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has 2 comments by DaveW:
Aedes aegypti and to a lesser extent Aedes albopictus are the primary vectors of dengue, zika, yellow fever, and other nasty arboviruses. Both are weed mosquitoes carried around the world by people and living around people breeding in accumulations of water in pots, tanks, garbage, old tires etc. We could easily eliminate them with a concerted effort. Even before World War II, and with no DDT or any other useful insecticide, public health officials were able eradicate Aedes aegypti from areas along the Gulf Coast just by vigorously enforcing sanitation and treating tank water. What the World lacks is the political will (wherever halfwit environmentalism has taken hold) and functional public health organisations elsewhere. Apparently even totalitarian Cuba can't control their arbovirus vectors.
The southern US is broadly infested with the mosquito vectors of dengue and other nasty arboviruses. They keep popping up in California too. The reservoir of dengue is people with an active infection of the virus. Put some people with the virus circulating in their blood into a neighbourhood with populations of the mosquito vector and just wait. That's what happens every year in northern Queensland and the Northern Territory in Australia. The solution is not vaccinating hundreds of millions of people for all the various strains of dengue (last I heard there were 7), zika, yellow fever etc. with the same vectors and reservoirs. The solution is to eliminate the vectors. This would take far less effort than eliminating polio or small pox or the Guinea Worm and we have all the tools we need right now. The mosquito vectors are only two species and both live around people and sanitation is one key strategy. What we don't have is any governments that really care enough to make the effort (and also a millstone of anti-science environmentalists to block any efforts made). •Reply•Share ›
NYTimes article mentions the problem in the Philippines
The illness, also called breakbone fever, can be excruciating, with high fevers, headaches, muscle and joint pains, and lingering weakness.
A second infection of dengue can lead to a severe form of the disease, which can cause hemorrhage or shock and can be fatal.
An estimated 400 million dengue virus infections occur around the world, and there are about 500,000 cases of the severe form, dengue hemorrhagic fever, which causes about 20,000 deaths, according to the C.D.C. No drugs are approved to treat dengue disease.
According to the C.D.C., most cases of dengue fever in the 48 contiguous states were acquired elsewhere by travelers or by immigrants, although some isolated outbreaks have occurred, such as in South Texas in 2005. Dengue is endemic in the United States territories of American Samoa, Guam, Puerto Rico and the Virgin Islands.
“I think the message is that this is such a serious disease that we need to have something,” said Vincent Racaniello, a professor of microbiology and immunology at Columbia University.
He expressed concern that the vaccine’s acknowledged risks could worsen broader — and unfounded — skepticism about vaccines, which is fueling a separate global outbreak of measles. “This is going to give them more ammunition,” he said. “They can take this and say look, we are releasing a vaccine that is known to have issues.” In the Philippines, childhood vaccinations against measles dipped in the aftermath of the uproar over Dengvaxia, contributing to an outbreak in that country that has led to more than 400 deaths since January, according to a report this week by Unicef and the World Health Organization.
NPR notes the problem with the vaccine:
That shot launched a massive vaccine campaign to inoculate nearly 1 million schoolchildren with Dengvaxia. The goal was to save thousands of kids' lives and prevent an estimated 10,000 hospitalizations over a five-year period. But in the end, estimates are that more than 100,000 Philippine children received a vaccine that health officials say increased their risk of a severe and sometimes deadly condition. I
n addition, other children who received the vaccine may have been endangered because, their parents alleged, they were not in good health.
the French pharmaceutical company Sanofi Pasteur spent 20 years — and about $2 billion — to develop Dengvaxia. The company tested it in several large trials with more than 30,000 kids globally and published the results in the prestigious New England Journal of Medicine.
But halfway around the world from the Philippines, in a Washington, D.C., suburb, one scientist was worried about the new vaccine. "When I read the New England Journal article, I almost fell out of my chair," says Dr. Scott Halstead, who has studied dengue for more than 50 years with the U.S. military.
When Halstead looked at the vaccine's safety data in the clinical trial, he knew right away there was a problem. For some children, the vaccine didn't seem to work. In fact, Halstead says, it appeared to be harmful. When those kids caught dengue after being vaccinated, the vaccine appeared to worsen the disease in some instances.
Specifically, for children who had never been exposed to dengue, the vaccine seemed to increase the risk of a deadly complication called plasma leakage syndrome, in which blood vessels start to leak the yellow fluid of the blood. "Then everything gets worse, and maybe it's impossible to save your life," Halstead says. "A child can go into shock." "The trouble is that the disease occurs very rapidly, just in a matter of a few hours," he adds. "And there's nothing on the outside of the body to signify the person is leaking fluid on the inside."
The complication is rare, says Halstead. Still, he was so worried about the safety concerns that he wrote at least six editorials for scientific journals. He even made a video to warn the Philippine government about the problem.
FDA article here.
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