﻿OBSERVATIONS UPON FILARIA PHILIPPINENSIS. 



Periodicity. — Filaria philippinensis presents no periodicity as regards 

 the time of its appearance in the peripheral blood or the number of 

 embryos present at any one time. We have made extensive observations 

 regarding periodicity in all five cases of infection with this filaria and can 

 state conclusively that it can be found in the peripheral blood at all 

 hours of the day and night and in practically the same numbers at all 

 hours. The following table, which gives the results of examinations made 

 every three hours during the twenty-four, demonstrates the lack of 

 periodicity in Filaria philippinensis : 



Case number 1. 



Number in individual counts. 



7 a. in., 3 filarise in 3 blood smears. 

 10 a. m., 2 filaria; in 3 blood smears. 



1 p. m., 2 filarial in. 3 blood smears. 



4 p. m., 1 filaria in 3 blood smears. 



7 p. m., 2 filarial in 3 blood smears. 

 10 p. m., 1 filaria in 3 blood smears. 



1 a. m., 3 filarise in 4 blood smears. 



4 a. m., 2 filarise in 3 blood smears. 



Average per day and night. 



7 a. m. to 7 p. m., 8 filarise 



in 12 smears. 

 7 p. m. to 7 a. in., 8 filarise 



in 13 smears. 



Case number 2. 



Number in individual counts. 



7 a. m., 5 filarise in 3 blood smears. 

 10 a. m., 1 filaria in 4 blood smears. 



1 p. m.j 1 filaria in 3 blood smears. 



4 p. m., 1 filaria in 3 blood smears. 



7 p. m., 2 filarial in 3 blood smears. 

 10 p. m.j 3 filarise in 3 blood smears. 



1 a. m.j filaria in 3 blood smears. 



4 a. m., 3 filarise in 4 blood smears. 



Average per day and night. 



7 a. m. to 7 p. m., 8 filarise 



in 13 smears. 

 7 p. in. to 7 a. m., 8 filarise 



in 13 smears. 



Case number 3. 



Number in individual counts. 



7 a. m., 2 filarise in 3 blood smears. 

 10 a. m., 1 filaria in 4 blood smears. 



1 p. m., 3 filarise in 3 blood smears. 



4 p. m., 2 filarial in 3 blood smears. 



7 p. m., 4 filaria; in 3 blood smears. 

 10 p. m., filaria in 3 blood smears. 



1 a. m., 5 filarise in 4 blood smears. 



4 a. m., 1 filaria in 3 blood smears. 



Average per day and night. 



7 a. m. to 7 p. m.. 8 filarije 



in 3 smears. 

 7 p. m. to 7 a. m., 10 filaria; 



iii 13 smears. 



A study of the above table will show that at no definite time during the 

 twenty-four hours can the filarial be said to be numerous enough to be 

 characteristic of that time, and that no difference exists in the number 

 observed in the peripheral blood during day and night. This fact, 

 together with the presence of a sheath in Filaria philippinensis, serves to 

 differentiate it from any other filaria which has been described as infecting 

 man. It should be noted that it occurs in small numbers at all times 



