Invasion of the Asian tiger mosquito

Charles Ebikeme — Fri, 15 Feb 2013 07:45:06 +0000

Sometime during that glorious decade known as the 1980s, a shipment landed in Houston, Texas. A shipment carrying more than its cargo. The point of origin was Japan. The shipment was used tires. The payload was Asian tiger mosquitoes.

Within years of landing in Texas the tiger mosquito, Aedes albopictus, rapidly displaced resident populations of Aedes aegypti mosquito. Both are important disease vectors. The native being considered the primary vector of breakbone fever — or dengue. And the Asian tiger mosquito recently emerging as the most important transmitter of chikungunya virus and yellow fever. By September 1986, the range of the Asian tiger mosquito had extended as far north as Utah. The demise of the native Aedes aegypti had already begun — representing not a transient ecological phenomenon, but the beginning of permanent colonisation, and resulting in rapid declines and extinctions of the native mosquito species.

Aedes aegypti originated in Africa and was introduced to the Americas between the 15th and 18th centuries, during the height of the slave trade and most likely on ships transporting slaves. They quickly established across the south eastern part of the US. Then what followed was a demise in the face of stiff competition and after centuries of habitation in America. An inadvertent metaphor for the “Post-America

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Predicting the next epidemic

Charles Ebikeme — Wed, 02 Jan 2013 00:15:21 +0000

In some parts of this world the rains predict disease, and a hot, dry, dusty wind is the harbinger of a meningitis outbreak that is yet to come. Now, from where you sit, Google will soon predict the next great epidemic.

At this time of year, ever since that 2009 paper was published on flu trends, seasonal influenza and how we predict it, is a recurring topic.

It seems we are always moments away from the next great flu epidemic. This year saw a novel coronavirus make the rounds. A virus that usually causes nothing more serious and common than a cold, was the source of severe respiratory illnesses in the Middle East, with reported cases coming from Qatar, Saudi Arabia and Jordan, and resulting in 5 fatalities.

The curious case of the novel coronavirus is a new strain of virus that has not been previously identified in humans. The hypothesis is that it jumped the species barrier, but, as of yet, a definitive origin has not been identified.

When a disease will decide to jump the species barrier is hard to predict. Some of the most serious afflictions of humans in recent times have had their origin in animal diseases. HIV/AIDS and ebola being the prime example. Seasonal influenza is another — causing tens of millions of respiratory illnesses and up to half a million deaths worldwide each year.

In mankind’s eternal struggle against disease, as the adage goes, prevention is better than a cure. But how do we prevent disease? How do we mitigate for an oncoming plague or pestilence? A part of this prevention is predicting it.

Currently, we can only really predict an epidemic when it is currently in motion. Hospitalizations are the only way we can really track a disease. When it is possibly already too late. When people are already sick.

In the week the world was supposed to end, the European Centre for Disease Control (ECDC) released its weekly report on influenza surveillance, like it had done since week 40 of this year. The report aggregates data on influenza-like illnesses reported in primary health care facilities, as well as virological and clinical data.

Flu surveillance, in Europe and similarly in the US, is based on nationally organised sentinel networks of physicians, mostly general practitioners (the first person you go see when you’re ill), covering at least 1 to 5% of the population in their countries. Each sentinel physician reports the weekly number of patients seen with influenza-like illnesses and acute respiratory illnesses.

The report is essentially there to tell us when a flu epidemic is going to break out. In week 49, ECDC announced that the season of influenza transmission had begun.

Along with the direct methods of detecting and monitoring disease, in recent years new and innovative non-direct methods have been tested. From sales of over-the-counter medication to online activity. The idea is to try and record health-seeking behaviour… ie before the disease has taken hold in a population.

Emergency hospital during influenza epidemic, Camp Funston, Kansas.

Monitoring disease, 140 characters at a time…

Flu is a disease very amenable to being searched and turning up in social media. Health-seeking behaviour — in this day and age, we google every ailment. However, diseases which are more serious probably won’t follow this social pattern.

The concept is essentially trying to “predict the present

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dengue – Australian Science

Invasion of the Asian tiger mosquito

Predicting the next epidemic