Influenza Virus Mashup

Via YLE: New Swine Flu Vaccination Drive Planned. Excerpt:

Fewer Finns than expected have been vaccinated against the H1N1 influenza. With only about half of the population having had the swine flu jab, there are at least 1.5 million unused doses left. 

Health clinic staff say that the number of people seeking shots dropped off sharply around last March. 

The remaining doses are still usable until the end of next May. Thus Finland is not in the same situation as the Netherlands, which is disposing of some 17 million unused doses that will soon pass their expiration dates. 

Many other countries seem to have wasted large sums in acquiring the swine flu shots. The Council of Europe is looking into whether the World Health Organisation was too hasty in declaring swine flu as a pandemic. 

The value of the shots remaining on the shelf in Finland is about 10.5 million euros. However the state’s acquisition of the vaccine was not overblown, says Senior Researcher Rose-Marie �lander of the National Institute for Health and Welfare (THL). 

Public health authorities believe that at least some of the remaining doses will be used this autumn. They are planning a new campaign to encourage the young in particular to get the jab.

Via NZHerald.co.nz: School hit hard by swine flu.

An outbreak of swine flu at Seddon School in Marlborough has affected nearly half the school roll. 

At its peak 46 children out of a roll of 107 were ill prompting the Public Health Service to investigate. 

Nelson Marlborough Medical Officer of Health, Dr Ed Kiddle says swab tests were taken from sick children during the week and the results confirmed cases of the H1N1 virus, however the outbreak is now starting to wane.

(Sat, 31 Jul 2010 12:38:00 +0000)

# 4773

With the recent attention being paid to Dengue and other vector borne diseases here in Florida and around the United States, public health departments are urging people to become more diligent about removing breeding places for mosquitoes around their homes.

But it isn’t just outside the home where people need to check . . .  some mosquito species are perfectly capable of setting up light housekeeping inside the home as well.

While the Aedes aegypti is most commonly associated with spreading disease, the Aedes Albopictus or `Asian tiger’ mosquito is quite capable of doing so as well.

A couple of resources and some discussion.  

First, a link to the South Florida Sun Sentinel which has a story about one type of Dengue mosquito found breeding inside south Florida residences.

Mosquitoes carrying dengue fever can live indoors

Aedes has been found in Waterpiks, fridge trays, toilets

By Bob LaMendola, Sun Sentinel

7:43 PM EDT, July 30, 2010

Next, a timely study which appears in PLoS One  titled:

Indoor-Breeding of Aedes albopictus in Northern Peninsular Malaysia and Its Potential Epidemiological Implications

Hamady Dieng^1*, Rahman G. M. Saifur¹, Ahmad Abu Hassan¹, M. R. Che Salmah¹, Michael Boots², Tomomitsu Satho³, Zairi Jaal¹, Sazaly AbuBakar⁴

Background

The mosquito Ae. albopictus is usually adapted to the peri-domestic environment and typically breeds outdoors. However, we observed its larvae in most containers within homes in northern peninsular Malaysia. To anticipate the epidemiological implications of this indoor-breeding, we assessed some fitness traits affecting vectorial capacity during colonization process. Specifically, we examined whether Ae. albopictus exhibits increased survival, gonotrophic activity and fecundity due to the potential increase in blood feeding opportunities.

Methodology/Principal Findings

In a series of experiments involving outdoors and indoors breeding populations, we found that Ae. albopictus lives longer in the indoor environment. We also observed increased nighttime biting activity and lifetime fecundity in indoor/domestic adapted females, although they were similar to recently colonized females in body size.

Conclusion/Significance

Taken together these data suggest that accommodation of Ae. albopictus to indoor/domestic environment may increase its lifespan, blood feeding success, nuisance and thus vectorial capacity (both in terms of increased vector-host contacts and vector population density). These changes in the breeding behavior of Ae. albopictus, a potential vector of several human pathogens including dengue viruses, require special attention.

Although this particular study is set in Malaysia, the Aedes albopictus mosquito has made extensive inroads in the rest of the world over the past 40 years, and is considered one of the top 100 worst invasive species according to the Global Invasive Species Database.

Dark Blue indicates the A. Albopictus native range, while green indicates new introductions in last 40 years.

While mosquitoes are pretty much ubiquitous here in Florida, as well as in and many other areas, one shouldn’t panic over being bitten.

 

The vast majority of mosquitoes here in the US are not carrying infectious diseases.

 

The odds of contracting West Nile Virus, Dengue, EEE, or any of the mosquito borne encephalitis viruses are actually pretty small.

In order to vector a disease, they first must bite a host(bird, animal, or human) that is viremic – infected and with sufficient viral material in their bloodstream.

Still, it makes sense to take precautions. 

Like wearing DEET when you are outdoors, wearing long sleeves and pants, and removing breeding places inside and outside of your home.

Any container of water . . .  even as small as a bottle cap . . . can breed mosquitoes.  Containers with houseplants appear to be particularly good homes for these pests.

For more details visit the Florida DOH Mosquito-borne Disease Prevention webpage.

(Sat, 31 Jul 2010 10:53:00 +0000)

# 4772

With the US flu vaccination season nearly upon us, the FDA announced yesterday the approval of the following vaccines for use in the United States during the 2010-11 flu season:

Afluria, CSL Limited

Agriflu, Novartis Vaccines and Diagnostics

Fluarix, GlaxoSmithKline Biologicals

FluLaval, ID Biomedical Corporation

FluMist, MedImmune Vaccines Inc.

Fluvirin, Novartis Vaccines and Diagnostics Limited

Fluzone and Fluzone High-Dose, Sanofi Pasteur Inc.

These vaccines all combine the 2009 pandemic strain with two other flu strains expected this fall.

Specifically:

• A/California/7/09 (H1N1)-like virus (pandemic (H1N1) 2009 influenza virus)
• A/Perth /16/2009 (H3N2)-like virus
• B/Brisbane/60/2008-like virus

Sanofi Pasteur’s Fluzone High-Dose was approved earlier in the year for seniors over the age of 65 who normally don’t get as much protection from flu shots as do younger recipients.

This new high-dose flu vaccine contains 4 times the normal amount of antigen; 60 µg of each of the three recommended strains, instead of the normal  15 µg.

Studies have indicated a more robust immune response occurs in seniors receiving this higher dose shot (see Flu Shots And The Elderly and  MMWR On High Dose Flu Vaccine For Seniors).

In March, ACIP announced that this new formulation would be available along with standard flu shots this fall, but did not announce a preference for one shot over the other. Those interested should discuss this option with their family physician.

CSL Limited’s offering, Afluria, is also on the list, but due to the unusually high number of febrile side effects reported in in Australia in children under five, this product will receive new package warnings and will not be distributed in the .25ml single dose syringes normally used for vaccinating young children.

This year the CDC is urging nearly-universal vaccination for those over the age of 6 months (see CIDRAP CDC launches universal flu vaccination recommendation).

You can read the FDA Press release for more details at the link below:

FDA NEWS RELEASE

For Immediate Release:  July 30, 2010
Media Inquires:  Shelly Burgess, 301-796-4651, shelly.burgess@fda.hhs.gov
Consumer Inquiries:  888-INFO-FDA, OCOD@fda.hhs.gov

FDA Approves Vaccines for the 2010-2011 Influenza Season

The U.S. Food and Drug Administration announced today that it has approved vaccines for the 2010-2011 influenza season in the United States.

 

Seasonal influenza vaccine protects against three strains of influenza, including the 2009 H1N1 influenza virus, which caused the 2009 pandemic. Last year because the 2009 H1N1 virus emerged after production began on the seasonal vaccine, two separate vaccines were needed to protect against seasonal flu and the 2009 H1N1 pandemic flu virus, but this year, only one vaccine is necessary.

 

According to the Centers for Disease Control and Prevention (CDC), between 5 percent and 20 percent of the U.S. population develops influenza each year, leading to more than 200,000 hospitalizations from related complications and about 36,000 deaths.

 

“The best way to protect yourself and your family against influenza is to get vaccinated every year,” said Karen Midthun, M.D., acting director of FDA’s Center for Biologics Evaluation and Research. “The availability of a new seasonal influenza vaccine each year is an important tool in the prevention of influenza related illnesses and death.”

 

In addition to the important role that health care providers play in recommending influenza vaccination for their patients, influenza vaccination of health care personnel is important to protect themselves, their patients, their family, and the community from influenza. FDA urges health care organizations to encourage their members to get vaccinated.

(Continue . . . )

I’ve been accustomed to checking WHO | Situation updates - Pandemic (H1N1) 2009 every Friday for the latest survey of swine flu around the world. It hasn’t been very informative, and WHO persists in presenting its news in great long dull unreadable paragraphs, but it’s the most reliable information we’ve got.

WHO has published its latest Cumulative Number of Confirmed Human Cases of Avian Influenza A/(H5N1): 502 cases, 298 of them fatal, since 2003, for a worldwide case fatality ratio of 59.3 percent.

Via PLoS ONE, a report from Portuguese researchers: Influenza Infectious Dose May Explain the High Mortality of the Second and Third Wave of 1918–1919 Influenza Pandemic. The abstract:

Background 

It is widely accepted that the shift in case-fatality rate between waves during the 1918 influenza pandemic was due to a genetic change in the virus. In animal models, the infectious dose of influenza A virus was associated to the severity of disease which lead us to propose a new hypothesis. We propose that the increase in the case-fatality rate can be explained by the dynamics of disease and by a dose-dependent response mediated by the number of simultaneous contacts a susceptible person has with infectious ones. 

Methods 

We used a compartment model with seasonality, waning of immunity and a Holling type II function, to model simultaneous contacts between a susceptible person and infectious ones. In the model, infected persons having mild or severe illness depend both on the proportion of infectious persons in the population and on the level of simultaneous contacts between a susceptible and infectious persons. We further allowed for a high or low rate of waning immunity and volunteer isolation at different times of the epidemic. 

Results 

In all scenarios, case-fatality rate was low during the first wave (Spring) due to a decrease in the effective reproduction number. The case-fatality rate in the second wave (Autumn) depended on the ratio between the number of severe cases to the number of mild cases since, for each 1000 mild infections only 4 deaths occurred whereas for 1000 severe infections there were 20 deaths. A third wave (late Winter) was dependent on the rate for waning immunity or on the introduction of new susceptible persons in the community. If a group of persons became voluntarily isolated and returned to the community some days latter, new waves occurred. For a fixed number of infected persons the overall case-fatality rate decreased as the number of waves increased. This is explained by the lower proportion of infectious individuals in each wave that prevented an increase in the number of severe infections and thus of the case-fatality rate. 

Conclusion 

The increase on the proportion of infectious persons as a proxy for the increase of the infectious dose a susceptible person is exposed, as the epidemic develops, can explain the shift in case-fatality rate between waves during the 1918 influenza pandemic.

(Fri, 30 Jul 2010 14:28:00 +0000)

# 4771

CSL, Ltd produces influenza vaccines for Australia, and for export to other countries.  In some cases those vaccines are marketed - and re-labeled – by other companies.

The UK is among the importers of CSL’s flu vaccine, which earlier this year was been linked to a higher than normal incidence of febrile side effects in children under the age of five.  

 

Pfizer markets the CSL vaccine under the name Enzira while CSL Biotherapies sells it as a generic influenza vaccine.

Doctors in the UK are being urged by the DOH to use the CSL/Pfizer vaccines for those over the age of five.

Healthcare Republic has the story at the link below.  

Flu jabs from CSL and Pfizer not for under fives, DoH warns

Tom Moberly, healthcarerepublic.com, 29 July 2010, 10:49am

You’ll I posted another story on the CSL vaccine earlier today in  Australia Lifts Ban On Flu Vax For Under Five’s.

Via BeritaJakarta.com: Thousands of poultry culled in East Jakarta. Excerpt:

East Jakarta Municipal Administration is very serious to protect its citizens from the threat of the H5N1 virus of bird flu. It can be seen from the number of poultry of various types culled by the local husbandry and fishery agency from January until July 2010, reaching 1,309. 

The thousands of destroyed poultry consisted of 524 chickens, 345 ducks, and 440 pigeons. Of the number, most destroyed poultry was recorded in Kramatjati sub-district (403), followed by Cakung (195), Cipayung (179), Pasarrebo (130), Jatinegara (106), Pulogadung (102), Ciracas (65), Durensawit (63), Makassar (59), and Matraman (7). In the poultry destruction procedure, the slaughtered poultry are returned to the owners. 

In addition to culling poultry, the officers also dismantle and burn poultry cages located within a radius of several meters from residential areas. It is considered necessary to reassure that public are really free from poultry. These measures are in line with Bylaw No.4/2007 on Poultry Control and Distribution in Jakarta area. 

Head of the agency Ahmad Adnan explains every citizen who lives in Jakarta is banned from raising poultry within a radius of 25 meters from residential areas. “Our officers will directly take action on poultry roaming in residential areas,” said Adnan, Friday (7/30).

Restoring the dead birds to their owners might seem bizarre, but these were healthy birds—they were just being kept in the wrong place.

(Fri, 30 Jul 2010 12:48:00 +0000)

# 4770

A little over a week ago I wrote about `triple E’, or Eastern Equine Encephalitis, which had claimed the life of a Hillsborough County (Florida) woman earlier this month.

 

While exceedingly rare, Florida sees on average 1 or 2 (range 0-5) human cases each year, and about 70 equine infections.   

 

Nationally, between 1999 and 2008 there were a median of seven (range: 3–21) EEE cases (not deaths) reported in the United States each year.

So the unusual news yesterday of another death in the same county – this time of an infant -  has prompted the local health department to upgrade a mosquito advisory issued last April to a full Alert.

This is the third death this month in Florida from the virus, as earlier this month a retired postal worker in the panhandle (Wakulla County) also succumbed to the virus.

The St. Petersburg Times has the story.

Brandon infant dies of equine encephalitis

Friday, July 30, 2010

As the chart below shows, the months of June-July-August historically produce the most human cases of EEE in Florida, with July by far seeing the most.

Still, the average for the month of July over the past 50 years has been less than 1 case per year.

The Florida Department of Health reminds residents that to help protect themselves against mosquito borne diseases they should practice the “5 D’s”

Don’t go outdoors at DUSK and DAWN when mosquitoes are most active.

 

DRESS so your skin is covered with clothing

 

Apply mosquito repellent containing DEET to bare skin and clothing. 

Other effective repellents include picaridin, oil of lemon eucalyptus, and IR3535

Empty containers and DRAIN standing water around your home where mosquitoes can lay eggs.

For more details visit the Florida DOH Mosquito-borne Disease Prevention webpage.  

And for a good deal more background on EEE - including a link to a terrific slideshow narrated by by Rebecca Shultz, the Arthropod-borne Disease Surveillance Coordinator for the Florida Department of Health, on mosquito borne diseases -  you might want to check out my earlier essay:

Eastern Equine Encephalitis (EEE)

And of course, over the past year, a small number of Dengue Fever cases have turned up in Florida as well.  Of these, 45 are imported cases, while 19 cases are believed to be locally acquired.

Update On The Florida Dengue Cases

In addition West Nile virus (WNV), La Crosse virus (LACV), and St. Louis encephalitis virus (SLEV) also circulate at very low levels in the United States. 

So these precautions against mosquitoes aren’t just important for Floridians to heed.