Skip main navigation

Military Health System

Clear Your Browser Cache

This website has recently undergone changes. Users finding unexpected concerns may care to clear their browser's cache to ensure a seamless experience.

Brief report: Using syndromic surveillance to monitor MIS-C associated with COVID-19 in Military Health System beneficiaries

Image of Cover 4. Air Force 1st Lt. Anthony Albina, a critical care nurse assigned to Joint Base Andrews, Md., checks a patient’s breathing and heart rate during an intubation procedure while supporting COVID-19 response operations in Cleveland, Jan. 20, 2022.

Background

SARS CoV-2 and the illness it causes, COVID-19, have exacted a heavy toll on the global community. Most of the identified disease has been in the elderly and adults. In April 2020, a rare hyperinflammatory syndrome called multisystem inflammatory syndrome in children (MIS-C) was reported in Europe in a number of children with SARS-CoV2 infections. The cluster was initially characterized as cases with symptoms compatible with Kawasaki's disease.1 Cases presented with symptoms including systemic hyperinflammation, persistent fever, and multisystem organ dysfunction. In the U.S., cases of MIS-C have been disproportionately reported among Hispanic and non-Hispanic Black children 6 to 12 years old who presented with severe symptoms.2 According to the Centers for Disease Prevention and Control (CDC), as of 3 May 2021, 3,742 cases of MIS-C were reported in the U.S., including 35 deaths.3

In an effort to detect potential cases of MIS-C in the Military Health System (MHS), the Armed Forces Health Surveillance Division (AFHSD) used the Electronic Surveillance System for the Early Notification of Community-based Epidemics (ESSENCE), a syndromic surveillance system which uses outpatient data to monitor trends and increases in health care encounters that may represent changes in the incidence of disease. Users of ESSENCE employ the system to analyze MHS clinical data sources in near real-time, including diagnosis codes, free text chief complaint or reason-for-visit data fields, reportable medical events (RME), laboratory and radiology data, and prescription drug information to develop a picture of disease syndromes based on health care encounters.4,5 The goal of this analysis was to ascertain if user-built ESSENCE queries applied to records of outpatient MHS health care encounters are capable of detecting MIS-C cases that have not been identified or reported by local public health departments.

Methods

The AFHSD used ESSENCE to create a query based on the case definition of MIS-C developed by the CDC to identify potential MIS-C cases. The query included MIS-C-related International Classification of Diseases, 10th Revision (ICD-10) diagnosis codes and free text chief complaint and reason-for-visit data fields from records of outpatient medical encounters for health care beneficiaries of the MHS 20 years old or younger who sought care between Oct. 19, 2020 and March 12, 2021. The query was adapted from the CDC-developed syndromic surveillance query, but the AFHSD query was modified to exclude those codes which are not present in AFHSD ESSENCE (Z86.16 [personal history of COVID-19] and Z20.822 [exposure to COVID-19 or SARS-CoV-2 infection]). The AFHSD-developed query selected ICD-10 codes in any diagnostic position in the electronic medical record for any outpatient encounter during the study period. Chief complaints were retrieved from patients' "reason for visit" free text field for each health encounter. The search criteria for ESSENCE's free text queries are built around Boolean logical operators and regular expressions which allow for a high level of customization.6

Four ICD-10 codes and 12 chief complaints (Tables 1, 2) were used to create the automated ESSENCE MIS-C query for searching records of all outpatient health encounters at nearly 400 military treatment facilities (MTFs) in real-time. Demographic and military variables, including age (in years), sex, race/ethnicity, ICD-10 codes, patient identifiers, and location were extracted for analysis. All Click to closeDirect CareDirect care refers to military hospitals and clinics, also known as “military treatment facilities” and “MTFs.”direct care outpatient encounters with 1 or more of the ICD-10 codes or chief complaints of interest were selected to create a list of potential cases. Data details were downloaded on a weekly basis, verified, and coded as confirmed MIS-C cases by registrars trained in infectious disease manual data abstraction associated with the Department of Defense (DoD) COVID-19 registry.

The CDC case definition was used to confirm MIS-C cases. This definition includes an individual under 21 years old presenting with fever (>100.4 °F/38.0 °C) or report of subjective fever lasting 24 hours or longer), laboratory evidence of inflammation and a positive test for SARS-CoV-2 infection by RT-PCR, serology, or antigen test or COVID-19 exposure within the 4 weeks prior to the onset of symptoms in the clinical setting of severe inflammatory illness without other identifiable etiology.3

Results

During the surveillance period, the AFHSD MIS-C ESSENCE query identified 60 encounters that met selection criteria. The month of February 2021 had the most MIS-C-related encounters with 15 (25%) occurring during this time (data not shown). Out of 60 possible cases, 40 (66%) were males and 36 (60%) were 0–8 years olds (mean=8.5 years) (data not shown). Half of the MIS-C-related encounters (n=30) were in the southeast region of the U.S., and 9 (15%) were in overseas military clinics (data not shown). The most common ICD-10 code recorded was "M30.3-Mucocutaneous lymph node syndrome (Kawasaki)." Of the 60 records identified as possible cases by ESSENCE, 10 cases of MIS-C were confirmed by the DoD COVID-19 health records review process (17%). Four (40%) of the 10 confirmed cases were male and 4 were female (40%). Information on sex was not available for 2 of the confirmed cases. Half of the confirmed cases were 7–10 years old (mean=12 years; range=7–18 years).

Editorial Comment

Monitoring disease progression of the COVID-19 pandemic for situational awareness has been the current focus of the syndromic surveillance. The emergence of MIS-C reported in military beneficiaries should widen the focus on how to monitor disease progression in diverse populations. Although MIS-C is a rare condition among children who have developed COVID-19, it is still of great concern to public health officials in the military health care system.4 The ability to detect individual cases of disease was not originally how syndromic surveillance was designed to function. The main objective of syndromic surveillance is to detect a cluster or outbreak of disease before diagnosis.

There are some limitations to using ESSENCE to detect MIS-C encounters. A proportion of ESSENCE records that were received were deidentified; these records were not used in the analysis. In addition, records of Click to closePurchased CareThe TRICARE Health Program is often referred to as purchased care. It is the services we “purchase” through the managed care support contracts.purchased care encounters were not included in the analysis. Given these limitations, the findings of this analysis should not be construed as a complete representation of MIS-C cases in the surveyed population. Moreover, because the use of ESSENCE was limited to outpatient clinic data, the current analysis did not include the more severe cases seen in emergency departments and urgent care centers which are visible through the civilian form of ESSENCE.

The purpose of the analysis was to create a query that could identify possible outpatient cases of MIS-C. The MIS-C query was able to capture 10 cases of the rare condition of MIS-C during the surveillance period while minimizing the number of encounters (n=60) which met the selection criteria out of millions of encounters. ESSENCE has shown the ability to detect potential cases of MIS-C through health encounters at MTFs across the MHS. This capability will expand the biosurveillance efforts of AFHSD in response to future emerging infectious diseases and other threats of military interest. Furthermore, civilian surveillance systems may use this or similar queries to identify previously unreported cases of MIS-C in the civilian population.

Author affiliations: Armed Forces Health Surveillance Division, Silver Spring, MD (Dr. Russell and Col. Vick).

References

1. Riphagen S, Gomez X, Gonzalez-Martinez C, et al. Hyperinflammatory shock in children during COVID-19 Pandemic. Lancet. 2020;395(10237):1607–1608.

2. Feldstein LR, Tenforde MW, Friedman KG, et al. Characteristics and outcomes of US children and adolescents with multisystem inflammatory syndrome in children (MIS-C) compared with severe acute COVID-19. JAMA. 2021;325(11):1074–1087. 

3. Centers for Disease Control and Prevention. Health Department-Reported Cases of Multisystem Inflammatory Syndrome in Children (MIS-C) in the United States. Centers for Disease Control and Prevention. 11 May 2021. Accessed 1 June 2021. https://covid.cdc.gov/covid-data-tracker/#mis-national-surveillance

4. Burkom H, Loschen W, Wojcik R, et al. Electronic Surveillance System for the Early Notification of Community-Based Epidemics (ESSENCE): Overview, Components, and Public Health Applications. JMIR Public Health Surveill. 2021;7(6):e26303.

5. Scholl L, Liu S, Vivolo-Kantor A, et al. Development and Validation of a Syndrome Definition to Identify Suspected Nonfatal Heroin-Involved Overdoses Treated in Emergency Departments. J Public Health Manag Pract. 2021;27(4):369–378. 

6. Stein Z. National Syndromic Surveillance Program (NSSP). Free-text coding in NSSP-ESSENCE: Part 1. Accessed 1 December 2021. https://www.cdc.gov/nssp/tech-tips/free-text-coding/part1.html

7. Centers for Disease Control and prevention. Emergency Preparedness and Response. Multisystem Inflammatory Syndrome in Children (MIS-C) Associated with Coronavirus Disease 2019 (COVID-19). Accessed 1 December 2021. https://emergency.cdc.gov/han/2020/han00432.asp

 TABLE 1. ICD-10 diagnostic codes used to identify possible cases of MIS-C

TABLE 2. "List of reasons for visit" used to query the chief complaint field of ESSENCE to identify posible cases of MIS-C

You also may be interested in...

Article
May 1, 2019

Absolute and relative morbidity burdens attributable to various illnesses and injuries, active component, U.S. Armed Forces, 2018

A U.S. naval officer listens through his stethoscope to hear his patient’s lungs at Camp Schwab in Okinawa, Japan in 2018. (Photo courtesy of U.S. Marine Corps) photo by Lance Cpl. Cameron Parks)

In 2018, mental health disorders accounted for the largest proportions of the morbidity and healthcare burdens that affected the pediatric and younger adult beneficiary age groups. Among adults aged 45–64 years, musculoskeletal diseases accounted for the most morbidity and healthcare burdens, and among adults aged 65 years or older, cardiovascular ...

Article
May 1, 2019

Absolute and relative morbidity burdens attributable to various illnesses and injuries, non-service member beneficiaries of the Military Health System, 2018

A senior airman of 366th Medical Support Squadron pediatric clinic checks vitals of the child of its service member at Mountain Home Air Force Base in Idaho. (Photo courtesy of U.S. Air Force)

In 2018, mental health disorders accounted for the largest proportions of the morbidity and healthcare burdens that affected the pediatric and younger adult beneficiary age groups. Among adults aged 45–64 years, musculoskeletal diseases accounted for the most morbidity and health care burdens, and among adults aged 65 years or older, cardiovascular ...

Article
Apr 1, 2019

Update: Heat Illness, Active Component, U.S. Armed Forces, 2018

Drink water the day before and during physical activity or if heat is going to become a factor. (Photo Courtesy: U.S. Air Force)

In 2018, there were 578 incident diagnoses of heat stroke and 2,214 incident diagnoses of heat exhaustion among active component service members. The overall crude incidence rates of heat stroke and heat exhaustion diagnoses were 0.45 cases and 1.71 cases per 1,000 person-years, respectively. In 2018, subgroup-specific rates of incident heat stroke ...

Article
Apr 1, 2019

Incidence, Timing, and Seasonal Patterns of Heat Illnesses During U.S. Army Basic Combat Training, 2014–2018

U.S. Marines participate in morning physical training during a field exercise at Marine Corps Base Camp Pendleton, California. (Photo Courtesy: U.S. Marine Corps)

Risk factors for heat illnesses (HIs) among new soldiers include exercise intensity, environmental conditions at the time of exercise, a high body mass index, and conducting initial entry training during hot and humid weather when recruits are not yet acclimated to physical exertion in heat. This study used data from the Defense Health Agency’s ...

Article
Apr 1, 2019

Update: Exertional Rhabdomyolysis, Active Component, U.S. Armed Forces, 2014–2018

U.S. Marines sprint uphill during a field training exercise at Marine Corps Air Station Miramar, California. to maintain contact with an aviation combat element, teaching and sustaining their proficiency in setting up and maintaining communication equipment.  (Photo Courtesy: U.S. Marine Corps)

Among active component service members in 2018, there were 545 incident diagnoses of rhabdomyolysis likely due to exertional rhabdomyolysis, for an unadjusted incidence rate of 42.0 cases per 100,000 person-years. Subgroup-specific rates in 2018 were highest among males, those less than 20 years old, Asian/Pacific Islander service members, Marine ...

Article
Apr 1, 2019

Update: Exertional Hyponatremia, Active Component, U.S. Armed Forces, 2003–2018

Drink water the day before and during physical activity or if heat is going to become a factor. (Photo Courtesy: U.S. Air Force)

From 2003 through 2018, there were 1,579 incident diagnoses of exertional hyponatremia among active component service members, for a crude overall incidence rate of 7.2 cases per 100,000 person-years (p-yrs). Compared to their respective counterparts, females, those less than 20 years old, and recruit trainees had higher overall incidence rates of ...

Article
Apr 1, 2019

Modeling Lyme Disease Host Animal Habitat Suitability, West Point, New York

A deer basks in the morning sun at Joint Base San Antonio-Fort Sam Houston, Texas.  (Photo Courtesy: U.S. Air Force)

As the most frequently reported vector-borne disease among active component U.S. service members, with an incidence rate of 16 cases per 100,000 person-years in 2011, Lyme disease poses both a challenge to health care providers in the Military Health System and a threat to military readiness. Spread through the bite of an infected blacklegged tick, ...

Article
Mar 1, 2019

Brief Report: Male Infertility, Active Component, U.S. Armed Forces, 2013–2017

Sperm is the male reproductive cell  Photo: iStock

Infertility, defined as the inability to achieve a successful pregnancy after 1 year or more of unprotected sexual intercourse or therapeutic donor insemination, affects approximately 15% of all couples. Male infertility is diagnosed when, after testing both partners, reproductive problems have been found in the male. A male factor contributes in part ...

Article
Mar 1, 2019

Vasectomy and Vasectomy Reversals, Active Component, U.S. Armed Forces, 2000–2017

Sperm is the male reproductive cell  Photo: iStock

During 2000–2017, a total of 170,878 active component service members underwent a first-occurring vasectomy, for a crude overall incidence rate of 8.6 cases per 1,000 person-years (p-yrs). Among the men who underwent incident vasectomy, 2.2% had another vasectomy performed during the surveillance period. Compared to their respective counterparts, the ...

Article
Mar 1, 2019

Sexually Transmitted Infections, Active Component, U.S. Armed Forces, 2010–2018

Anopheles merus

This report summarizes incidence rates of the 5 most common sexually transmitted infections (STIs) among active component service members of the U.S. Armed Forces during 2010–2018. Infections with chlamydia were the most common, followed in decreasing order of frequency by infections with genital human papillomavirus (HPV), gonorrhea, genital herpes ...

Article
Mar 1, 2019

Testosterone Replacement Therapy Use Among Active Component Service Men, 2017

Image of Marines carrying a wooden log for physical fitness. Click to open a larger version of the image.

This analysis summarizes the prevalence of testosterone replacement therapy (TRT) during 2017 among active component service men by demographic and military characteristics. This analysis also determines the percentage of those receiving TRT in 2017 who had an indication for receiving TRT using the 2018 American Urological Association (AUA) clinical ...

Article
Feb 1, 2019

Update: Malaria, U.S. Armed Forces, 2018

Anopheles merus

Malaria infection remains an important health threat to U.S. service mem­bers who are located in endemic areas because of long-term duty assign­ments, participation in shorter-term contingency operations, or personal travel. In 2018, a total of 58 service members were diagnosed with or reported to have malaria. This represents a 65.7% increase from ...

Article
Feb 1, 2019

Update: Incidence of Glaucoma Diagnoses, Active Component, U.S. Armed Forces, 2013–2017

Glaucoma

Glaucoma is an eye disease that involves progressive optic nerve damage and vision loss, leading to blindness if undetected or untreated. This report describes an analysis using the Defense Medical Surveillance System to identify all active component service members with an incident diagnosis of glaucoma during the period between 2013 and 2017. The ...

Article
Feb 1, 2019

Re-evaluation of the MSMR Case Definition for Incident Cases of Malaria

Anopheles merus

The MSMR has been publishing the results of surveillance studies of malaria since 1995. The standard MSMR case definition uses Medical Event Reports and records of hospitalizations in counting cases of malaria. This report summarizes the performance of the standard MSMR case definition in estimating incident cases of malaria from 2015 through 2017. ...

Article
Feb 1, 2019

Outbreak of Acute Respiratory Illness Associated with Adenovirus Type 4 at the U.S. Naval Academy, 2016

Malaria case definition

Human adenoviruses (HAdVs) are known to cause respiratory illness outbreaks at basic military training (BMT) sites. HAdV type-4 and -7 vaccines are routinely administered at enlisted BMT sites, but not at military academies. During Aug.–Sept. 2016, U.S. Naval Academy clinical staff noted an increase in students presenting with acute respiratory ...

Skip subpage navigation
Refine your search
Last Updated: July 11, 2023
Follow us on Instagram Follow us on LinkedIn Follow us on Facebook Follow us on X Follow us on YouTube Sign up on GovDelivery