welcome to another MedCram lecture we're going to talk about the Zika virus
this has been a big issue in the news what is the Zika virus what kind of
symptoms does it cause why is it important what are the consequences
what's the diagnosis and how to treat it we're gonna talk about all of those
issues with Zika so what is Zika it's a virus that is transmitted via mosquitoes
and it's particularly a big deal right now in the Central American Americas
Caribbean area you should know that it's a RNA virus and so in that sense it's
just like dengue it's just like yellow fever at West Nile okay all of these are
viruses that are transmitted by mosquitoes in that sense and
specifically it's the ADEs mosquito which means that you've got to be aware
of this in the daytime because that's when that mosquito feeds it feeds in the
daytime so it's an RNA virus and as a result of that it uses reverse
transcriptase and that is very similar to the HIV virus so why is this a big
deal well they can find this virus in blood in urine and semen saliva in
cerebral spinal fluid in breast milk and in amniotic fluid so the w-h-o recently
said that this was a spreading explosively in the area of Central
America northern part of South America and also the southern part of North
America so the question is is well what happens
when you're bit by an infected mosquito well if you were to take everybody who
was bit by a mosquito who was infected with the Zika virus only about 20% of
them would actually get symptoms the others would not get any symptoms so the
reason why this is becoming big in the news is for three major reasons number
one it's exploding there seems to be an outbreak in other words number two it's
happening at just the wrong time because as we're giving this lecture right now
this is 2016 and the Olympics are coming to Brazil which is where this is so
Olympics and specifically Brazil but the third thing is and this won't change
after the Olympics or Brazil is that one of the most feared complications of this
virus even though hardly anybody ever dies from it is if a pregnant woman is
exposed to this virus and indeed contracts it there is a concern for
birth defects specifically something called microcephaly that's a small head
basically and it can cause mental retardation etc specifically and
exceptionally if the infection occurs in the first trimester that's when the
greatest risk is of course that's when the head is developing so if you're bit
you've got about a 20% chance of getting symptoms so what are those symptoms the
big symptoms that you should look out for is a low-grade fever
that's very nonspecific but the key there is low-grade fever the other one
is a maculopapular rash okay another one is our thrall jizz that means a pain in
your joints so arthralgias specifically the small joints like the hand the small
joints of the hands another thing that you'll see is conjunctivitis so
basically red eyes okay but not pure uhland so that that would be bad
Tyrael but conjunctivitis the other thing that we see in terms of birth
defects is something else there's a fourth one
and it's it's kind of questionable but it's just something called Dionne bere
syndrome where people become paralyzed from their feet up and eventually can't
breathe so what are the symptoms that you'll see if we were to take a hundred
people that got bit by this mosquito that had the virus and they were
actually going to contract the virus 80% of them might not even have symptoms but
20% would and they are again low-grade fevers maculopapular rash arthralgias
especially in the small joints and conjunctivitis the reason why this is a
big issue right now that you'll see it is because there's a lot of people that
are coming down with this virus in the Caribbean and in the in Puerto Rico US
Virgin Islands and in Brazil and Venezuela also because a lot of people
from all over the world are going to be flocking to that area of the country a
lot of them of childbearing age and they're going to want to know whether or
not it's worth the risk and what is the risk birth defects specifically
microcephaly which has been associated with this virus so what are the other
things that this could be we've talked about the fact that it's contracted from
a mosquito so the big things or the differential diagnosis that you've got
to be concerned about is of course dengue fever which is also spread by a
mosquito however the thing about dengue fever is is that it gives you a high
fever not a low-grade fever but at high fever also there is muscle pain
associated with this which is different from our ouches and the other thing is
that you will not see conjunctivitis the other thing that you've got to be
concerned about in terms of the differential diagnosis is a condition
called chikungunya which has nothing to do with the animals of chickens per se
but chikungunya also has high fever associated with it but instead of small
joints like as in Zika virus you're going to have large
joints in fact these people sometimes can't even walk straight and it's
actually debilitating having this so how do you make this diagnosis to make the
way you make the diagnosis for dengue fever is with serology what does that
mean that means you're looking for antibodies against the virus
same thing for chikungunya user you're looking for antibodies against the virus
okay that's how you can tell that it's not Zika virus so how can you tell if
it's Zika virus so what is the diagnosis of Zika if your healthcare provider and
you want to know well there's two phases there's an early phase and there's a
late phase and the early phase is basically anything from zero to seven
days and beyond that is seven plus days and the reason why there's two phases is
because early on you have the virus in the blood spreading around and so that's
the best way to make the diagnosis because the body has not yet made fully
antibodies against that virus however later on the body would have made
antibodies so in the early phase this is based on virus detection so as a result
of that you're going to use PCR specifically you're going to use reverse
transcriptase PCR because again this is an RNA virus so you want to do it that
way now sometimes the virus goes away quickly or is not there and so if the
result is negative that can't rule it out but if it's positive that rules it
in from seven days plus you're going to be looking at antibodies so again you're
gonna be looking at serology and here you could be looking at Zika virus I g-m
remember IgM is the antibody that goes up first in an acute infection and then
G takes over and you're going to want to make sure because there's a lot of cross
reactivity between Zika antibody and let's say dengue antibody that the Zika
antibody IgM is higher at least four times higher than the dengue fever IgM
if it's not at least four times higher than the diagnosis is question of
and if you don't have access to this you can always ask for the CDC or the Public
Health depending on which county in the United States you live or if you're
living outside the United States the w-h-o so what about the treatment what
about the treatment for Zika well it's supportive just like most viruses you
just need to support them make sure they're well hydrated make sure they're
not dehydrated make sure they don't go into renal failure but because of the
fact that there could be some issues with bleeding you want to use tylenol
instead of aspirin so you don't want to use aspirin because aspirin can increase
the risk of bleeding there is no absolute cure for Zika virus and there
is no vaccination if you are pregnant and you get infected with the Zika virus
you probably want to go and get professional help in terms of obstetrics
and gynecology and this could involve ultra sonography and serial
ultrasonographer of the fetus to make sure that it doesn't develop
microcephaly and if it does then further evaluation can be performed at that
point so I hope this helps with your understanding of Zika virus thanks for
joining us
you