According to RTS, the first Swiss cases of the disease have been diagnosed. “We probably diagnosed the first case in someone returning from Colombia in November. The patient had a fever, joint pain and a skin rash”, confirmed Noémie Boillat, head of the vaccination unit of Lausanne’s Policlinique Médicale Universitaire (PMU) to RTS. The specialist put the total number of cases in Switzerland at four. One was diagnosed at PMU, one by a doctor in the canton of Vaud, and two by the Swiss Tropical and Public Health Institute in Basel.
What are the symptoms?
WHO describes the symptoms as a mild fever, skin rash and conjunctivitis – inflammation of the outermost layer of the eye and the inner surface of the eyelids, and says these symptoms normally last for 2-7 days. WHO adds that Zika virus disease is usually relatively mild and requires no specific treatment. People sick with Zika virus should get plenty of rest, drink enough fluids, and treat pain and fever with common medicines. If symptoms worsen, they should seek medical care and advice. There is currently no treatment or vaccine.

© Shao-chun Wang | Dreamstime.com
Who is at risk?
Those at greatest risk are unborn children. According to WHO, there is an increasing body of evidence showing a link between the virus and microcephaly, a condition which reduces foetal brain development, and can cause babies to be born with abnormally small heads. In a statement WHO said “A causal relationship between Zika virus infection and birth malformations and neurological syndromes has not yet been established, but is strongly suspected.”
The Economist said that researchers are also trying to confirm whether Zika causes neurological and immune-system problems in infected adults.
Until October last year, when Brazilian doctors saw a spike in cases of microcephaly, the disease was not considered to be a major threat.
How do you catch it?
The Zika virus is transmitted by Aedes mosquito bites. Aedes is the same mosquito that carries yellow fever and dengue.

The Aedes mosquito – © Mrfiza | Dreamstime.com
Where did Zika come from?
The virus was first seen in Uganda in rhesus monkeys in 1947. The first human cases were diagnosed in 1952 in Uganda and Tanzania. Since then there have been mostly small scale outbreaks in Africa, South East Asia and the Pacific Islands. In May 2015, the Pan American Health Organization (PAHO) issued an alert regarding the first confirmed Zika virus infections in Brazil. It has since spread rapidly across Brazil and through much of Central and South America. A graphic in the Economist shows how it has spread from Brazil to 21 countries in the Americas.

A rhesus monkey – © Jan Schneckenhaus | Dreamstime.com
From pandemic to epidemic
According to Lancaster University the Zika virus was previously considered a slow pandemic. Dr. Derek Gatherer said “The sudden apparently explosive spread of Zika virus across the Pacific and into the Americas shows how unpredictable viruses can be.”
Weather conditions associated El Nino are expected to increase mosquito populations adding further to the challenge.
WHO deeply concerned
WHO is deeply concerned about the rapid spread of the virus. There is currently no rapid diagnostic test, no specific treatment and no vaccine. In addition, there is a lack of natural immunity in newly affected regions and the potential for further international spread given the abundance of mosquitos around the world.

World Health Organisation Geneva – Photo source – Yann Forget – Wikipedia
The BBC reports that WHO predicts 3 to 4 million people in the Americas could be infected this year. WHO director general Dr Margaret Chan reportedly said Zika had gone “from a mild threat to one of alarming proportions” and has planned an emergency meeting next Monday in Geneva to decide on the appropriate level of international concern and recommended measures.
The United States Centre for Disease Control and Prevention (CDC) has issued a travel alert for people traveling to regions where Zika virus transmission is ongoing. It recommends protection against mosquito bites and has also published a list of regions currently affected by Zika. They include Cape Verde, the Caribbean, Central America, Mexico, Samoa and most of South America.
Experts are calling on all pregnant women returning from one of these regions who are suffering from a fever to see a doctor.
More on this:
RTS article (in French) – Take a 5 minute French test now
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