amna: For the first time in 20
years, malaria has been locally
transmitted within the U.S.
The centers for disease control
and prevention has identified
five cases, four in Florida and
one in Texas.
William brangham spoke recently
with an epidemiologist about
what we know and how concerned
we should be.
William: For more on these
unusual cases, we turn to
Catherine Troisi.
She's an infectious disease
epidemiologist with uthealth
Houston school of public health.
Catherine, thank you so much for
being here.
We have seen malaria in the past
in the United States, but these
cases and how they're
transmitting is different.
Can you explain?
Catherine: Sure.
We always, every year, have some
cases of malaria, but they are
in people who acquired the
malaria abroad and then came
back to the United States and
were visiting.
These cases are different
because the people who are
infected got it here in the
United States.
William: And so, is the
hypothesis then that originally
someone got sick abroad, came
back, and then were were bitten
by a mosquito here and that
that's how it spread?
Catherine: Yes.
So someone who got malaria
abroad was came back to the
United States, was bitten, and
then that mosquito bit somebody
else and they got infected.
William: And that is how malaria
spreads.
It's not a person to person
spread, right?
Catherine: Correct.
There has to be a mosquito bite,
although it can be spread
through blood transfusions or
from pregnant mother to the
baby.
William: So when people think of
malaria on some level, I think
people acknowledge all of the
deaths that occur every year all
over the world.
How worrying is this here in the
United States?
Catherine: You know, of course,
public health officials are
keeping an eye on this, but
we're not real worried.
It's not like covid because it's
not spread person to person.
The United States used to,
particularly in southern states,
used to have a lot of malaria.
The precursor to the CDC was
actually formed to combat
malaria in southern states.
However, through the use of
insecticides, through the use of
better sanitation, getting rid
of standing water, informing
people that they should use
insect repellent.
We have been declared malaria
free since 1970.
So while it's disturbing to have
a few locally transmitted cases,
we're just not real worried
about T blowing up into a covid
like situation.
William: I mean, given that
public health success in it is
undoubtedly a success, is there
the concern then that we've sort
of forgotten about malaria and
people don't know what the
symptoms are like and maybe even
doctors may not know what the
symptoms are and may not know it
when they see it.
Catherine: Yeah, we've actually
seen this with a number of
infectious diseases that we've
been very successful in
controlling.
Doctors, parents don't know what
some of these childhood
infections are, and that's
certainly true with malaria.
It's important if someone is
infected to get treated quickly.
For a couple of reasons.
One is for their own health.
But also the longer they are
infected, the more likely it is
the mosquito could bite them and
then transmit the infection to
the United States.
So this is a good wake up call
for physicians particularly and
other health care providers to
look.
Do think malaria, if they see
someone with a high fever and
flu like symptoms.
William: Those are the symptoms,
principally fever, flu like
symptoms?
Catherine: Yeah.
Fever, chills, flu like
symptoms.
William: I understand that this
particular species of parasite,
malaria parasite, isn't as bad.
Is that correct?
Catherine: Well, in one sense,
that is correct.
It does not causes severe
disease as the other strains of
malaria.
But in another sense, it's worse
because the parasite, the
plasmodium parasite can hide
out.
And so you can have what's
called relapsing fever.
So it seems like you're getting
better and then you have
symptoms again.
So it's important for physicians
to be able to tell exactly what
strain you have so that they can
give you.
You may need more medication to
effectively combat it.
William: So if someone felt some
of those symptoms, but then they
went away, maybe not breathe a
sigh of relief and go get that
checked out.
Catherine: Right.
And, you know, those are those
are very in descript symptoms.
So one thing you might think
about is where you are in the
United States.
If you are in Maine, for
example, not very likely that
it's malaria.
If you're in Florida, Texas, you
know those gulf states where
it's very warm, particularly
right now, then maybe you might
be a little bit more concerned.
It also has to do, you know, to
get malaria, you have to be bit
by mosquito.
And so people who are outside a
lot of the time are particularly
at risk.
If you spend most of your time
inside an air conditioning, it's
not so likely.
William: One of the things that
we know that increases the
spread of mosquitoes and
mosquitoes biting us is warmer
temperatures.
We know it's incredibly warm in
the American south right now,
but we also know that climate
change is warming up our
atmosphere and warming up the
planet as well.
Is it is it inevitable that
malaria will eventually come
back to the United States or
not?
Catherine: Well, you are correct
that climate change affects the
distribution of the mosquito
that's responsible for spreading
malaria.
Also, you know, when
temperatures are higher, those
mosquitoes feed more often, so
people are more likely to get
bit and the parasite itself
replicates faster inside T T
mosquito.
Also, climate warming
contributes to increased storms,
so there may be more standing
water where mosquitoes can
breed.
However, again, in the united
States, because we have most
people have screens on their
windows, on their doors, we know
to wear insect repellent,
although this is a good reminder
where we we don't have a lot of
the deficiencies in our
prevention mechanisms that would
lead to wide spread of malaria.
William: All right, Catherine
Tracey of UT health Houston,
thank you so much for being
here.
Catherine: Thank you.