Background:
As a component of a comprehensive syphilis control program, positive syphilis test results from laboratories are reported to the health department and entered into a reactor database. The CDC recommends periodic analysis of the reactor database for readjustment of follow-up priorities. Follow-up of all priority reactors is a resource-intensive activity if conducted by DIS and alternate strategies may be necessary to maximize health department resources.

Objective:
To analyze yield reactors initiated for DIS follow-up and in order to refine the current reactor grid.

Method:
From 2003 through 2004, a sensitivity and specificity analysis of reactor criteria was performed on all reactors initiated in six local health jurisdictions with the highest morbidity for syphilis within the California Project Area.

Result:
In this period, staff initiated 3567 reactors for follow-up. Of these, 923 (25.9%) were infectious early syphilis cases. Following CDC reactor priority 1's and 2's resulted in a sensitivity of 94.6% for males and 98.2% for females and a specificity of 24.0% for males and 10.7% for females. Of the 300 pregnant female reactors, 38% were newly diagnosed latent infections (of unknown duration or >1yr) and only 5% were newly diagnosed early syphilis cases. By provider type, 47% of initiated reactors from HIV/EIP providers were new early syphilis infections, 31% from STD clinics, 30% from public clinics, and 26% from private providers.

Conclusion:
Given California's current epidemiologic profile, CDC's recommended priority follow-up for syphilis, in females, is of low yield. Priorities for reactor follow-up should be localized and provider type should be considered as a grid variable.


Implications:
Refinement of the reactor grid results in more cost effective utilization of DIS staff and streamlines follow-up to identify infectious syphilis, thus focusing resources on disease intervention and other areas of greater public health impact, as opposed to medical management.