Sunday, August 1, 2010

Hot Winters in Queensland

Surprisingly, I made it home from my vacation. I say this, because from the moment I booked my flights, I began looking up stuff that could possibly kill me that are specific to Australian territories. My boss tried to scare me (me? really? nice try.) by talking about the deadliest snakes in the world, and constantly looking up photos and youtube videos of the golden orb weaver spider. Unfortunately for her, those types of things don't scare me at all. I, of course, was on a hunt for much...smaller things!

All in all, Australia was a blast! I highly suggest it for anyone who is looking to travel, and travel cheap. Their winter months are from May to November, so not only was tourist season nowhere in sight, so were all the things I wanted to discover. It was too cold for marine stingers (jellies), it was too cold for (most) mosquitoes, and in the end, the scariest thing I was up against was cold/flu season. Disappointing!

In my hunt for deadly pathogens (whilst on vacation, nonetheless), I discovered some interesting facts about Australia's health, as a country, a continent and an island!



It turns out, in 2003, Northern Queensland had an outbreak of Dengue Fever, which survived through the winter months. This is surprising because Dengue Fever is a viral pathogen that is transmitted by mosquitoes as they take bloodmeals from human hosts, who usually only reproduce in the summer months due to the comfortable environmental conditions. Since 2003, Queensland health officials have taken it upon themselves to control Dengue Fever through the use of health education and insecticide sprays to kill any mosquito populations near residential communities.

In 2009, Cairns reported over 900 cases of Dengue Fever. The 2003 outbreak was primarily concentrated in Townsville, which happened to be the first stop on my itinerary.



Queensland coastal cities are known for their beach-town attitude, their easy access to the Great Barrier Reef, and their great weather year round. Apparently, they are also known for their propensity for Dengue Fever outbreaks. If you are interested in epidemiology, here is a nifty table that reports Queensland cities and their infection rates over the past 10 years.



What really is Dengue Fever, you ask?

Dengue Fever is a class IV virus in the Baltimore classifications system, which means its a positive (+), single stranded RNA virus that uses negative (-), single stranded RNA as its intermediate before interacting with the host's mRNA. Don't worry, it's not that difficult. Here, let me explain further:



Paul Ahlquist's article Parallels among positive-strand RNA viruses, reverse-transcribing viruses and double-stranded RNA viruses provides a very nice illustration (see the middle panel, or, b.) of positive-strand RNA viral replication. As you can see, the originally infecting virus (entering at the top) is carrying positive (+), single strand viral RNA. Once that viral RNA is released into the host's cell, it interacts with a series of replication proteins which begins the genomic replication cycle, using the original viral RNA strand as a template. Some negative (-) single stranded viral RNA is created as an intermediate, in order to create more positive (+) RNA. 

Dengue Fever is a part of the Flavivirus genus, which also encompasses the West Nile virus, Yellow Fever, and other viruses that can cause encephalitis. Dengue can cause symptoms that are more mild in children than in adults, such as high fever (from 104-105 degrees Fahrenheit, in some cases) with at least two of the following: severe headache, severe eye pain, joint, bone or muscle pain, a rash, low white blood cell count, and a mild bleeding manifestation (from nose or gums, or easy bruising). The joint, bone and muscle pain is said to be so excruciating that it feels as if your bones are literally shattering inside of your skin.

Now, they often monitor Dengue patients closely to see if their symptoms increase in severity. If there is an increase, it can be an indication of Dengue Hemorrhagic Fever (DHF), which can destroy tissues and cause suffering patients to "bleed out" (much like the symptoms of Ebola, as written about here). The more severe symptoms that put patients on a close watch are severe abdominal pain and persistent vomiting, red spots or patches on the skin, bleeding from nose and/or gums, vomiting blood, black and tarry feces, pale, cold and clammy skin, drowsiness and irritability, and difficulty breathing.


Unfortunately, there is no treatment for Dengue or DHF, but there have been advances on how to ease symptoms and decrease the mortality rate for people suffering from DHF.

Dengue Fever is rare in the United States and other non-tropical areas, but there have been minor outbreaks in the past. In the past few months, an outbreak surfaced in Key West, FL, infecting 28 people. Here is an interview with one of the women who was affected. In this article, the CNN reported writes about Rick Branch, a U.S. Navy officer stationed in Key West, who was among the first cases to be confirmed after the woman in the article. The reporter has the interest to write about Rick's symptoms and experiences, but leaves some major points out. Check it out:

"It felt kind of like a hangover -- though I wasn't drinking the night before," [Rick] says. "I had a foggy head. I was a little bit tired."

Three hours later, Branch was freezing cold and had a fever. By Tuesday his joints were getting sore, and by Wednesday the pain was excruciating. "I could barely walk straight because the joints hurt so bad," he recalls. "They don't call it breaking-bones for nothing."


He had also developed a rash, and by Thursday his gums were bleeding. "I was hemorrhaging," he says."

Ok, that's all normal reporting. Symptoms, personal quotes. Let's ask Rick what he did about it, right?

"Although Branch and his wife had looked up his symptoms on the Internet and began to suspect dengue fever, it wasn't until he was flown to Miami and saw four doctors there that dengue fever was seriously considered."

 So, Rick took his own health seriously, and went and did his research. Granted, the internet doesn't always give you the right information, but if you are using credible sources, then its a worthwhile effort. Rick suspected it was Dengue Fever and due to its rarity in the area, the doctor's dismissed the idea.

For some reason, that truly bothers me. I have had this very situation (well, minus the Dengue), and I was misdiagnosed and shuffled out of the doctor's office with a nice pat on the head. I'll be the first to admit, I am a total hypochondriac, but in a curious way that has always had good intentions. I expect my doctor's to work with me, not assume I'm an idiot, and I'm sure Rick would have appreciated the same courtesies. When it comes down to it, Rick could have died if his hemorrhaging was not taken seriously. Luckily, he didn't.

 And, as always, the press is doing a great job making everyone paranoid and mislead. This article is a perfect example:
MOSQUITOES CARRYING DENGUE FEVER CAN LIVE INDOORS.

NO WAY! Are you kidding me? This article makes me want to repeatedly slam my head in a door.


"When a Palm Beach County family was plagued by a swarm of little black mosquitoes, county mosquito chief Ed Bradford knew to look for Aedes aegypti hiding in the house.

"They were in the Waterpik," Bradford said. "The family hadn't used it in a while, I guess, and there was a little water left in it."

A Broward County family had Aedes in their bottled water system. Another had them in the overflow tray under a refrigerator water dispenser, said Broward mosquito biologist Evaristo Miqueli."

Seriously? in your WaterPik? Thank you, Miami Herald, for another great piece of journalism.
Step one to avoiding Dengue Fever: clean your house.




Here is another great article on the increase of infectious diseases in Australia, not just dengue rates.

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