Give Public Health 'Just Credit' for Minimizing Impact of H1N1

The 2009 H1N1 influenza outbreak was officially elevated to pandemic status on June 11, 2009.

Earlier this month, on August 10, 2010, the World Health Organization (WHO) declared it officially over.

What does this mean?

To many people, both the start and end dates seem somewhat arbitrary.  Indeed, there are undoubtedly some who think the outbreak never should have been declared a pandemic at all.  Certainly, there are many local communities seemingly untouched by 2009 H1N1.

As with much in public health, to understand these determinations, it is useful to consider the Big Picture.

Pandemics have three basic defining characteristics:

1. They must involve the emergence of a novel, infectious microbe to which people have had no previous exposure and therefore little to no natural immunity.  In this case, “novel” means that there is not a documented history of the disease having infected people or the disease hasn't infected people in such a long time that it unlikely anyone will have immunity.
   
2. They must be pathogenic; that is, they must have potential to make people sick, and often significantly so.
   
3. Last, but not least, pandemics must involve sustained human-to-human transmission over a large geographic area. (The official WHO criteria for a Phase 6 pandemic—the highest level—requires sustained community level outbreaks in at least two countries in one WHO region, plus at least one other country in another region.) 

The 2009 H1N1 virus handily meets all three criteria. It was clearly a unique influenza subtype with its association with swine-origin viruses. It had significant morbidity and mortality:  almost 1.5 million cases worldwide, including roughly 45,000 laboratory-confirmed US cases; and just over 25,000 deaths worldwide, including 10,837 US deaths. And by the end of the pandemic this month, there had been sustained human-to-human transmission in dozens of countries all over the world. In fact, during the pandemic, 2009 H1N1 crowded out other influenza viruses to become the dominant strain, infecting 20-40% of populations in some areas.

In this post-pandemic period, a significant chunk of the world population has now been exposed to the virus—either directly or through vaccination—and thus has some immunity. Rates of sustained transmission are generally leveling off or falling off. Many countries are reporting a mix of circulating flu viruses. . . . . In other words, 2009 H1N1 is behaving more and more like a seasonal flu virus. In fact, now that it is no longer novel—meaning that it now has a well documented history of having infected people—it should never again qualify as a pandemic virus. But that doesn’t mean it has gone away.

Given the justified concern about a pandemic involving avian influenza, with its 50-60% mortality rate, 2009 H1N1 may, in retrospect, seem mild to some. This is good news, partly a result of effective public health intervention and, as stated by the WHO director-general, partly “pure good luck.”

Pete Shult, PhD, head of the Communicable Disease Division at the Wisconsin State Laboratory of Hygiene and an influenza expert, said that back in April 2009, health authorities had “no clue what was going to happen here.”

He said, “Did the government overreact? No. Absolutely not. I think we should take our just credit. We were able to diagnose [2009 H1N1] quickly. We were able to get vaccine out there. We were able to help the health community respond effectively. I’m not sure in the absence of those efforts this wouldn’t have been a worse pandemic. . . .You always have to plan for the worst case.”

And now that it’s over, what can we expect from 2009 H1N1 in the future?

Said Shult, “We’re in uncharted territory. We’ll see what happens.”

Cross-Border Influenza Preparedness

by Chris Mangal, director of emergency preparedness and response

On August 31-September 1, 2009, in Winnipeg, Canada, APHL's leadership and infectious disease, preparedness and global health staff met with key officials from the Canadian Public Health Laboratory Network (CPHLN) to discuss collaborative activities, such as lessons learned from the recent H1N1 outbreak and planning for a tri-national cross-border preparedness summit. In addition, APHL staff toured the Emergency Operations Center of the National Microbiology Laboratory and learned about their Incident Command Structure used to respond to infectious disease outbreaks.

Following the meeting with CPHLN, APHL staff (Scott Becker, Mary Shaffran, Chris Mangal and Natalia Machuca) attended the first conference of its kind in Canada, “Severe H1N1 Disease: Preventing Cases, Reducing Mortality,” organized by the Public Health Agency of Canada (PHAC).

Dr. Graham Tipples from PHAC served as the Master of Ceremonies, welcoming key public health officials, including the Honorable Leona Aglukkaq, Canada's Minister of Health. The minister noted that this conference was the first of its kind to bring together clinicians, laboratorians and key public policy officials. She mentioned that the conference will help Canada to better prepare for and respond to the upcoming influenza season. The minister also mentioned that continued monitoring and surveillance for H1N1 along with consistent collaborations, information exchange and strong partnerships will be vital to keep the population healthy and prevent and manage the spread of H1N1.

The Manitoba Minister of Health, the Honorable Theresa Oswald, welcomed participants to Winnipeg, but stated, “I really wish you weren't here." This statement is a reflection of the growing concerns about the upcoming flu season and the potential for H1N1 to be more widespread, affecting the general population and overwhelming the healthcare systems globally.

Dr. David Butler-Jones, chief public health officer, PHAC, addressed the dilemma of managing and measuring H1N1. He noted that "you can't manage what you don't measure," but also mentioned that the fluidity of H1N1 cases makes it difficult to measure and as such public health officials must be creative in responding to this pandemic.

Dr. Frank Plummer, chief science advisor, PHAC, further explained the objectives of the conference, noting that he hopes participants leave with a better understanding of epidemiology and severity of the disease, clinical care and management issues, intensive care unit challenges and strategies to manage H1N1 cases. He also encouraged further connections among hospitals, infection control and public health.

Dr. Charles Penn, Global Influenza Programme, World Health Organization (WHO) addressed the current status of the pandemic and WHO efforts to facilitate communications globally, mobilize resources and provide access to vaccines and antivirals. Several additional sessions, including in-depth discussions on modeling scenarios, provided participants with more information on Canada's efforts to prepare for and respond to H1N1.

APHL will continue our collaboration with Canada and look to build stronger linkages with Mexico to ensure that there are robust laboratory systems in place to detect and respond to infectious disease outbreaks globally.

Flu Appropriation Update

Great news! The Senate Appropriations Committee has recommended approving $900 million in emergency flu funding. Even more importantly, the Committee has recognized the importance of hiring PHL staff. Taken from the report itself:

“The Committee notes that the economic downturn has forced States and local governments to lay off public health laboratories and other public health professionals.”

The House Appropriations Committee has already taken similar action by adding $350 million for State and local government capacity building in its version of the emergency flu funding bill. Their report also references the impact of the lay offs.

You can see the full text of the Senate report here and the full text of the House report here.

Lab Capacity Model

The CDC-APHL State Lab Capacity Modeling Analysis model, developed to generate data on laboratory processes over the course of a pandemic, allows for states to refine their pandemic plans based on their individual resources and needs. Information generated from running the model identifies resource gaps and bottlenecks that may occur during a pandemic surge. Further, it allows for optimization of strategies for increasing respective capacities. Data entered into the model can be easily reconfigured, to determine how adding or removing resources affects throughput.

The recent and ongoing 2009 Novel Influenza A H1N1 (swine-like) outbreak offers a real-life scenario with which to assess the predictive value of these models. Compilation of data and of measurement evaluations continues, particularly as this event constantly evolves. Preliminary evidence proves, however, that the bottlenecks predicted by the model have proven to be true. Specifically, North Carolina, with seven confirmed cases and thousands of samples tested, reports that the model proved correct when predicting that the accessioning, extracting, and reporting stages would result in bottlenecks.

The feedback from the state—that the model was correct—is indicative of the fact that such practices are useful and carry value. We anticipate receiving feedback from other states, and are optimistic that this tool can be utilized in the future for more effective planning and capacity assessment purposes.

Flu Appropriation

The House of Representatives pushed through a $350 million appropriation for desperately-needed federal funding for state and local government public health organizations.

This funding will help combat many of the cuts government public health labs have had to make during the current recession. A recent APHL survey found that in 2008 alone, labs laid off or left unfilled almost 430 full-time positions, and expected to see another 230 positions empty in 2009. This proposed budget appropriation will go a long way to restoring vital lab capacity—it is critically important that labs retain and reclaim their highly trained workforce.

Despite severe workforce gaps, in the past few weeks, government labs still managed to test thousands of samples and keep the H1N1 outbreak just that—an outbreak—and not a pandemic. However, we’re not out of the woods yet. While things have certainly quieted down in the media, the H1N1 outbreak underscores the need to strengthen public health surveillance and detection of any novel flu strains that may appear.

Yet, that proposed $350 million in funding may still die—unless the Senate acts quickly and decisively. As it stands now, the full Senate will not begin actively debating the proposed appropriation until next week. If the Senate does not match the House with this funding, public health infrastructure will continue to erode in the wake of continued budget cuts.