[spikels]

Nine months into this it would be nice if we had good data on the risk factors of transmission. I know it’s a tricky virus to trace but shouldn’t we have better info on which activities demographics, etc are the most risky by now?

[jeffbee]

We do know the risk factors. It's a respiratory disease that spreads when people who are breathing are near each other. We don't need a random control trial to tell us that practicing with your brass band can spread it. The solution is to stay very far from everyone until the disease is wiped out. Only very intelligent libertarian contrary Americans think we don't have the information we need.

[s1artibartfast]

That is not very helpful advice when you have to manage risk while trying to eat, work, live, and stay healthy. Stats certainly exist on where some of the 16,000+ cases in San Mateo were transmitted.

[jeffbee]

Exactly what information do you lack? If you are hungry eat at home. Work at home if possible. Exercise at home. "Live" is too vague to address.

[s1artibartfast]

You are substituting instructions for information. I lack information. For example:

Has anyone in San Mateo caught covid eating at a restaurant? How many?

Has anyone in San Mateo caught covid grocery shopping? How Many?

Has anyone in San Mateo Caught covid exercising outside? How many?

Has anyone in San Mateo Caught covid at school? How many?

[monodeldiablo]

There's no way to get the information you desire without Big Brother level tracing. And even then the error bars are huge. Symptoms set in days after exposure, and transmission is uneven at best.

Full disclosure: I've had covid.

We assume we were exposed at the clinic, where our kid needed emergency medical treatment. But if so, only one of us was with the child indoors -- in a cleaned room with a doctor in full PPE and us in masks -- and treatment lasted less than 5 minutes.

But by the time we experienced onset of symptoms, days later, we had been in close proximity with my in-laws (they need care and were part of our bubble) for over 24 hours. Luckily, they developed no symptoms and tested negative.

So 5 minutes of exposure to an asymptomatic carrier at the clinic likely transmitted the virus to us, but 24 hours in close contact failed to transmit the virus to my in-laws.

The delay of onset and inconsistent transmission patterns make this virus exceedingly difficult and expensive to track. Your questions are unanswerable.

[s1artibartfast]

>There's no way to get the information you desire without Big Brother level tracing.

As I responded to the sibling comment, I don't think that is accurate. Of course many, if not most cases can not be traced, many certainly can be. Some people know exactly where they got covid, and who they exposed, and where.

The US has 50,000 full time contact tracers working to collect this information. Surely there is some data by now?

>Your questions are unanswerable.

IF the question is categorically unanswerable (which I don't believe), contact tracing programs should be disbanded.

[s1artibartfast]

Here are some examples of data supporting the unanswerable questions, complete with business addresses with known case count.

http://publichealth.lacounty.gov/media/coronavirus/data/cont...

http://publichealth.lacounty.gov/media/coronavirus/locations...

[baskire]

They just don’t have the data.

Look I got covid while wearing a mask. Infection was either at a grocery store. Or while walking at a park. Or while at a dog park. Or who knows.

How do you log that in your stats?

[s1artibartfast]

You log it as "unknown community transmission". While you obviously can't trace everyone, California has 10,000 contact tracing staff [1] and has spent most of the pandemic with less than 5,000 confirmed cases per day [2]. These individuals are working every day to collect data, so I am sure it exists.

If you get a positive test, contact tracers may ask you where you went and who you interacted with. They then call those people and ask them to get a covid test. IF the contact tests positive, then rinse and repeat. [3]

If I live alone and only leave my house to grocery shop, it is pretty clear where I got covid. Similarly, if Bob had covid, I had dinner with Bob, and now I have covid, it is pretty safe to assume I got at dinner.

Anecdotally, I had a friend who tested positive and the contact tracer told them that they had likely contracted while it shopping at a big 5 several days earlier.

https://coronavirus.jhu.edu/contact-tracing/state-survey-res...

https://91-divoc.com/pages/covid-visualization/states.html

https://covid19.ca.gov/contact-tracing/

[nradov]

The virus is now endemic in the worldwide human population, plus some animal reservoirs. Even with widespread vaccination it will never be wiped out.