# weekly oscillation of new daily cases **URL:** \ **Category:** The Quarantine Zone\ **Tags:** covid-quarantine\ **Created:** [May 4, 2020, 12:29pm UTC](https://boards.straightdope.com/t/weekly-oscillation-of-new-daily-cases/853121 "2020-05-04T12:29:18Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Sigene](https://avatars.discourse-cdn.com/v4/letter/s/df788c/32.png) [@Sigene](https://boards.straightdope.com/u/Sigene)\ **Post date:** [May 4, 2020, 12:29pm UTC](https://boards.straightdope.com/t/weekly-oscillation-of-new-daily-cases/853121/1 "2020-05-04T12:29:18Z")
I’ve noted that there seems to be about a 7 day oscillating rise and fall of daily reported cases on the worldometer site for the U.S. [United States COVID - Coronavirus Statistics - Worldometer](https://www.worldometers.info/coronavirus/country/us/) It appears a bit in the daily death’s chart as well Is there an explanation for this? I’m going to guess its an artifact in how cases are reported rather than real. Or its just that sometimes data shows patterns where there really aren’t one. It seems that every friday there is a bit of a spike in reported cases. Has anyone else noted this and is there an explanation? I’ll claim naming rights if it hasn’t been reported before…“sigene oscillation” ---
**Author:** ![kanicbird](https://avatars.discourse-cdn.com/v4/letter/k/5f8ce5/32.png) [@kanicbird](https://boards.straightdope.com/u/kanicbird)\ **Post date:** [May 4, 2020, 1:15pm UTC](https://boards.straightdope.com/t/weekly-oscillation-of-new-daily-cases/853121/2 "2020-05-04T13:15:09Z")
My take on it (yes I’ve seen that too), is that people are less likely to go to a hospital and/or get tested on a weekend. even some testing facilities may be closed then. ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [May 4, 2020, 3:07pm UTC](https://boards.straightdope.com/t/weekly-oscillation-of-new-daily-cases/853121/3 "2020-05-04T15:07:46Z")
> [@Sigene](#): > > I’ve noted that there seems to be about a 7 day oscillating rise and fall of daily reported cases on the worldometer site for the U.S. [United States COVID - Coronavirus Statistics - Worldometer](https://www.worldometers.info/coronavirus/country/us/) > It appears a bit in the daily death’s chart as well > Is there an explanation for this? I’m going to guess its an artifact in how cases are reported rather than real. Or its just that sometimes data shows patterns where there really aren’t one. > It seems that every friday there is a bit of a spike in reported cases. > > Has anyone else noted this and is there an explanation? > I’ll claim naming rights if it hasn’t been reported before…“sigene oscillation” I’ve been wondering about this, too. It’s not just the US cases – every country shows these weird oscillations. ---
**Author:** ![Horatius](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/horatius/32/3572_2.png) [@Horatius](https://boards.straightdope.com/u/Horatius)\ **Post date:** [May 4, 2020, 6:17pm UTC](https://boards.straightdope.com/t/weekly-oscillation-of-new-daily-cases/853121/4 "2020-05-04T18:17:24Z")
I was thinking about this as well. In addition to the effects of reporting numbers on the weekend, there’ probably also an underlying weekly cycle in the actual infections. Even with the social distancing going on, most people who go out tend to go out on the same days. If you’re going to church, you go on Sunday just like everyone else. If you’re a low-income individual, you probably go shopping the day food stamps are delivered, just like everyone else. If you’ve still got a job, then the weekends are when you do your essential errands, just like everyone else. A spike in people going out on a given day probably produces a spike in new reported cases a week or two later. ---
**Author:** ![Kevbo](https://avatars.discourse-cdn.com/v4/letter/k/e47774/32.png) [@Kevbo](https://boards.straightdope.com/u/Kevbo)\ **Post date:** [May 5, 2020, 2:14am UTC](https://boards.straightdope.com/t/weekly-oscillation-of-new-daily-cases/853121/5 "2020-05-05T02:14:44Z")
Another possibility is medical staff or bureaucrats clearing their reporting backlog before the weekend. I can understand why keeping people alive would take priority over reporting deaths /infections. ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [May 5, 2020, 2:36am UTC](https://boards.straightdope.com/t/weekly-oscillation-of-new-daily-cases/853121/6 "2020-05-05T02:36:53Z")
Odd also that it started only in early April. It started the same time that they started adding in deaths that were suspected but not sure if that is related. ---
**Author:** ![RickJay](https://avatars.discourse-cdn.com/v4/letter/r/bb73d2/32.png) [@RickJay](https://boards.straightdope.com/u/RickJay)\ **Post date:** [May 5, 2020, 3:01am UTC](https://boards.straightdope.com/t/weekly-oscillation-of-new-daily-cases/853121/7 "2020-05-05T03:01:24Z")
I am pretty sure kanicbird is right. It’s a weekend thing that alters reporting times. The graph of cases in Canada dips every Sunday, like clockwork, then leaps back up on Monday.