influenza monitor

Acording to the latest CDC estimates, there have been just over 12,000 deaths from pandemic 2009 H1N1. This stands in contrast to the 36,000 deaths from a typical flu season, a number widely advertised by HHS. This, along with similar fatality rates were observed worldwide, has led some to describe the H1N1 pandemic as “moderate” or even “mild.” But was that really the case ?

Mike Osterholm, of CIDRAP at the University of Minnesota, makes the point that such descriptions hinder us from remembering the true impacts from the pandemic and learning the right lessons.

Though H1N1 was of low pathogenicity overall, when it struck, it hit hard disproportionately against the young, who were immunologically naive, and against pregnant women, who have lower overall immunity. The average age of those who died was 34.7 years. Hence measures that factor in age, such as Years of Life Lost, show a much higher societal impact of H1N1.

Severe H1N1 cases involved deep lung infections and with tissue necrosis, soon followed by respiratory failure. This had of the effect of straining hospital intensive care units (ICU’s) to their operational limits, across several countries. In Australia, ICU’s were reportedly “at the point of collapse” in 2009. Hospitals in the U.S. adjusted visitation policies to limit the potential spread of infection.

Contrary to expectations, the second H1N1 wave reemerged in late summer continuing into the the school year, leading to record numbers of school closures, something that is not typical of normal flu epidemics. Though exactly hard to determine, school closures probably had some spillover effect on lost economic output, and productivity owing to worker absenteeism

In late October and mid November as the second H1N1 pandemic wave intensified, and as H1N1 deaths surged, there were insufficient vaccine supplies on hand to meet peak demand. A switch to cell-based methods of vaccine production, along with improved distribution methods, could have saved lives.

ABC: Swine flu put hospitals ‘on edge’ last year
Medscape Medical News: Lessons Learned From the H1N1 Pandemic Are Meager

Tagged: Care and Treatment, flu, h1n1, influenza, International News, pandemic flu, swine flu, US News, Vaccine Updates

When writing about influenza, it can be difficult to report on cutting-edge research. One has to carefully apply terms like “breakthrough.” One also has to avoid terms like “miracle cure.”

A universal flu vaccine, that can provide extended protection across a variety of recombitant influenza viruses represents the pinnacle for microbiological research in this area. While this goal remains years away, there are some promising lines of approach.

Current influenza vaccines essentially are aimed at narrow range of viruses that are currently in circulation. “Frequent minor changes in flu viruses involve two surface proteins, hemagglutinin and neuraminidase, represented by the H and N in virus names.”

The hemagglutanin (HA) surface protein is a “mushroom-shaped structure helps the virus attach to the cells it infects” The problem arises when the HA attack surface changes due to antigenic drift, requiring annual updates to the seasonal flu vaccine. Hence, some modern lines of research toward a universal vaccine try to take aim at those sections of HA portion of the virus that are relatively static over time and are consistent over several strains.

Researchers at Mount Sinai School of Medicine in New York developed
a proof-of-concept designed to help the immune system develop antibodies that target a headless hemagglutanin (HA) molecule. Thus far trials have proven successful in mice.

Other lines of research over recent years have taken aim at “M2”, a relatively stable protein found in Influenza A viruses.

Other molecular research has not centered on influenza virus itself but rather on finding human host factors and classes of natural flu fighting proteins that inhibit virus replication.

CIDRAP: Acambis launches human trial of ‘universal’ flu vaccine
CIDRAP: Firm says ‘universal’ flu vaccine passed early test
mBio: Influenza Virus Vaccine Based on the Conserved Hemagglutinin Stalk Domain
Reuters: Researchers take step to ‘universal’ flu vaccine

Tagged: Care and Treatment, flu, h1n1, influenza, International News, pandemic flu, swine flu, US News, Vaccine Updates

The most significant failure in the global public health response to pandemic H1N1 was the lack of sufficient vaccine supplies in time for the second wave of H1N1.

According to reporting from the World Health Organization (WHO) H1N1 Influenza Vaccine Task Force, global influenza vaccine production continues to fall well short of WHO’s desired production targets owing to a variety of factors.

In 2006, WHO set a goal of having vaccine supplies sufficient for two billion persons within six months of the provision of a pandemic strain to industry. H1N1 vaccine production fell well short of this goal, amounting to only 534 million doses within the six-month milestone, which was reached in December 2009.

Reasons for this trace to lower-than-expected production yields associated with egg-based production methods (H1N1 vaccine yields were two-thirds lower than their seasonal vaccine counterparts). WHO researchers also noted reluctance among some regulatory bodies to approve vaccines with adjuvants (immune system enancing additives) to stretch vaccine doses. Declining H1N1 vaccine demand and requirements for seasonal vaccine production were additional factors.

Flu vaccine production still remains mostly concentrated within a few developed countries and “among seven large manufacturers that are located in the USA, Canada, Australia, western Europe, Russia, China, and Japan.” However, overall vaccine production capacity is expanding. In 2006, vaccine production was centered in nine industrialized countries. At present, influenza vaccine production “is currently available or is being established in 25 countries.”

Within the USA, the President’s Council of Advisors on Science and Technology (PCAST) recently presented a series of recommendations to improve pandemic vaccine production. In the short term, key recommendations included shifting vaccine production from egg-based methods to cell-cultures, improved seed strains and testing as well as larger and more modernized facilities.

Among the longer-term recommendations were support for adjuvenated vaccines, capacity to test and develop vaccines against at least pandemic virus threats, research toward a universal vaccine, and improved guidance from the U.S. Food and Drug and Administration to streamline approvals of new vaccines.

CIDRAP: President’s advisory group looks to speed up flu vaccine
CIDRAP: WHO: Pandemic showed limits of vaccine production capacity

Tagged: Care and Treatment, flu, h1n1, influenza, International News, pandemic flu, swine flu, US News, Vaccine Updates