Mansonella ozzardi is a parasitic nematode found in Central and South America. It has a complex life cycle involving transmission between humans and blackfly or midge vectors. Adult worms live in the body cavities of infected humans, sometimes causing mild symptoms. Diagnosis is made by microscopic identification of microfilariae in blood smears. Treatment involves ivermectin.

1. MANSONELLA
OZZARDI

2. OUTLINE
Introduction
Taxonomic Classification
Morphology
Epidemiology
Life Cycle
Transmission
Manifestation
Laboratory Diagnosis
Treatment and Prevention

3. INTRODUCTION
Mansonella ozzardi is a New
World filaroid parasite
Adults live in the body cavity,
within the mesenteries,
peritoneum, and in
subcutaneous tissues
Infected with Wolbachia
Intermediate hosts are midges
and blackflies

4. TAXONOMIC
CLASSIFICATION
 Kingdom: Animalia
 Phylum: Nematoda
 Class: Secernentea
 Order: Spirurida
 Family: Filariidae
 Genus: Mansonella
 Species: Mansonella
ozzardi

5. MORPHOLOGY
M. ozzardi is a cylindrical and bilaterally symmetrical worm, with
a pseudocoel.
Its exterior, the cuticle, is a protective layer that can withstand
the harsh environment in the digestive tracts of the human hosts.
M. ozzardi and other nematodes have longitudinal muscles that
run along the body wall. They also have dorsal, ventral, and
longitudinal nerve cords connected to these longitudinal muscles.
Adult M. ozzardi are long and slender with reduced lips. Females
are larger than males, and produce thousands of offspring called
microfilariae.

6. MORPHOLOGY
M. ozzardi microfilariae are
170-240 um long, unsheathed,
and have a slender, clear, tapered
tail called a "button hook."
The nuclei do not extend to the
end of the tail.
When stained, the presence or
absence of a sheath, internal
nuclei and organs can all be seen,
with the organization of these
aiding in identification and
classification of the different
filarial worm species.

7. MORPHOLOGY

8. EPIDEMIOLOGY
It is prominent in the subtropical, tropical, and
temperate regions of Central and South America (Mexico,
Panama, Brazil, Colombia, and Argentina), and the
Caribbean
Its prevalence rate varies from a few percent to 96% in
endemic areas such as Trinidad, Guyana, and Columbia

9. LIFE CYCLE

10. TRANSMISSION
M. ozzardi is transmitted by two types of arthropods that feed
on the blood of humans: biting midges (genus Culicoides) and
blackflies (genus Simulium).
Biting midges are small
flies that breed on sandy
beaches near the sea
Blackflies are larger
blood-sucking flies that
breed in fast-flowing
streams and rivers.

11. MANIFESTATION
The pathogenicity of M. ozzardi needs further research.
Although the adult worms live in the body cavities and the
mesentery, they seem to cause little or no harm to their human
hosts.
Infected people rarely present any symptoms. However, a few
clinical manifestations have been reported:1. Moderate fever
2. Coldness in the legs
3. Joint pains, like articular pain or
arthralgias
4. Headaches
5. Pruritus (itchiness)
6. Skin eruptions
7. Pulmonary symptoms
8. Lymphadenitis - inflammation of the
lymph nodes
9. Adenopathy - enlargement of the
lymph nodes
10. Hepatomegaly - enlargement of the
liver

12. LABORATORY DIAGNOSIS
Microscopic examination is the most
practical diagnostic tool used to identify
the M. ozzardi microfilariae in blood
samples from infected patients.
Since the microfilariae are not periodic,
periodicity is not a factor in taking the
blood sample.
Blood smears are usually stained with
haematoxylin and eosin or Giemsa to
visualize the worms under the
microscope.

13. TREATMENT AND
PREVENTIONIvermectin is the treatment of choice for M. ozzardi infections.
Diethylcarbamazine (DEC) also has been used in treating filarial
infections but is not effective in treating M. ozzardi microfilarial
infections.
Individuals living in endemic areas such as the Caribbean should
wear long-sleeved shirts and pants to decrease the exposed body
parts.
Insect repellents could also be used to cover body parts not
protected by clothing.
Communities should also maintain the natural vegetation around
them to decrease the possible breeding grounds for the biting
midges.