제주도의 絲狀蟲症에 관한 연구

Abstract

A considerable amount of work has been done regarding the filarial worm in Korea,

since Yoon(1927) found one male filaria from the left inguinal lymph gland by

autopsy of one case with elephantiasis of both legs. although Yoon(1927) identified

the parasite as Wuchereria bancrofti without any morphological study, it is the

general opinion that Brugia malayi is generally recognized as the only species of

human filaria in Korea. The malayan filaria is distributed predominantly in Cheju

Island and its neighbouring islands, though several areas in the mainland also show

endemicity.(Oh, 1929; Oh, 1930; Bun, 1939; Senoo, 1943; Hunter et al.. 1949; Paik,

1959; Lee et al., 1964; Hwang et al., 1965; Soh et al., 1966 and Seo et al., 1968

etc.).

The present study was designed to elucidate the epidemiological and clinical

features o B. malayi infection in Cheju Island.

As the subjects, 981 students of Seogi Agricultural High School and Seogi Girl's

High School(male, 257; female, 724) at Seogipo-Up(=town) were sampled in May, 1970.

For the second step, samples were drawn among 521 students of Namwon Junior High

School(male, 302; female, 219) and 164 school children(male, 97; female, 67) of

Wimi Primary School located together at Namwon-Myun(=township), where high positive

rates were calculated from the above survey at Seogipo-Up.

Seven elephantiasis cases and six control inhabitants besides the students were

also selected for some physiological investigation.

The students gathered voluntarily at the period of 21:00∼23:00 hours. Three

drops of blood from the examinees' finger tip were obtained by lancet to make the

thick smear preparations on the clean, fat free slide glasses. The dried smears

were brought to the laboratory, and microscopic examination of the dried blood

smears were done after staining with Giemsa solution to detect the microfilariae.

The environmental condition survey in the endemic areas was done with a

questionnaire designed by the author. Fifty-three microfilariasis cases(male, 34;

female, 19) and 47 control students(male 30; female, 17) of Namwon Junior High

School were complied with this schedule.

Physical measurement of body length by Martin's anthropometer(Super Co.), body

weight by the portable weight balance, hand grip by Hand Grip Dynamometer(TKK), and

back lift strength by Back Dynamometer(TKK) were examined with the ordinary

methods.

All the examinees took a good rest, seated 30 minutes before the test. After the

number of heart beats and blood pressure of the examinees were checked by pulse

meter(Heartpet HR-7A, Mitsubishi Electric Co.) and sphygomomanometer. The examinees

exercised, practicing up and down the wooden box of 30cm height 5 minutes at the

speed of 30 times in a minute. After the loading, the frequency of heart beat was

measured by pulse meter with a minute interval. The increasing pulse and recovery

rate of each test were calculated by the following formula:

Increasing pulse=(Pulse immediately after H.S.T.)/(Resting pulse)×100

H.S.T.: Harvard Step-up Test

Recovery rate=(Step for 5 mins(30×5')×300(30cm.))/(Total pulse at 1's+2's+3)

All the examinees rested in the seat for 30 minutes before blood flow test. In

the resting situation, a sphygmomanometer was fixed on the examinee's thigh to

check the blood flow, and then Whitney's strain gauge for volume estimation of

blood flow(ml/min/100gm tissue) was settled on the lower leg, respectively. All of

the records were indicated on the dynograph(Beckman RS Type) by the perception of

strain gauge plethysmograph.

After measuring the arterial blood flow in succession of venous occlusion(50mmHg)

at the resting period, arterial blood flow was occluded under 200mmHg pressure for

5 minutes. The first check of the arterial blood flow was performed immediately

after reactive hyperemia(0' sec.), sustaining the venous occlusion. Five minutes

after the first check, it was checked at 30 second intervals for 5 minutes and then

continued at one minute interval for next 5 minutes. Up to 10th minute, the values

detected in this test were calculated by the routine formula of blood flow test.

For intelligence test standard questionnaire from which was published at the

Institute of Educational Psychology, College of Education, Seoul National

University was used. Serum protein was measured by rapid electrophoresis using

sepraphore Ⅲ strip. Differential leukocyte count was done routinely Wright stain

of thin blood smears. In the study of bacterial infection blood agar plate and

thioglycollate broth media were used in culture for identification of bacteria.

During the summer season(July-August) 1969, the insecticide tests for resistance

on adults and larvae of Aedes togoi were carried out. Aedes togoi larvae were

collected from the breeding places, tidewater rock pools in endemic area of

filariasis in Cheju-Do, and adults in the test were bred in laboratory from the

larvae. WHO standard method for insecticide resistance test on adults and larvae of

mosquitoes(1963) was applied.

The results were as follows: Eight out of 257 male students of Seogi Agricultural

High School were microfilarial positives(3.1%). the students from Namwon-Myun, one

of the high end endemic focus, revealed the highest prevalence(10.3%), and the

positive cases among these students were the residents mostly in

Wimi-Ri(Ri-village), Namwon-Ri and Taeheung-Ri located along the coastal area in

Namwon-Myun. Out of 724 blood smears in Seogi Girl's High School, only 6(0.8%) were

positive, and all of those were from Bupwhan-Ri, Hokeun-Ri in Seogipo-Up and

Wimi-Ri in Namwon-Myun.

Out of 521 students of Namwon Junior High School, the prevalence of the

microfilariae was 10.9%(male, 12.3%; female, 9.1%). The positive rates were 10.2%

in Taecheung-Ri, 26.8% in Wimi-Ri, 9.4% in Namwon-Ri and 8.2% in Shinheung-Ri, and

all of them were located lining the coastal area; but none of the students who

inhabited the mountainous are showed positive.

The positive rate among 164 children in the fifth and sixth year grade of Wimi

Primary School was 19.5%(male, 16.5%; female, 23.9%). The highest positive

rate(22.8%) was found among the children resided at one out of 6 villages, Wimi-Ri,

where the parasite has been highly prevalent.

As a preliminary check to detect endemic foci of filariasis in a wide area the

rusult of a night blood survey on children and students in school might be valuable

for extensive practical field work on filariasis among general population.

One hundred students of Namwon Junior High School(male, 64; female, 36) were

subjected for the survey by questionnaire. In average, the family members of each

household were 7.1 in the filariasis group(male, 30; female, 17) and 6.6 in the

non-filariasis group(male, 30; female, 17). The numbers of the households in which

the examinees dwelt more than 10 years in Cheju Island were 47(86.8%) in the

filariasis group and 40(85.1%) in the non-filariasis group.

Thirty-three households(62%) of the filariasis group were located within 500

meter area from the coastal line, and 15(31.9%) of the non-filariasis group.

Elephantiasis patients were found in 18(33.9%) out of 53 households of filariasis

students and in 8(17.0%) out of 47 households of the non-infected group.

Fourteen out of 36 students(38.9%) misunderstood that elephantiasis was due to

drink unsuitable water, and the students who gave the right answer about the vector

of the filarial parasite were only 15%.

Height and weight of the body, hand grip and back lift strength of the students

aging 10 to 15 years were measured. The examinees were 80 students in both infected

and non-infected group, respectively. Height and weight in 13 year-old and 15

year-old male students of the infected group showed a slight decrease as compared

with the non-infected group, but no difference was observed in female groups. The

mean values of the hand grip power between two groups were compared. The mean

values of back lift strength in the filariasis students were 63.8kg in 10 year-old

male group and 36.0kg in 11 year-old female group, whereas the values in healthy

were 50.8kg and 44.2kg in the same age group. The hand grip and back lift strength

tended to decrease significantly in the filariasis cases. Some physical

examinations with special reference to Harvard Step-up Test were carried out in the

11 to 17 year-old students. the blood pressure(systolic and diastolic) and pulse

were not different in the infected and non-infected students at the resting state.

The pulse recovery rates after taking exercise by Harvard Step-up Test were

156.5(male) and 152.5(female) in the filariasis cases in contrast to 171.7(male)

and 164.5(female) in non-filariasis group. In the same test, the values of

increasing pulse were 176.8(male) and 179.6(female) in filariasis cases, but

169.2(male) and 161.8(female) in non-filariasis group.

A 69 year-old female elephantiasis case who suffered from cuticular hypertrophy

in right lower leg showed greater delayed recovery of arterial blood flow following

reactive hyperemia in the elephantiasic leg than in the healthy side. In spite of

taking time immediately after reactive hyperemia, the slope of blood flow curves on

the dynograph was more precipitous in the swelling leg that in the control one. In

comparison of blood flow following time in minutes among 7 elephantiasis cases and

6 control healthy, the increased of blood flow immediately after reactive hyperemia

was more significant in healthy group(p-value<0.05), whereas the recovery of blood

flow by time delayed in the elephantiasis group. In the result of intelligence test

for the students of Namwon Junior High School there was no significant difference

between filariasis and healthy group.

In comparison of serum protein of 4 elephantiasis cases and 2 control persons,

measured by rapid electrophoresis, lower gamma-globulin values and higher A/G ratio

were observed in elephantiasis group. Clinical manifestation of 32 elephantiasis

cases aged 13 to 79 yeats were surveyed. The site of cuticular hypertrophy in

elephantiasis cases was 84.4% in the lower extremities and 15.6% in the upper

extremities; however, no case was observed in the upper extremity only.

The symptoms were mainly occasional fever, chilling, headache, pain and lumbago

in decreasing order. Skin injury and hard labour were recognized as the motives for

those symptoms. All elephantiasis cases complained the labour difficulty during the

sickness.

The range of eosinophilic leukcocytes was 1∼13% in the elephantiasis cases and

1∼10% in the filariasis cases. Bacterial infection at the location accompanied

with acute inflammation was proved in 9 elephantiasis cases. Staphylococcus in 4

cases and Gram negative bacilli in 5 cases were detected.

Insecticide susceptibility tests of both adults and larvae of Aedes togoi were

perform to elucidate preventive measures in the future. The mortality rates of

Aedes togoi larvae were 67.6% in 0.5ppm and 100% in 2.5ppm of DDT., and LC^^50 was

0.085ppm. By BBC LC^^50 was 0.078ppm and by Dieldrin LC^^50 was 0.0075ppm.

The 3 day-old adults of Aedes togoi showed mortality rate of 88.7% in 4% DDT and

LC^^50 was 2.2%.

Summarizing above results:

1. Among 521 students of Namwon Junior High School, the prevalence of the

microfilariae of Brugia malayi detected in the blood smears was 10.9%(male, 12.3%;

female, 9.1%). The positive rates according to the villages of these students'

residence showed 10.2% in Taecheung-Ri and 26.8% in Wimi-Ri which were located

together along the coastal area, but one of the students resided in the mountainous

area showed positive.

2. The positive rate of malayan microfilariae among 164 children, resides at 6

villages, of Wimi Primary School(5th and 6 th year grade) was 19.5%. Highest

rate(22.8%) was found in children resided at Wimi-Ri where has been known as the

high endemic focus of the parasite in Cheju-Do.

3. The students who gave the right answer to the questions regarding the vector

of the filaria were no more than 15%.

4. In comparison of height and weight of the body, hand grip and back life

strength measurements between filariasis and non-filariasis students in this study;

the filariasis group was inferior to the control, especially in hand grip and back

lift strength test.

5. The pulse recovery after taking exercise by Harvard Step-up test delayed more

in the filariasis cases than in the healthy controls.

6. In an elephantiasis case, the normal recovery of blood flow in accordance with

the reactive hyperemia was delayed more in the elephantiasic leg that in the normal

leg. Among 7 elephantiasis cases and 6 healthy persons, the increase of blood flow

immediately after reactive hyperemia was more faster in the healthy group, whereas

the recovery of blood flow by time delayed in the elephantiasis.

7. The intelligence test for the students of Namwon Junior High School showed no

difference between the filariasis and the healthy group.

8. The total serum protein level were increased more in the elephantiasis cases

than in the healthy controls. Albumin-globulin ratio in the elephantiasis patients

was 0.66 in average.

9. the site of cuticular hypertrophy in elephantiasis cases was 84.4% on the

lower extremities and 15.6% on the upper extremities.

10. The principal clinical manifestations were occasional fever, chilling,

headache, muscle pain and lumbar pain in decreasing order.(skin injury and hard

labour were recognized as the motives for those symptoms).

11. Elephantiasis patients complained of working difficulty during clinical

manifestation.

12. Eosinophil leukocytes were 1∼13% in the elephantiasis cases and 1∼10 in the

microfilariasis cases.

13. Various microorganisms were detected from the inflammed portion of

elephantiasis.

14. Both adults and larvae of Aedes togoi showed susceptibility to the

insecticides DDT, Dieldrin and BHC.