Economic analysis of CDC's culture- and smear-based tuberculosis instructions for Filipino immigrants

Abstract

Setting: In 2007, the US Centers for Disease Control and Prevention (CDC) revised its tuberculosis (TB) technical instructions for panel physicians who administer mandatory medical examinations among US-bound immigrants. Many US-bound immigrants come from the Philippines, a high TB prevalence country.

Objective: To quantify economic and health impacts of smear- vs. culture-based TB screening.

Design: Decision tree modeling was used to compare three Filipino screening programs: 1) no screening, 2) smear-based screening, and 3) culture-based screening. The model incorporated pre-departure TB screening results from Filipino panel physicians and CDC databases with post-arrival follow-up outcomes. Costs (2013 $US) were examined from societal, immigrant, US Public Health Department and hospitalization perspectives.

Results: With no screening, an annual cohort of 35 722 Filipino immigrants would include an estimated 450 TB patients with 264 hospitalizations, at a societal cost of US$9.90 million. Culture-based vs. smear-based screening would result in fewer imported cases (80.9 vs. 310.5), hospitalizations (19.7 vs. 68.1), and treatment costs (US$1.57 million vs. US$4.28 million). Societal screening costs, including US follow-up, were greater for culture-based screening (US$5.98 million) than for smear-based screening (US$3.38 million). Culture-based screening requirements increased immigrant costs by 61% (US$1.7 million), but reduced costs for the US Public Health Department (22%, US$750 000) and of hospitalization (70%, US$1 020 000).

Conclusion: Culture-based screening reduced imported TB and US costs among Filipino immigrants.

Figure 1.

One-way sensitivity analysis of total societal costs and total imported cases, as functions of tuberculosis disease prevalence among Filipinos