Alert! This Virus Is Spreading Fast! Keep These Prevention Tips Handy.

Indeed, the surveillance data for acute respiratory infectious diseases released by the Chinese Center for Disease Control and Prevention (China CDC) shows that the positive rate of influenza virus testing has been rapidly increasing. In both southern and northern regions, it has risen to the top of the positive rate of outpatient respiratory sample testing in the 49th week of 2024 (December 2-8), and the surveillance data for the following 50th week shows that the positive rate of influenza virus testing continues to rise rapidly.

Many parents who have read about the flu may have a feeling:

The flu is very common, happening every year, and even consider it as just a bad cold.

This understanding is actually wrong. As the saying goes, “The flu is not a cold, just as a tiger is never a cat,” so today I want to talk about the flu again and also update the knowledge about the use of flu medication.

Generally, children with the flu without complications will gradually recover in about a week, but some symptoms (especially cough) may persist, especially in young children, while the weakness and fatigue in older children may last for several weeks.

Therefore, for children who are suspected or diagnosed with the flu, doctors may provide symptomatic treatment and/or antiviral treatment.

Commonly used antiviral drugs include oseltamivir and baloxavir, and some hospitals use peramivir.

Different drugs have different applicable ages and methods of administration, and the most suitable plan can be discussed with a doctor.

Generally, for children with severe influenza, such as those who are hospitalized, have severe complications, or are deteriorating, antiviral treatment is recommended.

Oral oseltamivir is preferred for severe cases because there is stronger evidence for its use in severe pediatric patients. If oral medication is not possible, a single intravenous dose of peramivir may be given, but there is a lack of research confirming the benefits of this drug for treating severe influenza.

There is no research on baloxavir in severe influenza patients.

For children without severe manifestations, who are diagnosed with or suspected of having influenza, the indications for antiviral treatment include:

Children who meet the above criteria, regardless of whether they have been vaccinated with the seasonal influenza vaccine, are recommended to receive antiviral treatment.

For children who do not meet the above two situations, since influenza often presents as a self-limited disease course, antiviral treatment is not necessary.

However,

if the time from onset of illness is less than 48 hours, there is evidence that antiviral treatment can shorten the duration of symptoms, it is recommended to discuss with parents and doctors based on the severity of the child’s symptoms to decide whether to treat.

Below is a separate explanation of the applicable age, dosage, and precautions for each drug:

Oseltamivir is the most commonly used drug, which can shorten the duration of influenza symptoms by about 1 day compared to a placebo.

Neuraminidase inhibitor drugs, represented by oseltamivir, are rare in the development of drug resistance, and the resistance monitoring reported by the China CDC also shows that

the vast majority of the monitored influenza A strains are sensitive to oseltamivir.

Applicable age:

The instructions for oseltamivir in China require it to be used for children over 1 year old, but the United States has approved the drug for the treatment of influenza patients aged ≥2 weeks, and it can also be used for newborns under 2 weeks when necessary.

Dosage:

Oseltamivir is an oral medication and usually needs to be taken for 5 days, and severely ill patients may require longer treatment.

The common adverse reactions of oseltamivir are gastrointestinal discomforts, such as nausea (8%-10%), vomiting (8%-16%), diarrhea (7%), and headache (2%-17%).

Compared to a placebo, baloxavir can also shorten the duration of influenza symptoms by about 1 day.

The drug is as effective as oseltamivir against influenza A and may be more effective against influenza B.

Therefore, baloxavir is more recommended for influenza B.

Clinical trials show that baloxavir is more likely to develop resistance, but the resistance monitoring reported by the China CDC shows that there is no resistance found in the monitored influenza A strains so far.

Applicable age:

Baloxavir is approved for use in children aged ≥5 years in the United States and China, but Japan and the European Union have approved it for use in children aged ≥1 year.

Dosage:

Baloxavir is also an oral medication and only needs to be taken once.

The characteristic of a single dose is more friendly for babies who have difficulty taking medication.

Baloxavir also has gastrointestinal adverse reactions, such as diarrhea occurring in 2% of adolescents and adult patients, and 5% in children, and vomiting occurs in 6%.

Compared to oseltamivir, it is lower.

Applicable age:

Peramivir, like oseltamivir, is approved by the United States for the treatment of influenza patients aged ≥6 months with symptoms lasting ≤2 days.

Peramivir needs to be administered intravenously, so it is more suitable for patients who cannot take oral medication or need to be hospitalized.

Dosage:

Peramivir needs to be administered intravenously, so it is more suitable for patients who cannot take oral medication or need to be hospitalized, and its dosage depends on age.

If necessary, the above antiviral drugs should be started as soon as possible after the onset of symptoms. (preferably within 48 hours).

However, for hospitalized children, children with severe complications or progressive disease, and children at high risk of complications, it is also beneficial to use oseltamivir after more than 48 hours after the onset of symptoms, while there is a lack of information on the effectiveness of starting baloxavir treatment after >48 hours after the onset of symptoms.

So, should antibiotics be used?

Actually, antibiotics are ineffective against the influenza virus, so for children diagnosed with the flu,

antibiotics are only used in cases of confirmed or strongly suspected bacterial complications, such as bacterial pneumonia, acute otitis media, and sinusitis.

The main route of transmission for the influenza virus is direct person-to-person transmission via respiratory tract. When infected individuals cough, sneeze, or speak, the virus in their respiratory secretions is inhaled or contacted by others within close range (about 2 meters), causing infection and transmission.

Contact with objects or surfaces contaminated with respiratory secretions from infected individuals and then touching one’s own eyes, nose, or mouth can also result in the spread of the influenza virus.

Therefore, developing good hygiene habits helps prevent respiratory diseases, including the flu. It is recommended that everyone wash their hands frequently (especially after going out), avoid touching their mouth and nose;

stay away from sick people;

avoid crowded places (for example, shopping malls, restaurants, indoor playgrounds, etc.) and/or wear masks;

ensure good ventilation at home, try to open windows to get fresh air.

Additionally, getting vaccinated and chemical prevention when necessary are also important.

Getting vaccinated against the flu is the most effective way to prevent the flu. Although the flu vaccine cannot 100% prevent infection, it can alleviate the symptoms of infection and greatly reduce the risk of severe illness and complications after infection.

If there are no contraindications to vaccination, it is recommended that everyone aged ≥6 months get vaccinated against the flu every year.

Especially recommended for the following groups to get vaccinated against the flu:

Under certain specific circumstances, antiviral drugs can be used for prevention (also known as chemoprophylaxis).

Studies have shown that compared to a placebo, using neuraminidase inhibitors (e.g., oseltamivir) or baloxavir for chemoprophylaxis can reduce the risk of laboratory-confirmed symptomatic influenza, but it needs to be emphasized that medication prophylaxis cannot replace vaccination, and it is not recommended for routine use, because:

Based on the above considerations, it is recommended to conduct post-exposure drug prophylaxis for children who are ≥3 months old, meet the following conditions, and have a history of influenza exposure within 48 hours: