This past spring, we changed our travel plans to the Caribbean due to concerns about Zika virus. At the time, travel advice in the public domain was sketchy. Not sure what to expect, we defaulted on the side of caution and ended up heading to Zanzibar instead.

As research progresses on the threat of Zika virus, we invited our friend Dr. Sasha Ho Farris Nyirabu to address some commonly asked questions and share her insights from current research. More importantly, she shares some great preventative advice to heed when travelling to areas where Zika virus is prevalent.


A shrinking global village

Our global village has become smaller thanks to the accessibility of travel via multiple means including cruise ships, air, rail and road.  People of all ages are able to cross countries off of their bucket lists and experience different cultures, cuisines, languages, races, climates, and geographies.  A new generation of undeterred travellers seek to be ethical nomads, gaining various types of enlightenment and wisdom from their experiences as they journey through some incredible countries.

As the topic of Zika virus has remained in the news headlines, the conscientious traveler could benefit from some practical travel guidance. Note however that Zika virus is still being studied.  Therefore, the information presented below is based on current understanding from reports, research publications and recommendations which are subject to change as more data emerges.


What exactly is Zika?

Zika is a flavivirus that can be passed on to humans by mosquito (Aedes species) bites. These mosquitoes are also responsible for spreading yellow fever, dengue, and chikungunya. You can also be infected by Zika virus if you have sex with someone who is infected (sexual transmission).

Mosquito poised to bite


Origins: Where did Zika come from?

Zika virus was first described in infected rhesus monkey serum from the Zika Forest of Uganda (April 1947) 1. Scientists were studying yellow fever in monkeys at the time. Uganda and the United Republic of Tanzania reported Zika cases in 1952 2. Brazil reported an association between Zika virus infection and Guillain-Barré syndrome (July 2015)3 as well as an association between Zika virus infection and microcephaly 4.



How can I get infected?

A few possibilities for infection are listed below.

  1. Mosquitoes: A mosquito bites an infected person ‘A’ and gets infected. The infected mosquito then travels and bites another person ‘B’, thereby infecting person ‘B’.
  2. Sexual transmission: Having sex, even if the infected person does not display any symptoms. Ongoing studies are trying to determine how long the virus stays in vaginal secretions and semen of infected individuals as well as how long they can infect other people. According to the most recent data, Zika remains longer in semen than in urine, blood, or vaginal fluid.
  3. Blood transfusions: Data recorded in Brazil and French Polynesia demonstrates some people becoming infected after receiving blood products (transfusions)5. There have also been reports of lab workers infected with Zika virus.
  4. Sweat or tears: The New England Journal of Medicine recently reported a case (Utah) where a patient in a local hospital seemed to acquire Zika virus from touching an infected patient’s sweat or tears without gloves. There is ongoing research and investigation into this and there have not been official guidelines or recommendations released yet.

See this useful illustration from the Centers for Disease Control and Prevention (CDC) describing how Zika virus spreads.


How do I know if I am infected with Zika virus?

If you have been exposed to Zika virus, it may be appropriate to get tested. You can give a urine or blood sample to be tested in a laboratory. For specific questions, speak with your healthcare provider regarding current guidelines and recommendations.

Mosquito resting on a leaf


If I am infected, how long before I get sick?

Zika has been found in semen, blood, urine, fluid surrounding the baby in the uterus (amniotic fluid), saliva, and CSF (protective fluid around the brain and spinal cord). From the time of infection, no one is quite sure exactly how many days it takes before becoming ill. NOTE: Incubation time = the time from exposure to symptoms 6.


What symptoms should I look out for?

If you are infected, you might experience fatigue, headache, malaise, eye irritation (conjunctivitis), joint pain, headache, muscle pain, and rash. If you have symptoms, they are usually mild and normally last up to a week. Note that you also could be infected but asymptomatic i.e., not displaying any symptoms at all, feeling completely normal.

Riding a dhow in Zanzibar | via @dipyourtoesin


If I am infected, what else could happen?

If you are pregnant it could have an effect on your baby, leading to microcephaly (a condition where an infant’s head is significantly smaller than the heads of other children of the same age and sex 7). There have been some cases of other possible birth defects such as eye defects, hearing loss, and impaired growth. Other reports describe an association of Zika with Guillain-Barré syndrome 8 (a rare disorder where your body’s immune system attacks your nerves 9).

  • It is important to note that there is ongoing research around microcephaly. There are many causes of microcephaly, including exposure to toxins, infections, and hereditary factors (i.e, what genes your parents passed down to you).


How do I protect myself and others?

Say no to the mosquito!

  • It is so important to prevent mosquito bites by using a repellent such as DEET (diethyltoluamide), or Icaridin/Picaridin (KBR 3023, hydroxyethyl isobutyl piperidine carboxylate) and following the product instructions accordingly 10. Note: You should apply your sunscreen and allow 10-15 minutes drying time before applying the mosquito repellent, not the other way around.
  • It is advisable to wear light-coloured clothing that covers arms and legs to also decrease the surface area available for bites.
  • When possible it is also a great idea to travel with a pop-up (i.e., no screws needed) mosquito bed net which is lightweight and insecticide treated (e.g, with a repellant such as permethrin).
  • Many outdoor supply stores also sell clothing items that are pre-treated with permethrin which will remain for several washes, and provide an extra level of protection. If you have a choice in accommodation, screened windows and doors is a good idea.

Mosquito nets at Zanzi Resort in Zanzibar | via @dipyourtoesin


Sex or no sex?

When it comes to sex, be active in your preparation. No sex (abstinence) is a choice which ensures no risk of sexual transmission. However, if this is not possible, be aware that both male and female condoms reduce the risk. That being said, condom use is only effective when the user follows correct instructions.

Condoms must be placed appropriately before any sexual contact starts and only removed when contact is finished between partners. This is true for all types of sex – oral, anal, and vaginal. For oral sex, oral barriers such as an oral dam/dental dam may be used. If there is any use of sex toys, use a new condom with each use.

According to the CDC, anyone who has travelled to a place with Zika virus is advised to abstain or use barrier methods when having oral, anal or vaginal sex as follows:

  1. At least 8 weeks after a Zika diagnosis or start of symptoms if the traveling partner is female.
  2. At least 6 months after a Zika diagnosis or start of symptoms if the traveling partner is male. This extended period is because Zika stays in semen longer than in other body fluids.
  3. At least 8 weeks after returning if the traveling partner (male or female) has no symptoms 11.

Note: The CDC recommends that if you know you are pregnant, do not travel to an area where there is active Zika virus transmission occurring.


Is there a vaccine? How do I get treated?

There is currently no vaccine for prevention. There is no specific treatment for Zika at present either. Contact your healthcare provider for recommendations based on your specific symptoms.



Which countries are safe to travel to and how do I prepare?

  1. Country by country guidance: The National Travel Health Network and Centre (NaTHNaC) was commissioned by Public Health England to provide excellent up-to-date information and recommendations for travelers, including pregnant women. You can click on each country in this alphabetic listing for specific country information.
  2. Global Zika virus distribution: If you want to track Zika virus distribution, the World Health Organization has a fantastic timeline. Click here to view.
  3. Virus updates and recommendations: Also, the CDC has an excellent website with pages dedicated to providing Zika Virus updates and recommendations.
  4. Track new reported cases: The European Centre for Disease Control has a user-friendly resource to track new reported cases.  For instance, there are new cases reported in Florida, Malaysia, Singapore, and Thailand.


The choice is yours

With all the information and guidance available around Zika virus, ultimately the choice remains in your hands. Conduct your own risk assessment and decide what level of risk you are comfortable with. Safe travels!




Dr. Sasha

Dr. Sasha Ho Farris Nyirabu currently works as a Travel Medicine Consultant; a GP with focused training for remote Indigenous communities and a MSc in Control of Infectious Diseases from London School of Hygiene and Tropical Medicine.   She is passionate about management and program design ranging from infectious disease control to campaign promotion for increased access to health care.  Past work, study and research included travels to Borneo, Uganda, Honduras, China, Rwanda, Thailand, Burkina Faso, Malaysia and the West Indies.  Linkedin Profile



  • 1 Trans R Soc Trop Med Hyg (1952)46 (5): 509-520.doi: 10.1016/0035-9203(52)90042-4
  • 2 Hayes EB. Zika Virus Outside Africa. Emerging Infectious Diseases. 2009;15(9):1347-1350. doi:10.3201/eid1509.090442.
  • 3 Araujo, LM; FERREIRA, MLB and NASCIMENTO, OJM. Guillain-Barré syndrome associated with the Zika virus outbreak in Brazil. Arq. Neuro-Psiquiatr. [online]. 2016, vol.74, n.3 [cited 2016-09-22], pp.253-255. Online version available here.
  • 4 Jaenisch T, Rosenberger KD, Brito C, Brady O, Brasil P, Marques E. Estimating the risk for microcephaly after Zika virus infection in Brazil. [Submitted]. Bull World Health Organ. E-pub: 30 May 2016. DOI: available here
  • 5 Musso, Didier et al. Zika virus: a new challenge for blood transfusion. The Lancet , 1993 – 1994,Volume 387 , Issue 10032
  • 6 Source: WHO
  • 7 Source: Mayo Clinic
  • 8 Paploski IAD, Prates APPB, Cardoso CW, Kikuti M, Silva MMO, Waller LA, et al. Time lags between exanthematous illness attributed to Zika virus, Guillain-Barré syndrome, and microcephaly, Salvador, Brazil. Emerg Infect Dis. 2016 Aug. Available here.
  • 9 Source: Mayo Clinic
  • 10 Petersen EE, Staples JE, Meaney-Delman, D, et al. Interim Guidelines for Pregnant Women During a Zika Virus Outbreak — United States, 2016. MMWR Morb Mortal Wkly Rep 2016;65:30–33. DOI: available here
  • 11 Source: CDC
  • 12 Source: CDC