Zika virus is a type of virus belonging to Flaviviridae family and transmitted by Aedes mosquitoes. This virus was first detected in the Zika forest of Uganda in 1947 and hence the name. The symptoms of Zika virus is similar to that of Dengue Fever causing fever, rashes and body pain. But in most of the cases symptoms are mild and go undetected. The infected blood would remain in the body of the person for a week or more during which he/she can transmit the virus to others through exchange of fluids. Zika virus is not very serious like Dengue or Chikungunya fever and it can be controlled and treated fully.
Prevalence :
Zika virus is known to spread symptoms in the equatorial regions of Africa and Asia in the early days. In the year 2014 some cases were reported in the eastern Pacific regions like French Polynesia and Easter Island. In 2015 Zika outbreak was found in Central America, Mexico and the Caribbean regions. Initially Zika virus infection have been reported in many areas of Southeast Asia and Africa. It was in May 2015 the first case of infection was reported in Brazil by PAHO.
CDC (Center for Disease Control and Prevention) of the USA has issued certain guidelines early in January 2016 to restrict frequent travels in affected countries and to follow certain precautions. CDC has also issued specific guidelines for pregnant women since they are at increased risk of getting infected causing problems in newborn babies via mother-to child transmission.
Which States Have Issued Warnings?
Following the impact of CDC guidelines many governments including Dominican Republic, Colombia, El Salvador, Ecuador and Jamaica has issued travel warnings to prevent the risk of getting infected. First case of Zika virus was reported in February 2016 in the Dallas County of Texas which was considered through sexual transmission by infected person.
Symptoms :
Not all the people infected with Zika virus would have symptoms. For many of them there would be no signs or have mild symptoms. Only one person out of 5 people getting this virus would develop symptoms. Broadly speaking the signs of Zika infection is very much like that of dengue fever and chikungunya symptoms. Some of the common symptoms of Zika virus infection are fever, joint pain, rash and reddening of eyes. It can cause Headache and general weakness.
It might take few days for the first symptom to appear after getting transmitted with the virus. Some people have been tested positive for Guillain Barre Syndrome after getting Zika virus infection. Again this virus infection is not that serious and few of them would visit the clinic for the above symptoms. However, the virus can survive in the blood of the person for few weeks before getting transmitted to other person.
Mode Of Transmission or Causes :
It is the Aedes mosquito that carries the Zika virus and transmit it to the person while biting him/her. And more particular it is found that the virus is transmitted by aggressive mosquitoes that bite you during daytime. Human beings are the prime targets of Zika virus though cases of animals have been reported to get infected with this virus.
The worst part of this virus infection it is capable of infecting the in-utero infant when the mother gets infected causing complications before birth. Zika virus cases have also been identified through sexual transmission with an infected person. There is chance for getting infected during blood transfusion of an infected person.
Diagnosis :
Based on the clinical signs of the patient and considering the factors like his/her recent visit to Zika prone areas, the doctor may request for blood test. Blood serum is tested in the laboratory to detect the presence of virus. Zika virus can be detected by conducting RT-PCR serum test and virus specific immunoglobulins. If your body contains neutralizing antibodies, then you are likely to have Zika virus.
Treatment :
- There is no vaccine available for Zika virus and only the symptoms can be treated.
- The person is advised to take plenty of rest and take off from any kind of physical activities.
- The patient should take plenty of fluids and water to prevent dehydration.
- Painkillers like Ibuprofen and acetaminophen can be taken.
- Avoid taking NSAID kind of drugs and don’t give aspirin to children.
- Take all measures to prevent getting bitten by mosquito further.
Can Zika Be Transmitted Through Sex?
Yes. Zika infection can be transmitted through sexual intercourse with an infected person. No data is available to support this theory so far but there is every chance for the virus to get transmitted by exchange of bodily fluids.
Who Are At Risk?
People who are living in Zika virus prone area and those who travel frequently to these regions are at high risk. Till now it is difficult to marginalize specific areas in which the virus transmission is high.
Is There Any Possibility For Spread Of Zika Virus In The USA?
Few cases have been detected in the US Virgin Islands and Puerto Rico regions. However, number of travelers who visit these areas might increase leading to spread of virus in the local states also. You can check the official website of CDC to get updated information regarding spread of virus.
Zika Virus Prevention Tips :
- Mosquitoes are the major source of transmitting Zika virus and hence take every step to prevent Mosquito Bites.
- You can always use insect repellant indoors and outdoors.
- Wear long pants and fully covered shirts to prevent mosquito bite.
- Always use a mosquito net if you are staying outdoors during night.
- Take extra care during daytime where the mosquitoes are aggressive.
- Use only registered insect repellants.
- If you have a baby cover the crib with foolproof mosquito nets and dress him/her fully covered.
- Pregnant women can use EPA marked insect repellants like DEET or IR3535 for added safety.
- Pregnant women can abstain from having intercourse if they suspect their partner is having infection.
Test result interpretation :
Plaque Reduction Neutralization test PRNT is done to detect neutralizing antibodies that are virus specific. Positive IgM for Zika virus or presence of neutralizing antibodies in the serum confirms Zika infection. And if the antibody titers test results are either 4 or more than 4 it confirms Zika virus infection. But there are some challenges in Zika virus testing since cross reasctivity can occur with related virus like dengue or Yellow Fever virus. One cannot totally rely on Zika Virus IgM test alone to confirm the diagnosis since a positive test for IgM can occur due to cross reactivity and vice versa. Hence various factors like the age, health condition and place of travel etc are considered before interpreting the test results.
Zika Virus and Pregnant Women :
Pregnant women are instructed not to visit any areas prone to Zika virus transmission. It is recommended to take up serology test even if they do not show any clinical symptoms. Testing can be done anywhere between 2-12 weeks of pregnancy. Women who reside in ongoing transmission regions are advised not to get pregnant in the near future. Recently CDC has recommended for screening and testing of serum for pregnant women without any symptoms to prevent any complication for the growing fetus.
Is There Any Chance For The Developing Fetus To Get Infected?
Reports are available about the incidence of congenital microcephaly (a rare neurological problem that causes abnormal brain development) in newborns of infected mothers. Zika virus infections is found in several babies who developed microcephaly. Hence there can be relation between Zika infection and complications like microcephaly in infants though the studies have not given clear idea.
Is It Safe For Pregnant Women To Travel To Zika Virus Outbreak Area?
No.
As per the guidelines issued by Center for Disease Control and Prevention (CDC) of the USA any pregnant women should avoid visiting to an area that has an outbreak of Zika virus. It does not matter whether she is any first, second or third trimester of pregnancy. She can discuss this issue with her doctor and if at all she travels, she should take all steps to prevent mosquito bites. And it is wise for women who are planning to get pregnant also not to travel to such areas.
Pregnant Women and Her Partner :
Male partners of pregnant women should be counselled about the risk of passing on the infection to the growing fetus via sex. Hence pregnant women should avoid having sex with such (suspected) partners or insist on using condoms.
Tests For Pregnant Women :
Zika virus test can be done on blood plasma or maternal serum of the pregnant women. RTPCR can be done on the amniotic fluid for detecting the virus. Frozen tissue from the placenta can be tested for the presence of Zika virus and cord blood can be tested for IgM and neutralizing antibodies. In case the test results are positive for Zika virus the women can be considered for Amniocentesis. It is a safe test to decide on various factors like time of delivery and neonatal condition and care. Even if the pregnant women does not have any symptom related to Zika infection she is offered basic testing like serology test and ultrasound scan to ensure that everything is right. Testing can be done anywhere from 2-12 weeks after return from endemic areas.
Testing For Pregnant Women Living In Specific Areas Of Infection :
Pregnant women who are living in ongoing transmission prone areas should undergo regular screening and ultrasound testing throughout their pregnancy irrespective of the trimester. For those with symptoms testing is done with the onset of first symptom and for pregnant women without any symptoms IgM test is done during mid-second trimester. Healthcare providers can counsel women who are not intending to become pregnant about the various strategies for preventing pregnancy. They can teach them about choosing the right method of contraception to prevent pregnancy.
