Zika virus spreads fear of deadly mosquitoes

The Zika virus is spreading ‘explosively’, warns the World Health Organization. And it is just the latest weapon in the mosquito’s terrifying arsenal. Should we have been more prepared?

‘The day we found out was the worst day of my life,’ says Mila Mendonça in Brazil. Although she had caught the Zika virus while she was pregnant, no one was worried about its minor symptoms; her doctor did not even write it down. But months later her baby, Gabriel, would be born with microcephaly, an abnormally small head which affects brain development. He is just one of 4,000 children born with the condition in Brazil since October.

The virus is spreading ‘explosively,’ warned the World Health Organization (WHO) yesterday. Cases have been found in 23 countries in the Americas, and there could be between 3 and 4 million infections by the end of the year.

The link between Zika and South America’s rising birth defects is not certain, but it is extremely likely. El Salvador has advised women to delay pregnancy until 2018. Brazil’s president says her country must ‘wage war’ against the epidemic.

Her target? Mosquitoes. The tiny insects are responsible for carrying the Zika virus between humans. This particular species can also cause dengue and yellow fever — others can spread malaria, which killed 438,000 people last year. In fact, when natural causes like heart disease and cancer are removed from the equation, mosquitoes are one of the most dangerous killers in the world, far outstripping cars, wars and natural disasters.

‘Half of the global population is at risk of a mosquito-borne disease,’ explains Frances Hawkes, a researcher at the University of Greenwich. ‘They have had an untold impact on human misery.’

And the news gets worse: as climate change raises temperatures and mosquitoes spread further around the globe, many scientists fear that the threat they pose will only become more profound.

Reality bites

The effects of the Zika virus on pregnant women is a horrible new development. But we have known about the scale of mosquito-borne diseases for years, some point out. Our priorities are all wrong: while the government and media have agonised over terrorism and nuclear weapons, the danger of outbreaks of disease have been practically ignored. Even the WHO has been found inadequate when it comes to fighting pandemics. We should all have been more prepared for this.

But we cannot solve all the world’s problems at once, counter others. It is inevitable that governments and journalists will respond to the most immediate situations, and that hindsight will tell us we should have seen them coming. But all we can do now is face the crisis in front of us. Scientists are making breakthroughs in their research. Campaigners and governments are raising awareness of mosquito safety. Together the world will tackle this problem — and then whatever happens next.

You Decide

  1. Which is scarier: a nuclear missile, or a single mosquito?
  2. Should governments focus more on current crises, or long-term problems that don’t make the headlines?


  1. Imagine you are director general of the World Health Organization. List the five biggest problems you would hope to solve.
  2. Create a series of diagrams showing how mosquito-borne viruses are spread, and how to protect against them.

Some People Say...

“Poverty is the real problem. If we can solve that, everything else will fall into place.”

What do you think?

Q & A

Am I at risk from the Zika virus?
Probably not — even if the disease spreads, as predicted, for most people the flu-like symptoms are relatively minor. Protecting pregnant women is the most important concern. Of course, if you are travelling to an area where mosquito-borne diseases are common, you should always be sure to use mosquito nets and insecticide to keep yourself safe.
How quickly will it spread?
According to the WHO, fairly quickly. One major concern is the Olympics, which will take place in Rio this summer; around 10,500 athletes from around the world will travel to Brazil, and risk taking the virus back home with them. The city’s authorities have promised rigorous inspections to get rid of any breeding grounds beforehand, and ‘daily sweeps’ during the games.

Word Watch

Another viral infection spread by mosquitoes in warm climates which affects as many as 400 million people per year, according to the Centers for Disease Control and Prevention.
Yellow fever
This infection gets its name from the jaundice which affects some patients. There are around 200,000 cases a year according to the WHO, and around 30,000 will die of the disease. Unlike dengue and Zika, there is a vaccination.
This statistic is also from the WHO. Malaria cases are decreasing over time thanks to better prevention measures. The WHO estimates a 60% reduction since 2000. Most of the cases are found in sub-Saharan Africa.
Climate change
Mosquitoes thrive in warm climates. As global temperatures rise, they may find it easier to live in countries further from the equator — including the UK.
Scientists have been working to fight the deadly bugs for years. One lab in Indonesia breeds mosquitoes that carry a bacterium which blocks the spread of dengue. The British company Oxitec has released genetically-modified mosquitoes whose larvae will die before childhood.


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