Friday, August 21

Part 3, Dealing with H1N1 swine flu outbreaks in U.S. schools: CDC advice about non-medical strategies and what's wrong with it

There has been bad news on the swine flu front since I last posted. On August 17 the CDC announced that the 120 million doses of swine flu vaccine they were expecting for delivery in mid-October had been chopped to 45 million doses.

I'll discuss the situation in more detail later in this post; for now, the delay in vaccine deliveries means that the regular flu season in the USA will be in high gear by the time the nation's schoolchildren are vaccinated against swine flu in appreciable measure. If the flu season is marked by a high incidence of swine flu infections, the choices facing parents and school administrators are very narrow.

I won't sugar-coat this: the ship left the pier in March when the CDC initially made the wrong call on how to handle the swine flu outbreak. Since then the choices have gotten increasingly unpalatable.

The American public, including school administrators, was never explicitly told certain things about the 2009 swine flu viral infections. The information missing from the nightly news was out there, on the internet, and I've discussed in on my blog. But it was not until the 21st (Singapore time) that a mainstream reporter, Bloomberg's Jason Gale, pulled together many bits of data to deliver a bleak picture of the swine flu outbreak:

Yes, the death toll from swine flu is relatively low, although I stress that "relatively" in this context is a matter for heated debate. But the catch is the way the 2009 swine flu attacks those who become seriously ill with the infection:
In some patients, the virus causes such a severe assault on the respiratory tract that the lungs become inflamed and the grape-like sacs where gas is exchanged are injured, causing bleeding and a critical loss of oxygen supply.(1)
Jason's report details that saving those patient's lives, which can require highly specialized procedures and keeping them on lung ventilators for weeks, means hospitals must make triage decisions. During a large swine flu outbreak the decisions will mean that people with other serious illnesses can die for want of hospital care.

So what are Americans facing, as the school year and flu season get underway? From one of the most quoted American authorities on the 2009 swine flu outbreak:
“The Northern Hemisphere medical care requirements for the next six months are a train wreck waiting to happen,” said Michael Osterholm, director of the University of Minnesota’s Center for Infectious Disease Research and Policy in Minneapolis. “In the fall, even if nothing else changes in terms of the virus’s severity and our preparedness, it’s going to be a real challenge.”(1)
From that perspective the CDC's updated guidelines to schools develop even greater importance than when they were published on August 7. Now to take up where I left off in the last post:

This post addresses the CDC's guidelines to U.S. schools on the use of non-medical or 'non-pharmacological' interventions (NPIs) to mitigate the effects of a swine flu outbreak in a school while keeping the school open.

My analysis is based on information in the CDC's online handbook, Technical Report for State and Local Public Health Officials and School Administrators on CDC Guidance for School (K-12) Responses to Influenza during the 2009-2010 School Year.

I note that the technical report links to a "technical handbook" that contains URL hyperlinks to various NPI topics addressed in the report, which resolves my earlier complaint about the report's dearth of hyperlinks.

My first post on the guidelines addressed screening for swine flu symptoms and the use of isolation rooms; the second one the length of time students/staff who'd recovered from flu should refrain from returning to school.

In both posts I observed that the CDC advice on every topic I'd covered was inadequate. It's as if, after announcing that they believed vaccination was the most effective means for combating influenza, they added NPIs merely to placate parents and school staff who demanded information on them.

The CDC advice to schools on hand washing and cleaning of surfaces continues the guidebook's curious hit-or-miss approach. Compare the CDC advice on hand washing with that given by the Canadian Center for Occupational Health and Safety.

If you tell me after reading the Canadian guidelines that many high school girls would refuse to forego artificial nails and nail polish -- this is the tiresome thing about pathogens: they don't give humans an A for a college try. Hand washing with regular soap doesn't 'kill' or neutralize pathogens; it rolls or washes them off the hands (something the CDC guidelines don't mention). So if nail polish is chipped the bugs can lodge in the cracks and thus avoid going over Niagara Falls. The same principle applies if the person doesn't scrub underneath long nails.

Anti-microbial soaps are better for schoolchildren provided the soaps are used properly -- washing at least 20 seconds (I think 30 seconds is better) and getting the soap under the nails.

The same with the anti-microbial gels. While some alcohol-based gels promise on their label to kill germs within 15 seconds of application I'd have to see the studies before I'd accept the claim. Recently I spent an evening in email conversation with a science researcher on the matter of exactly what strength ethyl alcohol should be used to kill pathogens and how long it takes for the alcohol to work. He told me that 70% solution is very effective and that it kills within 30 seconds.

It could be the popular 2 fluid oz. gel bottles can get away with a 62% solution because the alcohol is more concentrated in a small bottle. But until one of us can investigate further I'd stay on the safe side of waiting 30 seconds before assuming the stuff had worked.

A study has shown that people touch their face on average of 200 times a day; if you have the swine flu virus on your hands then rub your eyes or touch your mouth -- congratulations; you've given yourself the flu! From that perspective, be willing to spend an extra 10 or 15 seconds washing your hands properly when you're in a flu outbreak region.

I saw a television segment in which a school administrator in Georgia state proudly showed off large Purell anti-microbial gel dispensers that were placed in her school's halls. That's a great idea -- particularly because an easy way for students to become unpopular is if they hog a bathroom sink for a full 30 seconds of hand washing during the lunch break. But again, the little darlings need to be taught to get the gel under their nails and keep their nails clipped short.

Moving to the CDC guidelines on cleaning surfaces, this is one of the most troubling pieces of advice for schools wishing to deploy NPIs against swine flu:
The American Academy of Pediatrics provides guidance for school cleaning and sanitizing which is appropriate for influenza. Schools should regularly clean all areas and items that are more likely to have frequent hand contact (for example, keyboards or desks) and also clean these areas immediately when visibly soiled. Use the cleaning agents that are usually used in these areas.

Some states and localities have laws and regulations mandating specific cleaning products be used in schools. School officials should contact their state health department or department of environmental protection for additional guidance.

Schools should ensure that custodial staff and others (such as classroom teachers) who use cleaners or disinfectants read and understand all instruction labels and understand safe and appropriate use. Instructional materials and training should be provided in languages other than English as locally appropriate. CDC does not believe any additional disinfection of environmental surfaces beyond the recommended routine cleaning is required.

See the American Academy of Pediatrics’ Managing Infectious Diseases in Child Care and Schools: A Quick Reference Guide, 2nd Edition (2009) for guidance on cleaning and sanitizing in schools.

The EPA provides a list of EPA-registered products effective against flu.
That's it; that's all the CDC school guidelines have to say on the matter of cleaning, which means they omit discussion of how long pathogens can survive on surfaces. The link to the AAP quick reference guide is simply to a page with information on how to purchase the guide so I don't know whether the guide discusses the issue.

I assume that all U.S. schools have guidance from somewhere on the issue; however, it doesn't make sense for the CDC school guidelines to omit data on the crucial question of how long pathogens stay on surfaces -- particularly because there's a big discrepancy between data they cite elsewhere on their website and that from other sources. Here is what the CDC has to say on the topic at their H1N1 Flu and You Q&A page under the subheader Contamination and Cleaning:
How long can influenza virus remain viable on objects (such as books and doorknobs)?

Studies have shown that influenza virus can survive on environmental surfaces and can infect a person for 2 to 8 hours after being deposited on the surface.
Clearly other studies have a far different story to tell. During her radio interview with John Batchelor in July, Filligent CEO Melissa Mowbray-D'Arbela said that pathogens can live for "a day or a day and a half" on surfaces.

According to Mayo Clinic's James M. Steckelberg, M.D. (H/T Yahoo! Answers):
The length of time that cold or flu germs can survive outside the body on an environmental surface, such as a doorknob, varies greatly. But the suspected range is from a few seconds to 48 hours — depending on the specific virus and the type of surface.

Flu viruses tend to live longer on surfaces than cold viruses do. Also, it's generally believed that cold and flu viruses live longer on nonporous surfaces — such as plastic, metal or wood — than they do on porous surfaces — such as fabrics, skin or paper.

Although cold and flu viruses primarily spread from person-to-person contact, you can also become infected from contact with contaminated surfaces. The best way to avoid becoming infected with a cold or flu is to wash your hands frequently with soap and water or with an alcohol-based sanitizer.
Because Filligent scientists earn their living in a for-profit environment and thus, can't afford to get many facts wrong, I'd advise school administrators to assume the swine flu virus can live on surfaces for at least 36 hours.

If administrators in schools that saw swine flu outbreaks this Spring were following the 2-8 hour estimate put out by the CDC, it's possible they assumed they could get by with cleaning the most obvious 'touchable' surfaces, such as chairs and desks, and that the daily overnight closing of the school would take care of the rest of the viruses. If that's how they were thinking it's no wonder it was so hard to tamp down an outbreak in the schools.

Again, viruses don't grade humans for sincere efforts. I am reminded of a macabre but very telling joke that a guest on John Batchelor's show related during the SARS outbreak in China, which initially was traced to a military hospital:

"Looks as if the janitor missed cleaning a doorknob at the hospital."

Just because the school surface isn't touched often, if it's touched by any student and it has 'live' swine flu virus on it, bingo! it's being spread around the school faster than you can say hiss cat with every additional surface the student touches.

What's the solution, then? Given how hard it is to tamp down an airborne virus, isn't the CDC right to emphasize that a vaccine is the best defense against swine flu? If the vaccine is available and it's well-matched to the virus, yes. However, as I mentioned earlier, there's been a glitch with the swine flu vaccine delivery for the USA.

For months CDC assured the public and school administrators that the first delivery of swine flu vaccine, scheduled for mid-October, would be 120 million doses. On August 17 they announced that the October delivery would only be 45 million doses.

Figure half that amount if the human vaccine trials, which are still underway, determine it'll take two doses of vaccine to provide adequate protection. Right now the public health community is betting that two doses will be needed.

HHS has leaped to assure, according to this AP report:
It's not a shortage but a delay, Health and Human Services spokesman Bill Hall said. More will arrive rapidly after that, with about 20 million more doses being shipped weekly until the government reaches the full 195 million doses ordered, he said.

But the October shortfall, blamed on manufacturing issues, will extend by a month efforts to get people at highest risk vaccinated against the new flu strain. First in line are supposed to be pregnant women, children and health care workers, followed by younger adults with flu-risky conditions such as asthma.

Expect vaccination campaigns to start around Oct. 15 anyway, Hall said. They just will have to be smaller in scale than originally planned, as the supply trickles in more slowly.

"Why would we wait? As vaccine comes in, we'll ship it out to the states. We're not going to sit on it," Hall said.[...]
Yes, well, that's not the biggest issue. There are between 53 and 55 million children and 7 million staff at U.S. schools. The CDC - HHS updated recommendation on August 7 that schools open on time in September and stay open, even during a swine flu outbreak, was based on their rosy prediction that large-scale vaccinations of schoolchildren would begin in mid-October.

I bought into the prediction because I assumed the CDC wouldn't be so stupid as to make the recommendation without being certain that the first shipment of vaccine would be 120 million doses. That's why I suggested in an earlier post that U.S. schools in regions with swine flu outbreaks delay opening until vaccine had been administered in mid-October.

Keep in mind that it takes three to six weeks for a vaccine to reach full effectiveness, with three weeks the time used in the NIH-funded human vaccine trials to discover whether one or two doses of vaccine are needed.

The delay in the vaccine program changes everything. So I suggest that parents, school administrators, and public health officials read Jason Gale's report with great care, then revisit their thinking about the best course for handling a swine flu outbreak in schools. If they are determined to open the schools on time and keep them open during swine flu outbreaks, that leaves NPIs to bridge the gap until the vaccine program is well underway.

The NPI route is very hard, very labor intensive. And as you can see from all the above, a highly infectious virus allows humans little room for error when they're closely grouped. This doesn't mean NPIs shouldn't be used in abundance in the schools; on the contrary. Secondary infections can be a bigger killer than a virus during a pandemic.

The NPIs, if done right, will greatly reduce germs of all kinds, including bacteria that exacerbate viral outbreaks in schools. However, the emphasis is on "done right." So another thing the CDC can do is clean up the errors, omissions, and contradictions I've noted in this three-part series on their NPI guidelines.

1) Bloomberg: Swine Flu Pandemic Paradox Kills Few, Overwhelms ICUs: Jason Gale; August 21, 2009


CGardner said...

Pundita, a question. . .

Have you heard anything about the govt. deciding to use adjuvants, given that the vaccine supply has been decreased for the Oct. deadline?

Pundita said...

CG -- No, I haven't heard anything. Supplies are so tight globally that even if the US wanted to use adjuvants it seems a little late in the day for that decision.

(I haven't heard of any shooting yet over who gets that vaccine but give it time LOL. There's a lot of controversy about the wealthy countries snapping up so many of the vaccine supplies.)

However, WHO is calling for the use of adjuvant in swine flu vaccine to increase the global supply of the vaccine.

Problem is, there is no data on how adjuvants affect pregnant women and children, so I don't think that idea will get anywhere in the USA -- at least, not this year.

Two of the five US suppliers, Novartis AG and Sanofi Pasteur, make a vaccine with adjuvant for Europe and I assume other countries, but not for the USA.

MedImmune has come up with an idea of using nose drops to deliver the vaccine. I think they use a live virus, though, so unless things get really desperate (or unless a lot of Americans don't know that reportedly a live vaccine is somewhat riskier than the killed-virus vaccine) I can't see a lot of takers.

But I'm not well informed on the live vs killed vaccine debate. I note the following quote mentions that their nasal spray is for "healthy" people and those over 2 years and under 50. That may be the problem with live virus vaccines -- maybe people with underlying health conditions or weaker immune systems don't tolerate them as while, although I'm just guessing.

According to the WSJ:

"MedImmune, which makes a nasal-spray version of seasonal flu vaccine for healthy people aged 2 to 49 years old, has made a greater volume of vaccine for H1N1 swine flu than what it anticipates making for seasonal flu, said Karen Lancaster, a company spokeswoman. It's producing 12 million doses of H1N1 vaccine compared with 10 million doses of seasonal flu vaccine.

Though it faces limitations on the number of sprayers available, MedImmune has been able to get good yield for its H1N1 vaccine, Lancaster said.

What's more, the company may be able to deliver more swine-flu doses relatively quickly if the U.S. Food and Drug Administration approves a proposed new application that would deliver vaccine through nose drops, she said.

"We hope it might be a good, viable option for having more vaccine available to more people sooner," Lancaster said.

CGardner said...

Sebelius has already purchased over $400 million in adjuvants for the federal drug "stockpile."

Pundita said...

Oh right; I forgot about that panic move.