Malaria and children: Progress in intervention coverage - Unicef

8
Background on malaria
Where is the burden of
malaria greatest?
Sub-Saharan Africa is the region
hardest hit by malaria. Most of sub-
Saharan Africa comprises highly
endemic areas of stable malaria
transmission where infection is
common and the population can
develop some immunity. In these
areas children and pregnant women
are most at risk of developing severe
symptoms or dying from malaria
infection. In areas of low, epidemic
or unstable malaria transmission,
such as highlands and desert
fringes, few people have built up
natural immunity and thus adults
are also at risk of becoming seriously
ill with malaria.
What causes malaria?
Malaria is caused by parasites that
are transmitted by infected mosquitoes
that most often bite at night.
The malaria parasites enter the
human bloodstream through the
bite of an infected female Anopheles
mosquito. Of the four malaria parasites
that affect humans, Plasmodium
falciparum is the most common in
Africa—and the most deadly.
Why are African children
and pregnant women
the most vulnerable?
Children under age five are most
likely to suffer from the severe
effects of malaria because they have
not developed sufficient naturally
acquired immunity to the parasite.
A severe infection can kill a child
within hours (see figure).
Malaria during pregnancy can
range from an asymptomatic infection
to a severe life-threatening
illness depending on the epidemiological
setting. In areas of stable
malaria transmission most adult
women have developed enough
natural immunity that infection
does not usually result in symptoms,
even during pregnancy. In such
areas the main impact of malaria
infection is malaria-related anaemia
in the mother and the presence of
parasites in the placenta, contributing
to low birthweight, a leading
cause of impaired development and
infant mortality. In areas of unstable
malaria transmission women
have acquired little immunity and
are thus at risk of severe malaria
and death.
How is malaria diagnosed?
Prompt and accurate diagnosis is a
key component of effective disease
management. The ‘gold standard’
is parasitological diagnosis through
microscopic examination of blood
smears, although rapid diagnostic
tests are a new technology whose
use is growing.
In high and moderate malaria transmission
areas where infection is
common, the World Health Organization
recommends that all children
under age five with fever be treated
with antimalarial medicines based
on a clinical diagnosis—or in other
words, at the signs and symptoms of
the disease. Although parasitological
diagnosis is recommended for
older children and adults, in the
resource-poor settings common in
malaria-endemic areas the majority
of malaria diagnoses in all age
groups remains clinical. 1 Furthermore,
even in unstable transmission
areas where parasitological
What are the symptoms
of malaria?
Malaria typically results in flulike
symptoms that appear 9–14
days after an infectious mosquito
bite. Initial symptoms can include
headache, fatigue and aches in the
muscles and joints, fever, chills,
vomiting and diarrhoea; they can
quickly progress into severe disease
and death. Among young children
fever is the most common symptom
of malaria.
Malaria kills children in three ways
Infection in
pregnancy
Low birthweight
Preterm delivery
Source: WHO and UNICEF 2003a.
Acute febrile
illness
Cerebral malaria
Respiratory distress
Hypoglycaemia
Death
Chronic repeated
infection
Severe anaemia