Thursday, October 7, 2010

Expert pair airs lessons learned from global flu response

Lisa Schnirring Staff Writer

Oct 6, 2010 (CIDRAP News) – Two internationally known health officials yesterday gave their assessment of the global response to the 2009 H1N1 pandemic, saying good decisions were made based on what was known early in the outbreak but adding that the experience yielded several important lessons, such as the need for more flexible pandemic plans and the need to communicate more clearly about risks.

The experts are Dr Gabriel Leung, of Hong Kong's Food and Health Bureau, and Dr Angus Nicoll, of the European Center for Disease Prevention and Control in Stockholm. An essay they wrote on their pandemic observations appeared yesterday in the Public Library of Science (PLoS) Medicine. Their review covers the first 12 months of the pandemic response.

Their reflections on the world's pandemic response comes in the midst of an independent review of the World Health Organization's (WHO's) response and how the International Health Regulations (IHRs) functioned in their first major test during a public health crisis.

Though the 2009 H1N1 virus seemed to cause mild-to-moderate infections in most people, experts are still sorting out the mortality impact, Leung and Nicoll wrote. Young people were among the hardest-hit groups, and their deaths amount to more years of life lost than the deaths involving older people and those with chronic medical conditions.

Some countries turned quickly to containment strategies when the new virus emerged, using nonpharmaceutical interventions such as isolation and quarantine of people with suspected and confirmed disease, which in some ways was understandable for countries that had already grappled with the H5N1 avian influenza virus and the 2003 SARS epidemic, the authors wrote.

Though some of the measures may have delayed community transmission, it's unclear if the benefits were worth the costs, according to the authors.

Until the pandemic virus emerged, hardly any countries except Japan had used antiviral medications widely. Some struggled with whether to use the drugs for the treatment of sick patients or to prescribe them for prophylaxis. A few countries, such as England, developed innovative distribution methods.

Early evidence suggests that neuraminidase inhibitors reduced severe disease without causing adverse events, Leung and Nicoll wrote. However, they added that delayed antiviral treatment was linked to more severe complications worldwide, which points to gaps in indentifying and treating patients early.

The authors gave mixed reviews to the pandemic vaccine. Though they said it was a scientific success, it arrived too late with not enough supply to blunt the Northern Hemisphere's second pandemic wave. They noted that public health officials struggled with a difficult message when urging people to get the vaccine—that although the virus usually caused mild disease, it could sometimes be lethal, even in young and previously healthy people.

Though some critics have questioned their countries' expenditures for what may have later appeared to be excessive amounts of vaccine, the authors noted that when health officials placed their orders they didn't expect the later finding that a single dose rather than multiple doses was immunogenic in all but the youngest children.

"Hindsight always gives perfect vision and using post-hoc information to evaluate prior decisions at best confuses and often produces unfair conclusions," Leung and Nicoll wrote.

In addressing critics' charges that vaccine makers may have improperly influenced the expert advice WHO relied on in determining their recommendations and response actions, Leung and Nicoll emphasized that receiving advice is different than making decisions. Advisors' declarations of interest should be fully transparent and comprehensive and follow strict rules that can hold up to intense scrutiny, they said, and "The decision makers should also be prepared to justify their actions."

They predicted that communication about risk will remain a challenge in the months ahead because the 2009 H1N1 virus could undergo antigenic drift, given the greater number of people who are now immune through infection or vaccination.

As the lessons emerge about the pandemic response, countries will likely be retooling their pandemic plans, the authors wrote, urging the WHO to take a leadership role to coordinate the efforts. "A strong argument exists for making future plans more flexible and having extra descriptions including the many aspects of severity when a pandemic is emerging that then determine the consequential public health actions," they stated.

Their other recommendations include:

Establishing a clinical research infrastructure to help speed the collection and sharing of clinical data during the next flu pandemic or other disease outbreak
Improving surveillance systems to help gauge the true burden of flu
Developing new tools for treating severe flu infections.
Easing developing countries' access to antiviral medications and vaccines still represents a big gap, the authors wrote. "It is an indefensible fact that these vaccines started to flow to the poorer countries well after they began going to the countries with advance purchase agreements."

However, they noted that the long-term solution isn't simple and includes improving surveillance, monitoring disease burden, expanding flu prevention and control efforts, and establishing seasonal flu vaccine production and use in all parts of the world.

Study explores Southern Hemisphere pandemic patterns

Lisa Schnirring Staff Writer

Oct 5, 2010 (CIDRAP News) – A review of how the first wave of the 2009 H1N1 pandemic affected Southern Hemisphere countries found many similarities with Northern Hemisphere countries, though many patients had no underlying risk factors for flu complications and pregnant women didn't seem to have severe outcomes.

The authors from Greece and from Tufts University School of Medicine in Boston based their findings on 15 studies in the medical literature that described the epidemiologic findings in the Southern Hemisphere. They published their findings today in an early online posting by Epidemiology and Infection.

Seven of the studies detailed the experience of South American countries, six covered Australia and New Zealand, and two focused on Africa.

The Southern Hemisphere experienced its first pandemic wave during the region's 2009 winter influenza season (northern summer). Some countries, such as New Zealand and Australia, recently saw or are in the midst of a second pandemic wave. Australia's health ministry said in its most recent report that flu activity is increasing, with nearly 70% of cases caused by the 2009 H1N1 virus. The rise in cases there is unusual, coming at the end of the flu season.

All but one of the studies included in the literature review contained data on the characteristics of patients with lab-confirmed 2009 H1N1 infections.

In patients whose respiratory samples were evaluated with reverse -transcript polymerase chain reaction (RT-PCR) testing, the rate of positives ranged from 31.5% to 54% in four studies from Brazil, Argentina, and Australia, though a reference laboratory in Bolivia reported a lower rate of 12.7%. The positive rate was even lower, about 8.3%, in two Brazilian studies, and a general hospital in Argentina has a 3.3% positive rate.

Hospitalization rates in confirmed cases were about 45% in Brazil and Argentina and varied from about 17% to 31% in Australia and New Zealand.

Among five studies that included data on fatality levels, rates ranged from 0.5% to 0.9%.

The majority of lab-confirmed 2009 H1N1 cases were in young and middle-aged adults, with the second highest levels of infections in older children and adolescents. Though fewer seniors were affected, the ones who were sickened were more likely to be hospitalized, to be admitted to an intensive care unit, or to die. .

Nearly 67% of patients with severe infections did not have underlying medical conditions. Common conditions in patients that did have risk factors for flu complications included, for example, chronic respiratory disease such as asthma, cardiovascular disease, renal insufficiency, and diabetes.

Studies that included information on pregnant women reported that this group accounted for between 5.4% and 8.1% of severe infections. However, they didn't find that pregnant women were substantially more likely to be hospitalized or admitted to the ICU. "In other words, pregnancy might be mostly a risk factor for acquisition of infection with pandemic A (H1N1) 2009 influenza virus, rather than for an adverse outcome, " the researchers wrote.

They noted that pregnant women were more likely to be in the age-group most affected by the virus and may often have close contact with young children, who could expose them to the virus.

The researchers found that a substantial number of obese people were sickened during the pandemic wave, a pattern that also emerged in the United States and other Northern Hemisphere countries. However, the group emphasized that their findings concerning pregnant and obese patients were just observations.

They also pointed out that most cases of pandemic flu were mild and uncomplicated and went undiagnosed. Because their review focused on lab-confirmed cases, they said, it doesn't capture the true impact and characteristics of the 2009 flu pandemic in the Southern Hemisphere.

WHO pandemic review group concludes third session

Lisa Schnirring Staff Writer

Sep 29, 2010 (CIDRAP News) – The external committee tasked with reviewing the World Health Organization's (WHO's) response to the H1N1 pandemic wrapped up its third round of live meetings in Geneva today, hearing from an array of country and organization health representatives, as well as WHO Director-General Margaret Chan, who strongly defended the organization's response.

Chan, who spoke to the group yesterday during a public plenary session on the second day of its meeting, also said the WHO learned some important lessons that will position it to, for example, ease the flow of pandemic vaccine to developing countries. Her address to the group appeared yesterday on the WHO's Web site. The pandemic review committee is simultaneously reviewing how the International Health Regulations (IHRs) functioned during their first use in an international health emergency.

Dr Harvey Fineberg, the group's chairman, briefed reporters today at the conclusion of the group's 3-day meeting. He said the committee is still in an information-gathering mode and that the agenda consisted of public plenary sessions and deliberation meetings during which members met by themselves. He is president of the Institute of Medicine of the US National Academy of Sciences.

The review committee's last meeting in Geneva was in early July, and Fineberg told reporters the committee will meet again in November for deliberation sessions. He projected that the group would have a draft of a report for its own members to review by early January in time for its final plenary meeting. The members will submit a final report that includes a response from Chan in advance of the World Health Assembly next May.

Fineberg said the group heard testimony from a wide range of health and industry experts and confirmed, based on a journalist's question, that Michael T. Osterholm, PhD, MPH, addressed the group during the plenary sessions. Osterholm is director of the University of Minnesota's Center for Infectious Disease Research and Policy, publisher of CIDRAP News.

One of the largest blocks of testimony came from key people who led the WHO's response and were involved in administering the IHRs, including Chan, Fineberg said. At the committee's last meeting in July they heard from some of sharpest critics of the WHO's response, including a Council of Europe representative and the editor of the British Medical Journal.

"One of the things that was not surprising, but very revealing, was that the principals at the WHO secretariat were very eager to tell their story," he said. "They are as eager to tell their story as the critics are to tell theirs."

Chan spoke candidly about the challenges and successes she observed during the WHO's pandemic response and said the group welcomes the review and is mindful of the praise and criticisms it has received. She said the WHO is grateful for the moderate impact the pandemic had, and she said in retrospect some response measure may look excessive.

"Had the virus turned more lethal, we would be under scrutiny for having failed to protect large numbers of people," Chan said. "Vaccine supplies would have been too little, too late, with large parts of the developing world left almost entirely unprotected."

She said experts assumed that H5N1, with its more lethal severity, would cause the next pandemic, which guided preparations for a more severe pandemic than what emerged with the 2009 H1N1 virus. The phased pandemic alert approach was developed as cues to help countries increase their preparedness levels without causing public alarm. "In reality, it had the opposite effect. It dramatized the steps leading to the declaration of the pandemic and increased the build up of anxiety," Chan said.

Chan rejected charges that the WHO exaggerated the pandemic threat and said when she announced the move to alert phase 6 she reminded the world that the number of deaths were small, that she didn't expect to see them increase suddenly, and that most patients were recovering without medical care.

During a time when health officials had to make decisions in an environment of scientific uncertainty, most health officials erred on the side of caution, she said. "In this regard, the phased approach to the declaration of a pandemic was rigid and confining. In communicating the level of alarm, authorities need to be able to move down as well as up," Chan said, adding that limited vaccine capacity and long production times also hampered the flexibility of countries' pandemic responses.

She strongly rejected charges that commercial interests tainted the WHO's pandemic alert level decisions. "I can assure you: never for one moment did I see a single shred of evidence that pharmaceutical interests, as opposed to public health concerns, influenced any decisions or advice provided to WHO by its scientific advisors," Chan said in her statement.

On a positive note, Chan said some elements of the world's pandemic response worked well, including the IHRs, which she said provided a useful set of checks and balances, and the early distribution of oseltamivir stockpiles to developing countries.

"In my view, the Emergency Committee, with both experts and affected states represented, functioned well as a balanced and inclusive advisory body," she said. The emergency committee met at least nine times to advise Chan during pandemic phase and response discussions, and some critics charged that the process lacked transparency, because member names were confidential. The WHO has said the names were kept secret during the pandemic to protect members from undue influence. It revealed the member names on Aug 10 when the WHO declared that the pandemic was over.

In response to journalists' questions, Fineberg said several times that the role of the committee isn't to assign blame, but to identify ways that the WHO can improve its pandemic response.

He said the review committee is hearing a lot about the challenge of decision making under conditions of great uncertainty and that some response measures, such as the vaccine donation process, are very complex.

"Everyone came at this from their own perspective, but few had a vision of the whole. Each told an important side of the story," Fineberg said. "Our job is making a coherent whole out of these perspectives."