There is ongoing concern about the spread of the mosquito-borne Zika virus and the impact of Zika infections on pregnant women and their babies. There are also concerns that Zika infection can, in rare instances, lead to Guillain-Barré syndrome, a serious immune system disorder.
Zika is spreading to many tropical and sub-tropical countries. Cases of Zika virus have been reported in Africa, southern Asia, the Pacific Islands, and the Americas.
According to the information available, including the cases reported in New Zealand, the Pacific state where Zika virus infections are currently detected is American Samoa. This list will be updated as the situation changes. The Ministry of Health recommends that if you're travelling to any Pacific Island country, you should always take precautions to avoid mosquito bites.
If you are travelling outside of the Pacific, the most up-to-date list of countries currently infected with Zika virus can be found here: Check the full list of countries with current, confirmed Zika infections on the ECDC's website.
The World Health Organisation stress the continuing need for improved surveillance and education regarding Zika virus as well as promotion of mosquito control efforts. No Zika-related trade or travel restrictions are recommended at this time.
What are the symptoms and who is at risk?
Most people who get infected with the Zika virus do not show any symptoms. Only one in five people who get it will feel sick. The symptoms appear 3-12 days after getting the infection and last from 4-7 days. However, as Zika infection may cause a rash that could be confused with serious diseases such as measles or dengue, these diseases do need to be ruled out.
Symptoms can include:
- low-grade fever (between 37.8°C and 38.5°C)
- joint pain, notably of small joints of hands and feet, with possible swollen joints
- muscle pain
- red eyes
The incubation period is typically 3–12 days. There is no specific treatment for Zika virus infection and if symptoms develop these will typically clear up within 4-7 days. Get plenty of rest and fluids, and treat the symptoms that you have. Use paracetamol for pain and fever if needed. Until dengue can be ruled out do not take aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen, due to a risk of bleeding.
Zika virus is transmitted by mosquitoes (Aedes sp.) that are active during the day. Anyone who is bitten by an infected mosquito is potentially at risk of infection.
Zika virus and pregnancy
There are concerns that pregnant women who become infected with Zika virus can transmit the disease to their unborn babies, with potentially serious consequences. On 14 April 2016 the United States’ Centers for Disease Control and Prevention released a statement concluding that prenatal Zika virus infection is a cause of microcephaly and other serious brain anomalies in developing fetuses. Reports from several countries, most notably Brazil, show that there has been an increase in severe birth defects and poor pregnancy outcomes in babies whose mothers were living in areas while pregnant where Zika virus infections were occurring.
Additional international research is necessary and ongoing to determine the link between Zika virus and foetal damage.
Anyone who is pregnant or plans to become pregnant should defer travel to an affected area. We recommend that women travelling in Zika-affected areas protect themselves against mosquito bites and, if needed, use an appropriate contraception to prevent pregnancy. Women returning from Zika-affected areas should avoid getting pregnant for eight weeks after leaving the affected country.  If their partner has also travelled to a Zika affected area please refer to the information on sexual transmission below.
- Wear long-sleeved shirts and long pants
- Use insect repellents containing DEET, picaridin, oil of lemon eucalyptus (OLE), or IR3535. Always use as directed.
- Insect repellents containing DEET, picaridin, and IR3535 are safe for pregnant and breastfeeding women and children older than 2 months when used according to the product label. Oil of lemon eucalyptus products should not be used on children under 3 years of age.
- If you use both sunscreen and insect repellent, apply the sunscreen first and then the repellent.
- Use permethrin-treated clothing and gear (such as boots, pants, socks, and tents).
- Use bed nets as necessary
- Stay and sleep in screened-in or air-conditioned rooms.
If you're pregnant or trying to get pregnant, and you've recently travelled to an area with Zika, we recommend that you speak with your healthcare provider or lead maternity carer, even if you do not feel sick. It is especially important to see a healthcare provider if you develop a fever, rash, joint pain, or red eyes during your trip or within eight weeks after travelling to a country where Zika has been reported.
Sexual transmission of Zika virus
The risk of Zika virus being spread by means other than mosquito bites is still unclear and is likely to be a very rare occurrence.
There is very limited scientific evidence to suggest the virus can be sexually transmitted. The best way to reduce the possibility of sexual transmission of the virus, or the possibility of becoming pregnant while infected with Zika virus, is to avoid sex or use condoms.
All men who have travelled to a Zika-affected area should avoid sex or use condoms, even if you do not have symptoms.
- If your partner is pregnant, you should abstain from sexual activity or use condoms for the duration of the pregnancy.
- If you have a partner who is at risk of becoming pregnant, you should abstain from sexual activity or use condoms for at least six months after leaving a Zika-affected area. This advice may be updated as further information becomes available. There is only limited evidence available at this time about how long you should abstain from sex or use condoms and international advice  varies. Initial research has found Zika virus present in semen at least two months after infection develops. However how infectious the virus remains and how long it can possibly stay in the semen is not known. Until more information on the duration of sexual transmission becomes available, you should use condoms or abstain from sexual activity for at least six months after leaving a Zika-affected area.
It's important that you abstain from sexual activity or use condoms even if you are not showing symptoms. Only one in five people who get the Zika infection will show symptoms, so it's possible to have the infection and not know it.
In New Zealand, we will continue to update our advice as further information becomes available.
Call Healthline 0800 611 116 if you are unsure what to do.
Reducing the risk of exposure
Because Zika virus is transmitted by mosquitoes mostly active during daytime, it is important that all travellers visiting affected areas continue to take protective measures to prevent mosquito bites throughout the day. Such measures include protective clothing, repellents, and bed-nets where necessary.
The risk of the infection being spread by means other than mosquito bites is still unclear and is likely to be a very rare occurrence. There is very limited scientific evidence to suggest the virus can be sexually transmitted. The best way to reduce the possibility of sexual transmission of the virus, or the possibility of becoming pregnant while infected with Zika virus, is to practice safe sex and use condoms.
We recommend that both men and women use appropriate contraception for four weeks after returning from areas which have current active transmissions of Zika virus.
For more information about Zika virus, see the following websites:
Current infected countries are shown here:
- Ministry of Health: Zika virus
- US Centers for Disease Control and Prevention: Zika virus
- European Centre for Disease Control and Prevention: Zika virus
 These sites include:
- The CDC: http://www.cdc.gov/zika/transmission/sexual-transmission.html
- The World Health Organization: http://www.who.int/features/qa/zika/en/
- The Government of the United Kingdom: https://www.gov.uk/guidance/zika-virus
- See the American Samoa travel advisory
- See the Papua New Guinea travel advisory
- See the Argentina travel advisory
- See the Antigua and Barbuda travel advisory
- See the Aruba travel advisory
- See the Bahamas travel advisory
- See the Barbados travel advisory
- See the Belize travel advisory
- See the Bolivia travel advisory
- See the Brazil travel advisory
- See the Cayman Islands travel advisory
- See the Colombia travel advisory
- See the Costa Rica travel advisory
- See the Cuba travel advisory
- See the Puerto Rico travel advisory
- See the Dominica travel advisory
- See the Dominican Republic travel advisory
- See the Ecuador travel advisory
- See the El Salvador travel advisory
- See the French Guiana travel advisory
- See the Grenada travel advisory
- See the Guadeloupe travel advisory
- See the Guyana travel advisory
- See the Haiti travel advisory
- See the Honduras travel advisory
- See the Jamaica travel advisory
- See the Martinique travel advisory
- See the Mexico travel advisory
- See the Nicaragua travel advisory
- See the Panama travel advisory
- See the Paraguay travel advisory
- See the Peru travel advisory
- See the St. Lucia travel advisory
- See the St. Vincent and the Grenadines travel advisory
- See the Suriname travel advisory
- See the Trinidad and Tobago travel advisory
- See the Turks and Caicos travel advisory
- See the Virgin Islands, US travel advisory
- See the Venezuela travel advisory
- See the Thailand travel advisory
- See the Singapore travel advisory
- See the Malaysia travel advisory
- See the Myanmar travel advisory
- See the Philippines travel advisory
Reviewed:17 Mar 2017, 11:24
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