Arthropods of Medical Importance
Arthropods of Medical Importance
Arthropods of Medical Importance
Arthropods as Vectors
Kingdom: Animalia
Phylum: Arthropoda
(exoskeleton, jointed legs)
Class: Insecta (6 legs)
Lice, fleas,
mosquitoes
Class: Arachnida (8 legs)
Mites and ticks
May transmit diseases
(vectors)
Copyright 2004 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 12.31, 32
Arthropods as Vectors
Figure 12.33
Class
Order
Vector
Disease
Arachnida
Dermacentor
(tick)
Ixodes (tick)
Ornithodorus
(tick)
Relapsing fever
Class
Insecta
Order
Sucking lice
Fleas
True flies
True bugs
Vector
Disease
Pediculus
(human louse)
Xenopsylla (rat
flea)
Chrysops (deer
fly)
Aedes
(mosquito)
Anopheles(mosq
uito)
Culex
(mosquito)
Glossina (tsetse
fly)
Epidemic typhus
Triatoma
(kissing bug)
Chagas disease
Emdemimurine typhus
Tularemia
Dengue fever, yellow fever
Malaria
Arboviral encephalitis
African trypanosomiasis
Lyme Disease
The bacteria are inoculated into the skin by a tick bite, from ticks of
the genus Ixodes.
Lyme Disease
Multiple lesions of erythema
migrans occur in approximately
20% of patients. A carpenter from
Nantucket who worked
predominantly outside had been
treated with Lotrisone for 1 week
before presenting to the
emergency department with the
rashes seen in this photo. The
patient had no fever and only mild
systemic symptoms. He was
treated with a 3-week course of
oral antibiotics
Pediculosis
Pediculosis
Headlicearewinglessinsectsspendingtheirentirelifeon
humanscalpandfeedingexclusivelyonhumanblood.
Dengue Fever
also known as breakbone
fever, is an infectious tropical
disease caused by the dengue
virus. Symptoms
include fever, headache, muscl
e and joint pains, and a
characteristic skin rash that
is similar to measles.
Dengue is transmitted by
several species
of mosquito within the genus
Aedes, principally A. aegypti.
Prevention
Classification:
Phylum Apicomplexa
Class Sporozoea
Coccidia
Subclass
4 species infecting
humans:
Plasmodium
falciparum
Plasmodium vivax
Plasmodium ovale
Plasmodium
Feeding female
Anopheles
Exflagellation showing
microgametes
Copyright
2004 Pearson Education, Inc., publishing as Benjamin Cummings
Schizont
multinucleate form in
rbc
Trophozoite
Copyright 2004 Pearson Education, Inc., publishing as Benjamin Cummings
Gametocyte
Clinical Manifestations:
Malarial Paroxysm
P. falciparum
P. vivax
P. ovale
P. malariae
Clinical
Presentation
Malignant
tertian
Benign tertian
Benign tertian
Quartan
Length of
asexual cycle
48 hrs or less
48 hrs
48 hrs
72 hrs
Infected RBC
size and
presence of
cytoplasmic
granules
Normal
Enlarged
Enlarged
Normal
Maurers dots
Trophozoites
Small, more
solid rings
Small, more
solid rings with
narrow band
across the cell
# of merozoites
8-24, smaller
than other spp
4-12, forms a
rosette-like
structure
6-12, forms a
rosette-like
structure
Gametocyte
Round, small
Round,
compact
12-24 in 1-2
clumps, almost
fills the cell
Zeimmans dots
Severe malaria:
Anemia, anoxia, pulmonary edema, anuria,
black water fever, cerebral malaria
Diagnosis:
Treatment:
Chloroquine-Sulfadoxinepyrimethamine
Prevention:
Vector control
Personal protection
against mosquitoes
Trypanosoma cruzi
Causes American
Trypanosomiasis or
Chagas disease.
Trypanosoma cruzi
.
VECTOR family Reduviidae
- genera Triatoma
- common names: assassin
bug, kissing bug,
MEGACOL
ON
Treatme
nt:
No acceptable treatment
Nifurtimox and benznidazole partially
effective in acute cases
ThankYou!