Influenza is an acute respiratory tract disease caused by the influenza A and B virus that typically shows an increase in cases worldwide during the winter.
Transmission
Large amounts of the virus are found in the respiratory secretions of the patient, so, when they are coughing or sneezing they have a great possibility of infecting people who have contact with these secretions.
A patient may be contagious for an average of 5 days from the onset of the disease, but may reach 7 or 10 especially in children and the elderly.
Seasonal Influenza Symptoms
Uncomplicated influenza can typically show Following symptoms:
- Fever
- Headache
- Muscle aches
- Malaise
These start after an incubation period of 1 to 4 days after exposure to the virus.
In addition to the symptoms mentioned above we can find respiratory manifestations such as:
- Cough
- sore throat
- Nasal runoff
Complications
The biggest complication of influenza is pneumonia and most often presented are patients with degenerative diseases as diabetes, hypertension or obesity.
Pneumonia can be primary viral, secondary to a bacteria or mixed.
Diagnosis
The diagnosis during the season of greater presence of the disease is clinical in most cases and leaves confirmation of laboratory for suspicious or risk cases.
During the rest of the year, confirmation by laboratory is the most appropriate.
The most preferred laboratory studies are the molecular studies (PCR) although there are also antigen detection studies, they are cheaper but less sensitive (higher rate of false negatives).
A patient suspected of influenza with a negative result in the antigen test should be confirmed by PCR (molecular test).
Prevention
The influenza virus has a high rate of mutation, so each year new vaccines are prepared that can combat the circulating strains of the virus. Current vaccines are trivalent (3 viruses) and tetravalent (4 viruses). The protection we acquire from these vaccines is through the generation of antibodies against different strains of the virus.
Who can get a flu shot?
Men, women and children from 6 months of age with special emphasis on children and seniors, as well as people with pre-existing diseases, obesity and workers in the health sector.
There are two types of vaccines, those that contain inactive (dead) viruses and those that contain attenuated (live) viruses. The inactivated virus vaccine is the one that has shown the best results, being the safest for pregnant women and allergic to eggs.
If you had contact with a patient diagnosed with influenza and you have not been vaccinated, there is a prophylactic treatment that prevents the disease with the use of specific antivirals. This treatment should not be substituted for vaccination because the vaccine offers better protection against the complications of the disease.
In addition, the best prevention measures are those aimed at reducing the transmission of the virus such as constant hand washing, limited physical contact, avoiding crowded places and the use of face masks.
Influenza treatment
Antiviral treatment should be administered within the first 48 hours of the disease to ensure efficacy and should not be delayed by confirmatory diagnostic tests in patients with high suspicion.
The recommended antivirals are Oseltamivir, Zanamivir and Baloxavir. Being the most used Oseltamivir for its effectiveness. Antivirals such as Amantadine are not recommended given the high rate of resistance that viruses present to them.
We hope this information can be useful and remember that any symptom is best to go to the doctor or better that the doctor comes to your home to review, if you want a doctor at home just click here to schedule your appointment.
Source: uptodate.com