Zika Fever

What is Zika Fever?

Zika Fever is caused by a virus that is related to dengue, yellow fever, West Nile and Japanese encephalitis viruses. The virus was first discovered in 1947 in a rhesus monkey in the Zika Forest of Uganda and was subsequently found to cause an illness when it was found for the first time in humans in 1968 in Nigeria.

How do you get Zika Fever?

Zika virus is transmitted by the bite of infected mosquitoes, the same ones that transmit dengue fever and other mosquito borne viruses. In addition, the virus can be sexually transmitted from human to human.

Susceptibility and Resistance

There is no natural immunity to this virus. So, everyone is susceptible.

Incubation Period

The incubation period for Zika Fever is 3-12 days.

What are the Symptoms?

Zika virus causes a relatively mild flu-like illness beginning with a mild headache, then followed by a skin rash, fever, fatigue, conjunctivitis (redness in the eye), and arthralgia (joint pains). Within 2 days, the rash fades, and within 3 days, the fever ends.

There is strong scientific evidence that this virus is the cause of microcephaly (small brain) and other neurological abnormalities in newborn infants.


Guillain–Barré syndrome is relatively rare condition characterized by the rapid-onset of a neurological illness with muscle weakness that may develop over half a day to four weeks and that may affect the breathing muscles.

Preventative Measures

The only prevention is avoidance of mosquito bites, especially in areas where there is an active outbreak of this virus.

The World health Organization states that pregnant women should be advised not to travel to areas with Zika virus outbreaks. Pregnant women whose sexual partners live in or travel to areas with Zika virus outbreaks should ensure safe sexual practices or abstain from sex for the duration of their pregnancy,

Sexual Transmission Risk after possible exposure

Men or women who have traveled to an area with epidemic Zika may become infected without symptoms. Based on new evidence, the recommended length of time for safer sex practices for asymptomatic males returning from areas with active Zika virus transmission was extended from 8 weeks to 6 months. This is the same length of time as is recommended for symptomatic males. This recommendation now also applies to females, whether or not they have had symptoms. If the man’s partner is pregnant, the couple should either use condoms or not have sex during the pregnancy. It is unknown how long after infection women can transmit the virus to their partners.

Guillain-Barré Syndrome

At present, scientific evidence supporting the association between Zika virus and this syndrome is growing. As a precautionary measure, travellers can minimize the risk of exposure to Zika virus. If neurological symptoms appear after visiting areas where Zika virus is present, travellers should consult their physician immediately.


There is no vaccine or preventive drug for Zika virus, and only treatment of symptoms is possible.

Where Does It Commonly Occur?

Following its discovery in Uganda, the virus has spread to other African countries such as Uganda, Tanzania, Egypt, Central African Republic, Sierra Leone and Gabon, as well as in parts of Asia including India, Malaysia, the Philippines, Thailand, Vietnam and Indonesia and several islands of the Pacific.

The first outbreak of this disease outside of Africa and Asia was in April 2007, on the island of Yap in the Federated States of Micronesia.

In April 2015, a new large outbreak was reported in Brazil in the district of Camaçari and the municipality of Salvador, the capital of the state of Bahia.