Long-term follow-up of schistosomiasis serology post-treatment in Australian travelers and immigrants.
BACKGROUND
We undertook an observational follow-up study of schistosomiasis serology in both travelers and immigrants in a nonendemic country to determine the natural history of schistosomiasis antibody titer post-adequate treatment in those who have not been reexposed.


METHODS
Longitudinal study of all adult travelers and immigrants presenting to the Royal Melbourne Hospital, Australia with positive schistosomiasis serology (titer >1: 64) between July 1995 and December 2005. All patients were treated with praziquantel and followed up clinically and serologically for a period up to 30 months.


RESULTS
A total of 58 patients were included in the study including 26 travelers and 32 immigrants. Antibody titers often increased in the first 6 to 12 months post-treatment, especially in immigrants. After 30 months of post-treatment, 68% of travelers and 35% of immigrants (p < 0.01) achieved a fourfold antibody decline.


CONCLUSIONS
Schistosomiasis antibody titers varied after adequate treatment. Therefore an increase in titer in the first 6 to 12 months or a failure to reduce after 3 years should not automatically justify re-treatment.
Yong
Michelle K
MK
Victorian Infectious Diseases Service, Royal Melbourne Hospital, Parkville, Victoria, Australia. michyong@yahoo.com
Beckett
Carolyn L
CL
Leder
Karin
K
Biggs
Beverley A
BA
Torresi
Joseph
J
O'Brien
Daniel P
DP
D000328:Adult; D000871:Anthelmintics / Q000627:therapeutic use; D001315:Australia / Q000453:epidemiology; D004641:Emigration and Immigration; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D011223:Praziquantel / Q000627:therapeutic use; D012552:Schistosomiasis / Q000097:blood / Q000188:drug therapy / Q000453:epidemiology*; D018709:Statistics, Nonparametric; D014195:Travel; D016896:Treatment Outcome
D000871:Anthelmintics; D011223:Praziquantel