What exactly is the human hemipulmonary virus that has become a hot topic, and how can we deal with it?

Recently, the topic #国产发生人体块病毒菌# suddenly became a hot search topic. The topic content shows that according to the respiratory virus monitoring of the Centers for Disease Control and Prevention (CDC), human metapneumovirus (hMPV) has shown a high incidence in various regions of the United States this spring, which has aroused concern.

At the peak of infection in mid-March, the PCR test positivity rate was 11%, and the antigen test positivity rate was 18%, both values ​​exceeding those before the COVID-19 pandemic (the HMPV infection rate did not exceed 7.7% in the four years before the COVID-19 pandemic). Currently, HMPV infection has also begun to occur in China.

The introduction that "there is no vaccine for human metapneumovirus, and there is a lack of specific antiviral drugs, and the infection rate is highest in infants under 1 year old" made many netizens tremble with fear, and they left messages one after another:

“A new virus?”

“Without a vaccine and without medicine, isn’t that terrible?”

"Are infants really susceptible? What symptoms will they have? How can we prevent it?"

Stay calm!

Human metapneumovirus is not actually a new virus

"Human metapneumovirus is not a new virus. As early as 2001, Dutch scholars first reported its discovery. It has a history of causing respiratory infections for at least 60 years and exists all over the world. In recent years, with the advancement of medical standards and improvements in virus detection methods, the detection rate of clinical human metapneumovirus has increased significantly." said Hua Wang, chief physician of the Department of Infection at Zhejiang University Children's Hospital.

So what is human metapneumovirus? Human metapneumovirus belongs to the same family as respiratory syncytial virus, the Pneumoviridae. It is an enveloped single-stranded negative-sense RNA virus with a total of four subgenotypes (A1, A2, B1, B2).

Human metapneumovirus infection is ubiquitous and seasonal. Transmission is most active in late winter and spring in temperate regions. During the peak respiratory disease season, human metapneumovirus, respiratory syncytial virus, and influenza can circulate simultaneously.

Children are susceptible

But the symptoms are generally mild

Self-limiting

Human metapneumovirus can cause upper and lower respiratory tract infections in people of all ages, but symptomatic infections mostly occur in young children, the elderly, and people with weak immune systems. A 13-year study in nine provinces in my country showed that children under the age of five were the main group of people infected with human metapneumovirus, with a detection rate of 3.71%. The positive rate of human metapneumovirus detection at Zhejiang University Children's Hospital in the past two years was 1.5%-4.4%.

However, parents do not need to worry too much. The common symptoms of infection in the general population are relatively mild, and may include coughing, fever, nasal congestion and shortness of breath, which are similar to the symptoms of common respiratory diseases. The incubation period is 3 to 6 days, and most symptoms disappear within 1-2 weeks. Some people may also experience severe symptoms such as bronchiolitis, asthma attacks, severe pneumonia, encephalitis, and acute respiratory distress syndrome, but the overall situation is less.

At present, what parents are most anxious about is that there is no specific antiviral drug for the virus, nor a vaccine to prevent the virus. So how should children prevent it, and what should they do once they are infected?

Chief Physician Hua Wang said: "Human metapneumovirus infection is similar to respiratory infections caused by other viruses, with mild symptoms and self-limiting. Simply put, the body's immune system can completely eliminate the virus after a period of time, so that the disease will automatically stop after it develops to a certain extent and gradually heal without causing chronic damage, so parents do not need to worry too much."

How to prevent it?

Experts: Wear a mask and wash your hands frequently

Stay away from virus infection sources

In addition, Chief Physician Hua Wang reminded: Human metapneumovirus is mainly transmitted through human-to-human contact. The most common transmission routes are droplet transmission and contact transmission. Coughing, sneezing, limb touch, shaking hands, touching objects or surfaces with the virus and then touching the eyes, mouth and nose, etc., may lead to infection.

Therefore, washing hands frequently and ensuring that the soap remains on your hands for more than 20 seconds; avoiding touching your eyes, mouth, and nose with unwashed hands; and avoiding close contact with sick people can effectively prevent infection. It is worth noting that human metapneumovirus is not transmitted through small particle aerosols. Therefore, keeping a distance of ≥2 meters from the source of infection can reduce and block its aerosol transmission.

For children who have already developed fever and respiratory symptoms, they should pay attention to coughing etiquette, wear medical surgical masks, and prevent the spread of the virus; they should go to the fever clinic in a timely manner. Those with obvious fever and respiratory symptoms are advised to rest at home and manage the source of infection.

At present, the Laboratory Department of Zhejiang University Children's Hospital has launched 13 respiratory pathogen detection projects, including common clinical respiratory viruses such as human metapneumovirus. The results can usually be obtained on the second day of the examination.

Metropolis Express·Chengshi Interactive reporter Wu Shuang Correspondent: Zhu Yaoling