CONGO: Ebola attack seemingly over, for now (Cuvette-Ouest)

REUTERS ALERTNET ^ | 8-24-05

[Mother Abigail]

BRAZZAVILLE, 24 August (IRIN) - Although the government has not publicly declared the Ebola haemorrhagic fever over, medical authorities in the Republic of Congo say they have the situation well under control.

They said 10 people died in the April to July outbreak, the fourth since the virus that causes the fever first appeared in the country in November 2001.

At the end of the first outbreak in Cuvette-Ouest in April 2002, Ebola killed 42 of the 57 people who were recorded as having contracted the virus, WHO says.

During the second outbreak, in the same area, it killed mostly gorillas in sites close to the Odzala National Park, where there were 128 deaths of the 143 cases recorded.

It was during the second outbreak that animals were infected. The national coordinator of Project ECOFAC (The Forest Ecosystems of Central Africa), Jean Pierre Agnangoye, said 600 of the 800 gorillas of the Lossi Sanctuary died of Ebola.

Since 26 May, there has not been a single recorded death - prompting WHO to declare the disease epidemiologically finished.

First, foreign scientists say they need to know where the virus hides. Dr. Jean-Vivien Mombouli, the technical adviser at the Minister of Health and the Population, said.

"Bats appear to be suspect number one," he said.

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BATS

{Dr. Robert Swanepoel is the leading voice in this hunt. Here are his newly published comments (8-30-05)}

Dr. Robert Swanepoel, consultant to South Africa's National Institute for Communicable Diseases, says researchers there have been researching the bat theory, both for Ebola and for Marburg. He explains the research is in its early stages and remains inconclusive.

Dr. Swanepoel describes what researchers discovered while investigating an outbreak of Marburg in the Democratic Republic of Congo that killed 128 people.

"And, we, ourselves, found evidence, nucleic acid -- we haven't published this yet - but we did find nucleic acid in, in other words genetic material of the Marburg virus in bats in a gold mine in northeastern DRC, where there was an outbreak of Marburg from October 1998 until September 2000, in this mine," Explained the doctor.

He said researchers tracking the path of infection were able to link people who were infected with someone who had worked in the mine. "Every time, one (researchers) controlled the chain of transmission within a family, the father would get sick in the mines, and then the wife, and so forth. You would control that, and then, there would be another outbreak in a week or two," explained Dr. Swanepoel.

"We found these were different strains of the virus, if you could call them strains. We found they were all picking it up in a gold mine. The mine flooded and the disease disappeared. So, that brought us nearer to the idea of bats."

Outbreaks of Ebola seem to have strong connections to forested areas, with those infected first in an outbreak having spent time in a forest, or having eaten a monkey found dead in a forest. Dr. Swanepoel says that, once again, the local research suggests bats could play some sort of role.

"Way back in 1996, we, ourselves here, infected a whole lot of different animals, which we believed were potential hosts, and even plants and so on, with Ebola," he said, "and we found that ... fruit and insect bats were able to replicate high levels of virus in their circulation, and not succumb to any disease that we could determine."

Dr Swanepoel emphasizes the research is inconclusive......(yada yada we don't really know etc...)

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IS EBOLA A NEW AND UNIQUE EVENT OR IS IT A REOCCURING PROBLEM FOR THESE AREAS? (Old events, long studied data, newly published results for peer review)

The Journal of Infectious Diseases 

Low Seroprevalence of IgG Antibodies to Ebola Virus

Richard T. Heffernan

A population-based serosurvey was performed to determine the seroprevalence of antibodies to Ebola virus (EBO) in a region that has experienced multiple epidemics of EBO hemorrhagic fever. Of 2533 residents in 8 villages, serum samples from 979 (38.6%) were tested by enzyme-linked immunosorbent assay for immunoglobulin (Ig) G and IgM antibodies to Ebola-Zaire (EBO-Z) virus.

Fourteen samples (1.4%) were found positive for IgG antibodies, and 4 of these (.4%) were samples from survivors of an epidemic of EBO hemorrhagic fever.

Seroprevalence based on the remaining 10 IgG-seropositive individuals with no history of exposure to EBO was 1.0% (exact binomial 95% confidence interval, 0.5%1.9%).

No serum samples were found positive for IgM antibodies to EBO-Z virus. The low seroprevalence suggests that, outside of recognized outbreaks, human exposure to EBO in this epidemic zone is rare.

(NEW BUG TO HOST - MA)

[Mother Abigail]

Dr. Swanepoel's comments can be found here:

Ebola, Marburg Viruses Continue to Elude Medical Breakthrough

The abstract of Dr. Heffernan's work can be found here:

Low Seroprevalence of IgG Antibodies to Ebola Virus in an Epidemic Zone: Ogooué-Ivindo Region, Northeastern Gabon, 1997

[Mother Abigail]

FYI

[Doctor Stochastic]

That's good news.

What ever happened in Angola though? I never heard.

[Mother Abigail]

As we previously discussed, the outbreaks seem to be seasonal.

We are trying to build a case where the bats and the great apes might come into contact during the time when a fruit tree is ripe.

We know that Insectivorous bats, Tadarida pumila, and fruit bats, Epomophorus wahlbergi, support Ebola virus replication without dying.

Furthermore, serum Ebola titers in infected fruit bats reached as high as 10,000,000 fluorescent focus-forming units per milliliter, with their feces containing viable Ebola virus.

It is still conjecture, but the dots are starting to close.

MA

[Doctor Stochastic]

Are you looking at the bats themselves, or their food as a potential resevoir? (Maybe both?)

[united1000]

Ebola, Marburg vaccines work in monkeys 9-2005
Date: Saturday, September 03, 2005 4:26 PM



Ebola, Marburg vaccines work in monkeys
WINNIPEG, Manitoba, June 5 (UPI) -- Canadian and U.S. researchers have developed vaccines against the Ebola and Marburg viruses that have been effective in non-human primates.

Scientists from the Public Health Agency of Canada with assistance from the U.S. Army Medical Research Institute of Infectious Diseases report that the vaccines have proven 100 percent effective in protecting monkeys against infection from the often deadly viruses.

The study, published Nature Medicine, says demonstrating that these vaccines are safe and effective in monkeys is a promising indicator of their real potential for use in humans.

"In addition, the vaccine targets dendritic cells, which are the same cells that Ebola and Marburg attack," said Dr. Thomas Geisbert of U.S. Army Medical Research Institute of Infectious Diseases in Frederick, Md. "These cells are also important in generating a protective immune response. So the vaccine goes exactly where we want it to go."

This is the first vaccine system that has protected nonhuman primates from both Ebola and Marburg, according to Geisbert.

Copyright 2005 by United Press International. All Rights Reserved

[EternalHope]

Very interesting. Thanks for posting.

[Mother Abigail]

As of Tue 23 Aug 2005, the Ministry of Health in Angola reported a total of 374 cases, including 329 deaths (Case Fatality Rate 88 percent) countrywide. Of these, 368 cases, including 323 deaths, were reported in Uige Province. A total of 158 cases have been laboratory confirmed.

52 contacts are being monitored in Uige Province, and clinical specimens from alerts continue to be shipped to the Special Pathogens Program, National Microbiology Laboratory, Public Health Agency of Canada, for diagnostic testing.

The last confirmed case of Marburg died on Tue 21 Jul 2005 in Songo municipality, Uige Province. There have been no laboratory confirmed cases since then.

[Mother Abigail]

The most likely scenario, at this time, goes like this;

Fruit trees become ripe and draw both the fruit bats and the great apes, a bat harboring the virus leaves droppings on the fruit which the ape then handles/eats.

The ape becomes infected, other apes become infected from contact with the index case. Bush meat hunters come in contact with the sick/dead primate - spreading the virus to their village.

There is no hard proof of this vector at present, but lots of very bright people are trying to prove/disprove the above hypothesis.

MA