[Typhoid fever in north Lebanon: a 8-year study (1992-1999) using the Widal test].

We evaluated the frequency of typhoid fever in north Lebanon over an 8-year period (1992-1999) in patients admitted with fever to the Islami de Bienfaisance Hospital in Tripoli. We analysed 7391 serum samples for Salmonella typhi infection using the Widal and Felix tests. The cut-off value for infection was an agglutinin O titre > or = 1/160 (a value validated in an earlier study in the same region). Of the 7391 samples, 1131 (15.3%) had an agglutinin O titre > or = 1/160. The 8-year surveillance showed there was a progressive decrease in the frequency of the disease. However with over 100 cases annually, typhoid is endemic in the area and could cause major outbreaks. The monthly analysis shows that we have an increase in summer, whilst a decrease is observed in winter.