FLU Viruses: What Should a Parent Know

Influenza or Flu is a respiratory illness caused by influenza A or B viruses commonly and rarely by influenza C viruses. Flu causes outbreaks globally every year, mainly during the winter seasons. Influenza mostly is a self-limited disease in healthy children, but it can cause severe morbidity and mortality in high-risk children. High-risk groups are Children <5 years, but especially <2 years are very vulnerable and also children with underlying medical conditions like Asthma, Neurological disorders, lung diseases, heart diseases, cancer and immunocompromised conditions.

How is it spread? 

Influenza viruses are spread through aerosol route like COVID virus from person to person, through contact with respiratory secretions or through contaminated objects. The incubation period is usually one to four days (average of two days), and this virus is highly contagious. The transmission period varies from 1-2 days prior to onset of symptoms to 3-4 days after the onset of symptoms.

How does it show up?

A flu viral infection presents as fever, headache, myalgias, cough, cold and sore throat. Few children present with high fever, Loose stools and vomiting also. H1N1 and H3 N2 flu infections have been associated with very severe symptoms especially in pandemics. Children with uncomplicated flu usually improve over 5-7 days’ time with or without treatment but cough can persist for 2-3 weeks, and weakness can continue for few weeks in bigger children. 

Complications

Few children especially children younger than 2 years develop complications like pneumonia which can progress very fast leading sometimes to requirement of ventilator and death also. Other complications like ear infections, bronchitis and exacerbation of asthma can occur after a flu infection. Few children with flu develop secondary bacterial infections with other organisms leading to severe morbidity and mortality. 

How do you suspect and treat

During flu season any child presenting with high fever and respiratory symptoms should be suspected to be infected with Influenza viruses and early treatment in the vulnerable population can cure the child faster and with better results. Usually giving enough rest and adequate fluids to the child will help until support the child during the illness. Giving paracetamol or if the fever is high sometimes after consultation with your pediatrician medicines like Ibuprofen are effective in controlling the fever and body aches.

What can I do?

Give enough fluids so that your kid doesn’t become dehydrated.  One way to judge if you are drinking enough is to look at the color of your urine. Normally, urine should be light yellow to nearly colorless and should be passing urine every three to five hours. Treatment of Influenza infection is by antiviral drugs like Oseltamivir, Zanamivir. Antiviral therapy is most effective when it is administered within the first 48 hours of symptom onset, however it is indicated beyond 48 hours in severely ill patients and patients with certain underlying medical conditions and the immunocompromised children.

Does one infection give immunity to other flu viruses.

Multiple influenza virus strains circulate in any given season and of them H3 N2 sometimes H1N1 are seen but importantly for parents they have to understand that infection with one type of virus does not provide immunity to the other types. 

How are the vaccine strains decided?

WHO constantly monitors the flu causing strains every year and based on the previous year’s strains it releases the recommendations for the next year which varies based on whether you are in the Northern hemisphere or Southern. As soon as they are released the vaccine companies manufacture the year’s vaccine and release usually before the winter. The effectiveness of the flu vaccine is dependent on the strains in the vaccine and the viruses that are currently in circulation. Although effectiveness is decreased when the strains in circulation do not match the vaccine strains, influenza vaccination is known to decrease influenza morbidity and mortality and to also it reduces the severity of the disease. CDC USA estimates that the effectiveness of the flu vaccines is around 50-55% in preventing Influenza.

INFECTION CONTROL

Infection control measures, like handwashing and covering the mouth when coughing can help preventing the spread of influenza.  Frequent handwashing with soap and water and usage of sanitizer can help limit the spread of influenza. Avoid your kids close contact with sick people and don’t send the child to the school if not feeling well.

Dr. Dinesh Kumar Chirla – Director of Intensive Care Services in Hyderabad | Rainbow Children’s Hospital

Dr. Dinesh Kumar Chirla

Director Intensive Care Services, Rainbow Children’s Hospital, Banjara Hills, Hyderabad

Dr. Preetham Kumar Reddy, Pediatrician & Pediatric Intensivist, Rainbow Children’s Hospital

Dr. Preetham Kumar Reddy

Pediatrician & Pediatric Intensivist, Rainbow Children’s Hospital, Karkhana, Secunderabad