lyme disease

What is erythema migrans?

The characteristic "bull's-eye" rash seen in Lyme disease.

Which disease is associated with erythema migrans?

Lyme disease.

During which stage of Lyme disease does erythema migrans occur?

The early localized stage.

When does erythema migrans usually appear after a tick bite?

A few days to several weeks after the bite.

What causes erythema migrans?

Borrelia burgdorferi spreads outward from the tick bite site, causing inflammation in the skin.

What does erythema migrans look like?

A red expanding rash that often has a bull's-eye appearance.

What are the three stages of Lyme disease?

Early localized, early disseminated, and late persistent.

How can Lyme disease affect the heart during the early disseminated stage?

It can impair the electrical conduction system of the heart.

What causes Lyme disease?

Borrelia burgdorferi.

What type of bacterium is Borrelia burgdorferi?

A Gram-negative, microaerophilic spirochete.

How does Lyme disease begin?

An infected tick bites a person and injects Borrelia burgdorferi into the skin.

What happens after Borrelia burgdorferi enters the skin?

The bacteria multiply and spread outward, causing erythema migrans.

What causes the skin inflammation seen in Lyme disease?

Lipopolysaccharide (LPS) from Borrelia burgdorferi.

What causes many symptoms of Lyme disease?

The host's intense inflammatory response to bacterial antigens.

What may contribute to chronic symptoms of Lyme disease?

A possible autoimmune response.

What virulence characteristic allows Borrelia burgdorferi to spread through tissues?

Its spirochete shape allows it to move through tissues efficiently.

Is Lyme disease a zoonosis?

Yes, humans are accidental hosts.

What is the primary vector for Lyme disease?

Ixodes scapularis (black-legged deer tick).

Which stage of the tick most commonly transmits Lyme disease?

The nymph stage.

What animal is the preferred host for adult ticks?

Deer

When are antibiotics most effective for Lyme disease?

During the early stages of infection.

Why are antibiotics less effective in late Lyme disease?

The bacteria may not be actively multiplying.

What antibiotics may be used for severe or late Lyme disease?

Ampicillin or ceftriaxone.

How can Lyme disease be prevented?

Avoid tick exposure, wear protective clothing, and use insect repellents.

What can reduce the risk of Lyme disease after a tick bite?

A prophylactic dose of doxycycline within 72 hours.