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Quiz: The origins and veracity of urban legends about infections

Which of these statements about colds and the flu are true, and which are myths?

1 You can catch the flu from a flu shot.

2 Stress increases your chances of getting ill.

3 Wearing a hat will help protect you from a cold.

4 Flying on an airplane will increase your risk of getting sick.

5 Pregnant or breastfeeding women should not get vaccinated.

6 Increasing how much you sweat (for example, using lots of blankets) will speed up how quickly you resolve an infection.

7 “Feed a cold; starve a fever.”

8 Your grandmother’s chicken soup can help.

9 Eating garlic can help to prevent you from getting ill.

10 Over-the-counter cold “prevention” tablets or drinks are effective.

Answers

1 Myth: As discussed in Chapter 7, the injected flu vaccine is an inactivated virus; it is therefore impossible to get the flu from the shot itself. The nasal flu mist contains a live, but drastically weakened, virus, and it is highly unlikely that someone will get influenza from the nasal vaccine.

2 Not yet proven, but probably fact: stress alters hormones, hormones affect immunity, and immunity controls your response to viral infections, so it is quite possible that stress can affect your ability to respond to an infection.

3 Myth: Wearing a hat will keep your head warm, but that’s it.

4 Fact: Recirculated air combined with a large number of people in close quarters is a perfect recipe for transmission of respiratory infections from person to person.

5 Myth: Flu symptoms are generally worse in pregnant women than in nonpregnant women, so it is of added importance that pregnant women be vaccinated. Many studies have shown that there are no adverse consequences of maternal vaccination to the fetus or the nursing neonate.

6 Myth: While piling on the blankets may make you feel better, it will not make the cold go away faster; the only thing proven to alter the duration of an infection is the use of antivirals within a short (1- to 2-day) window after symptoms appear.

7 Myth: How much you eat, or what you eat, will not influence how quickly you will resolve an infection. However, drinking lots of fluids will help, as staying hydrated, especially if you have a fever, will keep the mucus in respiratory passages loose. Moreover, colds and flu tend to cause a transient lack of appetite, so choosing food wisely (for example, protein-rich) when recovering will hasten feeling better.

8 Fact!: It is a fact that warm liquids open up nasal passages and keep the mucus moving (a good thing), and chicken soup has also been proposed to mobilize neutrophils, important virus-fighting immune cells.

9 Fact: Garlic has powerful antioxidant activity, which boosts immunity. Eating lots of garlic will also repel potentially infected friends and colleagues.

10 Myth: The small bottles that often appear at checkout lines in supermarkets and that promise protection from catching a cold are primarily just a large dose (usually 1,000 mg) of vitamin C. While it remains controversial whether vitamin C is beneficial, daily multivitamins (or, better still, a healthy diet) can provide as much of the key ingredient and for less money.

A widely held belief is that large changes in temperature will increase a host’s susceptibility to infection. In fact, as a parent likely warned you, transmission of “the flu” (specifically, influenza A virus particles) is more efficient at low temperature and humidity, and this property could contribute to increased rates of influenza in the winter months (Box 1.10). However, epidemiological studies with rhinoviruses that are also anecdotally associated with cold temperatures have failed to support any relationship between being cold and getting a cold; whether the “urban legends” associated with respiratory viral infections are true thus appears to depend on the virus in question (Box 1.11).