By Eduardo Gonzales, MD
Is it true that the World Health Organization has declared Zika as no longer a public health emergency? Does this mean the virus has been contained? What is the situation in the Philippines with regard to this virus? —email@example.com
Last Nov. 18, the World Health Organization (WHO) has indeed changed Zika’s classification from “international emergency,” its categorization since February 2016, to “significant enduring public health challenge.” This status change was because of the waning number of new Zika infections worldwide and not because the virus has been contained. With the declaration, WHO is in fact saying that the Zika virus will persist as a health issue for years to come.
What is the Zika virus?
The Zika virus causes Zika fever, a mosquito-borne illness. The virus was first isolated in 1954 in the Zika forest of Uganda. It was endemic within a narrow equatorial belt from Africa to Asia until 2014 when it spread eastward across the Pacific Ocean to French Polynesia, then in 2015 to Central and South America. The virus has since spread to more than 50 countries, including the Philippines.
Zika virus transmission
The Zika virus is transmitted to humans primarily by the Aedes aegypti mosquito, the same mosquito that transmits dengue and Chikungunya viruses. Aedes mosquitoes acquire the virus when they bite a person with Zika fever. They then spread the virus to other people through bites.
The Zika virus can also be transmitted from a pregnant mother to her baby and through sexual intercourse. It can probably also spread through blood transfusion, but this has not been confirmed.
Usual course of Zika fever
Zika fever is generally a mild, self-limiting illness that lasts for several days to a week. Often, the disease does not even cause any symptoms. If symptoms occur, they appear two to seven days after infection and include fever, skin rash, joint pain, and redness of the eyes. Once a person has been infected with Zika, he/she is likely to be immune from future infections.
Why Zika fever is dreadful
Despite being a benign illness, Zika fever is a cause of grave concern because in pregnant women it can give rise to an infant with microcephaly, a condition where the head and brain are smaller than normal and which is linked to numerous nervous system problems such as seizures, developmental delay, intellectual disability, and vision, hearing, gait, and balance impairments. The connection between Zika and microcephaly first came to light in 2015 in Brazil. To date, more than 1,800 cases of microcephaly have been confirmed in that country.
There have also been increased reports of Guillain-Barré syndrome, an uncommon disorder of the nervous system that causes temporary paralysis, in areas affected by Zika.
Zika in the Philippines
Our Department of Health (DOH) has so far recorded 33 Zika cases in our country—12 in Iloilo; four in Bacoor, Cavite; three each in Mandaluyong and Calamba, Laguna; two each in Antipolo, Las Piñas, and Muntinlupa; and a case each in Cebu, Quezon City, Makati, Caloocan, and Manila.
Two of the Zika patients, one each from Cebu and Las Pinas, were pregnant when they contracted the infection, but exams indicate their babies are normal.
Ways to prevent Zika infection
There is no vaccine against the Zika virus yet, although scientists are furiously working on it. Hence, at the moment, the best way to prevent Zika fever is by applying the same anti-mosquito bite measures that are recommended for dengue.
In addition, because the virus can be transmitted sexually, people who have traveled to areas with active Zika virus transmission should practice safe-sex (i.e., use condom) or no sex for six months (for men) or eight weeks (for women). Sex includes vaginal, anal, and oral sex and the sharing of sex toys.
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