Prior to the COVID-19 pandemic, underinvestment in public health was widespread in the US, with as little as 1.5% of the US government’s $3.6 trillion annual health budget directed towards population-level public health activities. Simultaneously, numerous studies had also documented how social vulnerability was a key driver in health inequities in the context of disasters such as hurricanes, heat waves, and wildfires. When SARS-CoV-2 emerged in 2020, the pre-existing problems of public health underinvestment and social-vulnerability-driven-health-inequities exacerbated impacts of the pandemic in the US. For example, the contact tracing workforce in the US in 2020 fell short of the estimated 100,000 contact tracers required to address COVID-19, which would have required an additional $3.6 billion in emergency funding from Congress. Additionally, evidence emerged that vulnerable Americans were disproportionately impacted by COVID-19 in terms of clinical outcomes and social wellbeing. Thus, we sought to understand the impact of the pandemic in Philadelphia, especially in the context of vulnerable residents. We evaluated the efficacy of a key pandemic response, contact tracing. We found that one third of COVID-19 cases and contacts interviewed by volunteer contact tracers between April 2020 – May 2021 experienced material hardships that would make it difficult for them to isolate or quarantine safely, and such hardship was significantly less common among White compared to Black participants (OR: 0.20, CI 0.16 - 0.25). Furthermore, the volunteer contact tracers conducting these calls, many of whom were students of the health professions, developed an understanding regarding current gaps in both public health infrastructure and support for vulnerable populations while conducting this work. We explored our research question further by investigating transmission dynamics of SARS-CoV-2 over time by vulnerability. We found that COVID-19 positivity, hospitalization, mortality, and estimated Alpha incidence rates were significantly positively associated with the more vulnerable communities. The relative risks of COVID-19 related hospitalization, death, and Alpha incidence between more and less vulnerable communities were 2.25 (95%CI: 2.02-2.51), 2.16 (95%CI: 1.70-2.74), and 4.77 (95%CI: 3.96-5.74), respectively. Combined, these results led us to conclude that vulnerable Philadelphians experienced large health inequities during the COVID-19 pandemic, illustrating the need for the implementation of policies addressing social vulnerability in Philadelphia.