Zika prevention

Researchers are gradually discovering more about the Zika virus and how it spreads in humans. As more is learnt about how the disease passes on to people, the ways of preventing it are growing.

Prevention is important as the disease is being increasingly linked to a rise in microcephaly, a condition that causes defects to the brain and head of new born babies in the womb and to the risk of Guillain-Barré syndrome, a disease that affects the nervous system.

Medicines and vaccinations

There are currently no vaccinations or medicines designed especially for the Zika virus. Scientists at several organisations are working on vaccinations which they hope to bring to clinical trial and then to market to counter the global outbreaks from the disease.

The symptoms from the disease tend to be mild unless they linger in the system and develop into the further complication of Guillain-Barré syndrome. The symptoms of Zika only tend to develop in about 20% of the people who are infected with the virus and they can be treated with rest and over the counter painkillers such as paracetamols. Aspirins and non-steroidal anti-inflammatory drugs should be avoided.

Hygiene

One of the symptoms can be viral conjunctivitis which tends to make the eyes watery. A patient with this should take care to avoid passing on secretions from their eyes via their hands or through sharing a pillow. They should also avoid wearing contact lenses throughout the period of the infection.

Removing stagnant water

The Aedes mosquitoes that spread the disease between humans tend to lay their eggs in stagnant water. People should avoid leaving bowls, vessels and vases of water around their homes to minimise the risk of the mosquitoes using these. An infected mosquito may be able to pass on the virus through their eggs.

Mosquito nets and coverings

Where possible, people should use mosquito nets to protect themselves from mosquitoes throughout the day when they are their most active. This especially applies to pregnant women.

Mosquito screens should also be used over windows to prevent mosquitoes getting into buildings. Also mosquito coils and vapourisers can also reduce the amount of mosquitoes.

Mosquito repellent and insecticides

People in a risk area for the Zika virus should use a mosquito repellent containing N, N-Diethyl-3-Methylbenzamide (DEET) and wear light-coloured clothing covering their arms and legs to deter and prevent mosquitoes from biting them. DEET however, should not be used on children below two months of age. The repellent should be reapplied as directed on the product’s advice information.

The insecticide permethrin, a synthetic chemical, can also be sprayed on clothing to kill mosquitoes when they land on the fabric. Permethrin works on the nervous system of the insects to cause eventual death. Care should be taken in using the insecticide as it can also be harmful to cats as they are unable to reduce it as well as humans and dogs.

Abstaining from sex and using condoms

People in a region with a Zika outbreak should practise safe sex to avoid the risk of passing on the virus. When infected, the virus can pass on to the blood or semen. The risk of sharing either during sexual activity can increase.

The symptoms of the disease only show in about one in five people who have the infection. Men and women should either abstain from sexual activity or use a condom for vaginal, anal or oral sex. The condom should not be reused.

Sharing needles

People should also avoid sharing needles due to the risk of sharing infected blood and passing on the virus.

Travel

Some countries are advising pregnant women to avoid travelling to areas where there is a Zika virus to reduce their risk of catching the disease. Pregnant women should seek advice before travelling.

References

• World Health Organization on Zika prevention: http://www.wpro.who.int/mediacentre/factsheets/fs_05182015_zika/en/
• Centers for Disease Control and Prevention on Zika prevention: http://www.cdc.gov/zika/disease-qa.html
• National Pesticide Information Center on permethrin: http://npic.orst.edu/factsheets/PermGen.html
• NHS Choices on Zika prevention: http://www.nhs.uk/Conditions/zika-virus/Pages/Introduction.aspx#prevention