In an effort to monitor the spread of COVID-19, New York City agencies receive reports of positive cases through multiple data systems that help to identify school-based contacts in collaboration with teachers and administrators who work at those schools.

In the fall of 2021, New York City experienced a surge in COVID-19 cases due to the Delta variant. An analysis was conducted utilizing the available databases to help assess rates of transmission within the public school system and to answer the question, “If a person with COVID-19 is present in school, how likely is it that they will transmit infection to other people in that school?”

In a paper written for JAMA Network Open, Executive Director Dr. Ted Long and others, talk about the rates of transmission during this time period using statistical methods.

Read more about the transmission of COVID-19 in New York City Public schools from October to December 2021 here: https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2792541

Key points:

• The analysis was restricted to index cases identified from October 10 to December 5, 2021, because of the changing contact definitions and vaccination data at the beginning of the school year and the emergence of community transmission of the Omicron variant during the week of December 5.
• From October to December 2021, the secondary attack rate (referring to the probability that infection can occur between susceptible people in a specific group) of COVID-19 in New York City public schools was 0.7%. In fall 2021, the secondary attack rate was comparable to that of fall 2020 in New York City, lower than that in multiple North Carolina schools when the Delta variant was dominant and much lower than household transmission.
• It should be noted that definitive conclusions about vaccine effectiveness should not be made after this assessment because neither vaccination status nor testing for all exposed contacts was fully complete.