Rev. Soc. Bras. Med. Trop. vol.22 número4

R e v i s t a d a S o c i e d a d e B r a s i l e i r a d e M e d i c i n a T r o p i c a l 2 2 ( 4 ) : 1 8 7 - 1 9 0 , O u t - D e z , 1 9 8 9 .

E N V I R O N M E N T A L C O N T A M I N A T I O N B Y

T O X O C A R A S P

E G G S I N

P U B L I C A R E A S O F S A L V A D O R , B A H I A S T A T E , B R A Z I L

Neuza Alcântara1 4, Emilia Bavia2, Rose Mary Silvão4 and Elza Carvalho1 3

A s u r v e y o f p a r a s i t e e g g s a n d c y s t s i n s o i l a n d d o g f e c e s c o l l e c t e d i n p u b l i c p l a c e s

o f 2 3 b o r o u g h s o f S a l v a d o r , a c i t y i n t h e N o r t h e a s t o f B r a z i l , w a s p e r f o r m e d . H i g h d e g r e e o f c o n t a m i n a t i o n b y

Toxocara sp

p a r a s i t e s f o u n d i n c l u d e d :

Ascaris lumbricoides,

c y s t s . P a r k s a n d p u b l i c g a r d e n s w e r e m o r e c o n t a m i n a t e d t h a n s t r e e t s a n d b e a c h e s f o r a l l

p a r a s i t e s , i n c l u d i n g

Toxocara sp.

K e y - w o r d s :

Toxocara sp. Ascaris lumbricoides.

T o x o c a r a c a n i s

and

are animal

ascarids which accidentally infect man without com­

pleting their life cycle. The former is the most common

agent of visceral larva migrans (VLM), a disease

occuring during childhood and leading to clinical

manifestations such as liver and spleen enlargement,

fever and persistent hypereosinophilia^ I

7

19

Visceral larva migrans has a worldwide distri­

bution, the largest number of cases reported from

developed countries probabily indicates better dia­

gnostic conditions than higher prevalences. The en­

zyme-linked immunoassay technique using as antigen

T o x o c a r a

larvae secretory-excretory products, deve­

loped on the seventies

7

8

has facilitated the diagnosis

of VLM and encouraged the development of epidemio­

logical studies thoughout the world. Seroprevalence

studies carried out in temperate and tropical countries

have shown that up to 9% of the population have been

infected by

4

In São Paulo, Brazil,

Chieffi et al

6

found 3.6%

antibody positi-

vity in 2025 individuals surveyed6. In addition, high

number of soil and dog fecal samples have been found

contaminated by

eggs in Brazil

4

5 13

However, to the best of our knowledge, only 26 clinical

cases of VLM have been reported in this coun-

try l 3 10 11 14 15 18^ n o n e 0f

them in Bahia State.

In Salvador, contact of children with dogs and

their excreta outside houses seems to be frequent.

Many homeless dogs can be seen in beaches, parks and

streets.

1. Laboratório Central Prof. G onçalo Moniz.

2. Faculdade de M edicina Veterinária.

3. Faculdade de Medicina e Instituto de Ciências da Saúde.

Universidade Federal da Bahia.

Supported by C N Pq project n.° 40.5332/82.

Recebido para publicação em 08/04/87.

The present work aimed at measuring the con­

tamination levels of soil and dog feces collected at

public places by eggs of

in Salvador,

Bahia, as the first step to study possible risk factors for

children to develop visceral larva migrans.

M A T E R IA L A N D M ETH O D S

Two hundred and seventy seven dog fecal

samples and 298 soil samples were collected from the

following sites:

12

parks and public gardens, 18 streets

(both inland and atth e seaside) and 9 beaches, from 23

boroughs of Salvador. Seven to

8

soil samples and all

feces found were taken from each of these sites. The

geographical distribution of the boroughs in seen in

Figure 1.

Soil samples were taken from sites at least one

meter apart from any visible fecal material and

examined within the first 24 hours for the presence of

ascarid eggs by a technique described by Dubin and

colleagues^. Feces were preserved in a merthiolate-

iodo-formalin solution^ and examined by the classical

sedimentation technique.

RESU LTS

From the 298 soil samples and 277 dog fecal

samples examinated, soil was significatly (p <

0

.

0 1

)

more positive (24.8% ) than feces (18.4% ) for eggs of

(Table 1).

The percentages of samples with

eggs

are seen in Figure 1. Eggs in the soil or feces were

found in all boroughs, although in two of them no

T o x o c a r a

were detected on soil and or on dog feces

laid on the ground (Figure 1).

Other parasites found in the soil included:

(26.8% ),

(27.5% ), hookworm (0.6% ) eggs and cysts of

-p o r a s -p

(

2

.

8

%).

A l c â n t a r a N , B a v i a E , S i l v ã o R M , C a r v a l h o E . E n v i r o n m e n t a l c o n t a m i n a t i o n b y T oxocara sp e g g s i n p u b l i c a r e a s o f

S a l v a d o r , B a h i a S t a t e , B r a z i l . R e v i s t a . d a S o c i e d a d e B r a s i l e i r a d e M e d i c i n a T r o p i c a l 2 2 : 1 8 7 - 1 9 0 , O u t - D e z , 1 9 8 9 .

The data were also analysed in terms of sites of

samples collection (Table 2). Soil from parks and

public gardens were more contaminated than beaches

and

streets. These differences were statistically signi­

ficant for all parasites

and other para­

sites, p < 0.01;

p. < 0.05). However,

dog feces contaminated with

eggs were more

prevalente in streets than in other sites (p < 0.01).

D ISC U SSIO N

The most important finding in this work was the

observation of high degree of soil contamination by

eggs of

The degree of contamination, as

expected, was higher than that described by Dubin and

collalaborators in New York, who found a 10% rate of

soil samples contaminated by animal ascarid eggs^. It

was also higher than the data reported in Brazil by

Chieffi & Muller4 and Ferreira et al.12, who found

60% and 41.6% of parks contaminated by

eggs, since we found

eggs in all boroughs

studied. These diferences could be explained by the

relatively large number of samples studied in the

present work or could be in fact a reflection of a higher

prevalence of these parasites in Salvador in relation to

the areas studied by other authors4 12. Although the

number of viable eggs was not determined in the

present study, the possibility that the eggs found in

child’s playing places may be swallowed and cause

VLM should be taken into consideration.

The high degree of positivity for

eggs in the soil as compared to dog feces could be

accounted for by the persistence in the soil of the eggs,

highly resistant to environmental conditions, for se­

veral years after the contaminated feces had been

normally dispersed or washed away. Large egg bur­

dens in a relatively small percentage of contaminated

feces could also contribute to the observed situation.

The high prevalence of

eggs at

the studied areas very likely reflects inadequate sani­

tary conditions. In fact, this prevalence was even

higher than that of

R ESUM O

F o i r e a liz a d o u m in q u é r it o d e o v o s e c is t o s d e

p a r a s i to s e m f e z e s d e c ã e s e s o l o c o le t a d o s e m l o c a i s p ú b lic o s d e 2 3 b a ir r o s d e S a lv a d o r , u m a c id a d e d o N o r d e s t e d o B r a s il, o b j e t iv a n d o d e te r m in a r o s n í v e is d e c o n t a m in a ç ã o d e s s e s l o c a i s p o r o v o s d e T o x o c a r a s p . T o d o s o s b a ir r o s ti v e r a m n í v e is a lt o s d e c o n t a m i n a ç ã o p o r o v o s d e T o x o c a r a s p . O u t r o s p a r a s i t o s e n c o n tr a d o s for am : A s c a r i s l u m b r i c o i d e s , a n c i lo s t o m íd e o s , T r i c h o c e p h a l u s s p e c is t o s d e p r o to z o á r i o s .

A l c â n t a r a N , B a v i a E , S i l v ã o R M , C a r v a l h o E . E n v i r o n m e n t a l c o n t a m i n a t i o n b y T oxocara sp e g g s i n p u b l i c a r e a s o f S a l v a d o r , B a h i a S t a t e , B r a z i l . R e v i s t a d a S o c i e d a d e B r a s i l e i r a d e M e d i c i n a T r o p i c a l 2 2 : 1 8 7 - 1 9 0 , O u t - D e z , 1 9 8 9 .

P a r q u e s e j a r d in s p ú b l i c o s tiv e r a m t a x a s d e c o n t a m in a ç ã o m a is e le v a d a s p a r a t o d o s o s p a r a s it o s , q u a n d o c o m p a r a d o s c o m r u a s e p r a ia s .

Palavras-chaves:

b r i c o i d e s .

Contaminação de solo. Fezes de cães.

R E FE R E N C E S

1. A b e J a c o b C M , Z u c c o lo t t o S M C , P e r e s B A , B a c h -R iz e t ti B C , O s e lk a G W , C a m a r g o M E , C h e n S . L a r v a m ig r a n s v i s c e r a l p o r T o x o c a r a c a n i s . E s t u d o d a s c a r a c ­ t e r ís t ic a s c lí n i c a s e la b o r a to r ia i s d e 7 c a s o s h u m a n o s . R e v i s t a d a A s s o c i a ç ã o M é d ic a B r a s ile ir a 3 0 : 1 8 7 - 9 1 , 1 9 8 4 .

2 . B e a v e r P C . T h ? n a tu r e o f v i s c e r a l la r v a m ig r a n s . T h e J o u r n a l o f P a r a s it o l o g y 5 5 : 3 - 1 2 , 1 9 6 9 .

3 . C h ia t t o n e C S , C h ie f f i P P , P a e s R A P . S ín d r o m e d e la r v a m ig r a n s v is c e r a l e m a d u lto . A p r e s e n t a ç ã o d e u m c a s o . R e v i s t a d o I n s t it u t o A d o l f o L u t z 4 3 : 8 5 - 8 8 , 1 9 8 3 .

4 . C h ie f f i P P , M ü lle r E E . P r e v a lê n c i a d e p a r a s i t is m o p o r

T o x o c a r a c a n i s e m c ã e s e p r e s e n ç a d e o v o s d e T o x o c a r a s p n o s o l o d e l o c a lid a d e s p ú b lic a s d a z o n a u r b a n a d o m u n ic íp io d e L o n d r in a , E s t a d o d o P a r a n á , B r a s il. R e v i s ­ t a d e S a ú d e P ú b lic a 1 0 : 3 6 7 - 3 7 2 , 1 9 7 6 .

5 . C h ie ff i P P , M ü lle r E E . E s t u d o d a v a r ia ç ã o m e n s a l n a c o n t a m in a ç ã o d o s o l o p o r o v o s d e T o x o c a r a s p ( N e m a -to d a , A s c a r o i d e a ) , n a z o n a u r b a n a d o m u n ic íp io d e L o n d r in a , E s t a d o d o P a r a n á , B r a s il. R e v i s t a d o I n s t it u t o A d o lf o L u t z 3 8 : 1 3 - 1 6 , 1 9 7 8 .

6 . C h ie f fi P P , V e d a M , C a m a r g o E D , S o u z a A M C . S ín ­ d r o m e d e la r v a m ig r a n s v is c e r a l: P e s q u i s a d e a n t ic o r p o s anti- T o x o c a r a e m p a c i e n t e s c o m h ip e r e o s in o f il ia . R e v i s ­ t a d a S o c i e d a d e B r a s i le ir a d e M e d ic i n a T r o p ic a l 2 0 (su p l): 8 5 , 1 9 8 7 .

7 . D e S a v i g n y D H . I n v i t r o m a in t e n a n c e o f T o x o c a r a c a n i s la r v a e a n d a s im p le m e t h o d fo r th e p r o d u c t io n o f T o x o ­ c a r a E S a n tig e n f o r u s e in s e r o d ia g n o s t ic t e s t s fo r v is c e r a l la rv a m ig r a n s . T h e J o u r n a l o f P a r a s it o l o g y 6 1 : 7 8 1 - 7 8 2 , 1 9 7 5 .

8 . D e S a v i g n y D H , V o l l e r A , W o o d r u f f A W . T o x o c a r ia s is : s e r o lo g ic a l d ia g n o s t ic b y e n z y m e im m u n o a s s a y . J o u r n a l o f C l i n i c a l P a t h o l o g y 3 2 : 2 8 8 , 1 9 7 9 .

9 . D u b in S , S e g a l l S , M a r t in d a le J . C o n t a m in a t io n o f s o i l in t w o c i t y p a r k s w it h c a n in e n e m a t o d e o v a in c lu d in g T o x o c a r a c a n i s : p r e lim in a r y s tu d y . A m e r i c a n J o u r n a l o f P u b lic H e a l t h 1 2 4 2 - 1 2 4 5 , 1 9 7 2 .

1 0 . F a r ia R , R s t o m F M . L a r v a M ig r a n s V is c e r a l is ( S i n -d r o m e -d e L o e f f le r p o r T o x o c a r a c a n i s ) . P e d ia t r ia M o ­ d e r n a 1 6 : 1 9 0 - 1 9 6 , 1 9 8 1 .

1 1 . F e r r a z C N , K e r b a u y J , F a r h a t C K , C la r o J T , S i l v a M P . E o s i n o f i l ia r e la c io n a d a à “ la r v a m ig r a n s ” v i s c e r a l. R e ­ v i s t a d a A s s o c i a ç ã o M é d i c a B r a s i le ir a 2 6 : 2 5 3 - 2 5 4 ,

1 9 8 0 .

1 2 . F e r r e ir a L F , O li v e ir a E L , C a m illo - C o u r a L . S o b r e a p r e s e n ç a d e o v o s d e T o x o c a r a e m p r a ç a s d a c id a d e d o R io d e J a n e ir o . R e v i s t a d a S o c i e d a d e B r a s i le ir a d e M e d ic in a T r o p ic a l 1 0 : 5 1 - 5 4 , 1 9 7 6 .

1 3 . J o s e p h s o n S L . H u m a n t o x o c a r i a s i s . C lin ic a l M ic r o b i o ­ l o g y N e w s L e t t e r 1 0 : 2 5 - 2 5 , 1 9 8 8 .

1 4 . K ö b e r le F , A r t ig a s P T . C o n s i d e r a ç õ e s e m t o m o d e d o i s c a s o s d e “ la r v a m ig r a n s ” v is c e r a l. In: R e s u m o s d o V I C o n g r e s s o B r a s i le ir o d e P a r a s it o lo g ia . B e l o H o r i z o n t e P .

1 2 8 , 1 9 8 1 .

1 5 . S a lz m a n M . R e l a t o d e C a s o d e T o x o c a r í a s e . J o r n a l d e P e d ia t r ia 5 9 : 2 0 5 - 2 0 6 , 1 9 8 5 .

A l c â n t a r a N , B a v i a E , S i l v ã o R M , C a r v a lh o E . E n v i r o n m e n t a l c o n t a m i n a t i o n b y

Toxocara sp

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