Query purpose:
To assist state, local, tribal, territorial, and federal public health practitioners in identifying patients likely to have long COVID (also commonly described as Post-COVID Complications (PCC) or long-haul COVID) by reviewing visits in the emergency department (ED) setting and to help with trend monitoring for long COVID related visits using syndromic surveillance data.
How it was developed:
Subject matter experts from seven jurisdictions (WA; VA; Harris County, TX; Pierce-Tacoma County, WA; NE; KS; KY) created and validated the definition using ED visit data from January – December 2023.
- Literature review on long COVID to identify common symptoms and complaints and alternative syndrome names.
- Search for diagnosis codes (International Classification of Diseases, 10th Revision (ICD10-CM) and Systematized Nomenclature of Medicine (SNOMED)) relevant to long COVID.
- Query relevant diagnosis codes under Discharge Diagnosis Parsed and relevant free text terms under Chief Complaint History in ESSENCE and run text analysis to identify: 1. Any missing, relevant diagnosis codes and/or free text terms to include, 2. Any irrelevant diagnosis codes and free text terms to exclude.
- Update definition to include free text and diagnosis code inclusion and exclusion terms.
- Validate definition using validation steps outlined below.
How it works:
The Discharge Diagnosis Parsed Free Text field and Chief Complaint History field (also applied to Triage Notes Orig and Admit Reason Combo) are used to query discharge diagnosis codes and free text, respectively, with exclusions (as necessary), to develop the syndrome definition. This definition requires BOTH discharge diagnosis AND free-text indication of suspected long COVID.
- Inclusions based on long COVID related discharge diagnosis codes:
- The visit is included if in addition to one of the free text inclusion terms below, it also contains:
- A discharge diagnosis code of Post-COVID conditions (U099 or 1119304009), History of COVID-19 (Z8616), or Post-Viral Fatigue Syndrome (G933)
- The visit is included if in addition to one of the free text inclusion terms below, it also contains:
- Inclusions based on free text terms:
- The visit is included if in addition to one of the discharge diagnosis codes above, it also contains:
- “had covid”, “long term covid”, “post acute covid”, “post acute sequela” and “covid”, “long haul covid”, “long covid”, “post covid”, “after covid”, “pots” and “covid”, “viral fatigue syndrome” and “covid”
- The above must exclude:
- Concurrent free text terms:
- “had covid test”, “positive for covid on [MTWFS0-9]”, “covid positive on [MTWFS0-9]”, “covid positive mond”, “covid positive tue”, “covid positive wed”, “covid positive th”, “covid positive fri”, “covid positive sat”, “covid positive sun”, “covid positive today”, “covid positive yesterday”, “covid positive [0-9][0-9]/”, “covid positive [0-9]/”, “positive for covid mond”, “positive for covid tue”, “positive for covid wed”, “positive for covid th”, “positive for covid fri”, “positive for covid sat”, “positive for covid sun”, “covid today”, “covid yesterday”, “covid this”, “positive for covid [0-9][0-9]/”, “positive for covid [0-9]/”, “resolved post_covid”, “post covid result”, “covid” and “shot” or “vacc” or “vax” or “vaccine” or “booster” or “immunization” or “injection” or “exposure” or “reaction”, “requested covid test”, “covid [123] w”, “covid [123]w”, “covid x[123][wd]”, “covid x [123][wd]”, “covid x[123] [wd]”, “covid x [123] [wd]”, “covid positive [123] [wd]”, “covid positive [123][wd]”, “covid positive x[123][wd]”, “covid positive x [123][wd]”, “covid positive x[123] [wd]”, “covid positive x [123] [wd]”, “covid [12].5 w”, “covid [12].5w”, “covid x[12].5w”, “covid x [12].5w”, “covid x[12].5 w”, “covid x [12].5 w”, “covid positive [12].5 w”, “covid positive [12].5w”, “covid positive x[12].5w”, “covid positive x [12].5w”, “covid positive x[12].5 w”, “covid positive x [12].5 w”, “covid three [wd]”, “covid two [wd]”, “covid one [wd]”, “covid a [wd]”, “covid positive three [wd]”, “covid positive two [wd]”, “covid positive one [wd]”, “covid positive a [wd]”, “days post_covid”, “[23] weeks post_covid”, “[23] wks post_covid”, “wk post_covid”, “week post_covid”, “twoish weeks post_covid”, “two weeks post_covid”, “two wks post_covid”, “three weeks post_covid”, “three wks post_covid”, “recently covid”, “recent covid”, “hx pots”, “covid [123] ago”, “covid three ago”, “covid two ago”, “covid one ago”, “covid positive [123] ago”, “covid positive three ago”, “covid positive two ago”, “covid positive one ago”, “covid [1-9] day”, “covid [12][0-9] day”, “covid x[1-9] day”, “covid x[12][0-9] day”, “covid x [1-9] day”, “covid x [12][0-9] day”, “covid positive [1-9] day”, “covid positive [12][0-9] day”, “was positive last w”, “covid last [TWFS]”, “covid last mond”, “covid positive last [TWFS]”, “covid positive last mond”, “[23] wks after covid”, “[23] weeks after covid”, “wk after covid”, “week after covid”, “two weeks after covid”, “two wks after covid”, “three weeks after covid”, “three wks after covid”, “after covid check_up”, “medical clearance”
- Concurrent free text terms:
- The visit is included if in addition to one of the discharge diagnosis codes above, it also contains:
For consideration:
Most false positives are visits that have current COVID-19 infection or infection less than one month ago. These visits are difficult to exclude due to inconsistencies in the use of the U09.9 code. Sometimes, providers code the U09.9 code less than one month following COVID-19 infection as indicated via free-text. These visits will need to be excluded via manual review. Further, acute COVID free-text exclusion criteria could cause false negatives for health encounters for long COVID symptom exacerbation due to recent reinfection.
Discharge Diagnosis Parsed Free Text:
^;U099^,or,^;Z8616^,or,^;G933^,or,^;1119304009;^
AND
Chief complaint history also apply to Triage Notes Orig, Admit Reason Combo:
(,^had covid^,or,^long_term covid^,or,^post_acute covid^,or,(,^post_acute sequela^,and,^covid^,),or,^long_haul covid^,or,^long_covid^,or,^post_covid^,or,^after covid^,or,(,(,!pots!,or,^[;., ]pots[ ;.,]^,),and,^covid^,),or,(,^viral fatigue syndrome^,and,^covid^,),),ANDNOT,(,^had covid test^,or,^positive for covid on [MTWFS0-9]^,or,^covid positive on [MTWFS0-9]^,or,^covid positive mond^,or,^covid positive tue^,or,^covid positive wed^,or,^covid positive th^,or,^covid positive fri^,or,^covid positive sat^,or,^covid positive sun^,or,^covid positive today^,or,^covid positive yesterday^,or,^covid positive [0-9][0-9]/^,or,^covid positive [0-9]/^,or,^positive for covid mond^,or,^positive for covid tue^,or,^positive for covid wed^,or,^positive for covid th^,or,^positive for covid fri^,or,^positive for covid sat^,or,^positive for covid sun^,or,^covid today^,or,^covid yesterday^,or,^covid this^,or,^covid [0-9][0-9]/^,or,^covid [0-9]/^,or,^resolved post_covid^,or,^post covid result^,or,(,^covid^,and,(,^shot^,or,^vacc^,or,^vax^,or,^booster^,or,^immunization^,or,^injection^,or,^exposure^,or,^reaction^,),),or,^requested covid test^,or,^covid [123] w^,or,^covid [123]w^,or,^covid x[123][wd]^,or,^covid x [123][wd]^,or,^covid x[123] [wd]^,or,^covid x [123] [wd]^,or,^covid positive [123] [wd]^,or,^covid positive [123][wd]^,or,^covid positive x[123][wd]^,or,^covid positive x [123][wd]^,or,^covid positive x[123] [wd]^,or,^covid positive x [123] [wd]^,or,^covid [12].5 w^,or,^covid [12].5w^,or,^covid x[12].5w^,or,^covid x [12].5w^,or,^covid x[12].5 w^,or,^covid x [12].5 w^,or,^covid positive [12].5 w^,or,^covid positive [12].5w^,or,^covid positive x[12].5w^,or,^covid positive x [12].5w^,or,^covid positive x[12].5 w^,or,^covid positive x [12].5 w^,or,^covid three [wd]^,or,^covid two [wd]^,or,^covid one [wd]^,or,^covid a [wd]^,or,^covid positive three [wd]^,or,^covid positive two [wd]^,or,^covid positive one [wd]^,or,^covid positive a [wd]^,or,^days post_covid^,or,^[23] weeks post_covid^,or,^[23] wks post_covid^,or,^wk post_covid^,or,^week post_covid^,or,^twoish weeks post_covid^,or,^two weeks post_covid^,or,^two wks post_covid^,or,^three weeks post_covid^,or,^three wks post_covid^,or,^recently covid^,or,^recent covid^,or,^hx pots^,or,^covid [123] ago^,or,^covid three ago^,or,^covid two ago^,or,^covid one ago^,or,^covid positive [123] ago^,or,^covid positive three ago^,or,^covid positive two ago^,or,^covid positive one ago^,or,^covid [1-9] day^,or,^covid [12][0-9] day^,or,^covid x[1-9] day^,or,^covid x[12][0-9] day^,or,^covid x [1-9] day^,or,^covid x [12][0-9] day^,or,^covid positive [1-9] day^,or,^covid positive [12][0-9] day^,or,^was positive last w^,or,^covid last [TWFS]^,or,^covid last mond^,or,^covid positive last [TWFS]^,or,^covid positive last mond^,or,^[23] wks after covid^,or,^[23] weeks after covid^,or,^wk after covid^,or,^week after covid^,or,^two weeks after covid^,or,^two wks after covid^,or,^three weeks after covid^,or,^three wks after covid^,or,^after covid check_up^,or,^medical clearance^,)