TUNGIASIS- A neglected parasitic infestation
A
skin infestation caused by burrowing flea named T. penetrans belongs to order Siphonaptera. It is an Infectious disease. Tungiasis is
an inflammatory skin disease found in the tropical parts of Africa, the
Caribbean, Central and South America, and India. Lesions
caused by this are characterized by a white patch with a black dot in the center. The
infestation of Tungiasis can rapidly affect an entire home,
school or community. The flea is highly contagious and is
difficult to eradicate. Children that are infected become outcasts because of
the shame associated with this disease. They cannot run, play, or concentrate
in class because of the pain.
Jiggers are easily transmitted among the
poor living in urban slums and rural societies. It is endemic in developing
countries in the tropics, mainly in the resource-poor people of South America,
the Caribbean and subsaharan Africa. The disease only periodically affects
travelers to endemic regions in South America and Africa; however persons
living in native communities commonly suffer from serious infestation. In
tropical regions, Tungiasis caused
by T. penetrans is a human disease
directly linked to the parasitism of humans by fleas. Though, to many of the
general population, the insidious attacks by fleas on people and domestic
animal causes irritation, blood loss, and severe discomfort are equally
important as disease threat. The aim of this paper was to review the existing
literature concerning Tungiasis.
Epidemiology of the disease:
Tungiasis is present globally in more than 88
countries with varying degrees of incidence and prevalence. Flea-borne
infections are emerging or re-emerging throughout the world, and their
incidence is on the rise. This parasitic disease is of special community health
concern in extremely prevalent regions such as Nigeria, Kenya, Cameroon,
Trinidad, Tobago, and Brazil, where its prevalence, mostly in poor peoples, has
been recognized to reach 50%. T.
penetrans is distributed in tropical and subtropical regions of the world,
including Mexico to South America, the West Indies and Africa. The fleas
normally occur in sandy climates, including beaches, stables and farms.
Biology and transmission of
intriguing parasite:
The
off-host part of the sand flea cycle is similar to other Siphonaptera species.
Expelled eggs fall to the ground and develop into larvae, pupae, and adults in
the immediate surroundings. Larvae hatch after 1 to 6 days (mean 3–4 days) and
pupation takes place after another 5–7 days. The formation of adult fleas
inside the puparium needs 9–15 days. Under favorable conditions, an adult sand
flea will emerge about 20 days after an egg has “touched down”.
Three
life cycles of the sand flea coexist in a tropical environment: a human, a
domestic animal, and a sylvatic cycle. These cycles overlap, partially or
totally.
T. penetrans
is one of the few parasites that can maintain its whole life cycle in a
person's sleeping quarter. Eggs expelled when a person sleeps will fall
directly down to the floor or fall later, when the bed is made. The eggs may
then be transferred to crevices and holes when the floor is swept. The larvae
feed on the ever-present organic material. Eventually, adults emerging from
pupae adhere to and penetrate into the skin, when a person places his or her
naked feet on the ground. If people have to sleep on the floor, sand fleas will
also penetrate parts of the body other than the feet.
Clinical Findings:
The
initial burrowing by the gravid females is usually painless; symptoms,
including itching and irritation, usually start to develop as the females become
fully developed into an engorged state. Inflammation and ulceration may become
severe, and multiple lesions in the feet can lead to difficulty in walking.
Secondary bacterial infections, including tetanus and gangrene, are not
uncommon with Tungiasis. The initial
sign of infestation by jigger flea is a minute black lesion on the skin at the
site of entrance. The zone around the entrenched flea develops very irritating
swelling leading to ulcerations, lymphangitis, and formation of pus. When the
female fleas die, they rest embedded inside the host, repeatedly causing
swelling and consequently secondary infections. If unnoticed, it leads to
gangrene, auto-amputation of fingers, damage of toes, tetanus, or death.
Lack of self-confidence:
The parasite causes pain and injury that can
seriously impede activities and performance of many of life’s chores, making a
person dependent on others. The ulcerations and auto amputation of the digits
make the victims feel embarrassed of being in public places and may usually
reduce their self-confidence.
Prevention and control:
Prevention
approaches include, wearing closed shoes; keeping animals contained; wetting
the floors within houses regularly; maintaining good personal hygiene. Daily
check of the feet with immediate extraction of embedded fleas and subsequent
disinfections of the lesion protect against complications. Administering
antibiotics and applying insecticide will minimize the occurrence and impact of
T. penetrans and secondary microbial
complications.
Treatment:
Mechanical
extraction of flea by using sterile needle after cleaning area with antiseptic
solution.
Disease perception and health
seeking behavior:
Communities suffering from Tungiasis do not recognize Tungiasis
as an important health threat, even with severe disease present in the many of
the children. In fact, mothers rarely take children with overt lesions to
primary health care centers; they seem to be ashamed because the presence of
multiple Tungiasis lesions would
indicate that they do not sufficiently care for their children. Physicians’
awareness of the disease is also deficient. As fleas are normally removed by
the patient or a caretaker, and lesions are not brought to the attention of
medical professionals, physicians consider Tungiasis
to be nuisance rather than an important infection. Moreover, when complications
arise at a later stage, this is seldom attributed to T. penetrans.
Conclusion:
The
presence of the jigger in the skin causes itching feeling, and in severe cases
causes damage of nails, formation of ulcers, inflammation, suppuration, chronic
lymphedema, sepsis and could be death. Jigger infestation affects the education
of teenagers as they might be incapable to walk to school, join in regular learning
activities. The ulcerations of the fingers due to severe Tungiasis make the sufferers feel ashamed of being in social places
and it usually reduces people’s self-confidence. Jiggers infestation is likely
to be increasing and causing livelihood of communities in developing countries.
Therefore, new appropriate prevention and control approaches should be designed
to mitigate the persistence of the disease (Tungiasis), particularly in vulnerable and poor communities.
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