[MUSIC PLAYING] SPEAKER: So now let's be very clear and define what we mean by case, contact, isolation, and quarantine. Those are important concepts that you'll have to really understand well throughout the rest of the course. So let's define what a case is and what a contact is. A case is someone who has COVID-19 or is infected with SARS coronavirus 2 and could infect others. Usually, this is defined by a positive laboratory test, usually a PCR test. And we've already discussed that. Sometimes, we may refer to cases that are suspect or probable cases, which means they may not have had a test yet, but we think they probably have the disease or the infection. So that could be someone that you know who was exposed to another infectious patient. So you think they probably have it, but they just haven't had their test yet. But sometimes, we refer to them as cases as well. A contact as someone who had exposure to a case when the case was infectious. Basically, this is someone who's been exposed to someone who was infectious. And we care about contacts because they could have been infected. And because of that, they need to take special precautions. If you'll recall, a case is infectious during their illness and the two days before their illness began. So you'll want to identify people who had some kind of contact with them during this infectious period. We talk about contacts. And there are really three different kinds of contacts that you should think about. The first is direct physical contact. So anyone that had a physical contact with someone who was infectious is at risk for infection. This includes things like shaking hands or hugging someone. If you've hugged someone during their infectious period, you're definitely a contact. We also talk about close contacts. And I want to define what a close contact means. This means someone who may not have had any physical contact at all, but was close to the person who is infectious. They were within six feet of this person, for example, for at least 15 minutes or more. Now, 15 minutes is just a guideline. In some places, they ask about close contacts who are nearby the case for 10 minutes or more or maybe even 30 minutes or more. So there's some flexibility there. You'll need to talk with your jurisdiction about where you're working to figure out exactly how they're defining these close contacts. But the basic idea is that you're nearby the person who's infectious for at least some period of time. And you're within six feet, which, if you'll recall, is the distance that many respiratory particles can travel. Finally, there's a third type of contact that you may also want to think about. And those are people who have been in the same room for an extended period, maybe an hour or more, with an infectious person, but they were more than six feet away. Some respiratory particles are smaller and can travel even farther than six feet, particularly when you're indoors, and there's poor ventilation. So sometimes, these people could also be at risk for infection because they've been breathing the same air for an extended period of time. These are called proximate contacts. And sometimes, you'll also be looking for these types of contacts when you're doing contact tracing. Now let's define what we mean by isolation versus quarantine. Both of these terms mean that someone is going to distance themselves from other people. Someone's going to stop having contact with other people in both isolation and quarantine. But they mean different things because they apply to different groups of people. So let's be clear about these. Isolation means keeping sick people or infectious people separate from others or from healthy people while they're infectious. This can be done within the home. So you could restrict yourself to your home as part of isolation. If you live with other people, you would also need to keep from having contact with other people within the home. If you're unable to do that within your home, then you may need to go somewhere else to isolate yourself from other people while you're infectious. In some places, people may go to a hotel or find another place to stay where they truly can be separate from others. In hospitals, patients will have to have a separate space and have very limited contact with anyone else except health care workers who are wearing the appropriate masks, gloves, and gowns to keep them safe. So how long should someone isolate from other people? Well, ideally it's for the duration of their infectious period. As we've already discussed, that will start two days before the onset of their illness. And it will last through the duration of their illness. Some people are sick longer than others. So their infectious period could be longer than others, too. But in general, we would say that someone can stop isolating themselves from others safely if it's been at least 10 days after the onset of their illness, and all their symptoms are improving, and their fever is gone. Quarantine means restricting the movement and contact of healthy people who've been exposed to someone who is infectious and could have been infected themselves. So we isolate a case when they're infectious, but we quarantine contacts because they've been exposed and could become infectious. Contacts should be quarantined for 10 days since the last contact they had with the infectious patient, the person who may have infected them. It's important to know when their contact was to be able to figure out how long they need to quarantine. [MUSIC PLAYING]
