Vector-Borne Diseases Flashcards
Give examples of non-mosquito vectors.
Ticks
Bugs/Flies
Snails
What is Lyme Disease?
Also called Lyme borreliosis
It is a tick-borne multisystem disease caused by the spirochaete Borrelia burgdorferi.
It is mainly northern hemisphere - Europe and US.
Presentation of Lyme Disease.
Around 75% will remember the tick bite.
Peak infection is withing 48-72h of attachment.
Then follows stages;
Early localised - 3-30d after bite with erythema migrans, pain/pruritus, lymphadenopathy +/- constitutional symptoms like fever, malaise and headaches.
Early disseminated - Weeks to months after bite with borrelial lymphocytoma and neuroborreliosis + carditis.
Late disseminated - Months to years after bites. Acrodermatitis chronic atrophicans and lyme arthritis.
Explain lymphocytoma in in Lyme disease.
Bluish-red plaque/nodule where you should check earlobes, nipples and genitals.
Explain neuroborreliosis in Lyme disease.
Lymphocytic meningitis
Ataxia
manesia
Facial/cranial nerve palsies
Neuropathy
Encephalomyelitis
Diagnosis of Lyme disease.
Clinical with erythema migrans + known exposure.
Borrelia culture, PCR.
Two-tier serology due to false-positive reaction with other spriochaete infection.
Enzyme immunoassay/immunofluoresecence + immunoblot.
Treatment of Lyme Disease.
Doxycycline for erythema migrans. Can also give amoxicillin, phenoxymethylpenicillin, azithromycin.
Ceftriaxone or IV benzylpenicllin or doxycycline in Neuroborreliosis.
Doxyciline or amoxicillin or ceftriaxone if arthritis or carditis.
Prevention of Lyme Disease.
Keep limbs covered.
Use insect repellent
Inspect skin and remove ticks.
What is Rickettsial disease?
Rickettsiae are obligate, intracellular coccobacillary forms lying between bacteria and viruses.
It is gram-negative.
Mammals and arthropods are natural hosts.
More common in camping, hiking, hunting etc…
What is Rickettsial diease divided into?
Spotted fevers
Typhus
etc…
Presentation of Rickettsial disease.
INcubation 1-2 weeks.
Fever
Headache
Malaise
Rash
N+V
Myalgia
There might be lymphadenopathy and an eschar at the site of the bite.
Diagnosis of Rickettsial disease.
Clinical fever + rash + travel to endemic area
Serology, culture/PCR of blood/skin biopsy.
Treatment of Rickettsial disease.
Doxycycline, azithromycin, chloramphenicol.
What is Chaga’s disease?
A life-threatening illness due to protozoan Trypanosoma crusi which is transmitted by triatomine bugs.
Where is Chagas’ disease endemic?
Latin America
