Vector Control Flashcards
• Carrier of disease agents from one organism to another
Vector
*along with agent and environment
Presence of vectors result to what
higher discomfort, lower productivity, and eventually, death.
(see table of Major vector-borne diseases of human and associated etiological agents and arthropod vectors)
(see table of Major vector-borne diseases of human and associated etiological agents and arthropod vectors)
Type of vector serving as external carrier such as housefly carrying enteric organisms or Aedes spp. transmitting Dengue
Mechanical
T or F: mechanical vectors are not involved in life cycle of infectious agent
true
type of Vector which is PART of the life cycle of the infectious agent
Biological
Reservoir of the infectious agent
Factors affecting vector-borne diseases
- Population Migration
- International Travel and Commerce
- Land Use Change
- Microbial Adaptation and Resistance (drug resistance)
- Lack of Reliable Public Infrastructure Services
- Climate Change
[Factors affecting vector-borne diseases] What influences population migration?
war, environmental degradation, and regional conflicts
[Factors affecting vector-borne diseases] Aspect of population migration which increases access to habitats of vectors (i.e.: open sewers, water storage containers)
Rapid unchecked urbanization
[Factors affecting vector-borne diseases] Aspect of population migration which causes disease vectors to develop a preference for feeding solely on humans
Higher population density
[Factors affecting vector-borne diseases] This factor ensures the continual spread of disease vectors
International Travel and Commerce
• Seaports, airports and cemeteries are especially vulnerable
• The effects of global trade in food result in unhygienic food
production, handling and preparation
[Factors affecting vector-borne diseases] How do changes in land and water patterns such as deforestation affect disease vectors?
Additional breeding habitats due to water management practices (e.g. dam building, open irrigation canals & flooded rice fields, open sewer pits)
[Factors affecting vector-borne diseases] Lack of reliable public infrastructure services include
Lack of funds for sanitation, effective water management systems, and basic public health care
three factors which drive vector-borne diseases
Zoogeography (natural distribution of vector species)
Climate (major)
Man-made drivers
Man-made drivers of vector-borne diseases
modulate the distribution and include climate change, hydrological changes/irrigation dams, changed land use patterns and urbanization
Examples of vectors
A. Mosquitoes B. Flies C. Cockroaches D. Bedbugs E. Lice F. Rodents
T or F: It is important to know which type of mosquito is present to determine prevention and control of possible spread of disease and infection
true
Four stages of development of mosquitoes and flies
Egg
Larva
Pupa
Adult
During which stage of mosquito development that female mosquitoes require blood meal
in production of eggs
- to obtain protein in hemoglobin for laying eggs in water
- fertilized eggs require water for hatching
Stage of mosquito development wherein full grown larva does not feed and spends most of its time at the water surface
pupa
Stage of mosquito development wherein Anopheles larvae lie parallel to the water surface
Larva
® Culicine larvae hang at 450 angle to the water surface
Durng this stage, female mosquitoes bite and are usually the vector
adult
*males feed on plant juices
This is the basis of comparison between different types of mosquitoes
Biting Patterns and Preferred Habitats of Mosquitoes
subject to change with climate change
Biting Patterns and Preferred Habitats of ANOPHELES SP.
Biting patterns: Daytime Preferred habitats: Permanent water, partially shaded, clean running water Disease Importance: Malaria, Eastern US, Africa, Asia
Biting Patterns and Preferred Habitats of AEDES AEGYPTI
BP: Mainly daytime can bite at night (welllit areas)
PH: Artificial containers, clean stagnant water, indoors
DI: Yellow Fever, Dengue
Biting Patterns and Preferred Habitats of Culex sp.
BP: Night time
PH: Permanent, dirty water, indoors, outdoors
DI: Encephalitis, US
What are transmitted by the mosquito vector (Anopheles minimus flavirostris) in malaria?
plasmodium parasites
How many provinces in the Philippines are endemic of malaria?
80
- 22 are malaria free but latest data indicate that 27 provinces are now free
- 59 still with cases
- 7 with high number of cases
9th leading cause of morbidity in PH
Malaria
14 million at risk
Region with highest prevalenc of malaria
region iv-b (82%)
2nd: region xi
* 77% of reported cases from Palawan followed by Davao del Norte (7%) and Sultan Kudarat (6%)
Malarial parasite sp with widest distribution and cycle every 48 hours with common relapses
P. vivax
*P. falciparum and ovale also cycle every 48 hours
Characteristics of P. falciparum
• Most common in the Philippines; in tropical and subtropical regions • Causes cerebral malaria • rare relapses
Plasmodium which cycles every 72 hours and is widely distributed producing persistent infection
P. malariae
P. ovale is a rare species in?
africa and asia
(see table 4. Geographic distribution of Malaria in the Philippines)
(see table 4. Geographic distribution of Malaria in the Philippines)
Dengue, which usually occur only during the rainy season, but is now perennial throughout the year, and a major health problem in Asia-Pacific is caused by?
arbovirus
*transmitted by A. aegypti (day biting and also late afternoon)
producer of dengue vaccine (tetravalent; contains serotypes 1-4) in PH
Sanofi Pasteur
*for 9-45 y.o.
Serotypes of dengue common in PH
2 and 4