Targeted Screening for Chronic Q Fever, the Netherlands

Area of Science:

• Infectious Diseases
• Public Health
• Epidemiology

Background:

• Chronic Q fever, caused by Coxiella burnetii, can lead to severe complications if not detected early.
• A large Q fever outbreak in the Netherlands necessitated long-term monitoring and screening strategies.
• General practitioner practices are key sites for identifying and managing chronic infections in the community.

Purpose of the Study:

• To evaluate the effectiveness and cost-effectiveness of a targeted chronic Q fever screening program.
• To assess the prevalence of chronic Q fever in high-risk populations years after a major outbreak.
• To determine if early detection through screening can prevent severe outcomes.

Main Methods:

• A screening program was implemented in 13 general practitioner practices in outbreak areas.
• 3,419 patients with specific underlying medical conditions were identified for potential screening.
• 1,642 patients (48% participation) underwent serum testing using immunofluorescence assay for Coxiella burnetii antibodies.

Main Results:

• 18% (289/1,642) of participants showed evidence of previous Coxiella burnetii infection (IgG II titer >1:64).
• 9 patients were suspected of having chronic Q fever (IgG I y titer >1:512) based on serological results.
• 4 patients were ultimately diagnosed with chronic Q fever after medical evaluation.

Conclusions:

• Targeted screening effectively identified patients with chronic Q fever even years after a large outbreak.
• Despite higher-than-estimated costs, the screening program demonstrated cost-effectiveness in specific high-risk groups.
• Early detection and treatment of chronic Q fever are crucial for preventing potentially life-threatening complications.