Page 65 - JSOM Fall 2021

TABLE 2 Symptoms Based on Quarantine Status, Military Occupational Specialty, and Tobacco Use
No Symptoms, No. (%) Symptoms, No. (%) Respiratory Neurologic Systemic GI
Quarantined
No 109 (47) 124 (53) 79 3 47 16
Yes 11 (35.5) 20 (64.5) 15 2 13 4
Total 120 (45.5) 144 (54.5) 94 5 60 20
MOS Category
Combat Arms 59 (40) 87 (60) 56 4 35 11
Medical 11 (32) 23 (68) 17 1 13 7
Support 50 (59.5) 34 (40.5) 21 5 12 2
Total 120 (45.5) 144 (54.5) 94 0 60 20
Tobacco Use
No 75 (47.5) 83 (52.5) 49 3 31 5
Yes 45 (42.5) 61 (57.5) 45 2 29 15
Total 120 (45.5) 144 (54.5) 94 5 60 20
Respiratory = cough, runny nose, shortness of breath, sore throat; neurologic = new loss of taste or smell, headache, systemic = fever or chills,
fatigue, muscle of body aches, gastrointestinal (GI) = nausea or vomiting, diarrhea, MOS = military occupational specialty.

a significant amount of work time and quality lost. Follow- Other explanations for the low prevalence of positive antibody
ing CDC guidance of 14 days’ quarantine for trace contacts, testing are loss of antibodies over time and/or false negatives.
31 Soldiers completed 434 days of quarantine, 17 of whom The question of loss of antibodies remains debatable, but is
were combat arms Soldiers, in which primary duties require a possibility. Long et al. and Ibarrondo et al. trended SARS-
in- person execution. CoV-2 IgG testing in 37 asymptomatic and 37 symptomatic
COVID-19 participants. They found that 40% and 12.9%
A total of 144 of 264 (54.5%) endorsed one or more symp- became seronegative within 2–3 months, respectively. Those
toms of potential COVID-19 since January 2020 (Table 2). with mild or asymptomatic illness were more likely to become
The most common symptoms were headache (35%), rhinor- seronegative in the future. 11,12 On the other hand, Wajnberg
rhea (34%), cough (35%), and sore throat (31%). The least et al. trended 121 participants with moderate range SARS-
common symptom of the respondents was a new loss of taste CoV-2 antibody titer levels with only one individual becoming
or smell. Of those quarantined as a trace contact, 20 of 31 seronegative at day 82 and two becoming seronegative at day
(65%) endorsed symptoms of potential COVID-19. Of oc- 148. The sensitivity of antibody testing will be discussed in
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cupations, the medical MOS had the highest percentage en- limitations to follow.
dorsing symptoms with 23 of 34 (68%), followed by combat
arms MOS with 87 of 146 (60%). The combat support and With 55% of the participants self-reporting symptoms of po-
service support MOS Soldiers followed thereafter with 34 of tential COVID-19 since January 2020, there are many expla-
84 (41%) endorsing symptoms. Tobacco/vaping use and being nations other than COVID-19, such as other infectious diseases
quarantined had no significant association with any symptom (e.g., influenza, gastroenteritis) and noninfectious conditions
development with p-values of .42 and .17, respectively. (e.g., seasonal allergies, tension headache). The symptoms of
COVID-19 are nonspecific compared to other common infec-
tious illnesses and medical conditions, which make clinical
Discussion
distinction difficult without confirmatory laboratory testing.
The primary outcome is only one positive SARS-CoV-2 anti- In addition, participants self-reported symptoms and may not
body test. This is surprising as the researchers expected higher have ever been evaluated by a medical provider for the symp-
numbers of positive antibody tests given the number of re- toms, further decreasing the likelihood symptoms are related
spondents reporting positive symptoms, those quarantined as to COVID-19. Of all symptoms, anosmia and ageusia was
a close contact, and the high COVID-19 infection prevalence least reported by participants with 7 (3%) of respondents, one
in the surrounding community during this timeframe. of which was positive for SARS-CoV-2 antibody. Interestingly,
anosmia and ageusia may be a more distinguishable clinical
The low prevalence of previous COVID-19 infection in this symptom of previous and current COVID-19 infection. The
sample could be explained by the brigade’s strict control mea- American Academy of Otolaryngology COVID-19 Anosmia
sures to prevent infection and spread. Any Soldiers (and their Reporting Tool found 73% of SARS-CoV-2 NAAT positive
roommates) endorsing symptoms of COVID-19 were isolated patients reported anosmia and ageusia. Peyrony et al.’s obser-
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within a day of symptoms with telemedical evaluation by unit vational study of 400 emergency department patients demon-
medical providers. Social distancing with mask wear was man- strated a specificity of 0.98 and positive predictive value of
dated, outdoor training was limited to small groups, and travel 0.91 for anosmia and ageusia. 15
to endemic COVID-19 areas required command approval. In
addition, 12% of respondents had been quarantined as a close Limitations are inherent in the antibody test. The Elecsys Anti-
contact with only one positive antibody test, demonstrating SARS-CoV-2 is under the US FDA Emergency Use Authoriza-
effective quarantine and isolation measures. The results could tion (EUA). While studies of both CLIA and this specific Elecsys
be generalizable to other operational units on Joint Base Lewis Anti-SARS-CoV-2 test have strong sensitivities and specifici-
McChord given similar control measures and demographics, ties, it has not been studied extensively in healthy, young out-
but not to other bases. patient populations. 16–18 Thus, there is a possibility that there

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