[Studies on human streptococcal infectious syndrome caused by infected pigs].
OBJECTIVE
To demonstrate the clinical manifestations of S. suis infectious syndrome; to study the characteristics of causative organism and its source.


METHODS
25 cases of unknown causes of food poisoning were identified in the central area of Jiangsu province, China in July 1998. Biological specimens was collected in some patients, and the causative organism was isolated using a number of different culture medium. Isolated organisms were identified by serum antibody tests, API biochemical tests, drug sensitivity tests and animal model experiments. The human born strains and the pig born strains were compared by RAPD technique. Epidemiological methods were applied to trace the source of causative organisms.


RESULTS
Cases were clinically categorized into two types: Streptococcal toxic shock syndrome (STSS) and streptococcal meningitis syndrome (SMS). Three strains of streptococci were isolated respectively from the blood and cerebrospinal fluid of 6 cases. All these 6 strains were confirmed to be S. suis type 2 by culture characteristics, morphology, biochemical characteristics, serum antibody tests and fatty acid profile analysis. Animal model experiment showed that these strains were sensitive to rabbits and pigs, but not to rats. RAPD fingerprint test revealed an identity between human born and pig born strains.


CONCLUSIONS
The aetiological agent of these human cases was S. suis type 2. Human cases were contracted by direct contact with the infected pigs or the corpse of infected pigs.
Hu
X
X
Jiangsu Provincial Sanitary and Health Center, Nanjing 210009, China.
Zhu
F
F
Wang
H
H
Chen
S
S
Wang
G
G
Sun
J
J
Hua
C
C
Yang
H
H
D000328:Adult; D000368:Aged; D000818:Animals; D005260:Female; D006801:Humans; D008297:Male; D016920:Meningitis, Bacterial / Q000382:microbiology / Q000635:transmission; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011817:Rabbits; D051381:Rats; D012772:Shock, Septic / Q000209:etiology* / Q000382:microbiology / Q000635:transmission; D013290:Streptococcal Infections / Q000382:microbiology / Q000635:transmission* / Q000662:veterinary; D017011:Streptococcus suis / Q000145:classification / Q000302:isolation & purification*; D013552:Swine; D013553:Swine Diseases / Q000635:transmission*; D013577:Syndrome