Wednesday, August 19, 2015

Explaining Emerging Infectious Diseases

“2015 was a very busy year for emerging infectious diseases.”  -  Steven Hatfill, MD

Dr. Steven Hatfill
Photo: Wikipedia
Dedicating his lecture to Médecins Sans Frontières, for their heroic actions in West Africa, Dr. Steven Hatfill spoke to a captivated audience at the 33rd Annual Conference of Doctors for Disaster Preparedness in California about the 43 newly emerging infectious diseases that jumped to a larger geographic area from their wild animal hosts to human populations in the past 30 years.

He described the contributing factors:

-          The expanding global human population (doubled in southern Africa in the last 20 years)

-          Breakup and destruction of animal habitat

-          Scarcer food sources forcing animals to move closer to human populations

-          Intensive domesticated animal breeding causing viral mixing from “wild cousins”

-          Changes in animal migration and viral reservoirs (Ebola has 3-4 mutated virus strains)

-          New contact with humans

Dr. Hatfill spoke of the 2014-2015 Ebola virus outbreaks in West Africa, as a “complete mismanagement of a disease at the national and international level,” with no vaccine or definitive treatment yet.  He cited numerous risks that contributed to this large Ebola outbreak across three countries:

-          Consumption of bush meat since protein is scarce; contact with wild animals exposes human microscopic skin abrasions to fresh animal blood

-          Funeral attendance of victims

-          Contact with patients

-          Laboratory accidents with infected animals or tissue

-          Infected paper money (“lab experiments have shown that Ebola virus can remain viable for hours on currency”)

-          Contact with three species of fruit bats, possibly several species of insectivorous bats

-          Bat guano (it is suspected that viruses in aerosols decay quickly with the exception of “Marburg virus that can last hours in the air;” guano can act as a protective surface; it is likely that bat droppings contained the live virus)

-          Pigs as possible reservoirs that could carry Ebola Zaire  

-          Antelopes have been found to carry Ebola virus

-          Monkeys

-          Dogs with serum-positivity

Dr. Hatfill explained that the epidemic is likely to continue or resurface if three safety steps are not followed:

-          identify and isolate confirmed and suspected cases

-          contact tracing – who came in contact with whom and isolate the cases

-          safe burial practices (burials are highly infectious due to tribal washing and handling of the dead body)

The start of the Ebola outbreak in West Africa was traced in December 2013 in a village in Guinea. Children found some bats, a treat for locals, brought them home on Christmas Day. The epidemic started when a two-year old died after consuming the meat. His sister died nine days later, then the mother who was seven-months pregnant. “We’ve never had a case of a pregnant woman survive the Ebola infection,” said Dr. Hatfill. The grandmother who cleaned the hut became ill and sought treatment in another village, spreading the virus.

The disease spread silently over three months and killed 50 people. It was recognized and announced in March 2014 as an Ebola outbreak.  The Guinea Ministry of Health informed the World Health Organization (WHO). Dr. Hatfill opined that, because “Guinea had no idea how to respond,” Doctors without Borders came to the rescue and set up a field hospital in the middle of the 15-village outbreak area.

Sunlight inactivates the virus rather quickly in an open air field hospital, naturally ventilated, with high air flow exchange and high ambient humidity.  Viruses do not like high ambient humidity. Trees surrounding an Ebola field hospital/treatment center must be cut down so that bats cannot nest in them.  

“WHO had no idea what to do.” Doctors without Borders informed WHO that “this epidemic is unprecedented,” but the Ministry of Health said that the “doctors were overreacting and intentionally underreported the death count for political reasons,”  Dr. Hatfill added.

He described how, when the epidemic spread to a city of 2 million inhabitants, family members panicked and left their loved ones in the streets. Cases appeared in Sierra Leone by March 2014. A witch doctor died on April 8. A traditional burial was held for this highly respected healer. In the process, hundreds touched her, and this triggered a chain reaction of Ebola. “WHO was nowhere to be seen.” When nurses and doctors started to die in the hospital, MSF was called in. They found no list of patients, of villages, no contact tracing system, no surveillance system.”

By July 2014 the virus reached Monrovia, Liberia, with a total death toll of 800. When rumor spread that doctors were killing patients, a riot ensued on Day 83 of the outbreak, but no emergency was declared for fear of mass panic.

Two infected American missionaries were brought back to the U.S. via an isolator. “The transport team did not appear that they wore positive-pressured suits…  The CDC response was unsafe,” Dr. Hatfill added. The special unit at Fort Detrick, that could have evacuated sick people from anywhere in the world in case of an infectious outbreak such as Ebola, had been dissolved as part of the Obama budget cuts, he said.

“When I heard Anthony Fauci say that a single layer of gloves is sufficient for protection, it was clear to me that Ebola had become political.” Public statements about fever, thermal scanners placed at airport were not realistic, Hatfill said, because a study of the outbreak showed that 12.9% of cases never ran a fever.

He asked rhetorically, what if someone coughs into your eyes. You are going to get infected. How much Ebola virus is actually shed by an infected person via tears, sneezing, coughing, saliva, body secretions, and blood?  Skin contact with an Ebola patient is enough to infect someone else. Skin cells in the lab document infection, but “the time of infection is not well documented, we are not really sure when the virus is shed from skin.”

“As little as ten Ebola viruses can cause an infection, in some cases I think it’s down to one or two.” Dr. Hatfill added that “a year later, the doctor who recovered, still has Ebola virus in the humor of his eye.”

Having spent $120 billion on domestic preparedness, we could not even handle three Ebola patients without major drama, Hatfill said. “Respirators are now necessary to handle Ebola cases. Why do you need respirators if the CDC says that it is not spread by aerosol?” The three patient cases in the U.S. resulted in 10,000 contact tracings.

By the time the West Point slums of Monrovia were affected, the new Director of WHO, Margaret Chan, declared an emergency but the response was the typical “unprepared bureaucracy.”

U.S. Army was deployed to Liberia 10 months after the outbreak. The goal was to train local burial teams, control infection, and build multiple treatment centers. By October 2014 cases began to drop in Monrovia. “The disease started to plateau off.”

A Brand Acyclovir by Gilead was given to the three American patients, a drug that Dr. Hatfill said he took himself for monkey pox and has suffered no ill effects from it.

He reported that the death toll status as of July 2015 was around 12,000, with more than 20,700 people infected since the outbreak began. “We are still seeing new cases weekly in Sierra Leone and Guinea and six out of ten of these cases will die.” A promising vaccine seems to work.

There were many other emerging disease outbreaks that took place but were overshadowed by the Ebola outbreak:

-          Influenza A, transmitted by birds and pigs (China is the center for new influenza strain production, he said, because of their dense agriculture in which they raise pigs with ducks and chicken, causing wild virus mixing and recombinations between human, avian, and swine; CDC gets samples each year and tries to predict which strain will go pandemic; “sometimes they get it right, sometimes they miss it; this is where your annual flu vaccine comes from and it takes six months to make enough vaccine for everyone;” treatment with Tamiflu and Relenza can help but there are drug resistant strains)

-          Migrating birds from the south pole to the north pole help spread emerging viruses

-          2014 saw two new strains of pathogenic Avian flu, H7 and H9

-          2015 a large outbreak of Avian flu in the U.S., H5 and H2,  in Oregon  killed 40 million turkeys and chickens, affecting 10% of the U.S. supply

-          The flu pandemic of 1918 killed 50-100 million people worldwide, about 3-5% of the world’s population; the world’s population is now 5 times what it was in 1918 - a virus with that virulence could kill today  over 300 million people

-          19 Megacities in the world; 2 billion people live in shanty towns yet most cities have 72 hours of fuel, water, and food for inhabitants totally dependent on agriculture, transport, and delivery; fuel supply is also made through a very complex delivery system; based on calculations of chaos theory, a catastrophic collapse resulting from 30% loss of the workforce from disease could result in catastrophic failure of everything;

-          Animal die-offs , i.e., West Nile virus outbreaks in the 1990s (dead crows), avian cholera (birds drop from the sky during migration), antelopes in Kazakhstan died at the rate of 40% in two weeks, 100% mortality among infected flocks

-          2015 outbreak of the Bourbon virus

-          Enterovirus D68 with 691 cases of polio-like disorder, coincides with the illegal children bussed into the U.S.

-          Vibrio vulnificus from raw oysters in the Gulf of Mexico

-          Tick born virus infections

-          Chikungunya fever  in the Philippines (the virus comes from Africa via mosquitoes)

-          Porto Rico virus from mosquito bite

-          Corona virus in South Korea outbreak

-          Legionnaires disease outbreak in the South Bronx in 2015 from contaminated air conditioners

-          2015 amoeba in New Orleans water supply in St. Bernard Parish  

-          353 Orangutans in Philippines were serum-positive for Ebola Zaire and six of those were serum-positive for Marburg virus; bats from Bangladesh were carrying the same African strain of Ebola virus

Why is the Ebola virus more widespread than we thought before? Possible causes include:

-          Population has doubled in the last 27 years in Africa but the infrastructure has not matched the growth, causing extreme overcrowding in African cities

-          poor public health

-          dysfunctional government at all levels and chaos (doctors ran away)

-          slow and improper response to a crisis

-          WHO was training their own small staff, not local doctors in hospitals

-          Problems with body disposal, hut decontamination, surveillance alert, patient identification, patient isolation, patient swabbing, bagging dead bodies correctly, safe burial procedures

-          Village contact protocol (waiting at the edge of the village to be noticed and for a tribal rep; “you can’t just walk into the village, they will kill you”)

Dr. Hatfill asked rhetorically if we are prepared for a biological attack if we can hardly handle emerging disease outbreaks. Do we have the facilities and the necessary personnel to handle mass casualties? Sequestration under the Obama administration, he said, scaled back work that would have involved hot spots of emerging diseases and epidemiologists with gun training to be inserted rapidly into infected areas.

Hospital trains were used in time of war with operating rooms on board but have been discontinued. We could have one on the west coast and one on the east coast.  He concluded, for $25 million we can handle 10,000 patients and severe ICU cases for multi-purpose disasters such as earthquakes, hurricanes, and emerging infectious disease outbreaks.


















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