TYPHOID FEVER.

WIDAL, AGGLUTINATIVE OR SERUM TEST.

During the year ended Nov. 30, 1909, the Widal test was carried out with 830 specimens of blood. Of these specimens, 54, or 6.5 per cent., gave a positive reaction. Specimens were sent in from 121 cities or towns. These facts are shown in detail in Table I. In a second table (Table II.) the specimens, positive and negative, are classified according to the day of the disease on which they were collected. A moderate number of second and third specimens from the same case were examined, so that the total number of tests made is somewhat over the number of cases of disease concerned. The methods used during the year were the same as those previously in use in the laboratory, and they have been amply described in the reports of the year 1900 and the years following.

TABLE I. Widal Test, Dec. 1, 1908, to Nov. 30, 1909, inclusive, classified according to the City or Town from which the Specimen was sent.

Posi- Nega-
tive. tive.

TABLE II.-Widal Test, according to Stage of Disease, Dec. 1, 1908, to Nov. 30,

APPROXIMATE NUMBER OF

DAYS FROM BEGINNING

OF DISEASE TO COLLECTION OF BLOOD.

1909, inclusive.

NUMBER OF
CASES.