Monday, August 31, 2009

WHO update

The lastest WHO briefing note has a few key points to notice:

  • Early studies show a higher risk of hospitalization and death among minority groups and indigenous populations—four to five times higher than the general population in some studies.
  • Early data from two countries suggest that people infected with both HIV and novel H1N1 are not at increased risk for severe illness, provided they are on antiretroviral therapy.
  • H1N1 viruses from all outbreaks are virtually identical, showing no signs of dangerous mutations.

http://www.who.int/csr/disease/swineflu/notes/h1n1_second_wave_20090828/en/index.html

Sinovac's novel H1N1 flu vaccine passes evaluation in China

Reuters is reporting on the first novel H1N1 to pass the test of a regulatory body, Sinovac's vaccine in China:

"The experts agreed that Sinovac's H1N1 vaccine is applicable to people from 3 years to 60 years old and the vaccination schedule is a single shot, the company said in a statement.
The company expects to obtain production license for its vaccine within a week.

Sinovac said the result of the experts' evaluation conference will be submitted to China's State Food and Drug Administration (SFDA), on Sept. 1 and is expected to be the primary opinion for SFDA to issue the production license.

Earlier this month, Sinovac, which is the first company worldwide to complete clinical trials for a vaccine to treat strain of H1N1, said a single dose of its H1N1 vaccine is effective and sufficient."

Thursday, August 13, 2009

WHO update on the spread of H1N1

Great update from WHO on the global spread and incidence of novel H1N1. Here's the most important exceprt,

"This season, pandemic H1N1 has been the predominant influenza virus in nearly all of the temperate regions of Southern Hemisphere, with South Africa being a notable exception. Australia and countries in the southern part of South America experienced rapid increases in cases of pandemic influenza early in their winter season. These same areas are now starting to report decreases in the numbers of people seeking care and being admitted to hospital. Although the virus is still circulating in these areas as it moves into areas not affected earlier, the overall national trends are downward. South Africa, in contrast, experienced an early influenza season with a seasonal subtype, influenza A (H3N2). As the influenza season in South Africa reached its peak in early to mid June and began to decline, pandemic influenza H1N1 appeared and has now become the dominant subtype seen there as well...

In the temperate areas of the northern hemisphere which experienced early outbreaks of pandemic H1N1 influenza, including countries in North America and Europe, the virus continues to spread to new areas and cause intense local outbreaks. However, the overall national trend in cases is downward in the Americas...


Tropical regions of the world, which typically experience year round transmission of influenza viruses with peak transmission at different and often multiple times in a year, are now seeing increases in cases, for example in tropical areas of Central and South America and in South and South East Asia.

In summary, the overall picture of transmission globally is one of declining transmission in the temperate regions of the Southern Hemisphere with the exception of southern Africa."



http://www.who.int/csr/don/2009_08_12/en/index.html

Tuesday, August 11, 2009

Do antivirals work on children?

Yesterday in the media there were several reports about antivirals being less effective for children. This was in response to a new BMJ paper that was a meta analysis on other studies.

However, there's probably less new information here than might appear from media reports. We already knew that antivirals were not necessarily a panacea for flu. The study basically reinforces that - antivirals work, but they're not always that great.

Effect Measure, a highly respected public health blog, wrote on the subject today:

"Antivirals aren't like antibiotics, where you can sometimes work almost miraculous cures. If they work, they work at the margins. With those prejudices of mine as background, I can state that one clear message of the 2005 review and this one is that both of these drugs work to some extent. You wouldn't get that idea at all if all you read was the news headlines (the BBC again: Flu drugs 'unhelpful' in children). They not only work, but they work on every single measure examined: reduction of time with symptoms (.5 days to 1.5 days); time of illness (.4 days to 1.5 days), where this was defined as resolution of all symptoms and resolution of fever and return to school or normal activities; reduction in cough or fever (1.3 days for Tamiflu, "reduced incidence of moderate or severe cough" at day five with Relenza); reduction in asthma exacerbation; improvement in pulmonary function; reduction in antibiotic use; reduction in otitis media (middle ear infection) at day 10; and in confirmed secondary cases with an infected index case (reduction in transmission of about 8%)."

I highly recommend the whole blog here:

http://scienceblogs.com/effectmeasure/2009/08/flu_antivirals_the_good_news_t.php

Monday, August 10, 2009

CDC shortens the length of time people with flu symptoms should stay home

CDC has revised guidance on how long people with flu symptoms should stay home,

"The new exclusion guidance urges people with influenza-like illnesses to stay home at least 24 hours after they are free of a fever (in the absence of fever-reducing medication), defined as 100°F, which in most cases ranges from 3 to 5 days.

Earlier recommendations urged people to stay home for 7 days after illness onset or for 24 hours after symptoms resolve, whichever was longer. Besides businesses and schools, the guidance also applies to camps, mass gatherings, and other community settings.

However, the new recommendations do not apply to healthcare settings. People working or visiting healthcare facilities should still observe the earlier, longer-period exclusion guidance"

For the full article:
http://www.cidrap.umn.edu/cidrap/content/influenza/swineflu/news/aug0609absence-jw.html

Wednesday, August 5, 2009

Drugmakers begin vaccine trials

While CSL in Australia began pandemic vaccine trials two weeks ago, other drug companies are also gearing up. Reuters is reporting that Novartis is beginning tests of their pandemic vaccine. Sanofi will start trials soon and Glaxo and AstraZeneca will begin trials later this month.

One bit of good news burried in the article,

"Initially, all the manufacturers except MedImmune -- which uses a different process -- struggled with low yields when making swine flu vaccine, with most companies only getting about 30 percent of the usual yield of seasonal flu strains.

But that is starting to improve.

"We are higher than that (30 percent)," Sanofi's Rungeard said."

Read the full article here: http://www.reuters.com/article/swineFlu/idUSL459625620090804?feedType=RSS&feedName=swineFlu&virtualBrandChannel=10521&pageNumber=2&virtualBrandChannel=0

WHO pandemic update

WHO has urged countries with significant transmission to stop testing and reporting individual cases of novel H1N1 influenza. WHO is still posting numbers, but notes that given the shift in surveillance strategies, these will be severe underestimates. (http://www.who.int/csr/don/2009_08_04/en/index.html)

"As of 31 of July 2009, 168 countries and overseas territories/communities have reported at least one laboratory confirmed case of pandemic (H1N1) 09. All continents are affected by the pandemic.

The countries and overseas territories/communities that have newly reported their first pandemic (H1N1) 2009 confirmed case(s) since the last web update (27 July 2009) as of 31 July 2009 are:

Azerbaijan, Gabon, Grenada, Kazakhstan, Moldova, Monaco, Nauru, Swaziland, Suriname

Region

Cumulative total

as of 31 July 2009



Cases*

Deaths


WHO Regional Office for Africa (AFRO)

229

0


WHO Regional Office for the Americas (AMRO)

98242

1008


WHO Regional Office for the Eastern Mediterranean (EMRO)

1301

1


WHO Regional Office for Europe (EURO)

26089

41


WHO Regional Office for South-East Asia (SEARO)

9858

65


WHO Regional Office for the Western Pacific (WPRO)

26661

39



Grand Total

162380

1154

WHO statement on pregnant women and pandemic flu

"31 JULY 2009 | GENEVA -- Research conducted in the USA and published 29 July in The Lancet [1] has drawn attention to an increased risk of severe or fatal illness in pregnant women when infected with the H1N1 pandemic virus.

Several other countries experiencing widespread transmission of the pandemic virus have similarly reported an increased risk in pregnant women, particularly during the second and third trimesters of pregnancy. An increased risk of fetal death or spontaneous abortions in infected women has also been reported.

Increased risk for pregnant women

Evidence from previous pandemics further supports the conclusion that pregnant women are at heightened risk.

While pregnant women are also at increased risk during epidemics of seasonal influenza, the risk takes on added importance in the current pandemic, which continues to affect a younger age group than that seen during seasonal epidemics.

WHO strongly recommends that, in areas where infection with the H1N1 virus is widespread, pregnant women, and the clinicians treating them, be alert to symptoms of influenza-like illness.

WHO recommendations for treatment

Treatment with the antiviral drug oseltamivir should be administered as soon as possible after symptom onset. As the benefits of oseltamivir are greatest when administered within 48 hours after symptom onset, clinicians should initiate treatment immediately and not wait for the results of laboratory tests.

While treatment within 48 hours of symptom onset brings the greatest benefits, later initiation of treatment may also be beneficial. Clinical benefits associated with oseltamivir treatment include a reduced risk of pneumonia (one of the most frequently reported causes of death in infected people) and a reduced need for hospitalization.

WHO has further recommended that, when pandemic vaccines become available, health authorities should consider making pregnant women a priority group for immunization.

Danger signs in all patients

Worldwide, the majority of patients infected with the pandemic virus continue to experience mild symptoms and recover fully within a week, even in the absence of any medical treatment. Monitoring of viruses from multiple outbreaks has detected no evidence of change in the ability of the virus to spread or to cause severe illness.

In addition to the enhanced risk documented in pregnant women, groups at increased risk of severe or fatal illness include people with underlying medical conditions, most notably chronic lung disease (including asthma), cardiovascular disease, diabetes, and immunosuppression. Some preliminary studies suggest that obesity, and especially extreme obesity, may be a risk factor for more severe disease.

Within this largely reassuring picture, a small number of otherwise healthy people, usually under the age of 50 years, experience very rapid progression to severe and often fatal illness, characterized by severe pneumonia that destroys the lung tissue, and the failure of multiple organs. No factors that can predict this pattern of severe disease have yet been identified, though studies are under way.

Clinicians, patients, and those providing home-based care need to be alert to danger signs that can signal progression to more severe disease. As progression can be very rapid, medical attention should be sought when any of the following danger signs appear in a person with confirmed or suspected H1N1 infection:

  • shortness of breath, either during physical activity or while resting
  • difficulty in breathing
  • turning blue
  • bloody or coloured sputum
  • chest pain
  • altered mental status
  • high fever that persists beyond 3 days
  • low blood pressure.

In children, danger signs include fast or difficult breathing, lack of alertness, difficulty in waking up, and little or no desire to play.

________________________________

[1] Jamiesan DG et al. H1N1 2009 influenza virus infection during pregnancy in the USA. Lancet 2009; published online July 29, 2009"





http://www.who.int/csr/disease/swineflu/notes/h1n1_pregnancy_20090731/en/