Zika Virus testing and symptoms of zika virus

Diagnostic Tests for Zika Virus and Symptoms,Treatment for Zika Virus

Most of us would hardly have heard of the Zika virus disease or Zika, as it is commonly known. The Zika is a disease caused by the Zika virus that is spread to the people, primarily through the bite of an infected Aedes species mosquito. The most common symptoms of the Zika virus disease are fever, rash, joint pain, and conjunctivitis. The illness is usually mild, and the symptoms last for several days to a week.

What are the Symptoms of Zika?

The illness caused as a result of the Zika virus is quite mild, and many people do not even realize that they have been infected with the virus.

The most common symptoms of the Zika virus disease are fever, rash, joint pain, or conjunctivitis. The symptoms, usually, begin 2 to 7 days after being bitten by an infected mosquito.

How is the Zika Virus Transmitted?

The Zika virus is transmitted through the bite of infected Aedes mosquitoes. Most of you would remember that it is the same mosquito that spreads Chikungunya and dengue. These mosquitoes are predominantly aggressive daytime biters, but they can also bite at night. Mosquitoes become infected when they bite a person already infected with the virus. Infected mosquitoes then spread the virus to other healthy people through bites. Infected mosquitoes can also transmit the virus from a pregnant mother to her baby during pregnancy.

How is Zika Diagnosed? – Zika Virus Testing

There are no commercially available diagnostic tests for the Zika virus disease. Healthcare providers are encouraged to report suspected Zika cases to their state or local health department to facilitate diagnosis and mitigate the risk of local transmission.

See your doctor or your personal physician if you develop symptoms such as fever, rash, joint pain, and red eyes. If you have recently traveled to any country that has prevalence of Zika, discuss with your doctor for further management.

During the first week after onset of symptoms, the Zika virus disease can be diagnosed by performing Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) on serum. Virus-specific IgM and neutralizing antibodies typically develop toward the end of the first week of illness. Cross-reaction with related flaviviruses (such as dengue and yellow fever viruses) is common and may be difficult to differentiate.

Plaque-reduction neutralization testing can be done to measure virus-specific neutralizing antibodies and discriminate between cross-reacting antibodies in primary Flavivirus infections. Test results are normally available between 4 to 14 days after the receipt of the specimen. The test results can take longer during summer months when the Arbovirus activity increases.

Biological confirmation of ZIKV infections is based mostly on the detection of virus RNA in serum by using reverse transcription PCR (RT-PCR). Although IgM against ZIKV can be detected by ELISA, only a few laboratories have this ability. Thus, in addition to the nonspecific clinical features of infection with ZIKV, laboratory diagnosis is challenging because of low viremia and cross-reactivity of ZIKV antibodies with other Flaviviruses. The diagnosis requires confirmation by neutralization assays and makes rapid serologic confirmation difficult. The diagnostic utility of urine as a source for detection of ZIKV RNA by real-time RT-PCR is also investigated.

Infants should be tested for the Zika virus either if their mothers had a positive or inconclusive test for the virus, or if they were born with microcephaly or intracranial calcifications, and their mothers had resided in or traveled to an area with Zika virus transmission.

The first thing to do for any potentially infected infant is to test the mother, and then the infant for the Zika virus. It should be remembered that even if the infant tests negative, an ophthalmologic evaluation within the first month of life, and a repeat hearing test at 6 months should be done. This should be done as abnormal eye findings and delayed hearing loss has been present in infants potentially infected with the virus.

If the test is positive or inconclusive, but the infant does not present with microcephaly or intracranial calcifications, a comprehensive physical examination, including evaluation for neurologic abnormalities should be done. This should also include full body photographs to check for dysmorphic abnormalities. The infant should also have a cranial ultrasound, unless a prenatal ultrasound showed no brain abnormalities in the third trimester.

Microcephaly is a condition where the circumference of the head is smaller than normal. Microcephaly may be caused by genetic abnormalities or by drugs, alcohol, certain viruses, and toxins that are exposed to the fetus during pregnancy and damage the developing brain. Microcephaly could also be caused by the Zika virus.

Zika virus RT-PCR and serology assays can be performed on maternal serum or plasma. Zika virus RT-PCR can also be performed on amniotic fluid.

Other testing that can performed includes the following:

  • Histopathologic examination and immunohistochemical staining of the placenta and umbilical cord
  • Zika virus testing of frozen placental tissue and cord tissue
  • IgM and neutralizing antibody testing of cord blood.

How do You Prevent Yourself From Being Infected by Zika?

So far, there is no known vaccine to prevent Zika. The best way to prevent the disease is to avoid being bitten.

Protect yourself and your family from mosquito bites by:

  • Wearing long-sleeved shirts and long pants
  • Staying in places with air conditioning or a place that uses window and door screens to keep mosquitoes outside
  • Use approved insect repellents
  • Do not spray repellent on the skin under clothing
  • If you are also using sunscreen, apply sunscreen before applying the insect repellent.

In the Cases of Small Children:

  • Do not use insect repellent on babies younger than 2 months of age
  • Dress your child in clothing that covers arms and legs
  • Cover the crib, stroller, and baby carrier with mosquito netting
  • Do not apply insect repellent onto the child’s hands, eyes, and mouth
  • Do not apply the repellent on cuts, wounds, or irritated skin
  • Spray insect repellent onto your hands and then apply to a child’s face
  • Treat clothing and gear with Permethrin
  • Treated clothing remains protective even after multiple washings

Ensure that you sleep under a mosquito net at all times if you are outside and are not able to protect yourself from mosquito bites.

What is the Treatment for Zika?

There is no vaccine or specific medicine to treat Zika virus infections.

Treat the Symptoms and Follow these Instructions:

  • Get plenty of rest
  • Drink plenty of fluids to prevent dehydration
  • Take medicine to reduce fever and pain
  • Remember not to take aspirin or other non-steroid anti-inflammatory drugs
  • If you are taking medicine for other medical conditions, talk to your doctor before taking any new medication
Medically Reviewed By
Dr. Kaushal M. Bhavsar (MBBS, MD)Assistant Professor in Pulmonary Medicine, GMERS Medical College, Ahmedabad