[MUSIC PLAYING] SPEAKER: As a contact tracer, you'll need to be able to calculate how long a case should isolate and how long a contact should quarantine themselves. It'll be based on your understanding of their infectious period. And it will be an important component of working with cases and contacts to limit the spread of disease. So let's go through some examples, some very practical examples using a calendar to see how this might work. How long should a case be isolated from others? Well, the short answer is ideally as long as they are infectious, but there is a longer answer. We know that by the time they're diagnosed, they may already be sick. So by the time you're investigating this case, their infection period has already started probably at least a few days before. So you'll need to talk to them about isolating themselves for the remainder of their infectious period. They'll have to monitor their symptoms each day to help you determine if they're still infectious. And recall that if it's been at least 10 days after their symptom onset, all their symptoms are improving, and they no longer have a fever, then they're able to end their isolation. Let's see practically what this will look like. So let's assume that you identify a case and you call them on May 10 you can see that here in the calendar. During the conversation with them, they tell you that they became ill on May 9. So now you know that they were infectious for two days before they became ill. And they'll be infectious for at least 10 days after their onset. You can see that here highlighted in blue. So that means May 9 plus 10 days equals May 19. So you can see here in blue their total infectious period, which started two days before their onset of disease and went all the way through May 19, which is 10 days after onset. So we know that the case will be infectious at least through May 19 in this example. But you'll need to have continuing follow-up to see when they can stop isolating from others because you'll need to know when their symptoms resolve without the use of medication. So the 19th is the earliest time they can stop isolating but just a reminder that you'll need to be following up with them to see if they can really stop isolating on the 19th or not. All right, so on this slide, the days of their infectious period are still shown in blue. We assume that we call the case on May 10. And you're going to ask them about the contacts they had since May 7, right? Because this is their infectious period. Those are shown here in yellow. We assume that after you call them, so from May 10 through May 19 or beyond, they're isolating themselves. So they're not going to have any additional contacts. So in your discussion with them on May 10, you'll need to list out everybody they had contact with since May 7. Then you'll go on to find those contacts and notify them and ask them to quarantine. And now that you've identified the contacts, you'll have to help them calculate how long they should quarantine. So how long should a contact stay in quarantine or distance themselves from others? The short answer is ideally as long as they could become infectious. Because we know that the majority of people who are infected will develop illness within 10 days of their exposure, contacts are asked to quarantine this long to be assured that they weren't infected. However, by the time that you're having a conversation with the contact, their contact with the case may have been days ago. So you'll need to figure out how much time they should quarantine from the time you talk to them. And in other examples, the contact may be ongoing. So for example, if they live with the case, then they lived with someone who's infectious. And sometimes, a case can't truly isolate at home unless they have their own room, their own bedroom, and they're receiving meals at the door. But in some cases, that's not possible either because there isn't enough space in the home or because the case needs care from another household member. So in that instance, the duration of quarantine will require some additional calculations. It's important to note that when you're having a conversation with a contact, if they've already developed symptoms, they should probably be considered a case. They should be tested. And you should talk to them about isolating rather than quarantine. Now let's think through a specific example. Remember the case we already talked about? Well, let's assume that you're going to call one of their contacts. And you're able to have a conversation with this contact on May 13. And on the call with this contact, you understand that their last interaction, their last contact with the case, was on May 10. If you'll recall, that's the second day of illness for the case. So they should receive instructions to quarantine for 10 days since their last exposure to the case. If their last exposure was on May 10, you would add 10 days. So that would mean that they should quarantine through May 20. We already mentioned that if a contact lives with a case and has ongoing contact with them, then figuring out their quarantine period could be a bit more difficult because their quarantine period is going to be longer. So the contact should quarantine themselves immediately and then also for 10 days following recovery of the case because that would be the last time they had contact with an infectious case. So for some contacts, quarantine is going to be longer than 10 days. Let's see what that would look like on a calendar. So let's assume the same scenario. We call the contact on the 13th of May. And it's the same case, but this contact lives with the case this time and has ongoing contact with them throughout their illness. So the person that they live with became ill on the 9th. This is the case we talked about before. Let's also assume that the case will be fully recovered by May 19. This would be 10 days since their onset of illness. Therefore, if the contact has to quarantine themselves for 10 days after their last infectious contact, then they would need to quarantine through May 29 because that would be 10 days after the full recovery of the case that they lived with. So you can see in this example where the contact lives with the case, their quarantine period is going to be 2 and 1/2 weeks long because they'll have to quarantine themselves while they're still having contact with the case and for 10 days after. [MUSIC PLAYING]