In 1990 Congo-Crimean Hemorrhagic Fever was first recognized in Saudi Arabia as an outbreak in Makkah slaughterhouse workers and in the community. Epidemiologic studies suggested that humans became infected through percutaneous exposure while slaughtering or butchering livestock. In 1991 we extended our studies to Jeddah slaughterhouses to support our previous finding and to demonstrate infection there.
Methodology
We interviewed 112 workers from both Jeddah slaughterhouses about work history, work practices and recent illness. We obtained serum specimens from each worker.
Results
Ten percent of workers had antibody to CCHF. Seropositivity among freelance slaughtermen was 33%, compared with 7% in contracted workers (p<0.02, Fisher's exact test). Of five workers reporting hospitalization with a febrile illness in the preceding year, three (60%) had high (IFA ≥ 1:64) CCHF antibody titer (p<0.01, Fisher's exact test). Seropositive workers reported a median of 6.1 cuts per year, compared with 0.7 cuts per year for seronegative (p<0.02, Krusal-Wallis test).
Conclusion
Percutaneous exposure to animal blood or tissues has probably led to most CCHF infection in these workers. Severe symptomatic infections probably occurred and were more common than mild or asymptomatic infections. These data support previous findings in Makkah and show a more widespread distribution of CCHF.