Clinical Manifestation​

The most common symptoms of Zika virus infection are fever and skin rash, usually accompanied by conjunctivitis, muscle or joint pain and general malaise. These symptoms are usually mild and last for a few days. Neurological and autoimmune complications are infrequent. Recently Brazil health authorities have observed an increase in babies born with microcephaly in northeast Brazil. 

Mode of Transmission

Zika virus is mainly transmitted to humans through the bite of an infected Aedes mosquito. Aedes aegypti, which is currently not found in Hong Kong., Other Aedes mosquito species such as Aedes albopictus widely present locally are also considered as potential vectors. 

Zika virus can also be transmitted through blood Or sexual transmission.

Incubation period

Symptoms typically begin 2-7 days after the bite of an infected mosquito.


There is no specific medication for Zika virus infection and the mainstay of treatment is symptomatic relief and prevent dehydration. If symptoms worsen, they should seek medical care and advice.

Prevention of Zika virus infection

At present, there is no effective vaccine against Zika virus infection. To prevent Zika virus infection, members of the public are reminded to protect themselves from mosquito bites and help prevent their proliferation. 

Since Zika virus can also be transmitted through sexual contact, barrier sex is recommended for those, or their partners, who have travelled to the infected areas.

Health Advice to prevent Zika virus infection

The incubation period is not clear, but is likely to be a few days to a week.​

1.      Wear loose, light-coloured, long-sleeved tops and trousers, and use DEET-containing insect repellent on exposed parts of the body and clothing;

2.      Take additional preventive measures during outdoor activities:

  • Avoid using fragrant cosmetics or skin care products;
  • Re-apply insect repellents according to instructions;

3.      Special notes when travelling abroad:

  • If going to affected areas or countries, travellers, especially people with immune disorders or severe chronic illnesses, should arrange a consultation with a doctor at least six weeks before the journey, and follow extra preventive measures to avoid mosquito bites;
  • During the trip, if travelling in endemic rural areas, carry a portable bed net and apply permethrin (an insecticide) on it. Permethrin should not be applied to the skin. Seek medical attention as early as possible if feeling unwell;
  • Travellers who return from affected areas should apply mosquito repellent for 14 days after arrival to Hong Kong. Those feeling unwell e.g. running a fever, should seek medical advice as soon as possible and provide travel details to doctor;

4.      Special notes for pregnant women and women preparing for pregnancy:

  • Pregnant women should consider deferring their trip to areas with past or current evidence of ongoing Zika virus transmission. Those who must travel to any of these areas should seek medical advice from their doctor before the trip, strictly follow steps to avoid mosquito bites during the trip, and consult and reveal their travel history to their doctor if symptoms develop after the trip;
  • Women preparing for pregnancy should also consult their doctor before travelling to these areas, strictly follow anti-mosquito precautions during the trip, and report to their doctor if feeling unwell after the trip ​

5.      Special notes for prevention of sexual transmission:

If a female partner is at risk of getting pregnant, or is already pregnant, condom use is advised for a male traveller:

  • ​for 28 days after his return from an active Zika transmission area if he had no symptoms of unexplained fever and rash; or
  • for six months following recovery if a clinical illness compatible with Zika Virus Infection or laboratory confirmed Zika Virus Infection was reported.​​​
Last Updated: Aug 2017
Please note that all medical health articles featured on our website have been reviewed by Quality Healthcare doctors. The articles are for general information only and are not medical opinions nor should the contents be used to replace the need for personal consultation with a qualified health professional on the reader’s medical condition.