I found it interesting in the Kilmore coronavirus cases the government is now trialling 14 day isolation of contacts of contacts of coronavirus cases. At first I thought this is a good thing, but again it appears, to me at least, the government has missed the mark.
https://www.abc.net.au/news/2020-10-07/coronavirus-outbreak-kilmore-fears-more-restrictions/12736860
If someone gets infected it makes sense the close contacts isolate for 14 days. By makes sense, you still have to wonder if 14 days is really the appropriate length of time. For example people are tested after 11 days and then their isolation is over after 14 days. So why not 12 days if it now supposedly takes a day to get the test result back. I still haven't found conclusive scientific studies to indicate after how many days a coronavirus test can identify a person is infected. Early on the figure was 95% certainty after 5 days. More recently the median was reported as 8 days. Reportedly there's around 97% certainty after 14 days and if that's true, that still means 3 cases per 100 could be positive. I have a feeling this information is probably available somewhere.
Back to the point. I think it is very good that contacts of contacts are now asked to isolate. This should have been done months ago. But once the contact of the positive case is shown to be negative, then really should the contacts of the contacts still be isolated? What is the probability of the contact of the case developing coronavirus once they've tested negative? Then what is the probably of the contact of a contact that has initially tested negative becoming positive. I can only guess the probably would have to be very low.
To have contacts of contacts isolate for 14 days once the initial contact has test negative and results are known, should probably mean all their contacts no longer need to isolate.
I do feel the government has made progress by asking contacts of contacts to isolate (taken far too long to get to that point), but it does make sense for contacts of contacts to isolate until the result for the initial positive case contact is known. From earlier media reports contacts of contacts did not have to isolate at all, which I don't think was a good approach.
No matter what the government does, what you do is your choice. For us if someone we know needs to get tested, if we know one of their contacts, we won't go near that contact until we know the result of for the person they've been in contact with.
If the test was positive and we'd been in contact with their cases contact, we'd isolate until the contact was tested and their results were back as negative. If the result of the contact was positive we'd isolate for 14 days and also get tested. We would let anyone we knew that had been in contact with us we'd been in contact with a positive case, so they could isolate immediately and wait until we received our test result.
There are many things which makes it harder and one thing is false negatives. That means people think they've not infected when they actually are infected. Luckily percentage wise this is relatively low.
The rough timeline that I think is important to consider is:
1. Person is known to have coronavirus and is thus positive.
2. The person may have taken 2-3 days before symptoms appeared, or not symptoms may have appeared at all. It is important to take into account contact with a person before they were known to be positive. Also it takes 1-2 days to get test results back. People may also wait a day or two after they get initial symptoms before they get tested. Overall this could mean 5-7 days for a person that is positive since they were infected.
3. Contacts of a positive person should probably to wait 2-3 days before being tested to ensure they would have a sufficient viral load to provide a reliable result.
4. Contacts of contacts then also need to wait 2-3 days before being tested to see if they are infect. It's here there's a problem because typically contacts of contacts, if I'm correct, have typically not been able to get tested. This is where we have a hole in our approach to containing coronavirus. I suspect the best we can hope for is if we are a contact of a contact, then if the contact of the positive case gets a negative result, there's a very high probability the contact of a contact would also be negative.
Based on the above it would then probably be wise for contacts of contacts to isolate for at least 3 days, but preferably up to 5 days as this is when symptoms, if they are to show, will have shown.
In summary, the important period for a positive case is the period of up to 7 days before they are known to be positive. If you've been a close contact during this period then you should isolate for 14 days. As a contact of a contact if the contact is negative then it would be prudent to isolate for 3-5 days, but if they are positive then you become the close contact of a positive cases and should then isolate for 14 days. The missing component from the government's coronavirus control strategy has been contacts of contacts. Since it is missing, then it is up to ourselves as contacts of contacts to do what we feel is right in the interests of everyone..
Finally, one thing I noticed in some articles for Kilmore were pictures with long queues of people waiting to be tested. Yes they were wearing masks, yes they were social distancing, yes they were outside, but the type of masks only reduce the risk by half and when you have a large number of people together for an extended period of time, the risk of infection increases. If possible opt for being tested using a drive through facility, Whilst there's no proof of anyone being infected waiting for tests, there's been thousands of Victorians infect where they don't know the source. Best to be as safe as possible.
Kelvin Eldridge
www.Mapz.com.au/coronavirusvictoria/
