Skip to main content

Military Health System

Brief Report: Prevalence of Hepatitis C Virus Infections in U.S. Air Force Basic Military Trainees Who Donated Blood, 2017–2020

Image of U.S. Army Staff Sgt. Brandon Sousa, 424th Engineer Vertical Construction Company, donates blood to the 379th Expeditionary Medical Group’s Blood Support Center, Aug. 30, 2021, at Al Udeid Air Base, Qatar. The blood support center conducted a walking blood bank to collect blood from prescreened and cleared donors. The blood was sent downrange to support Afghanistan evacuation operations. The DoD is committed to supporting the U.S. State Department in the departure of U.S. and allied civilian personnel from Afghanistan, and to evacuate Afghan allies to safety. (U.S. Air Force photo by Senior Airman Kylie Barrow). U.S. Army Staff Sgt. Brandon Sousa, 424th Engineer Vertical Construction Company, donates blood to the 379th Expeditionary Medical Group’s Blood Support Center, Aug. 30, 2021, at Al Udeid Air Base, Qatar. The blood support center conducted a walking blood bank to collect blood from prescreened and cleared donors. The blood was sent downrange to support Afghanistan evacuation operations. The DoD is committed to supporting the U.S. State Department in the departure of U.S. and allied civilian personnel from Afghanistan, and to evacuate Afghan allies to safety. (U.S. Air Force photo by Senior Airman Kylie Barrow)

Recommended Content:

Medical Surveillance Monthly Report

Background

Chronic infection with hepatitis C virus (HCV) can cause significant morbidity to individuals due to inflammatory damage to the liver. This chronic inflammatory damage can lead to further complications, including cirrhosis, hepatocellular carcinoma, and fulminant liver failure. In the military, HCV presents a concern for fitness for duty, readiness, and health care costs of its members.

In the U.S., prevalence of chronic HCV infection is approximately 1%.1 From 2010–2019, estimated annual acute HCV incidence increased 387%2; increased detection was driven at least in part by improved and expanded testing recommendations as well as increased injection drug use within the opioid abuse epidemic.3,4 During this timeframe, the majority of new HCV infections occurred in those aged 20–39 (which approximates the ages of those joining the military).2

In 2020, the American Association for the Study of Liver Diseases (AASLD),5 U.S. Preventive Services Task Force (USPSTF),6 and Centers for Disease Control and Prevention (CDC)7 expanded recommendations for HCV infection screening to include all adults age 18 years or older (and for all pregnant women during each pregnancy) because of cost effectiveness, limited success of risk-based screening, and availability of curative treatment.

Active HCV infection disqualifies an individual from military accession because its proper clinical management conflicts with initial training and mission readiness. Three disqualifying criteria for active or recent HCV infection include: history of chronic HCV without successful treatment or without documentation of cure 12 months after completion of a full course of therapy; acute infection within the preceding 6 months; or persistence of symptoms or evidence of impaired liver function. Force screening for HCV is not currently performed during U.S. Air Force (USAF) Basic Military Training (BMT) although screening is completed for other viral infections (including HIV, hepatitis A, and hepatitis B). As a result, the true prevalence of chronic HCV infection cannot be ascertained in the basic trainee population. However, the prevalence can be estimated based on the number of HCV infections confirmed following positive screening during trainee blood donations.

Trainees voluntarily donate blood near the end of BMT and are thus able to donate only once while at BMT. Concurrent testing for HCV antibody and HCV RNA occurs at the time of blood donation. If a trainee's blood tests positive for HCV antibody but negative for HCV RNA, a third generation enzyme immunoassay (EIA) is used for confirmation. A positive test for HCV antibody in addition to either a positive HCV RNA or EIA test indicates active infection. Alternatively, a positive HCV antibody test in an individual with negative RNA and EIA tests typically denotes a cleared infection.

From Nov. 2013 through April 2016, the estimated prevalence of HCV infection among volunteer recruit blood donors at Joint Base San Antonio (JBSA)-Lackland Blood Donor Center was 0.007%.8 The goal of this inquiry was to estimate the most recent prevalence of HCV infections within the USAF basic training population during 2017–2020.

Methods

The JBSA-Lackland Blood Donor Center was queried for the results of HCV screening for all basic military trainees who donated blood between Jan. 1, 2017 and Dec. 31, 2020. All other blood donations (those from individuals other than basic trainees) during this time period were excluded. HCV prevalence in those who donated blood was calculated using the total trainee donations as the denominator. Since trainees are only able to donate once before departing BMT, these donations represent unique trainees. The numerator included those who screened positive upon donation and were also confirmed to have active infection upon subsequent testing. Positive HCV cases were ascertained from a local database, which included demographic, diagnostic, and laboratory data for all USAF recruits, maintained by Trainee Health Surveillance. This database was queried for International Classification of Diseases, 10th Revision (ICD-10) diagnostic codes K70–K77 (diseases of the liver) and B15–B19 (viral hepatitis); the codes for all hepatitides were initially utilized so as to conduct a wide search in case of coding errors. A possible case was defined as a trainee receiving a qualifying ICD-10 code in any diagnostic position during an outpatient medical encounter and was restricted to 1 case per person during the surveillance period. The electronic medical records of possible cases were reviewed and those diagnosed with current HCV infection due to blood screening from BMT blood donation were counted as true cases. Such screened positive BMT cases were confirmed by comparing them to those reported by the Blood Donation Center. The Fisher's exact test for count data was used to compare the prevalence computed for the period from 2017 through 2020 to the prevalence during the period from 2013 through 2016.

Results

From 2017 through 2020, 29,615 unique individual trainees from USAF BMT donated blood (out of 146,325 total trainees attending BMT during that time) and had their blood donations screened for HCV. From this group, a total of 85 individuals screened positive for HCV antibodies; of these, 6 were confirmed to be positive for active HCV infection (positive HCV RNA or EIA) (Table). The prevalence of HCV in those BMT trainees who were screened from 2017 through 2020 was 0.0203% (6 of 29,615 screened) (data not shown), which is 3.1 times (p=.173) the prevalence of HCV infection in this population during 2013–2016 (0.0065%, 2 of 30,660 screened).8 Of note, during 2017–2020, one additional case of HCV in BMT was diagnosed clinically based on symptoms; however, this case was excluded in the prevalence calculation because it was not from a blood donation.

Editorial Comment

The prevalence of HCV infection in BMT trainee blood donors from 2017 through 2020 was 3.1 times the prevalence among trainees who donated from 2013 through 2016.8 While the difference in prevalence was not statistically significant (p=.173), it may reflect the recent increases in incidence among U.S. young adults, as noted by the CDC,2 perhaps due to increased injection drug use.3,4

This study is limited in that the screened blood came from only those trainees attempting to donate blood, so the data do not directly estimate HCV prevalence for all trainees as would be the case from a random sample of the entire BMT trainee population. If the prevalence in blood donors reflected that in basic trainees overall, there would have been approximately 30 active HCV infections among basic trainees during the 4 year period; and of these, only approximately 20% were detected through blood donor screening.

Instituting accession-wide HCV screening at USAF BMT by adding it to the current lab evaluation would be an efficient method of ensuring that all new USAF enlisted service members are up to date on this screening as recommended by USPSTF, CDC, and AASLD.

Author affiliations: 559th Trainee Health Squadron, JBSA-Lackland, TX (Maj Kasper, Capt Holland, and Maj Kieffer); Office of the Command Surgeon, Air Education and Training, JBSA-Randolph, TX (Maj Frankel); 59th Medical Wing, Science and Technology, JBSA-Lackland, TX (Ms. Cockerell); Air Force Medical Readiness Agency, Falls Church, VA (Lt Col Molchan).

Disclaimer: The views expressed are those of the authors and do not reflect the official views or policy of the Department of Defense or its Components. In addition, the opinions expressed on this document are solely those of the authors and do not represent endorsement by or the views of the United States Air Force, the Department of Defense, or the United States Government.

References

  1. Hofmeister MG, Rosenthal EM, Barker LK, et al. Estimating prevalence of hepatitis C virus infection in the United States, 2013–2016. Hepatology. 2019;69(3):1020–1031.
  2. Centers for Disease Control and Prevention. 2019 Viral Hepatitis Surveillance Report- Hepatitis C. Published July 2021. Accessed 9 Aug. 2021. https://www.cdc.gov/hepatitis/statistics/2019surveillance/HepC.htm
  3. Zibbell JE, Asher AK, Patel RC, et al. Increases in acute hepatitis C virus infection related to a growing opioid epidemic and associated injection drug use, United States, 2004 to 2014. Am J Public Health. 2018;108(2):175–181.
  4. Suryaprasad AG, White JZ, Xu F, et al. Emerging epidemic of hepatitis C virus infections among young nonurban persons who inject drugs in the United States, 2006-2012. Clin Infect Dis. 2014;59(10):1411–1419.
  5. Ghany MG, Morgan TR; AASLD-IDSA Hepatitis C Guidance Panel. Hepatitis C Guidance 2019 Update: American Association for the Study of Liver Diseases – Infectious Diseases Society of America recommendations for testing, managing, and treating hepatitis C virus infection. Hepatology. 2020;71(2):686–721.
  6. US Preventive Services Task Force; Owens DK, Davidson KW, et al. Screening for hepatitis C virus infection in adolescents and adults: US Preventive Services Task Force Recommendation Statement. JAMA. 2020;323(10):970–975.
  7. Schillie S, Wester C, Osborne M, Wesolowski L, Ryerson AB. CDC Recommendations for hepatitis C screening among adults - United States, 2020. MMWR Recomm Rep. 2020;69(2):1–17.
  8. Taylor DF, Cho RS, Okulicz JF, Webber BJ, Gancayco JG. Brief report: Prevalence of hepatitis B and C virus infections in U.S. Air Force basic military trainees who donated blood, 2013-2016. MSMR. 2017;24(12):20–22.

TABLE. Demographics and disposition of the 6 confirmed HCV cases identified through blood donation screening at Air Force Basic Military Training, 2017–2020

You also may be interested in...

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

Article
2/1/2019
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. Also explored was the potential surveillance value of including outpatient encounters with diagnoses of malaria or positive laboratory tests for malaria in the case definition. The study corroborated the relative accuracy of the MSMR case definition in estimating malaria incidence and provided the basis for updating the case definition in 2019 to include positive laboratory tests for malaria antigen within 30 days of an outpatient diagnosis.

Recommended Content:

Medical Surveillance Monthly Report

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

Article
2/1/2019
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 the 35 cases identi­fied in 2017. The relatively low numbers of cases during 2012–2018 mainly reflect decreases in cases acquired in Afghanistan, a reduction due largely to the progressive withdrawal of U.S. forces from that country. The percentage of cases of malaria caused by unspecified agents (63.8%; n=37) in 2018 was the highest during any given year of the surveillance period. The percent­age of cases identified as having been caused by Plasmodium vivax (10.3%; n=6) in 2018 was the lowest observed during the 10-year surveillance period. The percentage of malaria cases attributed to P. falciparum (25.9 %) in 2018 was similar to that observed in 2017 (25.7%), although the number of cases increased. Malaria was diagnosed at or reported from 31 different medical facilities in the U.S., Afghanistan, Italy, Germany, Djibouti, and Korea. Pro­viders of medical care to military members should be knowledgeable of and vigilant for clinical manifestations of malaria outside of endemic areas.

Recommended Content:

Medical Surveillance Monthly Report

Thyroid Disorders, Active Component, U.S. Armed Forces, 2008–2017

Article
12/1/2018
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)

This analysis describes the incidence and prevalence of five thyroid disorders (goiter, thyrotoxicosis, primary/not otherwise specified [NOS] hypothyroidism, thyroiditis, and other disorders of the thyroid) among active component service members between 2008 and 2017. During the 10-year surveillance period, the most common incident thyroid disorder among male and female service members was primary/NOS hypothyroidism and the least common were thyroiditis and other disorders of thyroid. Primary/NOS hypothyroidism was diagnosed among 8,641 females (incidence rate: 43.7 per 10,000 person-years [p-yrs]) and 11,656 males (incidence rate: 10.2 per 10,000 p-yrs). Overall incidence rates of all thyroid disorders were 3 to 5 times higher among females compared to males. Among both males and females, incidence of primary/NOS hypothyroidism was higher among non-Hispanic white service members compared with service members in other race/ethnicity groups. The incidence of most thyroid disorders remained stable or decreased during the surveillance period. Overall, the prevalence of most thyroid disorders increased during the first part of the surveillance period and then either decreased or leveled off.31.6 per 100,000 active component service members in 2017. Validation of ICD-9/ICD-10 diagnostic codes for MetS using the National Cholesterol Education Program Adult Treatment Panel III criteria is needed to establish the level of agreement between the two methods for identifying this condition.

Recommended Content:

Medical Surveillance Monthly Report

Incidence and Prevalence of the Metabolic Syndrome Using ICD-9 and ICD-10 Diagnostic Codes, Active Component, U.S. Armed Forces, 2002–2017

Article
12/1/2018

This report uses ICD-9 and ICD-10 codes (277.7 and E88.81, respectively) for the metabolic syndrome (MetS) to summarize trends in the incidence and prevalence of this condition among active component members of the U.S. Armed Forces between 2002 and 2017. During this period, the crude overall incidence rate of MetS was 7.5 cases per 100,000 person-years (p-yrs). Compared to their respective counterparts, overall incidence rates were highest among Asian/Pacific Islanders, Air Force members, and warrant officers and were lowest among those of other/unknown race/ethnicity, Marine Corps members, and junior enlisted personnel and officers. During 2002–2017, the annual incidence rates of MetS peaked in 2009 at 11.6 cases per 100,000 p-yrs and decreased to 5.9 cases per 100,000 p-yrs in 2017. Annual prevalence rates of MetS increased steadily during the first 11 years of the surveillance period reaching a high of 38.9 per 100,000 active component service members in 2012, after which rates declined slightly to 31.6 per 100,000 active component service members in 2017. Validation of ICD-9/ICD-10 diagnostic codes for MetS using the National Cholesterol Education Program Adult Treatment Panel III criteria is needed to establish the level of agreement between the two methods for identifying this condition.

Recommended Content:

Medical Surveillance Monthly Report

Adrenal Gland Disorders, Active Component, U.S. Armed Forces, 2002–2017

Article
12/1/2018

During 2002–2017, the most common incident adrenal gland disorder among male and female service members was adrenal insufficiency and the least common was adrenomedullary hyperfunction. Adrenal insufficiency was diagnosed among 267 females (crude overall incidence rate: 8.2 cases per 100,000 person-years [p-yrs]) and 729 males (3.9 per 100,000 p-yrs). In both sexes, overall rates of other disorders of adrenal gland and Cushing’s syndrome were lower than for adrenal insufficiency but higher than for hyperaldosteronism, adrenogenital disorders, and adrenomedullary hyperfunction. Crude overall rates of adrenal gland disorders among females tended to be higher than those of males, with female:male rate ratios ranging from 2.1 for adrenal insufficiency to 5.5 for androgenital disorders and Cushing’s syndrome. The highest overall rates of adrenal insufficiency for males and females were among non-Hispanic white service members. Among females, rates of Cushing's syndrome and other disorders of adrenal gland were 31.6 per 100,000 active component service members in 2017. Validation of ICD-9/ICD-10 diagnostic codes for MetS using the National Cholesterol Education Program Adult Treatment Panel III criteria is needed to establish the level of agreement between the two methods for identifying this condition.

Recommended Content:

Medical Surveillance Monthly Report

2018 #ColdReadiness Twitter chat recap: Preventing cold weather injuries for service members and their families

Fact Sheet
2/5/2018

To help protect U.S. armed forces, the Armed Forces Health Surveillance Branch (AFHSB) hosted a live #ColdReadiness Twitter chat on Wednesday, January 24th, 12-1:30 pm EST to discuss what service members and their families need to know about winter safety and preventing cold weather injuries as the temperatures drop. This fact sheet documents highlights from the Twitter chat.

Recommended Content:

Medical Surveillance Monthly Report | Winter Safety | Medical and Dental Preventive Care Fitness | Health Readiness & Combat Support

Demographic and Military Traits of Service Members Diagnosed as Traumatic Brain Injury Cases

Fact Sheet
3/30/2017

This fact sheet provides details on the demographic and military traits of service members diagnosed as traumatic brain injury (TBI) cases during a 16-year surveillance period from 2001 through 2016, a total of 276,858 active component service members received first-time diagnoses of TBI - a structural alteration of the brain or physiological disruption of brain function caused by an external force.

Recommended Content:

Armed Forces Health Surveillance Division | Medical Surveillance Monthly Report

Heat Illnesses by Location, Active Component, U.S. Armed Forces, 2012-2016 Fact Sheet

Fact Sheet
3/30/2017

This fact sheet provides details on heat illnesses by location during a five-year surveillance period from 2012 through 2016. 11,967 heat-related illnesses were diagnosed at more than 250 military installations and geographic locations worldwide. Three Army Installations accounted for close to one-third of all heat illnesses during the period.

Recommended Content:

Armed Forces Health Surveillance Division | Medical Surveillance Monthly Report

Rhabdomyolysis by Location, Active Component, U.S. Armed Forces, 2012-2016 Fact Sheet

Fact Sheet
3/30/2017

This fact sheet provides details on Rhabdomyolysis by location for active component, U.S. Armed Forces during a five-year surveillance period from 2012 through 2016. The medical treatment facilities at nine installations diagnosed at least 50 cases each and, together approximately half (49.9%) of all diagnosed cases.

Recommended Content:

Armed Forces Health Surveillance Division | Medical Surveillance Monthly Report
<< < ... 11 12 13 > >> 
Showing results 181 - 189 Page 13 of 13
Refine your search
Last Updated: October 18, 2022
Follow us on Instagram Follow us on LinkedIn Follow us on Facebook Follow us on Twitter Follow us on YouTube Sign up on GovDelivery