As the Zika virus continues its migration into the US via Puerto Rico and Florida, disease experts in Southeast Asia have warned it may be almost impossible to contain. The ominous news comes from specialists in Singapore, where Zika is spreading rapidly alongside dengue fever (another contagious disease carried by mosquitoes that can cause severe joint and muscle problems).
“We will not be able to eradicate Zika,” says Dr. Asok Kurup, an infectious diseases specialist at Mount Elizabeth Hospital in Singapore. “We have a huge challenge in that. We have no vaccine; we have no drugs; we have no targeted measures apart from what we have already done for dengue.”
Some common symptoms of Zika virus include rash, fever, red eyes and joint pain. But far more concerning is its potential to cause birth defects—particularly a condition called microcephaly that results in children being born with abnormally small heads and underdeveloped brains—if contracted by pregnant women. Several cases have already been reported in South America, and with Zika now hitting the US, the CDC has bluntly warned that America is “about to see a bunch of kids born with microcephaly.”
The lack of a vaccine is a huge impediment to containing the virus. Several candidates are currently being rushed through clinical trials, but it’s thought we won’t have an effective treatment until at least spring 2017. The longer we have to wait, the further Zika will spread and the greater its impact will be on public health, so we can almost certainly expect the epidemic to get worse before it starts to get better.
Vector control measures are about the only recourse we have at the moment; Florida, for example, has begun aerial insecticide spraying to try and contain the mosquito population around Miami Beach. But with such a large affected area and a highly mobile population (as is the case right across the US), it’s difficult to see targeted campaigns like this having much of an impact.
Another major problem with eradicating Zika virus is that most cases are generally asymptomatic, or only mildly symptomatic, so the patient may not even realize they’re carrying the disease. “Eighty per cent of the people who are infected don’t have any symptoms,” says Dr. Wong Sin Yew, a specialist from Gleneagles Hospital in Singapore. “So it’s possible for somebody who did not seek medical attention to be a source for mosquitoes to bite and infect others and these so-called ‘silent carriers’ could form a source of infection elsewhere and then develop other clusters.”
Despite these challenges, one would like to think that a cure for Zika is just a question of “when,” not “if.” But according to some, that may not necessarily be the case. “It will become inevitable that Zika may just take up permanent residence,” says Dr. Leong Hoe Nam, another specialist from Mount Elizabeth, regarding the outlook for the virus in Singapore. Let’s hope, for their sake and ours, that he’s wrong.
Q: Are you concerned about the spread of Zika virus into the United States? Share your thoughts in the comments below.