Flu

Overview

That achey, stuffy, sniffly feeling

The flu has many of the same symptoms as the common cold, and at first you may think you just have a bad cold. But the flu strikes suddenly and brings with it more severe symptoms, including fevers higher than 103°F.

The virus that causes the flu is very self-sufficient. It can live outside the body for up to three days. You can pick it up from virtually anything you touch, be it a doorknob, book, or countertop. But you won't "catch" the flu unless the virus finds its way into the body via the eyes, nose, or mouth — so wash your hands frequently to reduce the likelihood of this happening. Luckily, there is a vaccine and the yearly shot is the best way to avoid getting sick. A recent study found it to be nearly 90% effective in preventing the illness. Despite all the counsel and lore to be had on flu — from lemon tea to garlic tonics — if you do get it, the flu generally needs to run its course. For most people, the fastest road to recovery is good old rest and relaxation.

Detailed Description

There are three different types of flu:

  • Type A: the most common
  • Type B: like Type A, it circulates every year, but tends to be weaker
  • Type C: the least serious and least common (it comes around every two to three years)

Types A and B are mutating viruses, meaning they change slightly from year to year. Scientists develop new vaccines each fall to combat what they believe will be the most widespread version the following winter. That's why last year's shot won't protect you this year.

Flu season in the United States runs roughly from fall through winter with its peak being December to March. Influenza is so contagious that it can spread through a community in less than a month infecting up to 40% of people living or working within that community.

The flu is more serious than the common cold partly because it can bring on secondary bacterial infections like pneumonia, bronchitis, and acute sinus and middle-ear infections. If you are sick for more than a week, see your doctor. He or she can prescribe antibiotics to treat any bacterial infection you may have developed (but don't ask for antibiotics to treat the flu — they're powerless against viral infections).

How Common Is the Flu?

Very common — there are 25 to 50 million cases each year in the United States. Children, who are more susceptible than adults, have annual infection rates of 10% to 40%. While it's rarely lethal in young, healthy people the flu can be deadly — 20,000 people die due to it each year. Most deaths happen to people over 75. That's why the flu shot is routinely recommended for everyone over the age of 65. (As well as younger adults with chronic heart or lung problems).

What You Can Expect

Left untreated, the flu will typically lay you low for about a week. And you'll probably feel weak for another several days.

Conventional Treatment

Goals of Treatment

There is no cure for the flu, so it's best to try and avoid getting sick in the first place. Eat right, exercise, wash your hands frequently, and, if possible, steer clear of anyone who has the flu. Adults are only contagious for three to five days, but kids can remain contagious for up to 10 days. The best insurance policy is the annual vaccination. It's nearly 90% effective in preventing the illness. Vaccines are available from late October to early January.

The virus generally takes its course whether it is treated or not. Over-the-counter medications won't help you recover any faster, but they will make you feel better in the meantime. Try gargling with double-strength tea or salt water to ease a sore throat. If you still feel lousy after a week, call your doctor.

Drug Therapy

Antivirals

Symmetrel

On-Label Efficacy

Relenza

On-Label Efficacy

Tamiflu

On-Label Efficacy
Antibiotics

Antibiotics only treat bacterial complications — like bacterial pneumonia or bacterial sinus infections — not the primary viral infection such as the flu itself. But these infections can be brought on by a bad case of the flu.

Other

Ibuprofen

On-Label Efficacy

Monitoring the Condition

No follow-up is necessary if you're feeling better after a week to 10 days. And remember it's normal to tire easily in the week after you've recovered, so, if possible, you may want to continue to take it easy. If complications such as a bacterial sinus infection develop, you may need to take a course of antibiotics, in which case you probably won't be back to your old self for three to six weeks.

Possible Complications

  • Bacterial infections of the sinuses, ears, or lungs
  • Pneumonia
  • Bronchitis
  • Reye's syndrome (only in children under the age of 18)
  • Croup
  • Death

Activity and Diet Restrictions

The only good thing about the flu is it's a perfect excuse to stay in bed. Your body needs to focus all its energy on ridding itself of the virus, so relaxation, especially if you have a fever, seems to be the best medicine. Drink plenty of extra fluids such as fruit juice, tea, broth, or water. These can also help make the mucus in the lungs thinner and easier to cough up.

Quality of Life

Everyone gets sick with the flu from time to time — it's inevitable. But if you have a history of coming down with a particularly nasty bug every year, you should strongly consider getting an annual flu vaccine.

Considerations for Women

Pregnancy

Any healthy women who will be in her second or third trimester of pregnancy during flu season should ask her doctor about getting a flu shot. And if she is in a high-risk category for complications from the flu — such as a woman with asthma or in general poor health — she should probably get the vaccine regardless of what trimester she'll be in.

If your doctor prescribes an antiviral, make sure he or she knows you're pregnant.

Considerations for Children and Adolescents

The Haemophilus influenzae type b (Hib) vaccines that children receive in three to four doses before age 15 months provide no protection against the flu. Hib is a bacteria that can cause serious illnesses such as meningitis and is completely different from the influenza virus.

Do not give any child aspirin or aspirin-containing products. Aspirin can cause Reye's syndrome, a rare but often fatal complication, in children and teenagers.

Considerations for Older People

Immunizations are recommended for anyone over age 65. It can be extremely difficult for older people to recover from any complication brought on by influenza. So keep a close eye on older people who have the flu.

Flu

Last updated 6 November 2011

Synonyms

  • Influenza
  • Grippe

Causes

Established Causes

The flu is caused by influenza virus type A, B, and C.

Risk Factors

The flu is highly contagious, so everyone is at risk during flu season. If possible avoid:

  • Closed places such as nursing homes, schools, or prisons
  • Close contact with infected individuals
  • Stress, fatigue, and poor nutrition

Other risk factors include:

  • Recent illnesses
  • Chronic illness, especially of the respiratory system, but also AIDS and chronic heart or kidney disease

Risk factors are traits or behaviors that may make you statistically more likely than others in the general population to have a certain condition. They are not necessarily "causes" of the condition.


Symptoms & Diagnosis

  • Chills and high fever (usually above 103° F)
  • Muscle and body aches
  • Dry cough
  • Severe headache
  • Watering eyes
  • Nausea and vomiting, especially in children
  • Irritation of the upper respiratory system, including sore throat, runny nose, and hoarseness

Conditions That May Be Mistaken for the Flu

While the following conditions have some of the same symptoms as influenza, they're much less common:

  • Other respiratory viral infections
  • Mycoplasma pneumonia: symptoms include upper respiratory infection, dry cough, and fever
  • Q Fever: an acute respiratory illness accompanied by high fever
  • Tonsillitis
  • Infectious mononucleosis: "mono" usually causes severe fatigue
  • Coxsackievirus infections: also cause sore throat, headache, body ache, and breathing difficulties
  • Chlamydia pneumoniae: a microorganism that causes respiratory tract infections and pneumonia

How the Flu Is Diagnosed

The flu is usually self-diagnosed. Call your doctor if you are extremely sick or if you have any other chronic illness. She or he will probably perform one or more the following procedures:

  • Physical examination
  • Tissue culture of mucus lining of the nasal cavity
  • Rapid antigen test
  • Cell count of leukocytes or white blood cells

Self care & Prevention

Preventing the Flu

The major preventive measure for influenza has been the use of an inactivated influenza vaccine for the influenza A and B viruses that circulated during the previous influenza season. Up to 50% of individuals experience low-grade fever and mild systemic symptoms eight to 24 hours after vaccination. Since the vaccine is produced in eggs, individuals truly allergic to eggs should be desensitized or should not be vaccinated.

The U.S. Public Health Services recommends influenza vaccination for any person older than six months who is at increased risk for complication of influenza. Included are people with chronic heart or lung disease (including asthma) and residents of nursing homes and other continuous-care facilities. Other populations who need vaccination include healthy people over 65 years old or people with diabetes, renal diseases, blood disorders, or depressed immune systems. Individuals who work with these people should also get a vaccination to reduce likelihood of transmission.

Self-Care Measures

  • See your doctor if you have the flu longer than one week, as you are susceptible to secondary infections such as ear or sinus infections, bronchitis, and pneumonia. The very young and the very old are particularly prone to complications from flu.
  • Drink lots of nonalcoholic fluids. Flu can cause fever, and fever is dehydrating — which makes you feel even worse. Sip tea, juices, or water throughout the day. Hot fluids are even better than cold, as they help relieve the sore throat, nasal congestion, and cough of flu.
  • Rest. With flu, you have no alternative. Most people don't need more than one to three days at home, but don't drag yourself out if you feel you need more. That I-gotta-lie-down feeling is your body's way of directing all its energy into fighting the infection.
  • If you find yourself getting the flu repetitively, you may want to consider a flu vaccination. They are administered in the fall before the peak flu season that runs from December to March, and are specially re-engineered each year to elicit antibodies that attack the coming season's flu strains (type A flu strains change each year).