It is far from certain yet but it is believed the birth defect (microcephaly, meaning small head) which is occurring in large numbers in Brazil is being caused by a virus, specifically the Zika virus which is carried by a mosquito. One reason this is being suggested is that a similar virus, a cytomegalovirus, is known to cause microcephaly.
If this were limited to a few slums it might not be of much interest elsewhere but every indication is that the mosquito and the infection are both spreading at alarming rates to other countries and Zika has already been found in the U.S.
Pandemics
Nothing in our general experience demonstrates the inevitability of mathematics more dramatically than does a developing pandemic.
The mathematics behind a pandemic or epidemic are simple. Some diseases, especially ones where there is little immunity in the population, no vaccine, and is easy to spread, grow exponentially. Exponentially means the number of infected people essentially doubles every day.
No Threat To Most People
Zika is no more threat to the elderly, children or men, than the flu, probably less. It is only dangerous to pregnant women, and even then it doesn’t cause any severe symptoms in women; instead, it appears to cause severe birth defects, at least in the current South American epidemic it is thought to be the source of the birth defects.
Five Reasons Zika Will Be More Difficult to Control Than Ebola
There are five reasons why Zika will be more difficult to control than Ebola and therefore perhaps a much bigger threat.
- First, it is spread easily by a rapidly proliferating mosquito while Ebola spreads by exposure to bodily fluids from those who are infected. That makes Zika more like the plague which was spread by fleas.
- Second, only about 20 percent of those who have contracted Zika have any symptoms significant enough that they even know they have caught anything.
- Third, there has been almost no work on a vaccine and when a potential vaccine is developed it will have to be tested on pregnant women eventually, a very difficult proposition ethically since it would involve infecting the pregnant women.
- A fourth factor may be the biggest barrier to stopping the spread of Zika – it is most prevalent in tropical environments – perfect breeding grounds for the mosquito. Only DDT is thought to be both an effective and inexpensive insecticide that can control the mosquito population. Unfortunately, DDT is almost as dangerous to people as the Zika virus itself.
- Last we come to sex. Yes, it is possible to transmit Zika via sexual contact but It isn’t known yet how easy it is to transmit sexually.
The center of the new infection is Brazil, the location of both an enormous Mardi Gras celebration this February and the upcoming 2016 Olympics. Even a tiny percentage of infected visitors would spread it world-wide in a few weeks.
Getting Tired – Now the Really, Really Bad News
It is thought that a rapidly spreading Asian tiger mosquito, A. albopictus is also capable of carrying Zika which opens up vast new territories for potential spread of the virus.
This is not just another “bird flu panic” situation, it is much more like the actual Ebola threat except that it was relatively easy to stop Ebola – people with the disease quickly developed a fever and also quickly died which was terrible for them but great for those trying to prevent it spreading to the rest of the world.
According to Science Magazine, the tiger mosquito was first seen in Georgia in 1983 but by 2008 it was already becoming common in 32 states.
And in yet another case of unintended consequences, the recycling movement has been responsible for the mosquito’s rapid spread via used automobile tires which are practically designed to be breeding vessels for mosquitoes – if you’ve ever had one around the house you know they trap stagnant water.
Japan and Germany in particular have strict rules about reusing tire carcasses for recapping or storage/disposal so millions of used tires are annually shipped from Asia and Europe to the U. S.
You might think that colder climates would slow the spread of this tropical insect but not so. It turns out that the tiger, almost exclusively of tropical insects, is well adapted to overwintering because the eggs can hibernate in cold weather.
The tiger is very aggressive, so much so that in southern Italy it is actually reducing tourism which has, so to speak, come back to bite the Italians who failed to aggressively move to eradicate the tiger back in 1990 when it was discovered in a kindergarten in Genoa.
Zika Facts
But the big news today is about Zika so let’s take a closer look at that virus.
Zika can only be confirmed through PCR Polymerase Chain Reaction DNA analysis and, since most people don’t even know they have been infected, most people will never be tested.
Zika And Pregnant Women
Even worse, the test only works if conducted within a few days of the infection. There is no use testing a pregnant woman who was bitten by a mosquito three weeks or months ago, the test simply won’t show anything (except possibly a “false” positive which can happen with any test and is meaningless.)
That makes it extremely difficult to determine if the surge in reported cases of birth defects in northern Brazil are actually due to Zika.
No Treatment For Zika
There is no treatment for Zika, as is true for most virus infections; fortunately even people who have a severe infection with strong symptoms are hardly more inconvenienced than they would be with the common cold – that means that, other than the most vulnerable (elderly or otherwise weakened) individuals, few will require more than over-the-counter palliative treatments and if those are not available they will simply have a few uncomfortable days.
WHO Zika Warning
The World Health Organization which has called for an emergency meeting to discuss response to Zika reports, “People with Zika virus disease usually have a mild fever, skin rash and conjunctivitis. These symptoms normally last for 2-7 days.”
According to the WHO, the best (read ONLY) method of prevention is to avoid mosquito bites. Another birth defect has been linked to the virus, Guillain-Barre. Any time something is termed a “syndrome” you know that little is known about it. [WHO] [CDC]
