BACKGROUND: The California Department of Public Health (CDPH) Sentinel Provider Influenza Surveillance Program collects weekly patient visit data from volunteer healthcare providers, or sentinel providers (SPs), who report patients with influenza-like illness (ILI) and submit specimens on a subset of ILI patients during the influenza season. As an incentive for participation in California, continuing SPs who report ILI patients >50% of the early weeks of the influenza season and newly enrolled SPs are eligible to receive influenza rapid test kits (RTKs). Our objective was to describe SP reporting and specimen submission among providers receiving RTKs.
METHODS: California SPs enrolled during the 2014-2015 influenza season who were assigned to submit specimens to the CDPH Viral and Rickettsial Diseases Laboratory (VRDL) were included. SPs assigned to submit specimens to their local health jurisdiction laboratories and SPs associated with local syndromic surveillance systems were excluded. SPs specimen submission information was obtained from VRDL and SP ILI reporting records were obtained from the Centers for Disease Control and Prevention.
RESULTS: Two-hundred SPs met inclusion criteria during the 2014-2015 season; 176 (88%) continuing SPs and 24 (12%) new SPs. Of the 176 continuing SPs, 94 (53%) reported regularly, i.e., ≥50% of the peak weeks during influenza season, of whom 93 also met RTK eligibility requirements at the beginning of the season. Of the 93 SPs eligible to receive RTKs, 13 of 67 (19%) who did not request RTKs and 11 of 26 (42%) who did request RTKs submitted specimens (p=.02). Of the 24 new SPs, 21 (88%) reported at least once, 16 (67%) reported regularly during the season, and 6 (25%) submitted specimens.
CONCLUSIONS: While regularly reporting continuing SPs who received RTKs were more likely to submit specimens than those who did not, less than half of those who received RTKs submitted specimens for influenza testing. Including specimen submission as part of the RTK eligibility requirements could improve SP specimen submission, which provides important information about circulating influenza strains. Unlike continuing SPs, newly enrolled SPs are not required to report ILI activity to receive RTKs, and as a result, resources are lost when new SPs do not regularly report or submit specimens. Eliminating RTKs provided at enrollment would allow additional RTKs to be provided to regularly reporting SPs, including new providers, during the peak weeks of influenza season when RTKs have greater positive predictive value.