Malaria illness is causing a
lot of economical burden to many household in Nigeria and other African
countries, according to Onwujekwe almost $12 billion annually is consumed by
malaria treatment, it is also said to take 50% of household budget. The African
continent shows the greatest effects of this disease, accounting for more than
90% of DALYs (Disability adjusted life Years) . Although the sequencing of the
genomes of Homo sapiens Plasmodium falciparum and Anopheles gambiense raises
some hope on elucidating the complex molecular mechanism of the disease.
MALARIA INFECTION;
Malaria is due to blood
infection by protozoan parasites of the genus Plasmodium, which are transmitted
from one human to another by female Anopheles mosquitoes. Four species of
malaria parasite infect humans. "Benign tertian" fevers were so named
because they were not associated with the severe and often fatal manifestations
of the "subtertian, malignant" periodic fevers (P. falciparum).
"Tertian" and "quartan" refers to their characteristic
feature of an acute febrile episode, or paroxysm, that returns respectively
every third (P. vivax) or fourth (P. malariae) Today,P. vivax and P. falciparum
are the most commonly encountered malaria parasites. P. vivax is still found
sporadically in some temperate regions, where in the past it was widely
prevalent. It remains, however, very common throughout much of the tropics and
subtropics. Because of the temperature limitations on its transmission by its
mosquitoe vectors, P. falciparum is normally present only in tropical,
subtropical, and warm temperate regions. In the tropics today, P. falciparum
remains widely prevalent. The fourth human malaria parasite is Plasmodium
ovale, which, like P. vivax, is the agent of a tertian malaria and which, also
like P. vivax malaria today, carries a very low risk of fatal outcome. P. ovale
has the most limited distribution of all the malaria parasites of humans. While
it is prevalent throughout most of sub-Saharan Africa, it is otherwise known to
be endemic only in New Guinea and the Philippines (Lysenko A. J. and A. E.
Beljiev e 1969) The malaria parasites enter and leave the body through mosquito
bites, When a mosquito bites a person it sucks up blood. If the person has
malaria, some of the parasites in the blood will be sucked into the mosquito.
Rarely is malaria transmitted through infected needles or blood transfusion.
· The malaria
parasites multiply and develop in the mosquito. After 10-14 days they are
mature and ready to be passed on to someone else.
· If the mosquito now
bites a healthy person, the malaria parasites will enter the body of the
healthy person. The parasites quickly enter the liver and mature into tissue
schizonts.. Subsequently they release thousands of merozoites which invade the
red cells, initiating the erythrocytic phase of the disease. In the red cells they
again transform from ring stage to trophozoites and to schizonts which rupture
and release more parasites to invade more red cells causing the cycles of fever
and chills. Culminating in death or drug treatment. Some of the merozoites
differetiate into gametocytes which can be ingested by a female Anopheline
mosquito subsequently, resulting in an infective sporozoite. In Plasmodim
falciparum, the deadliest of the parasites, the pattern of febrile illness is
not synchronized. Infected erythrocytes are sequestered in microvasculature,
and parasites appear in peripheral blood later in the day (Delley et. al.2002,
Okonkwo et.. al 2004 Unpublished observation)
The symptoms, chronic and acute
effects of malaria
There are chronic and
acute effects from malaria infections. Acute effects include febrile illness
and malaise and in severe cases will include hypoglycaemia, anaemia,
respiratory distress, cerebral malaria and possibly death. Chronic effects
include Anaemia, neurologic and cognitive deficits resulting in poor
development and low school performance in children and poor and erratic
leadership and followership.Indeed, European literature is replete with
description of natives of malarious environments as lazy, irritable, ignorant
unpredictable and prone to maniacal laughter, which probably fueled the
racism of the first European visitors to Africa. Children with hemoglobin
levels less than 11 gram percent (hematocrit < 33%) are at particular risk
and those with hemoglobin levels less than 5 gram percent (hematocrit <
15%) require emergency attention. Crawley J, 2004..draws attention to the
myriad causes and consequences of anemia, particularly iron deficiency and
malarial anemia, and the need for careful monitoring of children for anemia
starting within the first few months of life in areas of intense and stable
malaria transmission; the highest prevalence of anemia occurs toward the end
of the child’s first year. Awareness of common causes of anemia in Nigeria,
such as maternal and childhood nutritional deficiencies (including
micronutrients), intestinal helminths, HIV infection, hemoglobinopathies, and
malaria, is important to manage patients and prevent the acceleration of
severe consequences of, and death from, anemia. The malaria-specific interventions
to prevent anemia are Insecticide Treated nets, chemoprophylaxis, and
intermittent preventive treatment of pregnant women (IPT), and, possibly for
infants (IPTi), and prompt effective treatment of infections. Deworming with
mebendazole and albendazole, treatment of HIV/AIDS, including treatment of
opportunistic infections, and selective use of iron, vitamin A, zinc, and
complementary food supplements should be considered, and attention given to
improved agricultural and eating practices. The negative effects of
co-infection with HIV and malaria during pregnancy have now been shown
definitively by ter Kuile and others 2004 in their review of 11 studies in
Africa.pregnant women infected with HIV had "consistently more
peripheral and placental malaria, higher parasite densities, and more febrile
illnesses, severe anemia, and adverse birth outcomes (low birth weight,
prematurity, intrauterine growth retardation) than HIV-uninfected women,
particularly in multigravidae." Malaria in pregnancy was increased by
5.5% and 18.8% in populations with 10% and 40% HIV prevalence, respectively.
Those pregnant women with malaria had a twofold higher HIV-1 viral
concentration. Less clear is whether malaria increased mother-to-child
transmission of HIV. These investigators urge more research on interactions
between antiretroviral drugs, antimalarials, prophylaxis with cotrimoxazole
for opportunistic infections, and IntermittentPreventiveTherapy, including
attention to anemia and pharmacovigilance, while strengthening prevention
measures for malaria and HIV during pregnancy. The association between
malaria and undernutrition is complex, yet improved nutrition lessens the
severity of malaria episodes and results in a decrease in malaria deaths.
Deficiencies in vitamin A, zinc, iron, folate, and other micronutrients are
responsible for a substantial proportion of malaria morbidity and mortality.
Important evidence is accruing of the long-term neurocognitive impact of
malaria following severe illness. Of 11 well-defined neurocognitive sequelae
following malaria (ataxia, hemiparesis/monoparesis, severe motor deficit,
dysphasia/dysarthria, behavioral difficulties, severe learning difficulties,
visual impairment, hearing impairment, cognitive impairment, language
impairment, and epilepsy), children with epilepsy and motor impairment are
prone to an early death.
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