Homes

You shouldn’t enter the home of someone who is sick

Many common illnesses, from diarrhea to colds, can be spread inside the house of someone sick. Some of these illnesses are spread either by direct contact with secretions (the gross stuff—snot, phlegm, spit, poop) or by breathing in tiny drops of secretions that have been sneezed or coughed into the air. If a person is sick with a viral or bacterial infection that is spread by their secretions, and if you touch something in the house that has those secretions on it, then you might get sick. For example, doorknobs, dirty tissues, or toys that a sick baby has slobbered on could be contaminated and may pass on infections if you touch those things and then put your hands in your mouth. While germs could be aerosolized or present in the air in tiny liquid droplets, this is more of a risk if you are very close to the infected person. However, as the chapter on breathing the same air as a sick person suggests, it is possible for you to catch a bug from the air in the same house as a sick person. The air within residential houses is typically exchanged for outside air less frequently than the air in office buildings. Although this could allow the germs to hang around in the air, you should remember that the average house has far fewer people potentially sending their germs into that air than the average office building.

So, there is a risk, but it is not a huge risk. Many of these germs, whether bacteria or viruses, do not live for very long once they are outside the body. And for many of them, the greatest risk is when you are very close to the sick person, or when the sick person’s secretions are freshly coughed or sneezed or slobbered onto things. You have to get a certain number of the germs into your body before they have a good chance at making you sick. Even if you touch or breathe in something contaminated, there may not be enough living germs on that thing to make you sick.

Some of the viruses that cause diarrhea, such as rotavirus, are among the most difficult to escape in a house. In studies, rotaviruses have been able to survive for days to weeks on surfaces around the house, and ingestion of as few as ten rotavirus particles can cause infection. If someone in the house has rotavirus, you should probably try to stay away!

Despite the possibility of getting infected, it is important to remember the big picture. Not all infections are spread through the air or through secretions or body fluids; some would require you to directly touch the infected area on the person. And, of course, some illnesses are not contagious at all. Furthermore, even for infections that are spread through the air or through contact with infected secretions, you still may not get infected even if you are in the same house.

How can you escape infection? First of all, good hand-washing (and not sucking on your fingers or picking your nose with dirty hands) can help you to avoid getting infected from even the most infected secretions that may be around the house. Second, a quick visit is unlikely to hurt you. In a study where sick volunteers spent time living in small quarters with healthy volunteers, it took a long time before anyone passed on infections. Even though the sick people and the volunteers were playing board, card, and video games in close contact with each other throughout the study, it took an average of 200 hours of exposure to the sick people in order for the healthy volunteers to get infected themselves. It is also important to remember that the risk of getting infected in public places with a lot of people is higher than the risk you face with a limited number of people over a short time. Going into a house with one or two sick people may be less of a risk than being on a subway or bus with a whole bunch of people.

Beyond hand-washing, the Centers for Disease Control and Prevention offers some suggestions for further decreasing the risk of spreading illnesses like influenza within the house. The CDC suggests that linens, dishes, and utensils used by those who are sick do not need to be cleaned separately, but they do caution against sharing these items unless they have been washed first. The CDC even gives laundry advice; they recommend washing towels and bedsheets with regular laundry soap and tumbling them dry on a hot setting. They also suggest that you should not hold laundry against your body and that you should wash your hands after you handle dirty laundry. It is considered safe to wash the sick person’s eating utensils in either a dishwasher or by hand with water and soap.

You should also know that people are generally contagious before they have any symptoms from their infections—before they even know they are sick. This seems like a depressing piece of news, but we would argue that you never really know when someone might be getting sick, and so the practical thing is to avoid wasting time being concerned about who may or may not infect you. Instead, practice the basic precautions to avoid infections or illness. Wash your hands!