Health Department Releases Detailed Report on COVID-19 Variants

Detailed report includes latest information on variants of concern and interest in New York City, including geographic distribution

April 12, 2021 — The Health Department released detailed results of the sequencing and analysis being conducted in the City to identify emerging variants and and learn how these variants may be impacting public health.

The report includes details on the multiple variants of interest and variants of concern identified in NYC and contains an overview of key findings on B.1.526 (first identified in New York) and B.1.1.7 (first identified in the U.K.). The investigations combine laboratory and epidemiologic observations to characterize each variant.

Key findings include:

  • The proportion of variants of concern and variants of interest is increasing.
  • B.1.526 and B.1.1.7 variants are in all five boroughs.
    • B.1.526 cases are slightly more common in the Bronx and parts of Queens.
    • B.1.1.7 cases are slightly more common in southern Brooklyn, eastern Queens, and Staten Island.

The City continues to assess for differences in severity, risk for reinfection, or risk for impacting vaccine effectiveness that might be associated with variants. These ongoing efforts include:

  • Monitoring the number of hospitalizations and deaths that occur among patients with sequenced specimens that are caused by variants.
  • Identifying cases caused by variants where the case-patient had a previous positive diagnostic test for COVID-19 more than 90 days earlier. These cases are investigated to determine if they are likely to represent a reinfection, in order to determine if reinfection cases are more common in people that have been infected with one of the variants.
  • Matching data on cases caused by variants with Citywide Immunization Registry data to identify if the person was fully immunized prior to testing positive for COVID-19.

To date, reinfection cases and cases in people who were fully vaccinated are rare. It is too early to know if either of these variants are more likely to cause reinfection or vaccine breakthrough compared to other previously circulating variants. The increase in proportion of cases that are variants indicates that they may be more transmissible, so New Yorkers should continue to get vaccinated when eligible and adhere to the Core Four: wear a face covering, maintain distance from others, stay home if sick and practice good hand hygiene.



MEDIA CONTACT: Patrick Gallahue / Michael Lanza,