Monday, 14 March 2016

WORLD:-ZIKA- Humankind v the Culicidae

As the world focuses on Zika's rapid advance in the Americas, experts warn the virus is just one of a growing number of continent-jumping diseases carried by mosquitoes threatening swathes of humanity. The battle against the insects on the streets of Brazil is the latest in an ancient war between humankind and the Culicidae, or mosquito, family which the pests frequently win.

Today, mosquito invaders are turning up with increasing regularity from Washington DC to Strasbourg, challenging the notion that the diseases they carry will remain confined to the tropics. Ironically, humans have rolled out the red carpet for the invaders by transporting them around the world and providing a trash-strewn urban landscape that suits them to perfection. 
The Aedes aegypti species blamed for transmitting Zika breeds in car tyres, tin cans, dog bowls and cemetery flower vases. And its females are great at spreading disease as they take multiple bites to satisfy their hunger for the protein in human blood they need to develop their eggs.
Around the world, disease-carrying mosquitoes are advancing at speed, taking viruses such as dengue and Zika, plus a host of lesser-known ills such as chikungunya and St. Louis encephalitis, into new territories from Europe to the Pacific. The concern is that we have these species spreading everywhere. Today the focus is on Zika but they can carry many different viruses and pathogens. 
In 2014, there was a large outbreak of chikungunya, which causes fever and joint pains, in the Caribbean, where it had not been seen before, while the same virus sickened Italians in 2007 in a wake-up call for public health officials. Europe has seen the re-emergence of malaria in Greece for the first time in decades and the appearance of West Nile fever in eastern parts of the continent.
Out in the Atlantic, the Madeira archipelago reported more than 2,000 cases of dengue in 2012, in a sign of the northerly advance of what - at least until Zika - has been the world's fastest-spreading tropical disease.
In the past 40 years, six new invasive mosquito species have become established in Europe, with five arriving since 1990, driven in large part by the international trade in used vehicle tyres. Mosquitoes lay their eggs in the tyres and they hatch when rain moistens them at their destination.
North American health experts are also racing to keep up, with the first appearance of Aedes japonicus, an invasive mosquito, in western Canada last November and Aedes aegypti found in Washington DC, apparently after spending the winter in sewers or Metro subway stations.
The speed of change in mosquito-borne diseases since the late 1990s has been unprecedented. For many experts, the biggest potential threat is Aedes albopictus, otherwise known as the Asian tiger mosquito, which is expanding its range widely and is capable of spreading more than 25 viruses, including Zika.
In the United States, Aedes albopictus has been found as far north as Massachusetts and as far west as California. In Europe it has reached Paris and Strasbourg. Adding to the challenge for public health authorities are the blurred lines between diseases carried by different mosquitoes, as shown by research in Brazil this month that another common mosquito, Culex quinquefasciatus, may also be able to carry Zika.
There have been some victories against mosquitoes, thanks to insecticide-treated bed nets and vaccines against viruses like yellow fever and Japanese encephalitis, as well as a new one for dengue approved in December. But mosquitoes still kill around 725,000 people a year, mostly due to malaria, or 50 percent more than are killed by other humans, according to the Bill & Melinda Gates Foundation.
Climate change adds a further twist. A 2 to 3 degree Celsius rise in temperature can increase the number of people at risk of malaria by 3 to 5 percent, or more than 100 million, according to the World Health Organization. Hotter weather also speeds up the mosquito breeding cycle from around two weeks at 25 degrees to 7 to 8 days at 28 degrees, according to the Institut Pasteur's Failloux.
A public health emergency is, above all, a human crisis, But its consequences do not end there. A major emergency, whether its severity is real or perceived, can have a significant economic and political impact. Now the World health Organization has declared the Zika virus an ''International public health emergency'', warning that the mosquito-borne pathogen is spreading explosively, the Zika outbreak has become loaded with even more political power. 
There is some evidence that Zika may be linked to Guillain Barre Syndrome, a fully-body paralysis that, if confirmed, could make Zika seem much more menacing, because it can potentially have a devastating impact in a much larger segment of the population. For political leaders, the challenge is multifaceted, and if handled with defines, it is not without potential benefits. 

Leaders must demonstrate a combination of empathy and competence. The more serious the crisis grows, the higher the stakes. For politicians who are in government, the cost of failure could prove politically fatal. Ineptness in confronting Zika will magnify the impact of their perceived weakness. But even those out of government, especially those who are currently candidates for high office, will need to manage the problem with great care. For now, it is largely Latin American and Caribbean leaders who are facing the demands of dealing with Zika. 

The epicenter of the outbreak is in Brazil, where the disease may have arrived from Africa, brought by fans attending the 2014 World Cup. The timing of the crisis in Brazil gives it a potentially enormous political impact. Zika comes at the intersection of several important developments. 

First, President Dilma Rousseff is fighting for her political life. She is trying to avoid impeachment, and her approval ratings have sunk into single digits, which could make her handling of Zika make-or-break for her.  Second, the country is entering its annual Carnival period, a nation-wide, week-long street party, which could make it easy for the virus to spread more rapidly. Third, Brazil is preparing to host the Olympic Games this summer. This means that if the spread is not contained, the cost in tourism revenue could bring another blow to the already struggling Brazilian economy. In fact, you can count Brazil's current economic brittleness as the fourth item on the list. And yet, Zika does not bring only political downside. 

Like all crises, the virus has the potential to repair political careers. And if there is one political career that could use some repairing these days, it is Rousseff's. It is no secret that having an external enemy can work wonders for an embattled leader. The enemy is not usually a mosquito, but Zika and its vector might just do. Presidents and Kings have long known they can from facing outside enemies, in the form of the familiar rally-round -the flag effect seem during times of war. A well-managed war against Zika might just produce a sense of national unity and common purpose that could boost the standing of Brazil's leader. 

So is it time to wipe out mosquitoes altogether? Aggressive action in the 1950s and 1960s, including the use of the pesticide DDT, certainly pushed them back for a while. Today, genetic modification, radiation and targeted bacteria are being considered. Trying to eliminate all mosquitoes, however, would make no sense, since there are 3,549 species and fewer than 200 bite humans.

The strategy is to eliminate mosquito breeding grounds, distribute insecticide and give help to families of afflicted children. The outbreak also has the potential to bring change on another level, challenging the calculus on politically charged social issues, as is already happening on the issue of abortion. 

Par Guylain Gustave Moke
Investigative Journalist
Political Analyst/Writer
World Affairs Expert


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