TABLE OF CONTENTS

1. What Is Flu (Influenza)?
2. Causes of Flu (Influenza)
3. Risk Factors for Flu (Influenza)
4. Influenza Transmission Patterns
5. Symptoms of Flu (Influenza)
6. Recommended Medications for Influenza
7. Flu (Influenza) Diagnosis
8. Flu Complications
9. Treatment of Flu (Influenza)
10. Prevention of Flu (Influenza)
11. Influenza Vaccination at Home with Halodoc

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What Is Flu (Influenza)?

Flu, or influenza, is an illness caused by a virus that can infect the nose, throat, and lungs. It is very common during transitional seasons (pancaroba) and highly contagious, especially during the first 3–4 days after infection. 

Typical symptoms include fever, headache, persistent cough, muscle aches, loss of appetite, and sore throat. 

Symptoms usually intensify over 2–4 days before gradually improving and resolving.

Although often confused with the common cold, influenza tends to present more severe symptoms and a shorter incubation period, making it more disruptive to daily life.

Causes of Flu (Influenza)

Influenza is transmitted through respiratory droplets when an infected person coughs, sneezes, or speaks. 

You may inhale these droplets or contract the virus by touching contaminated surfaces and then touching your eyes, nose, or mouth. 

Infectiousness begins about one day before symptoms appear and can persist up to five days after. Children and immunocompromised individuals may remain contagious longer.

Risk Factors for Flu (Influenza)

While anyone can get the flu, certain groups are more vulnerable:

• Individuals with weakened immune systems
• Pregnant or postpartum women
• Young children and older adults
• People with chronic conditions (e.g., diabetes, asthma, heart disease, obesity)
• Those living or working in crowded places
• People who are fatigued or under-rested.

Influenza Transmission Patterns: Seasonality, Epidemics, and Pandemics

Influenza exhibits complex patterns of spread seasonally, epidemically, and pandemically. Transmission mainly occurs via droplets. 

Factors influencing spread include population density, personal hygiene, and environmental conditions (temperature and humidity).

Seasonal flu peaks in colder months in temperate regions, due to dry, cold air stabilizing the virus and lowering mucosal defenses. Vitamin D deficiency in winter has also been linked to higher susceptibility to flu. 

Mathematical models help predict flu seasons based on transmission data, immunity levels, and environment.

Influenza affects not only humans but also animals (birds, pigs, other mammals). Animal outbreaks (epizootics), such as avian influenza (e.g., H5N1), raise concerns about zoonotic transmission. Monitoring animal flu strains is vital to prevent potential human pandemics.

Cultural and Historical Impact of Influenza

Influenza has shaped human history and culture for centuries. The term “influenza” comes from the Italian influenza del freddo (“influence of the cold”), reflecting early beliefs that cold air or astrology caused illness.

Historically, other terms included “grippe” and “epidemic catarrh.” Some historians suspect that diseases brought to the Americas by Columbus’s crew included influenza, contributing to indigenous population decline.

Major influenza pandemics:

• 1830–1833: One of the earliest well-documented global influenza outbreaks.
• 1918 Spanish flu: The most lethal modern pandemic, causing tens of millions of deaths worldwide.
• 2009 H1N1 pandemic: A notable contemporary outbreak reminding the world of pandemic risks.

Cultural influences include:

• Representation in art, literature, film, and music reflecting fear, loss, and resilience during outbreaks
• Advances in public health practices such as hygiene, isolation, and viral research spurred by pandemics
• Collective memory shaping how societies view infectious diseases and health systems.

Symptoms of Flu (Influenza)

At first, flu symptoms may resemble a common cold, runny nose, sneezing, and sore throat. Common flu symptoms:

• Fever
• Muscle aches
• Chills and sweating
• Headache
• Persistent dry cough
• Shortness of breath
• Fatigue and weakness
• Runny or stuffy nose
• Sore throat
• Eye pain
• Vomiting and diarrhea (more common in children)

Symptoms typically appear 2–3 days after infection and resolve within a week; however, cough and fatigue may linger for weeks. 

If symptoms worsen, consult a doctor for prompt care.

Recommended Medications for Flu

Available over the counter via Halodoc’s Health Store:

• Vicks Formula 44 Syrup 100 ml – contains dextromethorphan HBr and doxylamine succinate for dry cough and allergic sneezing
• Rhinos SR 10 Capsules – relieves allergic rhinitis symptoms such as flu, sneezing, and nasal congestion
• Intunal F 10 Tablets – reduces fever, headache, nasal congestion, sneezing, and cough
• Panadol Cold & Flu 10 Caplets – contains paracetamol, pseudoephedrine HCl, and dextromethorphan HBr for fever, headache, congestion, and dry cough
• Nalgestan 4 Tablets – features phenylpropanolamine HCl and chlorpheniramine maleate to relieve sneezing and nasal congestion
• Anadex 10 Caplets – combats fever, headache, sneezing, nasal congestion, and cough; may cause drowsiness
• Demacolin 10 Tablets – contains paracetamol, pseudoephedrine HCl, and chlorpheniramine maleate for fever, headache, congestion, and sneezing
• Alpara 10 Caplets – treats flu symptoms like fever, headache, nasal congestion, and sneezing.

Flu (Influenza) Diagnosis

To diagnose flu, doctors usually:

1. Take medical history, symptoms such as congestion, sneezing, or hoarseness
2. Perform a physical exam, checking for fever
3. Order additional tests (e.g., blood tests) if symptoms persist over 10 days.

Flu Complications

Most people recover without complications. However, untreated flu may lead to:

• Heart problems
• Ear infections
• Pneumonia
• Bronchitis

Symptoms that subside but then recur may indicate a secondary infection, which should be evaluated promptly to prevent life-threatening complications like pneumonia.

Treatment of Flu (Influenza)

Flu generally resolves on its own with rest and hydration. Supportive care measures include:

• Regular handwashing to stop virus spread
• Covering mouth/nose with a tissue or elbow when coughing or sneezing, then disposing tissue
• Staying hydrated by drinking water, fruit juice, or warm soup
• Taking pain relievers like paracetamol to reduce fever and muscle pain

For prolonged or severe symptoms, consult a doctor. Some strains like avian flu require isolation and antiviral medication (e.g., oseltamivir or zanamivir) to speed recovery and prevent complications.

Prevention of Flu (Influenza)

Prevention begins with vaccination, especially for those at high risk of complications, such as:

• Adults aged 65+
• Infants with undeveloped immunity
• Pregnant women
• Individuals living with high‑risk people (e.g., immunocompromised, transplant recipients, cancer patients)
• Frontline healthcare workers

Vaccination does not offer 100% protection, and influenza remains highly contagious via droplets or contaminated surfaces. Additional preventive hygiene measures include:

• Washing hands frequently with soap and water for at least 20 seconds or using alcohol‑based sanitizers
• Avoiding touching your face before washing hands
• Disinfecting high‑touch surfaces
• Not sharing personal items like utensils or drinkware

If you do get the flu, reduce spread by:

• Avoiding close contact for at least 24 hours after fever subsides
• Wearing a mask when leaving home
• Covering coughs/sneezes, disposing tissue, and washing hands

Influenza Vaccination at Home with Halodoc

Untreated flu symptoms can escalate to serious conditions like bronchitis or pneumonia. Get vaccinated to reduce those risks, right from home!

Homecare by Halodoc (available in Jabodetabek, Bandung, Semarang, Yogyakarta, Surabaya, and Denpasar) offers Influenza vaccination (Vaxigrip Tetra) at your preferred location.

Advantages of Homecare Vaccination:

• Administered 100% by licensed vaccination doctors
• Strict health protocols
• Post‑vaccination observation
• Officially registered vaccines (BPOM‑approved and from international suppliers)
• Saves time and cost
• Prices start at IDR 440,000; combo vaccine (flu + pneumonia) IDR 1,334,000; family bookings offer extra discounts
• No queues or extra fees
• Free IDR 25,000 Halodoc voucher after service
• Promo code KEBALFLU2 reduces Vaxigrip Tetra to IDR 365,000

Book anytime via Halodoc app or WhatsApp at 0888‑0999‑9226.

You can also contact our English-speaking doctor on Halodoc to get more detailed information about influenza or influenza vaccination.

Reach a doctor directly from your smartphone using the Halodoc app. Doctors are available 24 hours to answer your questions.

Now, you can purchase 100% original and trusted health products from the Halodoc Health Store. No need to leave home, delivery in just 1 hour!

So, what are you waiting for? Download the Halodoc app on Play Store or App Store today!

References:

Healthline. Accessed in 2025. Everything You Need to Know About the Flu; What Causes the Flu?

Mayo Clinic. Accessed in 2025. Influenza (Flu).

Medical News Today. Accessed in 2025. All You Need to Know About Flu.

National Institutes of Health (MedlinePlus). Accessed in 2025. Flu.

FAQs

1. What causes the flu?

Influenza is caused by influenza viruses transmitted by respiratory droplets (coughs/sneezes) or direct contact with contaminated surfaces, which then touch the face.

2. What should I do if I get the flu?

• Rest well
• Stay hydrated
• Eat nutritious food
• Use warm compresses for fever and aches
• Take symptom-relief meds (e.g., paracetamol, cough/cold medicine as advised)
• Avoid close contact to prevent transmission

3. How can I recover from the flu faster?

There’s no instant cure, most cases resolve in a few days to a week. But rest, fluids, medications, and good care can speed recovery.

4. What causes the common cold?

The common cold is caused by viruses different from influenza, affecting the upper respiratory tract. Symptoms are milder and usually do not include high fever.