Background
Comparing humoral responses in SARS-CoV-2 vaccinees, those with SARS-CoV-2 infection, or combinations of vaccine/infection (‘hybrid immunity’), may clarify predictors of vaccine immunogenicity.
Methods
We studied 2660 U.S. Military Health System beneficiaries with a history of SARS-CoV-2 infection-alone (n = 705), vaccination-alone (n = 932), vaccine-after-infection (n = 869), and vaccine-breakthrough-infection (n = 154). Peak anti-spike-IgG responses through 183 days were compared, with adjustment for vaccine product, demography, and comorbidities. We excluded those with evidence of clinical or sub-clinical SARS-CoV-2 reinfection from all groups.
Results
Multivariable regression results indicated vaccine-after-infection anti-spike-IgG responses were higher than infection-alone (p < 0.01), regardless of prior infection severity. An increased time between infection and vaccination was associated with a greater post-vaccination IgG response (p < 0.01). Vaccination-alone elicited a greater IgG response, but more rapid waning of IgG (p < 0.01), compared to infection-alone (p < 0.01). BNT162b2 and mRNA-1273 vaccine-receipt was associated with greater IgG responses compared to JNJ-78436735 (p < 0.01), regardless of infection history. Those with vaccine-after-infection or vaccine-breakthrough-infection had a more durable anti-spike-IgG response compared to infection-alone (p < 0.01).
Conclusions
Vaccine-receipt elicited higher anti-spike-IgG responses than infection-alone, although IgG levels waned faster in those vaccinated (compared to infection-alone). Vaccine-after-infection elicits a greater humoral response compared to vaccine or infection alone; and the timing, but not disease severity, of prior infection predicted these post-vaccination IgG responses. While differences between groups were small in magnitude, these results offer insights into vaccine immunogenicity variations that may help inform vaccination timing strategies.
The patient had no contraindications for oral TXA. Given the high concern for PIH, she was prescribed TXA 650 mg daily and clobetasol 0.05% cream twice daily. The clobetasol cream was discontinued after one week and TXA was discontinued after eight weeks. Sixteen weeks later, she presented with normalappearing skin. Her previous similar episode of PIH had been treated with clobetasol 0.05% cream for 2 weeks followed by hydroquinone 4% and monthly light chemical peels, leading to resolution only after six months. We believe the addition of TXA was responsible for her quick recovery without PIH, and without multiple chemical peels or prolonged use of hydroquinone (Figure 2). CASE 2 A 20-year-old woman with Fitzpatrick skin type 4, presented with acne, acne excorie, and PIH (Figure 3, left side). She was treated with topicals (sunscreen and tretinoin 0.05%) and daily spironolactone 100 mg. A series of light chemical peels was planned. She was prophylactically prescribed oral TXA 650 mg daily for her ongoing excoriation and concern that the peels would exacerbate her current PIH. Over a period of 2.5 years, she completed nine exfoliative chemical peels (Vitalize peels, Allergan, Irvine, CA) without any complications (Figure 3, right side). She did not develop any new PIH during this time despite continued excoriation.
The term “COVID arm” has been coined to describe a harmless delayed hypersensitivity reaction occurring approximately a week after administration of the novel SARS-CoV-2 mRNA vaccine. It appears as a red, warm, pruritic, indurated, or swollen area in the vicinity of the vaccine site. These reactions, especially if accompanied by systemic symptoms, have been mistaken for cellulitis. We report 3 cases of COVID arm, 2 of which were mistaken for cellulitis. Distinguishing features of COVID arm from cellulitis include pruritus as a common finding, occurrence approximately a week after vaccination, a lack of progression of symptoms, rapid response to topical steroids, and/or spontaneous resolution usually over 4 to 5 days. Practice Points: • Patients receiving SARS-CoV-2 vaccines may experience delayed hypersensitivity reactions characterized by erythema, swelling, and itching occurring near the vaccination site (COVID arm), approximately a week after vaccination. • Clinicians can distinguish SARS-CoV-2 vaccine reactions from cellulitis by the time of onset (approximately a week vs 5 days), by the lack of progression of symptoms, and resolution over 4 to 5 days. • Severe cases of COVID arm may be treated with topical steroids.
Common callouses are formed by the accumulation of keratinocytes in the stratum corneum in response to excess pressure or friction. We report 2 cases of unusual callous formation and an additional 25 more sequential cases that were due to excessive cell phone grip.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.