Asymptomatic Carriers Represent 50% of ‘Driving Force’ Behind COVID-19 Transmission, New Study Says
Determining the actual number of asymptomatic COVID-19 cases has been a significant challenge for researchers and public health officials. The U.S. Centers for Disease Control and Prevention (CDC0 estimates that about 40 percent of coronavirus carriers are asymptomatic.
In a study out last month, CDC researchers found that 59 percent of all COVID-19 transmission came from asymptomatic people, defined by the CDC as those who are infectious before developing symptoms and individuals who never experience symptoms.
The latest study, however, indicates that asymptomatic cases might represent an even larger majority of COVID-19 infections. Researchers at the University of Chicago reviewed the initial COVID-19 outbreak in New York City. They found that just 13 percent to 18 percent of COVID-19 cases were symptomatic — between one in five and one in seven.
Moreover, the research team found that non-symptomatic cases “substantially contribute to community transmission, making up at least 50 percent of the driving force” of COVID-19 infections. That’s just slightly lower than the CDC study’s 59 percent estimate.
The researchers created a formula based on antibody tests taken in New York City from March to April, along with the city’s recorded cases from March to June. They also looked at New York’s testing capacity during that time. Their findings were published in the Proceedings of the National Academy of Sciences .
“Even if asymptomatic people aren’t transmitting the virus at high rates, they constitute something like 80 percent of all infections,” said co-author Qixin He, now an assistant professor at Purdue University. “This proportion is quite surprising. It’s crucial that everyone—including individuals who don’t show symptoms—adhere to public health guidelines, such as mask wearing and social distancing, and that mass testing is made easily accessible to all.”
The researchers say this is the first peer-reviewed model “to incorporate data about daily testing capacity and changes in testing rates over time to provide a more accurate picture of what proportion of COVID-19 infections are symptomatic in a large U.S. city.”
Vitamin C, Zinc Do Not Help Ease COVID-19 Symptoms, Study Concludes
Despite the popular use of vitamin C and zinc — despite little conclusive evidence — to help lessen the severity of viral colds and flu, new research finds that using the two supplements were of no benefit in reducing the severity of COVID-19 symptoms for those fighting the coronavirus at home.
A new randomized study, published in JAMA Network Open , concluded that vitamin C and zinc — individually or combined “did not significantly decrease the duration of symptoms compared with standard of care.”
The researchers halted the study early because there was no marked difference found between the four groups of COVID-19 patients that were asked to track their progress. The four groups included those getting standard care; those getting extra vitamin C; those getting extra zinc; those getting extra supplements of both.
“Given the widespread public use of supplements, such as zinc and ascorbic acid (vitamin c), for the prevention and treatment of viral infections, we applaud the COVID A to Z Study investigators for adding rigorous science by testing their efficacy and challenging popular beliefs,” Erin D. Michos, M.D., of the Johns Hopkins Ciccarone Center for the Prevention of Cardiovascular Disease, Johns Hopkins University School of Medicine, in an accompanying editorial to the study. “Unfortunately, these 2 supplements failed to live up to their hype.
Vitamin C is a recognized antioxidant, and plays an essential role in supporting the immune system as part of a healthy diet. However, using vitamin C after cold symptoms start does not appear to be helpful, according to the National Institutes of Health. Some studies have indicated that relatively large doses may reduce duration of cold symptoms, but you should always consult with your doctor regarding the use of any vitamin supplements, researchers say.
CDC: Do Not Take NSAID Pain Relievers Before COVID-19 Vaccination as Preventive Measure
The U.S. Centers for Disease Control and Prevention  (CDC) is urging everyone to avoid commonly available pain relievers before getting a COVID-19 vaccination. Some people take the pain reliever, called NSAIDs, or nonsteroidal anti-inflammatory drugs, in anticipation of discomfort or soreness from the injection.
However, researchers currently don’t have sufficient information on the impact of such meds on the COVID-19 vaccine’s antibody response. The CDC says that these pain relievers can be taken if a person feels any pain or discomfort after receiving the injection.
“Antipyretic or analgesic medications (e.g., acetaminophen, non-steroidal anti-inflammatory drugs) can be taken for the treatment of post-vaccination local or systemic symptoms, if medically appropriate,” the CDC states. “However, routine prophylactic administration of these medications for the purpose of preventing post-vaccination symptoms is not currently recommended, because information on the impact of such use on mRNA COVID-19 vaccine-induced antibody responses is not available at this time.”
In addition, the CDC also is urging people to avoid antihistamines prior to COVID-19 vaccination to prevent allergic reactions. “Antihistamines do not prevent anaphylaxis, and their use might mask cutaneous symptoms, which could lead to a delay in the diagnosis and management of anaphylaxis,” the CDC states.