Effectiveness of the Ad26.COV2.S vaccine in health-care workers in South Africa (the Sisonke study): results from a single-arm, open-label, phase 3B, implementation study

Durable antibody responses elicited by 1 dose of Ad26.COV2.S and substantial increase after boosting: 2 randomized clinical trials

“…We previously reported that a single dose of Ad26.COV2.S is immunogenic and provides robust efficacy against severe/critical COVID-19 and COVID-19–related hospitalization and death, including in areas where the Beta variant had high prevalence [4] , [12] . Additionally, data from several real-world studies [13] , [14] , [15] , [16] , [17] demonstrated effectiveness of a single dose of Ad26.COV2.S against COVID-19–related hospitalization and death during a period of high prevalence of the Delta variant.…”

Effectiveness of Ad26.COV2.S and BNT162b2 Vaccines against Omicron Variant in South Africa

“…Starting in October 2021, health care workers who were participating in phase 3b of the Sisonke study of the early vaccine access program 3 were eligible to receive a second dose of the Ad26.COV2.S vaccine (Fig. S1 in the Supplementary Appendix , available with the full text of this letter at NEJM.org).…”

Axillary lymph node characteristics in breast cancer patients versus post-COVID-19 vaccination: Overview of current evidence per imaging modality

“…Axillary lymphadenopathy was frequently observed in patients after the introduction of COVID-19 vaccinations, although multiple studies also confirmed occurrence of lymphadenopathy in patients diagnosed with COVID-19 pneumonia (albeit relatively uncommon when compared to other viral pneumonia), [5] , [6] , [7] . The COVID-19 vaccines are commonly injected intramuscularly in the deltoid muscle of the (preferably) non-dominant arm, causing relatively frequent lymph node swelling at physical examination in the ipsilateral axilla and supraclavicular region in up to 16% [8] , [9] , [10] .…”