The flu is otherwise known as influenza. It is a viral infection that mainly attacks the respiratory system. It is highly infectious and may grow worse for some groups of people, with notable mention of young children, elderly individuals, and those suffering from an impaired immune system. This paper answers the formation, types, transmission, symptoms, complications, and available treatments of influenza.
Formation and Structure of the Influenza Virus
Influenza virus is part of the Orthomyxoviridae family and is an RNA virus. The shape of the virus is either spherical or filamentous and encloses a lipid membrane from the host cell. The outer surface of this virus is defined by two important glycoproteins:
Hemagglutinin (HA): helps in entry into the host cell by bonding to sialic acid receptors.
Neuraminidase (NA): assists the newly produced virus particles in escaping from the infected host cell of the virus.
The RNA genome of the virus is segmented, and this thus enables the virus to reassort. Reassortment is a process wherein genetic material coming from different viral strains mixes. This thus results in major changes to the genetic makeup of the virus and therefore to new strains of the virus.
Strains of Influenza Virus
There are four types of influenza viruses: A, B, C, and D. Of these, however, only influenza A and B viruses are known to cause major disease in humans.
Influenza A:
Types associated with the most severe type of influenza virus.
Can infect human beings, birds, pigs, or any other animal. It causes pandemics that can be very massive in scale. This is differentiated into various subtypes depending on its HA and NA proteins. There are, for example, H1N1 and H3N2.
Influenza B:
It is almost exclusively human-specific and does not have animal reservoirs, as with the case of influenza A.
It tends to cause less severe seasonal epidemics but can still result in more severe disease, especially among vulnerable populations. Influenza C:
This tends to cause only mild disease of the respiratory tract and has never been known to cause large outbreaks.
The virus primarily infects humans and pigs, but its impact is much less serious compared to influenza A or B.
Influenza D:
Primarily, it affects cattle and rarely infects humans.
Transmission of Influenza
Influenza mainly spreads through respiratory droplets that result from coughing, sneezing, or speaking by an infected person. The virus can also spread by touching contaminated surfaces by the droplets and then touching the face, more so the mouth, nose, or eyes. The virus survives in cold, dry climatic conditions; hence, influenza outbreaks occur often during the winter months.
Causes of Influenza
The flu begins very abruptly, but symptoms are not unlike others, such as a cold. However, flu symptoms are generally much more intense. Common symptoms include:
Fever or chills
Cough and sore throat
Muscle or body aches
Fatigue
Headaches
Sneezing or stuffy nose
Nausea or vomiting, especially in children.
These symptoms usually begin 1–4 days after being infected by the virus and may last up to a week.
Influenza Complications
Most patients recover from the flu in about a week or two, but some people are at risk of more dangerous complications. Those include the following:
Pneumonia
Bronchitis
Sinus infections
Acute exacerbation of chronic conditions (for example, asthma, heart disease)
Sepsis or multi-organ failure
These complications tend to be especially adverse to young children, older adults, women who are pregnant, and people whose immune systems are weakened.
Prevention and Vaccination
Annual vaccination is the only certain way to avert influenza. The virus mutates frequently, so there is the need for continually updating flu vaccines each year to combat the prevalent strains. The flu vaccine can cut down the severity of symptoms if the vaccinated person contracts the virus.
There are two vaccines:
Inactivated influenza vaccines (IIV): Injected vaccines with killed virus particles.
Live attenuated influenza vaccine (LAIV): nasal spray that consists of weakened live viruses, given to healthy, non-pregnant individuals between 2 and 49 years old.
Other preventive measures include:
Hand hygiene: Hand washing frequently with soap and water.
Cover the mouth and nose with a tissue when coughing or sneezing.
Avoiding close contact with those ill.
Disinfection of surfaces, where the virus may be known to have held on to.
Treatment of Influenza
Once the flu is caught by an individual, supportive care and antiviral medication are used to treat that condition.
Supportive Care:
Rest, fluids, and over-the-counter medications such as acetaminophen or ibuprofen alleviate symptoms of fever and body aches.
Fluid rehydration must be done to prevent dehydration, as dehydration further worsens flu symptoms.
Antiviral Medications:
The other antiviral drugs, if taken within 48 hours of the onset, help to reduce the duration of illness, which include oseltamivir, Tamiflu, zanamivir, Relenza, peramivir, rapivab, and baloxavir, Xofluza.
They can also use these drugs to prevent such severe complications as pneumonia, especially in the vulnerable patients.
Conclusion
Influenza is a common but serious viral infection that strikes millions of people across the globe each year. Familiarity with its structure, types, mode of transmission, symptoms, and treatment is, therefore, fundamental to the management and prevention of flu. Vaccination is the best preventive measure, while early treatment with antivirals will avoid bad outcomes. Being knowledgeable and taking precautions during flu season would go along in helping individuals and communities avoid the worse ravages of this contagious virus.
