[Archived] Alexandria Health Department Provides Update on COVID-19 ZIP Code, Race, Ethnicity and Age Data from November

­­For Immediate Release: December 18, 2020

The Alexandria Health Department (AHD) has published the latest analysis of COVID-19 case data including cumulative figures and new cases by ZIP code, race, ethnicity and age groups.

Updated ZIP Code Data

As of December 1, the Virginia Department of Health (VDH) has reported the following cumulative COVID-19 cases, and the City of Alexandria has provided the estimated population for each local ZIP code to compare the number of cases per 1,000 residents.

Cumulative ZIP Code Data Summaries (by month)

 ¹ The positivity rate is the number of confirmed cases divided by the number of tests.

² ZIP code 22206 is mostly in Arlington County; the City of Alexandria portion of data for 22206 is not provided, therefore the numbers and calculations would not be reliable for reporting for Alexandria.

³ ZIP codes 22311 and 22312 are shared between the City of Alexandria and Fairfax County. The number of cases and number of people tested presented in this table, and accompanying calculations, are for the entire ZIP code. Cases per 1,000 Alexandrians cannot be reliably calculated.

⁴ Data is cumulative from the onset of the pandemic to May 7, and includes cases and tests over a period greater than one month.

The following graph depicts the cumulative total number of PCR tests completed, total number of positive cases, and percent positivity over time by ZIP code. 

Significant Changes since October Analysis, Using Cumulative Data

As expected with ongoing community transmission of COVID-19, there has been an increase in cumulative positive cases per 1,000 residents. The range of rates in the October analysis was 9.8 (in 22314) to 54.1 (in 22305), and the range in the November analysis is 13.0 to 64.1, with the same ZIP codes having the highest and lowest confirmed cases.

Only one ZIP Code (22301) experienced an increase in cumulative positivity rate since last month's analysis. However, with a cumulative positivity rate of 3.7%, ZIP code 22301 continues to have the lowest rate of all Alexandria ZIP Codes since May. Positivity rates measure the percentage of tests conducted in a population that are positive. This measure is influenced by a number of factors, including how many tests are conducted, who is being tested, and how rapidly the virus is spreading. Percent positivity calculations will also vary depending on how individuals with multiple positive tests are included in the formula. The CDC describes in more detail the different methodological choices of this calculation. While there is no perfect measure to describe the impact of COVID-19 infections during this pandemic, positivity rate is a widely-used metric despite its limitations. Data presented in the table are based on information shared by VDH and subject to change based on updates.

In the October analysis, the cumulative positivity rate ranged from 3.6% to 14.3%. In the November analysis, the range is 3.7% to 13.4%. The ZIP code with the highest cumulative positivity rates since May remains 22305, but this ZIP code has also experienced a 75.8% reduction in its cumulative positivity rate since the initial analysis.

Monthly ZIP Code Data Summaries

It is also important to look at the data monthly to understand the current state of the pandemic. The following analysis is a monthly snapshot of new cases and tests since the prior month’s report. This month’s report is based on data reported by VDH as of December 1.

¹ The positivity rate is the number of confirmed cases divided by the number of tests.

² ZIP code 22206 is mostly in Arlington County; the Alexandria portion of data for 22206 is not provided, therefore the numbers and calculations would not be reliable for reporting for Alexandria.

³ ZIP codes 22311 and 22312 are shared between Alexandria and Fairfax County. The number of cases and number of people tested presented in this table, and accompanying calculations, are for the entire ZIP code. Cases per 1,000 Alexandrians cannot be reliably calculated.

⁴ Data is cumulative from the onset of the pandemic to May 7 and includes cases and tests over a period greater than one month.

Analysis of Monthly Data 

All ZIP codes have experienced increases in positivity rates from the October report to the November report, which is expected based on the current regional and nationwide surge in cases.

The total number of PCR tests in the November analysis period was 17,555, which is 7,000 more than the prior month. The number of tests obtained by residents increased in all ZIP codes in November.

Since the beginning of the pandemic, AHD has worked with Alexandria’s health care providers and community partners to increase both testing availability and testing awareness across all ZIP codes in Alexandria. Prevention of new infections remains a priority, and timely testing is one part of the multipronged pandemic response strategy. It is important for all members of the community to stay home when ill, practice physical distancing, wear masks correctly and continuously in public, wash hands frequently, and cooperate with case investigations and contact tracing when called by public health staff.

Disproportionate Impact of COVID-19 by Race and Ethnicity

Everyone is at risk for COVID-19, but it has disproportionately affected vulnerable populations throughout the United States, in Virginia, regionally, and within Alexandria, due to underlying systemic inequities. VDH has published data on COVID-19 cases by race and ethnicity since the middle of June. The following tables and graphs present the cumulative case data by month.

Cumulative Race and Ethnicity Data Summary

Individuals who identify as Latino or Hispanic make up 16.8% of the population in Alexandria but represent 43.2% of the diagnosed COVID-19 infections as of December 1. There has been a decline in the proportion of cumulative COVID-19 infections diagnosed among Latinos over time.

Monthly New Case Race and Ethnicity Data

⁵ Interval data is calculated from cumulative data provided by VDH which is subject to changes.

When looking at COVID-19 cases reported from November 1 through December 1, 17.9% of cases were among residents who identify as Black, which is a decrease from the prior report’s 20.0%. Residents who identify as Latino or Hispanic comprised 32.8% of cases during the same period, which is a decrease from the prior report’s 39.8%. The percentage of newly reported cases of COVID-19 among people identifying as white decreased in this analysis, from 30.2% to 28.4%. It is important to keep in mind that the proportion of cases increased this month to 12.7% among those whose race was not reported. If cases were proportionate by population groups, AHD would expect to see whites with the highest number of cases and almost double the number of cases compared to the Black population.

Disproportionate Impact of COVID-19 by Age

When looking at cumulative data, the largest proportion of cases continue to be among those 30 to 39 years old, which is to be expected based on Alexandria’s population.

Cumulative Age Data Summary

Monthly New Case Age Data Summary

Those who are 30 to 39 years old represent the largest proportion of newly reported cases from November 1 to December 1. There was an increase in cases during this same time period among all age groups.

⁵ Interval data is calculated from cumulative data provided by VDH which is subject to changes.

What the Alexandria Health Department is Doing

AHD is a mission-driven organization whose response to this pandemic is consistent with its public health justice principles.

AHD activities in the past month to combat the COVID-19 pandemic include:

• Responded to cases and outbreaks in the community. AHD case investigators and contact tracers work seven days a week to help minimize the spread of COVID-19 infection.

• Provided technical support to Neighborhood Health to organize and coordinate regularly targeted testing events for communities who may have otherwise had limited access to testing and for those who have been exposed to a positive COVID-19 case. AHD analyzes data and identifies these communities based on need. There are eight testing events planned for December. AHD and the City maintain resources regarding local testing facilities where Alexandrians can get tested any day of the week.

• Supported City agencies, faith-based organizations, schools, daycares, and governmental leadership with recommendations based on up-to-date COVID-19 epidemiology and research.

• Responded to complaints about businesses not adhering to the state executive order on masks and supported businesses in their commitment to the ALX Promise.

• Provided personal protective equipment (PPE) to Alexandria healthcare providers that offer COVID-19 testing. With volunteer support from the Alexandria Medical Reserve Corps, AHD distributes surgical masks, medical gowns, medical gloves and face shields free of charge when supplies are available

• Continued AHD’s COVID-19 vaccination preparations, using the principles of maximizing benefits and reducing harm, promoting justice, mitigating health inequities, and maintaining transparency.