Main Highlights-
* What is Zika virus?
* Zika virus first case in Kerala.
* Zika virus deadly for pregnant women?
* Symptoms of Zika virus in pregnant women.
* Treatment of Zika virus.
* Is inflected person again get infection with Zika virus?
* What are the prevention of Zika virus?
All About Zika Virus
Zika virus there's a flavivirus it'san infection that's carried by mosquitoes and it causes an illnessthat's usually very mild it can even be asymptomatic one of the reasons that the virus is up so much concern lately is not from the infection itself but the late consequences particularly in pregnant women so this is what has caused the largest degree of concern congenital abnormalities that have been linked to infection of pregnant women with this virus and that was later effects on the fetus.
In terms of a vaccine we don't have a vaccine for this disease either but there are several candidate vaccines that are in research stages right now and we're hopeful that perhaps within a year or so we'll have some clinical trials on going with vaccines to prevent this disease soJohns Hopkins Medicine we are well positioned to address many aspects of an infectious disease threat like this up I rest for instance at the Bloomberg's chool of Public Health we have many researchers who are doing vaccine development research on similar diseases like dengue and these efforts could berepurposed to develop vaccine.
Note- The World Health Organization currently suggests pregnant women consult their doctor or travel clinic for guidance and recommendations.
There are a lot of viruses out there that can infect humans, but two things that can get really alarming is when a virus spreads quickly and when it causes serious harm. Zika virus has the potential to do both of these things, which is why it’s gotten a lot of attention. Given this, it makes sense to understands bit about Zika virus and the disease it causes. Zika virus is an arbovirus, meaning it’stransmitted via certain arthropods, specifically mosquitos, so it’s a mosquito-borne virus.
Mosquito-borne doesn’t mean that the virus is “born” in the mosquito, though, but it’s “borne”, with an ‘e’, which means carried or transported. Sometimes we call organisms like this “vectors”, where all they do is transport the virus. So with Zika virus, just like other mosquito-borne viruses like dengue fever, yellow fever, Japanese encephalitis, and West Nile virus, the mosquito acts as a vector that transmits the virus from one person to the next. These viruses are all in the genus flavivirus. In order to mature her offspring, female mosquitoes need a blood-meal, which they get from unsuspecting hosts. Mosquitoes find their blood-meals using chemical compounds that we and other organisms give off, like carbon dioxide, ammonia, lactic acid, and octenol. So when a mosquito that also happens to be carrying the virus finds her meal and digs in, the virus infects the human host and starts to multiply or reproduce within the human. With most flaviviruses though, the virus isn’t able to replicate enough in the human host to actually be able to reinfect another mosquito, and so the human is considered a dead-end-host.
However, the Zika virus, along with yellow and dengue fever, is well enough adapted to human hosts such that they can multiply to a point where it can re-infect another unsuspecting mosquito, which can then go on to infect more people. This window lasts for the first week of infection, during which the Zika virus can be found in the blood.So if humans with the disease can transmit back to mosquitoes then you can imagine that areas where there’re a lot of mosquitoes, would be a set-up for spreading the virus super quickly, right? Now the Zika virus is transmitted via mosquitos in the Aedes genus. These blood thirsty little guys can bite at night, but are mostly active during the daytime.
Aedes mosquitoes are also the same ones that transmit Chikungunya fever and dengue fever. When Aedes aegypti or Aedes albopict us, both species of Aedes mosquito,lands on your skin and sticks in it’s long nose—or proboscis, it pierces the epidermis which is the topmost layer, composed almost entirely of keratinocytes. Keratinocytes basically serve to protect against foreign pathogens, and it’s typically pretty good at that.That proboscis though keeps going into the dermis, since the epidermis just gets oxygen from the air and doesn’t have its own blood supply, whereas the dermis does, and thisis what our mosquito’s after, right, the blood meal. Since the proboscis goes through both the epidermal and dermal layers, the cells in those layers are susceptible to infection by Zika virus.
So in addition to keratinocytes, fibroblasts, and dendritic cells have also been found to be permissive to Zika virus, meaning they have some sort of receptor or attachment site that basically says, here you go man, come on in.
Now we still don’t know everything about the Zika virus infection, but we do know that when it enters the cell, it injects a single-stranded positive RNA strand. Positive means that this piece of RNA’s a lot like our own mRNA;it’s basically ready to rock and get translated into proteins. The virus’s genome is translated by our own cellular machinery into more viruses.
Eventually those cells-turned-virus-making-factories die, which actually ends up releasing more viruses to infect more cells. As bleak as all that sounds, our immune system’sactually pretty good at fighting off Zika virus, and only 1 in 5 get sick from infection, and the often the others won’t even notice they’ve been infected.
Common symptoms
when patients have them, are mild fever and skin rash, but some also experience muscle and joint pain, headaches, and conjunctivitis, or red eyes. The incubation period, or time from infection to symptoms isn’t known, but it’s thought to be from a few days toa week.
Treatment
usually just involves treating the symptoms, things like getting plenty of rest, drinking fluids to prevent dehydration, and taking medicine like acetaminophen to help reduce pain and fever. Okay so we’ve hit the “spreads quickly”part, which really matters most in places with lots of mosquitoes, but what about the“causes serious harm” part?
Well, although it causes mild symptoms in adults, there’smore to the story. In October 2015, in areas of Brazil where Zika virus has been circulated quite a bit, public health officials noticed a significant increase in babies born with microcephaly, which is when a child is born with an abnormally small head and therefore abnormally small brain size; this has the tendency to cause serious neurological and intellectual deficits, seizures, as well as vision or hearing problems. It was noticed that there was a huge increase in babies with microcephaly—up to a 20-fold increase—among Brazilian states with Zika virus outbreak.
As of November 2015, the European Center for Disease Control has stated that it’s plausible the Zika virus is able to cause microcephaly in the developing fetus or newborn, as the Zika virus can be transmitted from mother to baby during pregnancy or around the time of birth, although it’s not yet known how often this happens or how exactly the Zika virus is linked to microcephaly. In addition to being spread mostly by mosquito bites, and in some cases from mother to child, Zika virus has also been reported to spread through both blood transfusions and sexual contact.
Precautions
Currently, there’s no vaccine for Zika virus,so it’s highly advised to take precautions when traveling to areas of outbreak, mostly limiting mosquito bites, so doing things like wearing bug spray all day, or wearing long-sleeve shirts and pants, especially during the day when the Aedes mosquitoes are most active.
If infected, it’s especially important to avoid mosquitoes to avoid spreading Zika virus to others, especially in that first week of symptoms.