We still don't know key elements about the Covid outbreak affecting the White House. This is what needs to happen to assess the outbreak's impact and stop continued spread. 6 steps in an epidemiologic investigation:

Step 1: Establish the case definition: person, place, and time. For example, someone who had contact with anyone in the White House after September 18 and has a positive test for Covid (confirmed) or symptoms consistent with Covid (suspected).

Step 2: Find all who meet the case definition through active surveillance.

Step 3: Make an "epidemic curve" showing cases by time of onset. (Anyone have one for this cluster?)

Step 4: Analyze risk factors for infection and explore hypotheses regarding the people and places that may have resulted in spread of infection.

Step 5: Take action based on the most plausible hypothesis in order to limit further spread of the infection.

Step 6: Assess the impact of the intervention, reevaluate the data, and optimize interventions. Repeat.

Outbreak control works, if done quickly and well.