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Zika outbreak: What you need to know Zika outbreak: What you need to know
(5 days later)
The Zika virus, an alarming and disturbing infection that may be linked to thousands of babies being born with underdeveloped brains, is spreading through the Americas. The World Health Organization has declared the Zika virus a global public health emergency.
The alarming and disturbing infection, which may be linked to thousands of babies being born with underdeveloped brains, is spreading through the Americas.
Some areas have declared a state of emergency, doctors have described it as "a pandemic in progress" and some are even advising women in affected countries to delay getting pregnant.Some areas have declared a state of emergency, doctors have described it as "a pandemic in progress" and some are even advising women in affected countries to delay getting pregnant.
Why is it a public health emergency?
Declaring Zika as a "public health emergency of international concern" singles the disease out as a serious global threat. It puts it in the same category of importance as Ebola. This should spark an international drive to invest more money and resources into delivering aid and finding a treatment or a vaccine to stop the virus.
The World Health Organization is worried that Zika is spreading far and fast, with devastating consequences.
What are the symptoms?What are the symptoms?
Deaths are rare and only one in five people infected is thought to develop symptoms.Deaths are rare and only one in five people infected is thought to develop symptoms.
These include:These include:
A rare nervous system disorder, Guillain-Barre syndrome, that can cause temporary paralysis has been linked to the infection.A rare nervous system disorder, Guillain-Barre syndrome, that can cause temporary paralysis has been linked to the infection.
There is no vaccine or drug treatment. Patients are advised to rest and drink plenty of fluids.There is no vaccine or drug treatment. Patients are advised to rest and drink plenty of fluids.
But the biggest concern is the impact it could have on babies developing in the womb and the surge in microcephaly.But the biggest concern is the impact it could have on babies developing in the womb and the surge in microcephaly.
What is microcephaly?What is microcephaly?
It is when a baby is born with an abnormally small head, as their brain has not developed properly.It is when a baby is born with an abnormally small head, as their brain has not developed properly.
The severity varies, but it can be deadly if the brain is so underdeveloped that it cannot regulate the functions vital to life.The severity varies, but it can be deadly if the brain is so underdeveloped that it cannot regulate the functions vital to life.
Children that do survive face intellectual disability and development delays.Children that do survive face intellectual disability and development delays.
It can be caused by infections such as rubella, substance abuse during pregnancy or genetic abnormalities.It can be caused by infections such as rubella, substance abuse during pregnancy or genetic abnormalities.
Brazil had fewer than 150 cases of microcephaly in the whole of 2014, but there have been more than 3,500 reported cases since October.Brazil had fewer than 150 cases of microcephaly in the whole of 2014, but there have been more than 3,500 reported cases since October.
The link with Zika has not been confirmed.The link with Zika has not been confirmed.
But some babies who died had the virus in their brain and it has been detected in placenta and amniotic fluid too.But some babies who died had the virus in their brain and it has been detected in placenta and amniotic fluid too.
Where did Zika come from?Where did Zika come from?
It was first identified in monkeys in Uganda in 1947.It was first identified in monkeys in Uganda in 1947.
The first human case was detected in Nigeria in 1954 and there have been further outbreaks in Africa, South East Asia and the Pacific Islands.The first human case was detected in Nigeria in 1954 and there have been further outbreaks in Africa, South East Asia and the Pacific Islands.
Most were small and Zika has not previously been considered a major threat to human health.Most were small and Zika has not previously been considered a major threat to human health.
But in May 2015 it was reported in Brazil and has spread rapidly.But in May 2015 it was reported in Brazil and has spread rapidly.
It has since also been reported in: Barbados, Bolivia, Colombia, the Dominican Republic, Ecuador, El Salvador, French Guiana, Guatemala, Guadeloupe, Guyana, Haiti, Honduras, Martinique, Mexico, Panama, Paraguay, Puerto Rico, Saint Martin, Suriname and Venezuela.It has since also been reported in: Barbados, Bolivia, Colombia, the Dominican Republic, Ecuador, El Salvador, French Guiana, Guatemala, Guadeloupe, Guyana, Haiti, Honduras, Martinique, Mexico, Panama, Paraguay, Puerto Rico, Saint Martin, Suriname and Venezuela.
"Its current explosive pandemic re-emergence is, therefore, truly remarkable," the US National Institutes of Health said."Its current explosive pandemic re-emergence is, therefore, truly remarkable," the US National Institutes of Health said.
How does it spread?How does it spread?
It is spread by Aedes mosquitoes.It is spread by Aedes mosquitoes.
They are found throughout the Americas except for Canada and Chile where it is too cold for them to survive.They are found throughout the Americas except for Canada and Chile where it is too cold for them to survive.
If they drink the blood of an infected person they can then infect subsequent people they bite.If they drink the blood of an infected person they can then infect subsequent people they bite.
They are the same insects that spread dengue and chikungunya virus.They are the same insects that spread dengue and chikungunya virus.
And, unlike the mosquitoes that spread malaria, they are mostly active during the day, so bed nets offer limited protection.And, unlike the mosquitoes that spread malaria, they are mostly active during the day, so bed nets offer limited protection.
The WHO expects Zika to spread throughout the Americas, but other scientists have warned that countries in Asia could face large outbreaks too.The WHO expects Zika to spread throughout the Americas, but other scientists have warned that countries in Asia could face large outbreaks too.
What can people do?What can people do?
As there is no treatment, the only option is to reduce the risk of being bitten.As there is no treatment, the only option is to reduce the risk of being bitten.
Health officials advise people to:Health officials advise people to:
The mosquitoes lay their eggs in standing water, so people are also being told to empty buckets and flower pots.The mosquitoes lay their eggs in standing water, so people are also being told to empty buckets and flower pots.
The US Centers for Disease Control has advised pregnant women not to travel to affected areas.The US Centers for Disease Control has advised pregnant women not to travel to affected areas.
What is being done?What is being done?
The Brazilian Health Minister, Marcelo Castro, has said a new testing kit is being developed to identify infections quickly.The Brazilian Health Minister, Marcelo Castro, has said a new testing kit is being developed to identify infections quickly.
He also said more money was being put into the development of a vaccine.He also said more money was being put into the development of a vaccine.
Some scientists are also trialling the use of genetically modified sterile mosquitoes that appear to reduce mosquito populations by 90%.Some scientists are also trialling the use of genetically modified sterile mosquitoes that appear to reduce mosquito populations by 90%.
Meanwhile, efforts are under way to kill the mosquitoes with insecticide.Meanwhile, efforts are under way to kill the mosquitoes with insecticide.
Are the Olympic Games under threat?Are the Olympic Games under threat?
Rio de Janeiro is the host city for the 2016 Olympic Games from 5 to 21 August.Rio de Janeiro is the host city for the 2016 Olympic Games from 5 to 21 August.
The Brazilian authorities will be targeting the mosquitoes' breeding grounds in the run-up to the Games.The Brazilian authorities will be targeting the mosquitoes' breeding grounds in the run-up to the Games.
However, it says fumigation will be carried out only on a "case-by-case" basis because of potential health concerns for athletes and visitors.However, it says fumigation will be carried out only on a "case-by-case" basis because of potential health concerns for athletes and visitors.
There is also some hope there will be fewer mosquitoes in August as the month is both cooler and drier.There is also some hope there will be fewer mosquitoes in August as the month is both cooler and drier.
Follow James on Twitter.Follow James on Twitter.