Dr. Yansouni -- Vector-Borne Diseases Flashcards Preview

Block G -- Infection > Dr. Yansouni -- Vector-Borne Diseases > Flashcards

Flashcards in Dr. Yansouni -- Vector-Borne Diseases Deck (29)
1

Vector for malaria

Anopheles mosquitoes

2

Vector for Dengue

Aedes mosquitoes

3

Vector for West Nile virus

Culex mosquitoes

4

Vector for lyme disease

Ixodes ticks

5

anopheles mosquito behaviors that determine whether they will bite or not

  • Bite dusk to dawn
  • Only females
  • Inactive below 18 degrees C
  • Altitude sensitive
  • Do not like cities

6

Only effective repellents for anopheles mosquito (2)

DEET and picaridin

7

Potential geographical limits of the northern and southern hemispheres for year round survival of Aedes mosquito

January and July Isoforms

8

Why is dengue so important to be aware of?

  • Emerging URBAN VECTOR-BORNE disease (incidence x30 in last 50 yrs)
  • 50 million cases/year
  • 22,000 deaths/year
  • Overtaking malaria as leading cause of fever in returning travellers in several places

9

4 behaviors of Aedes mosquito that determine whether or not they will bite

  • Daytime biters
  • Only females
  • Inactive below 18 degrees C
  • Thrive in cities and elsewhere

10

2 only effective repellents against Aedes mosquito

DEET and picaridin

11

Another measure against Aedes mosquito besides spray-on repellents

Permethrin-treated clothes/nets/curtains

12

Seasonal life cycle of ticks (5)

  • Spring = eggs
  • Summer = larva
  • Spring = Nymph
  • Fall = adults
  • Spring = eggs

13

Seasons that humans are at greatest risk of infection by ticks

Late spring and summer

14

6 body parts to check for ticks

  • In and around the hair
  • Inside belly button
  • Between the legs
  • In and around ears
  • Under the arms
  • Back of the knees

15

Lyme disease risk geographically in Canada (6)

Emerging:

  • Manitoba
  • Ontario
  • Quebec
  • New Brunswick
  • Nova Scotia

Established in southern BC for years

16

Geographic distribution of lyme disease in USA in 2011

Northeast USA

17

One potential reason for dramatically increased incidence of Canadian lyme disease in 2013

"Warmer" winters = favorable for ticks

18

2 ways to avoid direct contact with ticks

  • Avoid wooded and bushy areas with high grass and leaf litter
  • Walk in the center of trails

19

Virus responsible for West Nile virus

Flavivirus

20

Define Flavivirus

ssRNA virus that is a member of Japanese ecephalitis serocomplex, which includes St. Louis encephalitis

21

Former geographical confinement of West Nile virus

  • Initial description in humans in 1937 Uganda
  • Confined to Africa, Middle East and Europe

22

Predominant geographic distribution of WNV in Canada (2002 - 2010)

Predominantly western

23

Year of peak of WNV cases in Canada

2007 (2325 cases)

NOTE: had decreased to 5 in 2010

24

Pyramid of prevention for vector-borne diseases

25

2 less effective repellents against vectors

  • Eucalyptus oil
  • 2% soybean oil

26

5 ineffective repellents against vectors

  • Citronella
  • Ultrasonic devices
  • Ankle/wristbands
  • Geranium oil
  • Baby oil

27

Attractive color for mosquitoes

Dark colors

28

Geographic distribution of falciparum malaria (4)

  • Most of Africa; predominantly west
  • India
  • Southeast Asia
  • Low but present in Amazonian South America

29

Geographic distribution of vivax malaria (7)

  • Central america
  • Amazonian South America
  • East Africa
  • Madagascar
  • South Asia
  • North Kora
  • Southeast Asia