Influenza vaccine 2019: the vaccine is working well this year, especially for children

The first indication of flu vaccine effectiveness this season in America has just been released – and this may help explain why this year's influenza season is milder than last year.

Disease Control and Prevention Centers measure the effectiveness of the vaccine by examining the number of people with influenza cases in doctors' offices and hospitals, as well as the total number of hospitalizations and deaths related to influenza .

According to the weekly report on morbidity and mortality on February 15, people who have been vaccinated this season have halved the risk of needing medical attention for serious complications of influenza. As a reminder, last year's influenza vaccine reduced the risk of infection with the influenza strain most often circulating by a quarter. It was also one of the worst influenza seasons of recent history, with 80,000 deaths associated with the flu (more than road crashes, gun violence or opioid overdoses) .

The effectiveness of the influenza vaccine changes every year due to the changing influenza strains in circulation, as well as the vaccine recipe. Before the influenza season, public health agencies make informed assumptions about what strains and mutations they think will be around. As you can imagine, this is not an easy task. And they do not always do things correctly.

In a good year, the effectiveness of the influenza vaccine ranges from 50 to 70%. Thus, this year's first vaccine data suggest that the season is getting softer, and more so for one of the most vulnerable groups to the flu: children.

In children 6 months to 17 years, the effectiveness of the vaccine to date is 61%. Considering how small the flu can be in children, this finding is encouraging. This is a reminder that encourages your children to get vaccinated if you have not already taken the picture. (We're still in the middle of a flu season, which may last until May.) Here are three things parents should know about influenza and the flu vaccine.

1) The flu occurs much faster than a cold

Seasonal flu is a respiratory illness that can cause fever, chills, headaches, discomfort, muscle aches, coughing and sore throat. These symptoms appear very quickly – within 24 hours or so – and should improve over a week (but may last a little longer in younger people). Children with influenza can also have vomiting, diarrhea, nausea and stomach pain.

Because flu is sometimes mistaken for colds, the CDC has a very useful infographic to make a difference:

So far this season, the CDC estimates that nearly 15.2 million people have contracted the flu, from 155,000 to 186,000 were hospitalized because of the virus, and that it caused between 9 600 and 15,900 deaths (including 28 children) between October 1, 2018 and the beginning of the month. February 2, 2019.

2) Children under 5 years of age with certain medical conditions require special attention if they have flu symptoms.

For most children, flu does not cause serious complications and can be treated at home with plenty of rest and fluids.

However, some groups should consult a doctor sooner if they have the flu. Children under 5 years – and especially those under 2 years – are considered particularly vulnerable to serious complications related to the flu, such as pneumonia or encephalitis. And according to UpToDate, the evidence-based physician's resource, these medical conditions also expose children and adults to a high risk of flu complications:

• Asthma
• Renal disorders
• Liver disorders
• Blood disorders (including sickle cell disease)
• Endocrine disorders (including diabetes mellitus)
• Metabolic Disorders (including Hereditary Metabolic Disorders and Mitochondrial Disorders)
• Neurological and developmental neurological disorders (including disorders of the brain, spinal cord, peripheral nerves and muscles such as cerebral palsy, epilepsy, stroke, intellectual disability, moderate to severe developmental delay, muscular dystrophy and spinal cord)
• Chronic lung disease (such as chronic obstructive pulmonary disease and cystic fibrosis)
• Heart disease (except hypertension)
• Immunosuppression due to illness or treatment (including HIV, cancer and chronic glucocorticoids)
• Long-term aspirin therapy

So, if your child is under 5 years old and / or has one of these conditions and you suspect that he has the flu, you may need to see a doctor immediately.

3) There are warning signs to watch for in all children – and reasons to rush to the hospital

Although deaths from influenza are rare, even children with no underlying medical problem are still at risk of dying of the flu. "They are young and immature – immunologically – from the treatment of the flu," said last year Wendy Sue Swanson, pediatrician and spokesperson for the American Academy of Pediatrics.

In a study of deaths from influenza among children in the United States between 2004 and 2012, 43% of children did not suffer from high-risk health problems, 33% had neurological disorders and 12% had genetic disorders. or chromosomes. These conclusions were reaffirmed in February pediatrics study, which focused on the 2010-2016 influenza seasons.

In all children, there are other warning signs to watch that may require prompt medical attention.

If your child continues to worsen, not better: Children with influenza should gradually improve over a week (although symptoms may last longer). But if their symptoms worsen with time – fevers or pain worsen every day – you may want to see a doctor right away.

If your child recovers, he becomes sick again: Each year, about half of all child deaths from influenza occur in otherwise healthy children. Swanson said he heard anecdotes that some of the deaths this year involved children who had the flu but were again sick with another secondary infection. "That tells me that they had a viral infection caused by the flu, that their body was trying to get rid of the virus, but that they had then been prepared for a secondary infection – a serious infection of the liver." ear or pneumonia, "said Swanson. So, if your child is getting better and his condition worsens, see a doctor.

If your child has any of these other warning signs urgently of the CDC:

• Rapid breathing or difficulty breathing
• Bluish skin color
• Do not drink enough liquids
• Do not wake up or interact
• Being so irritable that the child does not want to be restrained
• Flu-like symptoms that improve and then come back with fever and aggravated cough
• Fever with rash

In infants, warning signs include:

• Being unable to eat
• Wheeze
• Do not have tears crying
• Much less wet diapers than normal

"If your child does not stay hydrated, can not keep anything or has a febrile fit – or if something is really different from an ordinary cold – trust your instinct," Swanson added. "It's worth being seen right now."

If your child has not been vaccinated against influenza: Influenza vaccines, although imperfect, can reduce the risk of getting the flu and reduce the severity of the disease, which can be particularly important for vulnerable groups such as children. In a study on Influenza-Related Infant Mortality and Immunization Status, researchers found that only 26% of those who died had been vaccinated. Last year, 80% of pediatric deaths occurred in unvaccinated children, according to the CDC.

So far, 28 children have died from flu-related complications during the influenza season, and only three of the 22 who had died from influenza and who met the conditions to benefit from the vaccine had been completely eliminated. vaccinated.

Unfortunately, there is no sure cure for the flu. Antivirals do not always work well but are most effective when they are given within 48 hours of the onset of the flu (and are recommended for high-risk groups, such as young children). Otherwise, plenty of rest and fluids are essential and over-the-counter pain relievers such as acetaminophen or ibuprofen can relieve pain and fever. (Vitamin C does not really help.)

So watch for the warning signs, but remember: the vast majority of children with flu, like most adults, will recover.

Further reading