So far, the nasopharyngeal PCR test has been the gold standard for COVID-19 testing. This test, which uses a sample taken from a swab inserted through the nose toward the back of the throat, has a sensitivity of up to 95% in people who have symptoms. That is to say, the PCR test has the ability to correctly identify individuals who are positive for the virus that causes COVID-19. Just as important, unlike other tests, this test is not prone to the problem of showing that an uninfected person has COVID-19 (false positive). The test can, however, mistakenly show that an infected person does NOT have COVID-19 (false negative). Factors that can lead to a false negative are the stage of the infection and the technique used by the person obtaining the sample. PCR tests using samples collected in other ways (from the nostril or saliva) have shown encouraging results in people who are showing symptoms.
Anterior nasal swabs based on PCR methods also perform well in symptomatic individuals. More recently, PCR-based saliva testing has been shown to have high sensitivity in symptomatic people. The other main type of COVID-19 test uses what are called antigen
-based methods to determine whether a person is infected. This test also uses samples taken from the nose or saliva, but it does not need to be administered by a doctor, nurse, or medical technician; it can be performed at home. The tradeoff for this convenience is that antigen
-based tests are not as sensitive as the PCR tests.
Go to COVIDtests.gov
to order free testing kits. Every home is eligible to order two sets of four at-home tests.
There are still questions about how long immunity lasts—and how strong the immunity is—in a person who has been infected with and recovered from the virus that causes COVID-19. We know that the levels of antibodies that are formed after coronavirus infection decrease after 3-4 months. There have been documented cases of people who have been re-infected.
Wearing a mask prevents the spread of the respiratory droplets that can transmit the coronavirus that causes COVID-19 from one person to another. For this simple reason, mask-wearing is a helpful—and essential—strategy for protecting ourselves (and each other) from this infection.
The virus that causes COVID-19 continues to be present, at different levels in different areas, throughout the United States. Likewise, the rate of spread of the virus is variable across different regions and continues to change.
It is recommended that myeloma patients continue to practice caution (face coverings, good hand hygiene, and social distancing).
Staying aware of local COVID-19 trends—by checking the latest announcements from the WHO (here
) and the CDC (here
) —can help guide decisions on whether it is reasonably safe to take part in activities outside of the home.