Coughing, wheezing, difficulty breathing... Note! The virus began to circulate out of season

*For medical professionals only

The detection rate of respiratory syncytial virus is on the rise

Written by | Li Yuelan

Respiratory syncytial virus (RSV) is one of the most familiar pathogens to primary pediatricians, especially in the northern regions. Every winter and early spring, a large number of infants and young children have symptoms such as cough and wheezing, and the wards are full, and it is difficult to find a bed.

Every night shift is on duty, after the wee hours of the morning, I have to go to the ward to deal with children who are too short to be quiet, and the children in the ward have their voices like "bellows", gasping and coughing... So much so that a few years ago, every winter, because of the epidemic of syncytial virus, the shortage of pediatricians would become a social topic.

However, no one expected that from last winter to the beginning of spring this year, there would be very few RSV infections. Paediatric wards have seen a large number of empty beds during what should have been a busy season. While everyone is rejoicing, they are also full of doubts, is this virus so gone?

In fact, we can never underestimate the presence of a virus.

Just 1 week ago, the outpatient clinic received a 35-day-old baby with a cough for 3 days and an aggravation for 1 day. Opening the quilt, the child did head little by little, shoulders also followed one end to another, the nose flared, a small wheezing sound came out of the throat, the wheezing was more obvious after activity, and the dense stridor of the lungs was auscultated.

The child is a typical bronchiolitis and admitted to the pediatric ward. After 3 days of hospitalization, cough, wheezing worsened, dyspnea, obvious three-pitting signs, blood gas analysis showed respiratory failure, and non-invasive ventilator was used to assist breathing and other symptomatic treatment, and the child's condition gradually stabilized.

After this child, several small babies were admitted one after another, including newborns, with similar symptoms and signs, early only symptoms of upper respiratory tract infection, and soon wheezing, in line with the clinical manifestations of bronchiolitis, stumped RSV in the summer and anti-season epidemic?

On May 11, Baoding Hospital, Beijing Children's Hospital affiliated to Capital Medical University, released a pathogenology briefing: the detection rate of RSV is on the rise.

On May 15, the public account of Hebei Daily published an article mentioning that many parents in Shanghai have recently been "scared" by another virus, which is RSV. On social media, many parents shared the process of their children's recent infection with RSV, lamenting that the virus is menacing, even more unsettling than the new crown and influenza.

What exactly is RSV? Is bronchiolitis severe after infection?

Bronchiolitis is a unique respiratory infectious disease of infants under 2 years old, with wheezing, shortness of breath and three concave signs as the main clinical manifestations, also known as wheezing pneumonia in China. More than 50% of the cases of this disease are caused by RSV, and bronchiolitis caused by RSV is more common in winter and early spring in northern China, and summer and autumn in Guangdong and Guangxi.

The disease only occurs in infants under 2 years old, most of them are about 6 months old, and small infants under 2 months often have more severe symptoms and are prone to complications. Children often have persistent dry cough and episodic wheezing 2 to 3 days after upper sensation. The simultaneous occurrence of cough and asthma is characteristic of the disease. Symptoms range in severity and range from no fever or low-grade to moderate fever.

Physical examination is marked by a tympanic sound on chest percussion, often accompanied by prolonged expiratory breath sounds and expiratory stridor. Rapid breathing with nasal flapping and tridentation. Children with severe disease are pale or cyanosis. When the bronchioles are close to complete obstruction, breath sounds are markedly reduced. Crackles are often not heard when wheezing is severe; When wheezing relieves slightly, diffuse medium and fine crackles may be heard. Severe cases can develop heart failure and respiratory failure.

Neonatal RSV infection can cause interstitial and bronchiolitis, which predisposes to overcrowded, premature, and low birth weight infants. Secondary RSV infections in hospitals are as high as 30% to 50%. The disease is often severe, with apnea and BPD developing. Children often have wheezing, coughing, no fever, and wheezing, sometimes crackles, on auscultation of the lungs.

X-rays show scattered small patches and hyperinflation of both lungs and cord opacities, emphysema. Tracheal secretions and nasopharyngeal washes can be isolated to syncytial virus, enzyme-linked immunosorbent assay, serum specific IgM antibodies, can be used as sensitive, specific, rapid diagnosis. RSV can cause neonatal unit epidemics, and patients must be isolated.

The most dangerous period of the disease is 48-72 hours after the onset, and the case fatality rate is 1%. The course of the disease is generally 5-15 days, with an average of 10 days.

So why is syncytial virus infection, which should have occurred in winter and spring, epidemic out of season?

Hebei Daily public account analyzed: the cause of this anomaly may be related to self-protection during the epidemic, through wearing masks, home isolation and frequent hand washing and disinfection and other measures, cut off the transmission route of RSV, reduce the infection rate of RSV, and because of the stimulation of contact with pathogens is reduced, children's immunity to the virus is also generally reduced, and with the effective control of the domestic epidemic, the change of prevention and control policies, the scope of public activities expands, people gather, resulting in an increase in RSV infection, resulting in an out-of-season epidemic.

RSV can cause endemic endemic through close contact with coughs or sneezes in patients and exposure of the nasopharyngeal mucosa or ocular mucosa to virus-containing secretions or contaminants.

What to do after an infection and when do I need medical attention?

Most symptoms of children with RSV infection will disappear on their own within 1-2 weeks, there are currently no antiviral drugs, and current treatment is mainly aimed at relieving symptoms, mainly with supportive care and rehydration and respiratory support if necessary.