




A Chawl.
Serial number
Month
Percentage of infections showing under10 parasites in 150 micros- copic fields.
Percentage
of infections showing over100 parasites
in 150 micros- copic fields.
1
June 1909 ... ...
54.6
10.3
2
September " ... ...
67.7
11.7
3
December " ... ...
833
...
4
April 1910 ....
100.0
...
5
" " ......
83.3
...
6
June
62-5
6.2
7
July " ...
81.8
4.5
8
August " ......
45.0
10.0
9
October " ... ...
64.2
3.5
10
December " ...
68.9
...
B Chawl.
1
January 1909
70.0
5.0
2
August " ...
63.5
6.6
3
November " ...
97.7
...
4
May 1910 .
93.7
...
5
June " ...
75.0
...
6
July " ...
*100.0
...
7
August " .
*75.0
...
8
October " .....
*90.0
...
*Observations made by a different observer.