50 people have tested positive for Zika virus in Rajasthan’s Jaipur following which the Prime Minister’s Office sought a detailed report from the Union Health Ministry. This has led to other states stepping up surveillance. Zika doesn’t kill people, yet everyone is scared of it. To understand why, we need to delve deep into the subject.

So what is Zika fever virus? Why is it important?

This is a virus that causes fever and other symptoms among people, and also causes paralysis and neuro-related illnesses in extreme cases.

A fact sheet compiled by the World Health Organisation says that Zika virus is a mosquito-borne flavivirus that was first identified in Uganda in 1947 in monkeys. It was later identified in humans in 1952 in Uganda and the United Republic of Tanzania.

Who carries the virus around? How does it spread?

Zika is caused by a virus transmitted primarily by Aedes mosquitoes, which bite during the day. This is the same mosquito that transmits dengue, chikungunya and yellow fever.

• The virus can be transmitted from a pregnant woman to her foetus.
• Human transmission can also occur through unprotected vaginal, anal or oral sex.
• In some patients, researchers have found that the virus can be shed through saliva and urine.
• It can spread through blood transfusion as well.

The incubation period (the time between exposure to the virus and manifestation of symptoms) of Zika is estimated to be 3–14 days.

Was Zika always present in India?

A study suggests that Zika in India was not associated with any travel history, but has been present for a long time.The environment in India is conducive for ZIKV because of preponderance of the Aedes aegypti and Aedes albopictus mosquitoes which are typically active from dawn to dusk.

Though these mosquitoes breed throughout the year in and around the houses in potable water sources, the density is extremely high during monsoon when a larger number of breeding sites becomes available. High humidity and optimal temperature support their survival for many days; thus, they get opportunity to lay eggs every 3-4 days and have multiple blood meals.

What are the symptoms?

Diagnosing Zika is a very tricky business. This is because in a majority of cases, the Zika Virus infection is asymptomatic – persons do not exhibit symptoms. Those with symptoms usually get ill 3-12 days after being bitten by an infected mosquito.

The symptoms are mild, and overlap with those in other kind of viral fevers like Chikungunya and Dengue. They include fever, rash, conjunctivitis, muscle and joint pain, malaise or headache. Symptoms typically last for 2–7 days. But it is likely that most people with Zika virus infection do not develop any symptoms at all. It is precisely for this reason that Zika is the most-feared fever these days.

What happens to an infected person?

Information about the Zika virus is continuously evolving. But there is scientific evidence to show that  the infection with the virus during pregnancy can cause infants to be born with microcephaly (decreased head size which may lead to developmental delays) and other congenital malformations, known as congenital Zika syndrome. Infection with Zika virus is also associated with other complications in pregnancy, including preterm birth and miscarriage.

An increased risk of neurologic complications is associated with Zika virus infection in adults and children, including Guillain-Barré syndrome (progressive muscle weakness that can lead to temporary paralysis), neuropathy and myelitis (inflammation of the spinal cord).

But with Zika it is not easy to decide what to do when. People usually don’t get sick enough to go to the hospital, and they very rarely die of Zika.

The good thing is that once a person has been infected with Zika, they are likely to be protected from future infections.

How is Zika diagnosed, and how?

A diagnosis of Zika virus infection can only be confirmed by laboratory tests of blood or other body fluids, such as urine or semen. It is difficult to confirm the infection (out of acute phase of 4-5 days) by serology, due to a very high cross-reactivity with DENV (dengue virus).

How to prevent Zika infection?

There is no vaccine available for Zika. Since this is a disease spread by mosquitoes, avoiding mosquitoes is the best prevention one can think of. For this,

• Do not leave any room for stagnated water, sewage, garbage etc.
• Get rid of water containers around dwellings and ensure that door and window screens work properly.
• Tightly cover water storage containers which you can’t get rid of (buckets, rain barrels, etc.).
• For containers without lids, use wire mesh with holes smaller than an adult mosquito.
• Use larvicides to treat large containers of water that may be stored for non-drinking purposes.
• Use an outdoor flying insect spray in dark humid areas where mosquitoes rest, like under patio furniture, or in the carport or garage. When using insecticides, always follow label instructions.
• If you have a septic tank, repair cracks or gaps. Cover open vent or plumbing pipes using wire mesh with holes smaller than an adult mosquito
• Use essential oils of camphor, eucalyptus, citronella, lemongrass etc in oil diffusers, to keep common rooms in homes free of mosquitoes.
• Use mosquito net, sprays and whatever other preventive measure to stay safe from mosquitoes.
• Do not leave clothes open at home, keep them covered in shelves.
• Avoid pile up of clothes in open, especially black clothes, in rooms. Mosquitoes love to take shelter on these.
• Wear neutral-coloured (beige, light grey) clothings. Wear long-sleeved, breathable garments that cover the body parts, while travelling to mosquito-infested areas.
• Apply mosquito repellent creams or oil on open parts of the body while travelling and staying in mosquito-infested areas, or at home when mosquitoes are unavoidable.
• Prevent sexual transmission of Zika by using condoms, or avoiding sex during infection.

How can Zika fever be cured?

According to Centers for Disease Control and Prevention (CDC), there is no specific medicine or vaccine for Zika virus. So,

• Treat the symptoms.
• Get plenty of rest.
• Drink fluids to prevent dehydration.
• Take medicine to reduce fever and pain.
• If you are taking medicine for another medical condition, talk to your healthcare provider before taking additional medication

What care needs to be taken if you are caring for a person with Zika?

One needs to take steps to protect oneself from exposure to the person’s blood and body fluids (urine, stool, vomit). So,

• Do not touch blood or body fluids or surfaces with these fluids on them with exposed skin.
• Wash hands with soap and water immediately after providing care.
• Immediately remove and wash clothes if they get blood or body fluids on them. Use laundry detergent and water temperature specified on the garment labels.
• Clean the sick person’s environment daily using household cleaners according to label instructions.
• Immediately clean surfaces that have blood or other body fluids on them using household cleaners and disinfectants.

If you are pregnant, avoid caring for a Zika patient totally. If it becomes absolutely necessary, take the above steps to avoid infection.