Monday, June 06, 2005

ENV: Monkeys immune to Ebola

All right. This is an ID victory. Intelligent Design at work, with man being the Intelligent Designer, using a wealth of knowledge of Darwinian-style evolution. The result? Vaccines for monkeys to protect them from two violent hemorrhagic fevers, Ebola and Marburg.

I think it's time to co-opt ID and make man the intelligent designer of advances in practical science based on evolutionary fact. Let them find another cute buzzphrase to sell their quackery.

From The New York Times

New Vaccines Prevent Ebola and Marburg in Monkeys
By DENISE GRADY, June 6, 2005


Scientists trying to develop vaccines against Africa's deadly Marburg and Ebola viruses are reporting an important milestone, a new type of vaccine that prevents the diseases in monkeys. Successfully immunizing monkeys is an essential step toward producing human vaccines.

Two new vaccines, one for Marburg and one for Ebola, were 100 percent effective in a study of 12 macaques being published today in the journal Nature Medicine. Monkeys given just one shot of vaccine and later injected with a high dose of virus did not even get sick. Normally, all the animals would be expected to die.

The Marburg and Ebola viruses are closely related, and in both people and monkeys they cause hemorrhagic fevers that can be fatal within a week. There is no vaccine or treatment for either disease. Death rates in people can be high, sometimes exceeding 80 or 90 percent.

Angola, where a Marburg epidemic was first detected in March, is still struggling to contain the disease, which has killed 340 of 408 victims. The virus is spread by contact with blood, saliva, vomit or other fluids from sick patients.

The two new vaccines are still experimental, and will not be ready to be tested in people for at least two years. If human trials are successful, products might be ready for licensing five or six years from now, the researchers said. The vaccines would not be used for routine immunization, but would be given to health workers in high risk areas, virus researchers and people who had been exposed to the disease, such as relatives and others in close contact with sick patients. Eventually, it might be possible to combine the vaccines to protect people from both diseases with a single shot.

The new vaccines are not the first to protect monkeys. An earlier one, first proved in 2003, may go into safety studies in people in the United States later this year. Each vaccine has its advocates, and researchers say it is advantageous to have several candidates on the horizon.

The work described in Nature Medicine today was done by scientists from the United States and Canada, led by Dr. Steven M. Jones and Dr. Heinz Feldmann of the Public Health Agency of Canada in Winnipeg, and Dr. Thomas W. Geisbert of the United States Army Medical Research Institute of Infectious Diseases in Fort Detrick, Md.

Dr. Jones said the goal of the research was to provide a vaccine that could be used to stop outbreaks like the one in Angola or to protect people from germ warfare. He and other researchers said that governments and the military developed a strong interest in making vaccines against Ebola and Marburg during the 1990's after a Soviet defector said that Russians had stockpiled the Marburg virus, weaponized it and packed it into warheads for possible use in attacks on cities or battlefields.

"Marburg and Ebola are not as significant threats as smallpox would be, but one could wreak incredible human health tragedies in this country and could probably create a huge economic burden even if the diseases didn't spread like wildfire," said Dr. Peter B. Jahrling, an author of the article and an expert on viruses and bioterrorism who used to work for the Department of Defense and is now a chief scientist at the National Institute of Allergy and Infectious Diseases, of the National Institutes of Health. "But I think a lot of people here also see the humanitarian aspects of providing vaccine to people who need it."

Dr. Cathy Roth, head of the emerging and dangerous pathogen team at the World Health Organization, said: "This work is very interesting, very exciting and very promising. There's a long way to go before this vaccine could be put into people. But we really do hope it is pursued."

To make the vaccine, the scientists used another virus, V.S.V., for vesicular stomatitis virus, which causes a mouth disease in cattle but rarely infects people. They chose it because it has a similar genetic structure to the Marburg and Ebola viruses, and because other researchers have had success with it in developing vaccines.

They altered V.S.V. by removing one of its genes - the change makes it harmless - and replacing it with a gene from either the Marburg or Ebola virus. The transplanted gene forced V.S.V. to produce Marburg or Ebola proteins on its surface. The proteins cannot cause illness, but they provoked an immune response that protected the animals.

The monkeys were housed at a high-level biohazard laboratory at Fort Detrick, where the researchers, wearing space suits, watched them intently for signs of illness after they were injected with Marburg or Ebola.

"By Day 6, I have a very good idea of whether it's going to work or not," Dr. Geisbert said. "On Day 6 I was feeling really good. By the time we get to Day 10, if the animals haven't become sick or had any problems, we pretty much know it's worked. It is an incredibly good feeling. All the people on the team are high-fiving. I was communicating with Heinz and Steven every day, two and three times a day. 'How are the monkeys? How are the monkeys?' "

As the team pursues its research, other scientists are moving ahead with the previously developed Ebola vaccine, based on an inactivated version of another type of virus, an adenovirus, which can cause common cold symptoms in people. That vaccine, tested in 2003, also protected monkeys, and studies in people may begin this year.

Dr. Jahrling, who has worked on both types of vaccine, said the government was paying for both approaches to cover its bets. He said he thought a vaccine based on an adenovirus would be ready before one based on V.S.V.

"They've got a runner on third with that one," he said, "and the other guys have a runner on first."

Dr. Jahrling added: "A little competition is good. It accelerates everybody. If nobody's behind them they kind of slow up."

But Dr. Gary Nabel, head of the Vaccine Research Center at the N.I.H. infectious disease institute, who has been working on the adenovirus vaccine, said: "I don't look at it as a race. For me, the adversary is the virus and whatever gives us the best opportunity to defeat the virus is what we need to go with."

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