Plasmodium vivax
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Plasmodium
vivax
Kingdom: Protista Phylum: Apicomplexa Class: Aconoidasida Order: Haemosporida Family: Plasmodiidae Genus: Plasmodium Species: P. vivax
The
parasite
Plasmodium
vivax is
the most
frequent
and
widely
distributed
cause of
benign,
but
recurring
(tertian),
malaria.
It is
one of
four
species
of
parasite
that
commonly
cause
malaria
infection
in
humans.
It is
less
virulent
than
Plasmodium
falciparum,
the
deadliest
of the
four,
and
seldom
fatal.
P. vivax
is
passed
on by
the
female
Anopheles
mosquito,
since it
is the
only
gender
that
bites.
Asexual
forms:
Immature
trophozoites
(Ring or
signet-ring
shaped),
about
1/3 of
the
diameter
of a
RBC.
Mature
trophozoites:
Very
irregular
and
delicate
(described
as
amoeboid);
many
pseudopodial
processes
seen.
Presence
of fine
grains
of brown
pigment
(malarial
pigment)
or
hematin
probably
derived
from the
haemoglobin
of the
infected
red
blood
cell.
Schizonts
(also
called
meronts):
As large
as a
normal
red
cell;
thus the
parasitized
corpuslce
becomes
distended
and
larger
than
normal.
there
are
about
sixteen
merozoites.
Sexual
forms:
Gametocytes:
Round.
The
gametocytes
of P.
vivax
are
commonly
found in
the
peripheral
blood at
about
the end
of the
first
week of
parasitemia.
Microscopically,
the
parasitised
red
blood
cell is
up to
twice as
large as
a normal
cell and
fine
pink
Schüffner's
stippling
are seen
on the
cell's
surface.
The
parasite
within
it is
often
wildly
irregular
in shape
(described
as
"amoeboid").
Schizonts
of P.
vivax
have up
to
twenty
merozoites
within
them. It
is rare
to see
cells
with
more
than one
parasite
within
them.
Merozoites
will
only
attach
to
immature
blood
cell
(reticulocytes)
and
therefore
it is
unusual
to see
more
than 3%
of all
circulating
erythrocytes
parasitised.
P. vivax
and P.
ovale
that has
been
sitting
in EDTA
for more
than
half-an-hour
before
the
blood
film is
made
will
look
very
similar
in
appearance
to P.
malariae,
which is
an
important
reason
to warn
the
laboratory
immediately
when the
blood
sample
is drawn
so they
can
process
the
sample
as soon
as it
arrives.
Blood
films
are
preferably
must be
made
within
half-an-hour
of the
blood
being
drawn
and must
certainly
be made
within
an hour
of the
blood
being
drawn.
The
incubation
period
for the
infection
usually
ranges
from ten
to
seventeen
days and
sometimes
up to a
year.
Persistent
liver
stages
allow
relapse
up to
five
years
after
elimination
of red
blood
cell
stages
and
clinical
cure.
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Kumkum / safron - Crocus sativus
Crocuses belong to the family Iridaceae. The saffron crocus is classified as Crocus sativus, It is a shrub. Leaves are seen towards the base of the stem and are compactly arranged.Read More about safron.....
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