COVID-19 FAQs
Lots of numbers get released about COVID-19 in New Hampshire. Which ones should I pay attention to?
The number of new cases each day, usually released by the Department of Health and Human Services around dinnertime, is the most obvious number to watch. Don’t worry about day-to-day fluctuations, however. The state combines results from half a dozen government and private labs for two types of tests, and their can be hiccups in reporting. Concentrate instead on the long-term average of new cases: The state gives a 7-day average while the Monitor lists a 14-day average because we think that gives a better sense of how the disease is progressing.
Note that the absolute average is less important than the relative average. In other words, it’s less important to know the average number of new cases right now than to know whether it has increased or decreased recently, and how quickly it is doing either of those. Change over time shows if the disease is spreading and whether you should start being more careful.
Another important number that’is the percentage of tests given each day that find an active case of COVID-19. This is known as the positive rate. When the positive rate rises above 5% that’s often taken as an indication that the disease is spreading quickly, to the point that the amount of testing needs to increase to measure the spread. The positive rate for New Hampshire had been below 5% since spring but as of late October it had risen higher.
Finally, check the number of hospitalization cases in the state, which shows if serious COVID-19 are increasing. The number of deaths, while tragic, is less good of an indicator about the spread of the disease because improvements in treatment protocols and testing can save lives even when COVID-19 is present.
What are the different types of tests?
There are two types of tests to detect active cases of COVID-19, called PCR tests and antigen tests, and one that indicates whether you have had the disease in the past, called the antibody test.
PCR stands for polymerase chain reaction, a process commonly used by biologists. It amplifies the amount of genetic material in the swab taken from people’s nose or throat and must be done in a laboratory. That is why it takes a day or two or more to get results from a PCR test.
The antigen test is a straightforward chemical analysis to detect certain proteins associated with the coronavirus that causes COVID-19. It can be performed on site in as little as 15 minutes, but is not as accurate as the PCR test. The antibody test detects antibodies, which are proteins created by the immune system as a response to a disease. If SARS-CoV2 antibodies are detected then the subject has been infected by the COVID-19 coronavirus and may still have the disease. This test is not always very accurate, however, because it takes time for the immune system to create antibodies and they are not always evenly distributed throughout the body and can be missed.
Do masks really work?
Yes, unquestionably. Research done over the summer by places like the Mayo Clinic find that the chance of inhaling an infected aerosol breathed by a nearby person is reduced by about two-thirds if you’re wearing a cloth mask over your nose and mouth. If both of you are wearing masks then the odds of infection fall by 90% or more.
Staying apart by six feet or more reduces the odds of infection further, for obvious reasons.
Make sure the mask covers not just your mouth but also your nose. You don’t want that coronavirus to get into your lungs by either route.
By David Brooks, Monitor staff