by Rishen Afakpo J. J.
Soil-transmitted
helminths infections are among the most common infections worldwide and affect
the poorest and most deprived communities. And they are also considered as
Negleted Tropical Diseases, NTDs. This include; Roundworms (Ascaris lumbricoides), Whipworm (Trichuris trichiura), Hookworm (Necator americanus and Ancylostoma duodenale) and Strongyloides stercoralis. They are
transmitted by eggs that are passed in the faeces of infected people. Adult worm
live in the intestine where the produce thousands of eggs each day. In areas
that lack adequate sanitation, these eggs contaminate the soil. This can happen
in several ways;
1. If infected person defecate outside
(near bushes, in a garden or field) or if faeces of an infected person are used
as fertilizer, eggs are deposited on soil.
2. Eggs that are attached to vegetables
or fruits are ingested when the vegetables or fruits are not carefully cooked
or peeled.
3. Eggs are ingested from contaminated
water sources. This can happen through surface run-off rain water that washed
the eggs in the soil and deposited in the water sources eg open well-water,
lakes, sea, rivers, streams, ponds etc
4. Eggs are ingested by children who
plays in the contaminated soil and then put their hands in their mouth without
washing them.
5. And through long fingernails that are
not properly taking care of.
Ascaris lumbricoides removed from African child intestine
No direct person-to-person infection transmission or
infection from fresh faeces, because eggs passed in faeces need almost three(3)
weeks to mature in the soil before they become infective.
Hookworms and Strongyloides
stercoralis eggs hatch in the soil releasing larvae that mature into a form
that can easily penetrates the skin. People become infected with hookworms and Strongyloides stercoralis primarily by
walking barefoot on the contaminated soil or beaches.
Whipworm (Trichuris trichiura)
More than 1.5 billion people or 24% of the world population
are infected with soil-transmitted helminths infections worldwide. Infections are
widely distributed in tropical and subtropical areas, with the greatest number
occurring in sub-saharan Africas, the Americas, China and Asia. Over 270 million
pre-school age children and over 600 million school age children lives in areas
where these parasites are intensively transmitted and are in need of treatment
and preventive intervention. WHO, 2017.
According to Centre for Disease Control and prevention, CDC
report 2017; approximately 807-1,121 million people are infected with
Ascariasis, approximately 604-795 million of people are infected with
Trichuriasis, approximately 576-740 million of people are infected with
Hookworms and Strongyloidiasis worldwide.
Hookworms
NUTRITIONAL EFFECTS
Soil-transmitted helminths impair the nutritional status of
the people the infect in multiple ways;
1. The worms feed on host tissues,
including blood, which leads to a loss of iron and protein, which eventually
causes Anaemia.
2. The worms increases malabsorption of
micronutrients needed by the body. In addition, Roundworms may possibly compete
for vitamin A in the intestine of its host.
3. Some soil-transmitted helminths also
cause loss of appetite and therefore, a reduction of nutritional intakes and
physical fitness. In particular, T.
trichiura can cause diarrhea and dysentery.
4. Their infection can also lead to
complications including ileus, that require surgical intervention.
Strongyloides stercoralis
CONTROL AND PREVENTION
a. Avoiding any and all contact with earth
contaminated with human waste, especially faeces.
b. Thoroughly washing hands with soap
before handling food, especially when you come in contact with contaminated
soil.
c. Communicating to children the
importance of washing hands as a means to prevent infection.
d. Health and hygiene education in our
primary and secondary schools.
e. Washing, peeling and/or cooking all
vegetables and fruits before consumption, especially in a case where they
vegetables or fruits was grown in soil fertilized with manure.
f. No defecating outdoors; using toilets
connected to effective sewage disposal systems.
g. Where possible,it is recommended that
people in at-risk communities refrain from walking barefoot in areas where
hookworms and Strongyloidiasis is prevalent and by all means avoid ingestion
and playing in a dirt beaches soil.
h. Provision of adequate sanitation is
also important, but not always possible in resource-poor settings.
i.
Water
supply sources should be well-protected from surface run-off water during rainfall.
j. Cutting down-low your fingernails if
you cant take good care of it.
k. Periodic deworming with effective
medicine; consult your doctor for advice on effective Anthelminthiasis
medicines.
