What is the difference between a new coronavirus and a flu virus?

BEIJING, Feb. 21 (Xinhua) — In recent weeks, the outbreak of new coronavirus pneumonia, while another virus disease in the world, that is, influenza. What is the difference between the new coronavirus and the influenza virus? Which is more worrying? So far, pneumonia caused by the new coronavirus, which the World Health Organization (WHO) calls covid-19, has sickened more than 75,000 people and killed more than 2,000, but that’s not worth mentioning compared to the flu.

What is the difference between a new coronavirus and a flu virus?

Coronary virus is spherical or elliptical, with a regular arrangement of cystic collagen fibroblasts, shaped like a crown, and therefore named.


Still, scientists have been studying seasonal flu for decades. So while influenza viruses are dangerous, we already know a lot about them and what happens every epidemic season. By contrast, few people are aware of the 2019 new coronavirus (which the International Committee on Virological Classification named SARS-CoV-2, but stressed that the name is not associated with SARS disease) because it is too new. This means that the scope and number of deaths of the virus is unknown.

“Despite the high incidence and mortality rates of influenza, seasonal influenza is certain,” Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said at a White House news conference on January 31. I can tell you for sure that as we move into March and April, flu cases will drop. You can predict the range of mortality and hospitalization with considerable accuracy. The problem now (of the new coronavirus) is that there are many unknowns. “

Scientists are trying to find more information about the new coronavirus, and with the advent of new information, our understanding of the virus and its dangers may change. Based on what we know so far (19 February), we have compared the new coronavirus with the influenza virus.

Symptoms and severity

Seasonal influenza viruses (including influenza A and B) and 2019 new coronaviruses are infectious viruses that cause respiratory diseases. According to the U.S. Centers for Disease Control and Prevention, typical flu symptoms include fever, cough, sore throat, muscle soreness, headache, runny nose (or nasal congestion), fatigue, and sometimes vomiting and diarrhea. Flu symptoms often pop up. Most people with the flu will recover within two weeks. But for some people, the flu can cause complications, including pneumonia. So far, about 1 percent of Americans have had symptoms of enough hospitalization so far this flu season, similar to the rate of the previous flu season, according to the Centers for Disease Control and Prevention.

For the new coronavirus of 2019, doctors are still trying to understand the full picture of the symptoms and severity of the disease. A small study of about 100 people infected, published in the January 30 issue of the Lancet, showed that the most common symptoms were fever, cough and shortness of breath. In the study, about 5 percent of patients reported sore throats and runny noses, and only 1 to 2 percent reported diarrhea, nausea and vomiting.

In a recent study, researchers at the Chinese Center for Disease Control and Prevention analyzed 44,672 confirmed cases in China between December 31, 2009 and February 11, 2020. Of these cases, 80.9 per cent (36,160 cases) were considered mild, 13.8 per cent (6168 cases) were moderate and 4.7 per cent (2087 cases) were severe. “Severe cases are those in patients who exhibit respiratory failure, infectious shock, and/or multi-organ dysfunction/failure,” the researchers wrote in a paper published in the China Center for Disease Control and Prevention.” “

It is important to note that, according to WHO, it is difficult to distinguish between respiratory viruses based solely on the basis of symptoms, as they can cause similar symptoms.


So far, about 0.05 percent of those infected have died in the current flu season in the United States, according to the Centers for Disease Control and Prevention. By contrast, the mortality rate for the new coronavirus in 2019 appears to be higher than that of influenza.

In a study published February 18 in the Journal of the Chinese Center for Disease Control and Prevention, researchers found that the death rate for new coronavirus pneumonia among adolescents under 19 years of age in mainland China was about 2.3%. This is much higher than the death rate from influenza. According to the New York Times, the flu mortality rate in the United States is typically around 0.1%.

Nevertheless, the mortality rate of neo-coronavirus pneumonia varies depending on factors such as location and age. In Hubei province, for example, the mortality rate was 2.9 per cent, while in other provinces it was only 0.4 per cent. In addition, the mortality rate among the elderly is highest among different populations. The mortality rate was 14.8 per cent for people aged 80 and over; in the 70-79 age group, the mortality rate for neo-coronavirus pneumonia was about 8 per cent; for those aged 60 to 69 it was 3.6 per cent; for those aged 50 to 59, for those aged 50 to 59, for the age of 40 to 49, for the population of 0.4 per cent; and for those aged 10 to 39, it was only 0.2 per cent. So far, no children under the age of 9 have died from the coronavirus.

Virus spread

Scientists often use “basic infections” (R0, read R-nit) to determine how easy it is for the virus to spread. Epidemiologically, this refers to the average number of people who have contracted an infectious disease and how many others are infected without external intervention and no one is immune. The higher the R0 number, the harder it is to control an epidemic. According to the New York Times, the R0 value for influenza is about 1.3.

Researchers are still trying to determine R0 for the new coronavirus. A study published January 29 in the New England Journal of Medicine (NEJM) estimated that the r0 value of the virus was 2.2, which means that an average of 2.2 people per infected person were transmitted. It is important to note that R0 is not necessarily fixed. Previous reports have said estimates vary from location to location, depending on how often people come into contact with each other and efforts to reduce the spread of the virus.

In addition, the incubation period of influenza viruses and new coronaviruses is different, with the former being more complex than one to four days. According to a retrospective study by Zhong Nanshan academician, the median incubation period of the new coronavirus is 3 days, but the difference between different patients is obvious, some of the fastest day of onset, and one patient claims to have developed symptoms after a 24-day incubation period. The length of the incubation period of the virus is an important factor affecting the ability of the disease to spread, and the longer incubation period poses a challenge to early diagnosis and isolation.

Risk of infection

The U.S. Centers for Disease Control and Prevention estimates that on average, about 8 percent of Americans get the flu each flu season. There are currently 29 cases of new coronavirus pneumonia infection in the United States, according to the U.S. Centers for Disease Control and Prevention. The agency also said it was unclear how the situation would develop in the U.S., where some people, including health care workers, are at increased risk of exposure to the new coronavirus, but the immediate health risks posed by the virus are currently low for the U.S. public.

It should be noted that although influenza is known as influenza, it is far from the common cold. Influenza is caused by a special type of influenza virus, the symptoms can be light and heavy, compared to the common cold, the cause of influenza is different, more infectious and higher fatality. The world’s annual flu season causes about 3 million to 5 million serious illnesses, of which about 250,000 to 500,000 die.


It is worth noting that seasonal influenza viruses that erupt each year should not be confused with a new strain of influenza virus that has erupted globally. The U.S. Centers for Disease Control and Prevention estimates that between 151,000 and 575,000 people died from swine flu worldwide during the 2009 swine flu pandemic. Pandemic refers to the rapid spread of a disease, involving a wide geographical area, a large proportion of the population, can be in a short period of time across provincial boundaries, national boundaries and even continental boundaries to form a worldwide epidemic. Seasonal influenza is significantly different in severity from a new influenza pandemic, so there is no current influenza pandemic.

Since most cases of new coronavirus pneumonia occur in China and there is no outbreak in other countries or regions, the outbreak has not been assessed as a pandemic. On January 30th the World Health Organization declared the outbreak of new coronavirus pneumonia a “public health emergency of international concern”, a statement focused on concerns that the virus could spread to countries with weak health systems.


Seasonal influenza has a vaccine to prevent infection, but there is currently no vaccine for the new coronavirus of 2019. Scientists and doctors are working on a potential vaccine, hoping to launch clinical trials in the coming months.

In general, for the spread of respiratory viruses, including coronaviruses and influenza viruses, the CDC recommends several precautions: wash hands regularly with soap and water for at least 20 seconds; cleaning and disinfecting objects and surfaces that are frequently in contact with.