Posts Tagged ‘Laurie Garrett’

Even the best of us...smallpox, anthrax, influenza and the CDC

Wednesday, July 16th, 2014
This is our premier laboratory

This is our premier laboratory

The Center for Disease Control and Prevention, AKA the CDC, America's central medical laboratory has recently had multiple problematic episodes. I was trying to follow up on the vials of smallpox virus that were found in an old refrigerator that the FDA apparently had forgotten, The question, of course, was whether the virus samples were long dead or still viable. They had been sent to the CDC to have that highly significant issue resolved.

Since then there has been a followup announcement, but also several articles on significant issues with procedures and safety at the CDC itself. The first was published in The New York Times, AKA NYT, (as well as in other papers, but I get the NYT daily on my iPad , so saw it there first). The startling title was "C.D.C. Closes Anthrax and Flu Labs after Accidents." The current director of the CDC, Dr. Thomas Frieden, called the lab/agency "the reference laboratory to the world," but admitted there had been a series of accidents (actually lapses in set safety procedures), in the recent past, that were quite frightening.

A month ago potentially infectious samples of anthrax, a bacteria found naturally in soil and commonly affecting wild and domesticated animals worldwide, causing an extremely serious, but rare illness in people, were sent to labs that were not equipped to deal with them (anthrax would normally be handled only with the highest level of protective biosafety gear and procedures (BSL-4). The CDC also has a rather simplistic YouTube video discussing anthrax's use as a potential bioterrorism weapon, but in this case 62 or more CDC employees were potentially exposed to the bacteria in the course of their work.

The good news is it appeared nobody was in danger; all those employees were given the anthrax vaccine and also begun on antibiotics. The background information available online says there has never been person to person spread of the disease.

It appears that it's exceedingly tough to get rid of anthrax in the environment; I'll go over the classic historical example of how careful government researchers have been with its spores..

In the 1940s, British scientists used a small Scottish island (Gruinard) for germ warfare research. That island, thoroughly contaminated with anthrax spores, remained off-limits for forty+ years before extraordinary efforts, begun in 1986, rendered it safe for ordinary use. The surface of the island was only 484 acres; it was sprayed with a herbicide, then all dead vegetation was burned off. Next 200 tons of formaldehyde solution was diluted in 2,000 tons of seawater and sprayed over the entire island. Perforated tubing was used to ensure that 50 liters of solution were applied to every square meter being treated.

Later the effectiveness of the decontamination process was assessed by taking two duplicate sets of soil samples. Each was tested at two major government labs. Anthrax spores were detected only in "small quantities in a few places." These specific areas were treated in July 1987, followed by further soil sampling in October 1987. No further traces of anthrax spores were found.

Blood samples from local rabbits were also tested for anthrax antibodies. No such antibodies were found.

Following these measures, a farmer grazed part of his flock of sheep on the island for six months. The sheep were inspected monthly by the District Veterinary Officer, and returned to the mainland in October 1987 in excellent condition.

On April 24, 1990, 4 years after the decontamination works had been completed, a Defense Minister visited the island and removed the safety signs, indicating that the island had finally been rendered safe. Then, per agreement  the island was sold back to the heirs of the original owner for the WWII sale price of £500.

But a senior British archeologist said he still wouldn't set foot on the island; he was concerned because of potentially infectious particles found in some of his digs.

Yet another NYT piece, "Ticking Viral Bombs, Left in Boxes," this one written by a distinguished physician, Lawrence K. Altman, M.D. recalls the irony of the outcry for mass smallpox vaccination of our entire U.S. population after 9-11 (when no Iraqi supply of the deadly bacterium was ever located), contrasted with the recent finding of six vials, two with live smallpox bugs, being found in in Bethesda, almost within "spitting distance" of our center of government.

In 2011 the Birmingham Mail reviewed a tragic lab accident which led to the last known smallpox death . The city, now England's second largest, was a site of a medical research laboratory associated with the local medical school. Viral particles got into an air duct and a photographer whose studio was one story up from the lab became the last known case of active smallpox and died from the disease in spite of having been vaccinated twelve years before

Dr. Altman discusses the pros and cons of eradicating the last two known stocks of the virus, one at the CDC, the other in a Russian lab in Siberia. Even if the natural virus is finally and totally eliminated , a rogue group may well be able to re-establish their own supply from the known genetic sequence of smallpox.

Lastly I saw a NYT article with an even more disturbing title, "After Lapses, C.D.C. Admits a Lax Culture at Labs." CDC workers had somehow shipped a dangerous strain of avian influenza to a poultry research lab run by the Department of Agriculture. Known as H5N1, the virus had killed more than half of the 650 people who had been infected with it since 2003. Again there were no deaths from this mistake.

After all of this recent furor plus the historical examples, I'm heartily in favor of the idea that's been broached saying such dangerous organisms should be confined to a minimal number of labs and even those clearly need to tighten up their standards.

 

 

 

 

 

 

Cholera: Part two, the nearby 21st century epidemic

Tuesday, February 26th, 2013

Until 2010 I hadn't thought much about cholera in the modern era. I had considered it a disease from the past  and associated it with Dr. John Snow, the father of modern

Algae can carry cholera bugs a long ways

epidemiology , the study of the patterns, causes and effects of health and disease in defined populations (Hippocrates, the famous Greek physician is considered the ancient father of the field).

I was clearly wrong in doing so.

I had previously read parts of the science writer Laurie Garrett's first two books, The Coming Plague: Newly Emerging Diseases in a World Out of Balance published in 1994 and Betrayal of Trust: the Collapse of Global Public Health which followed in 2000. Her first book touches on cholera in Africa and then has a section on the seventh Global Pandemic starting in 1961 in Indonesia's Celebes Islands.

Now I read Chapter 16 of The Coming Plague in detail. It mentioned that Rita Colwell, PhD, an  environmental microbiologist, was convinced in the 1970s and 1980s that bacteria and viruses could be carried in algae, the world's  oldest living life form. Algae are responsible for "red tides"  (AKA Harmful Algal Blooms or HABs), episodes when those ocean plants massively increase in number then produce toxins making shellfish dangerous to eat and killing off fish.

Colwell found that the bacterium responsible for cholera could survive encysted in algae and float long distances in their "plant capsules." The El Tor strain of the bug was responsible for the 1991 epidemic in Peru. The CDC's publication Morbidity and Mortality Weekly Report, AKA MMWR, mentioned that outbreak in its February 15, 1991 editionMMWR noted this was the first appearance of cholera in South America in the 20th century and recommended exclusive use of boiled water for drinking, careful cleaning of fruits and vegetables, and avoidance of raw or inadequately cooked fish or other seafood. It stated the risk to U.S. travelers was low.

In the next eleven months cholera claimed over 330,000 victims in the Western Hemisphere, killing just over 1%. Lima, the Peruvian capital, had stopped chlorinating its water and Peruvians often ate ceviche, uncooked fish and shellfish mixed with lime juice. By the Fall of 1993, 8,000 deaths and over 900,000 cases of cholera were reported in Latin America. The El Tor strain of the cholera bacterium had become endemic in the region.

A 1994 article in the Journal of Clinical Microbiology documented the next chapter in the modern history of cholera. A new strain struck in December of 1992, first in the Indian city of Madras and then spreading to Calcutta, Bangladesh and Thailand. Even those who had previously been through a siege of cholera were not immune to the O139 strain as the Bengal cholera Vibrio was termed.

An earthquake can be both a disaster in itself and the seed for an epidemic.

The Western Hemisphere would have another cholera epidemic eight years later. In the January 10, 2010 a major earthquake in Haiti occurred. Although its magnitude on the logarithmic Richter scale was "just" 7.0, while the offshore earthquake in Japan in 2011 was an 8.9 (an 8.0 quake is 10 times as intense as a 7.0 and a 9.0 is 100 times as powerful), the depth of the Haiti quake was ~half that of the 2011 tremor in Japan and it struck a major Haitian city. The damage was immense and the local infrastructure was severely disrupted with healthcare, water and sanitation being affected.

A recent New England Journal of Medicine article (Feb 14, 2013) reviewed the surveillance efforts during the subsequent two years. Prior to the earthquake, less than two thirds of Haiti's population of 9.8 million had access to even the lowest category of an improved water source; less than an eighth drank treated water from a pipe system and only a sixth lived with adequate sanitation. The 1991 Peruvian cholera didn't reach Haiti so there was little or no prior immunity to the El Tor Vibrio strain.

The results were predictable, a major outbreak of cholera, but the government and international medical assistance markedly ameliorated the epidemic. Through October 20, 2012 over 600,000 cases of cholera were reported and 7,436 deaths resulted. The case fatality rate was initially high in some locales (4.6%), but within three months of the start of the epidemic it fall to the World Health Organizations target of <1.0%.

In comparison there were 2.8 million cases of cholera globally in 2011 with 91,000 deaths (3.25%). The CDC notes that twenty-three cases occurred in the U.S.; 22 were associated with travel to Haiti, one with consumption of food products from that country.

The treatment of cholera is relatively simple: the WHO says rehydration with oral rehydration salts is enough in almost all cases. Intravenous administration of fluids can be life-saving in especially serious cases.

But how about preventing the disease?  A Perspective column in the same journal edition (NEJM Feb 13, 2013) is titled "The Cure for Cholera--Improving Access to Safe Water and Sanitation." The three authors, all with dual MD, MPH degrees, note that the malady is still a major source of illness and mortality in the developing world with WHO estimating 3 to 5 million cases and 100,000 to 200,000 deaths a year.

In the treatment arena, they note that antibiotics should be given to those with even moderate dehydration, that all patients should receive zinc, which can decrease the duration of diarrhea, and a newer variant of the two-dose vaccine should get wider usage.

Safe drinking water and modern sewage disposal is still a major issue for many in 2013: two and a half billion live without adequate toilet facilities and nearly 40% in the least developed regions of the world don't have bacteria-free water to drink.

More than a billion of the poor and marginalized need help. But estimates of $50 billion needed per year are daunting in these tough economic times.