Dr. Cai Glushak, International Medical Director at AXA Assistance, answers the most frequently asked questions about Zika.
What is the Zika virus?
Zika is a member of the genus Flavivirus and in the same family as dengue and yellow fever. It has been known since 1947, first discovered in Uganda.
Where is the Zika virus found?
It has been responsible for sporadic outbreaks throughout tropical and subtropical zones globally, but only in the last year has developed a foot hold in Latin America and the Caribbean. This is a result of the primary vector, the Aedes Aegyptii mosquito, spreading in distribution across the globe and adapting to habitation in urban environments.
What are the symptoms of the Zika virus?
Zika infection itself causes a very mild illness lasting about one week and causing fever, muscle and joint aches, conjunctivitis (pink eye) and rash. In fact, only one in five individuals ever develops symptoms.
How serious is Zika illness?
There are generally no serious complications to an affected adult or child.
However, The World Health Organization has now concluded that there is sufficient evidence to support a definitive link between infection with the Zika virus and the occurrence of microcephaly in infants born to pregnant women, as well as to the development of Guillain-Barre Syndrome (GBS), a neurological condition.
Is Zika contagious?
Zika normally cannot be transmitted from human-to-human through routine contact. It typically is only communicated by a mosquito that has acquired the virus from one human and then transmits it to another human during a second bite.
However, while human-to-human transmission is rare, it has been established that the infection can be spread through male-female sexual contact. Recently in the U.S., a case of transmission has been reported through homosexual sexual contact as well.
The other means of rare human-to-human transmission is through blood transfusion. For this reason, it is advised that potential donors who have returned from primary Zika-infested areas refrain from donating for at least 28 days.
The incubation period for Zika is thought to be anything between 3-12 days. It is possible that a contagious individual will show no symptoms of having Zika. There is no need to fear transmission by being in close proximity to an infected individual, such as in the same room or on an airplane; or for co-workers to be concerned about acquiring infection from a fellow employee in the workplace.
Is there a test for Zika?
There is no commercially available test as yet. The tests that are available must be done at special public health laboratories. Hence this has made it difficult to confirm the extent of the disease in most populations and the majority of reported cases are “unconfirmed”.
One technique used to identify disease, called PCR, is effective at finding Zika during the acute infection – within 5-7 days of acquiring the virus. Since most infected patients have no symptoms, and for those whose symptoms have abated, a different test must be performed using a technique called ELISA, which tests for IgM antibodies to the virus. However, it is rather nonspecific, in that it cross-reacts with dengue and other related viruses, making it more difficult to definitively diagnose Zika after the acute infection period.
Are the complications of Zika serious?
Both of the aforementioned complications are serious.
Microcephaly is a severe underdevelopment of the brain that usually results in long-term cognitive and neurological deficits. It is a permanent condition.
Guillain-Barre syndrome constitutes a gradual paralysis of the muscles that causes inability to use the arms or legs and may even paralyze the respiratory muscles requiring artificial ventilation. The majority of victims recover after an illness lasting weeks to months while a few patients have long-term disability. Death is rare if properly treated.
By comparison to dengue and malaria, which are common infections in the same regions, serious complications of Zika are much fewer.
Is there any Zika virus treatment or cure?
At present there is no cure for Zika and no vaccine to prevent it. When symptomatic, the Zika virus treatment consists of anti-fever medication, rest and hydration. The main means of prevention is to avoid getting bitten by the Aedes mosquito.
How can I prevent being bitten by the mosquito?
The best means of prevention is to eliminate standing water sources where the mosquito breeds. Apply DEET to the skin (it is safe in adults and children) and wear long sleeves and long leggings. Applying Permethrin compounds to clothing enhances their effectiveness. Since the mosquito generally is only active during daylight hours, sleeping nets are not typically effective at night. However, during the daytime, screens and air conditioning help protect interior environments.
What should pregnant women do?
The World Health Organization advises that women who are pregnant or are planning to become pregnant avoid travel or expatriation to Zika infected countries. In addition, pregnant women are advised to use condoms or avoid sexual relations with a male partner who has returned from a Zika country for the duration of the pregnancy. If you are pregnant and think you have been exposed, your obstetrician is advised to monitor your pregnancy with ultrasounds and testing for Zika under certain circumstances. Microcephaly will begin to be identifiable on ultrasound after the 18th week of pregnancy.
What should women who have travelled to a country with Zika do, if they return home to discover that they’re pregnant?
The key thing to do is to contact your GP, who will advise whether tests are necessary.
If I have had Zika, will I develop immunity?
Yes, once infected, you develop antibodies to the virus which protect you from infection in the future. You will neither get sick nor will you be able to pass on Zika through sexual relations or by giving blood.
What about donating blood?
The NHS Blood and Transport Service has determined that individuals returning from Zika affected countries defer donating blood for 28 days following their return.
Will it be safe to attend the Olympics in Rio de Janeiro in 2016?
The WHO (World Health Organization) considers there is no reason to change plans to hold the Olympic Games in Brazil in August 2016. Because Zika poses little risk of serious illness to adults and children, the only individuals considered at risk for travel to the Olympics are pregnant females, who are advised not to attend. Brazil authorities are launching aggressive mosquito control measures, particularly in Rio and it is expected there will be some improvement in mosquito prevalence by the time of the games. Basically there is little risk to males and non-pregnant females. Obviously, it’s advisable to check the latest travel advisory to the region – as outlined in our ‘Useful links’ section below.
What about the cases of Zika reported in the U.S. and Europe – is Zika spreading there?
The Centres for Disease Control and Prevention (CDC) and the Florida Department of Health have recently identified an area in Miami where the Zika virus is being spread by mosquitos.
It has not been found to be imported from other areas and is thought to originate from an area where conditions that can spread Zika, such as standing water hospitable to mosquitoes who carry the disease, were found.
Four people were found to be infected who lived near to these areas and the Florida Department of Health has initiated aggressive mosquito control measures to reduce the likelihood of this spreading.
In light of this development, people have been advised to take precautions when travelling to this area.
Further information can also be found here: http://www.cdc.gov/zika/intheus/florida-update.html
Is Zika likely to spread to cooler climates?
This is unknown. However to-date, as with dengue, Zika has yet to become established in Europe or the U.S. or Canada, presumably because the mosquito that transmits it cannot yet survive through winter in these regions. Scientists and epidemiologists are watching carefully to see if these mosquitos adapt to these climates and therefore are more able to carry the disease to other regions where it is not yet established.
Summary of recommendations:
• Pregnant women or those contemplating pregnancy should avoid travel to areas with known local Zika transmission. They should also avoid sexual relations or use strict condom precautions with male partners with recent travel to Zika zones.
• All travellers to and residents of Zika infested areas should use enhanced mosquito protection measures including use of DEET containing mosquito repellents and use of long-sleeved clothing, especially during the daytime.
• Avoid accumulation of standing water where mosquito’s breed.
• Pregnant women with any concern for infection with Zika based on symptoms or contact with a male partner at risk of transmitting Zika should be monitored closely by their doctor throughout their pregnancy.
World Health Organisation
Public Health England
National Travel Health Network and Centre (NaTHNaC), an organisation set up by the Department of Health to protect the health of British travellers
European Centre for Disease Prevention and Control – provides an update on those countries with the Zika Virus:
Royal College of Obstetricians and Gynaecologists – Q&As on Zika and pregnancy