Dr Cheng Hung Henry
Obstetrician & Gynaecologist
Dr Leong Hoe Nam, an infectious disease specialist, and Dr Henry Cheng, an obstetrics and gynaecology specialist, talks about the Zika virus and its effects on expecting mothers.
In light of the recent Zika situation in Singapore, Dr Leong would also like to emphasise: The focus now is on getting Singapore well and protecting the citizens, not playing the blame game. The difference of Zika is that the disease is mild unlike the former SARS epidemic. The gatekeepers, now the family physicians, must be aware that Zika symptoms are mild and we must investigate them.
See our video interviews with Dr Leong and Dr Cheng on the Zika virus:
7 Questions on Everything about Zika
All about the Zika virus (part 1): What is it and how it affects us
All about the Zika virus (part 2): How can we protect ourselves
How the Zika virus affects Women and what Precautions Women can take (Subtitled)
5 Quick Questions every Pregnant Woman has about Zika
We have heard of the viruses chikungunya and dengue that are transmitted by mosquitoes. Now there is another one – Zika.
The Zika virus transmitted primarily through the bite of an infected Aedes mosquito. For example, if someone has been infected with Zika and is bitten by an Aedes mosquito, if the mosquito bites you a few days later, you may contract the Zika virus.
The Zika virus spreads through mosquito bites and does not primarily spread from person to person, which means that you can shake hands with a person infected with Zika and you will be fine.
In essence, if we are able to control the breeding of Aedes mosquitoes in Singapore, we are able to control the Zika virus spread in Singapore.
Zika symptoms usually appear as mild and common symptoms of any other viral infection. For most people, it is quite harmless.
80% of the people who acquire the Zika virus may not exhibit any symptoms, ie. no fever. Only 20% of patients may develop symptoms.
Zika symptoms include fever, body aches, headaches and sometimes, a rash or red eyes.
The danger comes when a pregnant woman is infected with Zika. The virus may circulate in the blood stream, go through the placenta and pass on to the baby. Studies have suggested a close relationship between the viral infection and microcephaly, a birth defect in which the child is born with a smaller brain. As the brain is affected, the child will grow up with other issues and abnormalities as well. Hence, at the time of delivery, the doctor will try to find the virus in the placenta through special techniques to confirm the diagnosis of Zika.
The data regarding the relationship between the Zika virus and microcephaly is not yet clear. The presumption is that the earlier into the pregnancy that the mother is infected, the worse the outcome, and the more likely that the Zika virus may transmit to the unborn child.
There is a suggestion that even the mother may be asymptomatic, that is, she may experience no fever, headache or rashes. But yet the child can be born abnormal. Remember that 80% of patients infected with Zika are asymptomatic.
The question is, has there been new mutations or changes in the virus? We need to understand whether there is something unusual or different in the Zika clusters, such as another concomitant reason (environmental or combination new virus/ toxin) that made it different.
We need more studies on this, and urgently.
In its severe form, the baby can die in utero, or born stillbirth. If not, the baby can be born with severe mental retardation. This is a severe and terrible outcome for the parents.
It is not yet clear, but I suspect there will be a spectrum of cases with children with learning disabilities, all the way to severe mental retardation and cerebral palsy.
If you have travelled to areas overseas or locally that are reported to be Zika-infected, you are at a higher risk of contracting the Zika infection.
The real risk applies primarily to pregnant women or women who are trying to get pregnant. Pregnant women should take extra precautions to protect themselves.
The best way is to protect yourself from mosquito bites by applying mosquito repellent or mosquito patches, and taking measures to wipe out mosquito breeding.
The best scientific drug so far to protect yourself from mosquito bites is the mosquito repellent DEET. Spray it everywhere on your body and clothing – on your hands, feet, head, ears, clothing and slippers. Try to keep yourself cool, as mosquitoes tend to go to hot places.
Of course, the home is very important because we know that the mosquitoes breed in water containers like flower pots and jars. Apply the same measures you take to prevent dengue – make sure to clear water collecting containers. You might want to have wire screens on windows and doors to prevent mosquitoes from flying in.
Currently, there are no vaccines or treatments for Zika.
There are tests available to confirm a Zika infection. However, WHO's May 2016 guidelines do not recommend routine Zika testing for asymptomatic pregnant women. If you are concerned, you should discuss further with your doctor.