Zika Virus

What is Zika virus?

It is a flavivirus , which is mosquito borne like dengue virus. Zika virus is endemic in Africa and some parts of Asia. Zika virus disease outbreaks were reported for the first time from the Pacific in 2007 and 2013 (Yap and French Polynesia, respectively), and in 2015 from the Americas (Brazil and Colombia) and Africa (Cape Verde).

How it is transmitted?

It is transmitted to people through the bite of an infected mosquito from the Aedes genus, mainly Aedes aegypti in tropical regions. This is the same mosquito that transmits dengue, chikungunya and yellow fever. However it is rarely transmitted through blood transfusion, perinatal , and sexual transmission.

What is the incubation period?

It is generally between 2 and 7 days

What are the signs and symptoms?

1 in 5 people infected with Zika virus get ill. Symptoms can be present from several days to weeks. The symptoms of Zika are similar to those of dengue and chikungunya, diseases spread through the same mosquitoes that transmit Zika.

Common symptoms are;

• low grade fever,
• maculopapular rash,
• muscle pain, joint pain,
• swelling of small joints ,
• headache,
• pain behind eyes, conjunctivitis,
• some neurological symptoms like Gillian Barre syndrome
• death is rare(No reported death)

Recent Zika outbreaks in Brazil are linked to microcephaly in babies born to mothers infected with Zika virus in first trimester of pregnancy. Ultrasound findings done at 18-20 weeks of gestation can show intracranial calcification and abnormal eye findings.

How to diagnose it?

If a person had travelled to the Zika affected area and having symptoms then they should be tested. Reverse transcriptase polymerase chain reaction (RT-PCR) is used for diagnosis. Saliva and urine samples are effective for diagnosis in first 3-5 days after symptom onset and serum in first 1-3 days. Diagnosis by serology(IgM) can be difficult as the virus can cross-react with other flaviviruses such as dengue.

In pregnant females whom to test for the zika virus?

History of travel to affected area and have 2 or more symptoms with in 2weeks of travel History of travel to zika affected are with US finding of fetal microcephaly , intracranial calcification

What is the mode of diagnosis in pregnant female?

• RT-PCR on maternal serum and plasma
• Histopathological , immunohistochemical on placenta and umbilical cord
• Amniocentesis should be considered
• What is the treatment?
• Symptomatic management of the fever.
• Plenty of fluids
• Rest

Do not take aspirin and other non-steroidal anti-inflammatory drugs. Aspirin and NSAIDs should be avoided until dengue can be ruled out to decrease the risk of hemorrhage.

What can people do to prevent becoming infected with Zika?

There is no vaccine to prevent Zika. The best way to prevent diseases spread by mosquitoes is to avoid being bitten. Protect yourself and your family from mosquito bites, use antimosquioto repellants, mosquito nets.

This blog is by Dr. Anoop Misra.