ZIKA Virus

Introduction:

The Zika virus, a mosquito-transmitted disease, was first identified in the Zika Forest of Uganda in 1947 in the rhesus monkey. Eventually, it got transmitted to humans in 1952. This illness is transmitted by two species of mosquito — Aedes Albopictus and Aedes Aegypti. The Zika virus is similar to yellow fever, dengue, West Nile and Japanese Encephalitis viruses.

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Signs & Symptoms:

The time from incubation to exposure is not so clear but it lasts for 2-7 days.

  • The symptoms are a bit similar to dengue, usually causing mild illness which appears after some days of being bitten by an infected mosquito.
  • Mild fever, skin rashes, headache, muscle and joint pain, and pain behind the eyes may occur in an infected person.
  • Conjunctivitis, vomiting and malaise are some other symptoms of Zika virus.

 Modes of Transmission:

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  • Primarily, the Zika virus gets transmitted to humans through the bite of an infected Aedes mosquito, mainly Aedes Aegypti.
  • Unlike the Anopheles mosquito causing malaria which is active during night hours, the Aedes mosquito is extremely active during daytime; it can survive in both outdoor and indoor environment.
  • When a mosquito feeds on the blood of an infected person, it gets infected itself, transmitting the virus to other humans through bites.
  • Transmission through asymptomatic blood donors in whom RNA of Zika virus has been identified.
  • Possible transmission through sexual contact has also been reported.

Diagnosis:

A Zika virus infected person can be diagnosed through the following ways:

  • The presence of the Zika virus can be based on general symptoms such as mild fever, rash, conjunctivitis, pain, vomiting, uneasiness etc., Zika virus can be suspected through the patient’s place of living and history of travelling.
  • However, proper diagnosis is done by laboratory testing of blood, urine, saliva or other body fluids through the following tests:
  • PCR (Polymerase Chain Reaction) or by RT-PCR (Reverse-Transcription Polymerase Chain Reaction) for viral RNA
  • Serology Test


Treatment:

As the disease caused by Zika virus is usually mild, it does not require much medical attention. Those infected require proper rest, should drink plenty of fluids and take common medicines for fever and pain.

If the symptoms worsen, it is advisable to seek proper medical treatment. Currently, there is no vaccine or specific drugs available to fight the Zika virus.

Prevention:

To protect yourself from Zika virus, the following measures should help:

  • Avoiding mosquito bites is the best prevention.
  • Using insect repellent to kill mosquitoes.
  • Wearing light-coloured clothes that cover most parts of your body.
  • Sleeping under mosquito nets.
  • Covering water containers and emptying them from time to time


Microcephaly and Zika Virus:

Microcephaly is a neurodevelopmental disorder due to which babies are born with unusually small heads. The brains of these babies don’t develop properly during pregnancy or may stop growing in the first year of birth. Children infected with microcephaly experience problems like intellectual defects, developmental delays, hearing loss etc. It may also occur if a pregnant woman is malnourished, has diabetes or consumes alcohol.

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It is found that the rate of babies born with microcephaly in the virus-affected places is rising due to the possibility of pregnant women being infected by Zika virus.

Those travelling to infected areas should take all the preventive measures. Women planning to get pregnant or already pregnant and living in the affected areas should follow the measures strictly. Others should refrain from visiting these places so they don’t get infected.

Virus Affected Zone:

As per the update till 15 February, 2016, the Centers of Disease Control and Prevention (CDC) have warned about travel in the following areas with Zika virus transmission.

  • South and Central America: Brazil, Bolivia, Colombia, Mexico, Costa Rica, Paraguay, Panama, Venezuela Ecuador, El Salvador, French Guiana, Guyana, Guatemala, Honduras, Suriname and Nicaragua
  • Caribbean: Dominican Republic, Puerto Rico, Guadeloupe, Haiti, Jamaica, Barbados, Curacao, Saint Martin, Martinique and US Virgin Islands
  • Oceania: Samoa, American Samoa and Tonga
  • Africa: Cape Verde