Surveillance for tuberculosis in Alaska, 1986

Area of Science:

• Public Health
• Epidemiology
• Infectious Diseases

Background:

• Tuberculosis (TB) incidence in Alaska Native populations (92.2/100,000) significantly exceeds the U.S. national rate (9.3/100,000).
• Effective tuberculosis surveillance is crucial for controlling disease spread in high-risk populations.

Purpose of the Study:

• To describe the tuberculosis surveillance system in Alaska.
• To estimate the positive predictive value of TB cases reported in 1986.
• To identify areas for improvement in TB surveillance strategies.

Main Methods:

• Active surveillance included itinerant chest clinics, survey chest radiography, and contact investigations.
• Passive surveillance relied on reports from healthcare providers and the U.S. Immigration and Naturalization Service.
• Analysis focused on cases recorded by the surveillance system in 1986.

Main Results:

• Healthcare providers reported half of all new tuberculosis cases.
• Only 42% of reported cases were bacteriologically confirmed, lower than the national average (87%), indicating potential false positives.
• Incomplete contact investigations were noted for many cases.

Conclusions:

• The Alaskan tuberculosis surveillance system requires enhancement to improve accuracy and completeness.
• Recommendations include stricter adherence to diagnostic criteria, increased contact investigations, and targeted surveillance for high-risk groups.