Fighting the Zika Virus
Over their lifetime Aedes aegypti mosquitoes may not wander more than a few hundred meters from the source where they emerged as larva without human intervention. Still, the range for the insects is widening, and they have a presence on every continent. Mosquitoes are vectors for multiple blood-borne pathogens, including dengue and the Zika virus, and those are also spreading. The World Health Organization has declared Zika, linked to birth defects first detected in Brazil, a global health emergency. “The disease has no early symptoms, no cure and no vaccine,” explains Nayan Chanda, founding editor of YaleGlobal Online. With Brazil hosting the Olympics in August, the Zika virus could spread more rapidly. Chanda urges nations with warm, set climates that favor mosquitoes to prepare and that starts at the community level: “To begin with, serious effort needs to be made to prepare airports and laboratories to receive people suspected of carrying the infection and administering the required blood tests” and the threat “should be seized as an ideal moment to expand Prime Minister Modi’s Clean India campaign to create mosquito-free areas.” – YaleGlobal
Fighting the Zika Virus
Zika’s victims are next generation. It is suspected to cause a devastating birth defect — brain deformity in babies born to infected mothers. In Brazil alone, some 4,000 cases of microcephaly — that causes babies to be born with smaller than normal heads and developmental retardation — have been detected since May 2015. The disease has no early symptoms, no cure and no vaccine.
Zika originally emerged in Africa, but in the last several months has seen explosive growth in South America and is now threatening the wider world calling for a global response. After SARS, avian flu and Ebola, the latest threat is deemed serious enough for the World Health Organisation (WHO) to take the rare step of sounding the alarm by declaring an international health emergency. The fact that the WHO has swung into immediate action by pouring resources into the search for a vaccine demonstrates the gravity of the situation.
Tom Frieden, director of the US Centers for Disease Control, recently said that Zika could spread widely under two conditions: presence of the specific mosquito species that spreads the virus and crowded communities in warm climates. He may well have been talking about India.
Last year, the governments in Delhi and other large cities in the country had difficulty tackling the escalating rate of dengue infections carried by Aedes aegypti mosquitos, whose incidence had doubled.
The Indian government has said it would be setting up controls to monitor passengers coming from the 28 affected countries. However, only one in five infected show any symptoms. Even if passengers with dengue-like symptoms are detected, whether or not they carry the Zika virus cannot be determined without blood tests for which India lacks the necessary kits. Fortunately, the number of visitors from South America are not as large as visitors from the US (the US has a limited number of cases), Asia and Europe. But that could change this summer with the Olympics being held in Brazil — the ground zero of Zika infection. The presence in Rio de Janeiro of 380,000 visitors from around the world risks turbo-charging the spread of the infection.
The conventional wisdom is that developing a vaccine could take years. In the meantime, governments have to step up efforts to prevent the spread of the virus in a mosquito population that has been growing at an exponential rate thanks in part to global warming.
To begin with, serious effort needs to be made to prepare airports and laboratories to receive people suspected of carrying the infection and administering the required blood tests. The recommendation by some South American health authorities to women in the affected regions to postpone pregnancy is simply unworkable in India. The looming threat of a pandemic that could cause a serious health crisis, to say nothing of heartbreak for mothers of deformed babies, should be seized as an ideal moment to expand Prime Minister Modi’s Clean India campaign to create mosquito-free areas. Not only should government agencies be mobilised but civic organisations could be encouraged and guided to help eradicate mosquito-breeding grounds.
The threat of Zika is the latest in a series brought about by globalisation, but as ever the fight back will need to begin at the local level.
Nayan Chanda is the author of Bound Together: How Traders, Preachers, Adventurers and Warriors Shaped Globalization and is consulting editor of YaleGlobal Online, published by the MacMillan Center, Yale University.
Read about “The global distribution of the arbovirus vectors Aedes aegypti and Ae. Albopictus.” Researchers, led by Moritz UG Kraemer, hypothesized that due to harsh conditions coupled with the onset of the slave trade, Ae. aegypti were introduced into the New World from Africa, from where it subsequently spread globally to tropical and sub-tropical regions of the world (Brown et al., 2014).”