How Quickly Does Positive Lateral Flow Show. MonsterKidz Mon 13-Dec-21 160120. Usually a positive will show up long before the 25 minutes.
Usually a positive will show up long before the 25 minutes. His warning to families shows just how quickly a negative lateral flow test can turn positive. Symptoms typically start to appear five days after contracting Covid-19.
If you do not take the test within 48 hours you and the people you live.
But there is no specific time - they could have caught it yesterday and not become infectious until next week or it could happen sooner. They might be mild or moderate so its best to monitor them. It only took about five minutes to come up. It is probably worth doing more lateral flow tests in the days following to see if the result becomes stronger.
