H1N1 Anti-Virals vs Vaccines, York Study

Burch et al (August, 2009) conducted a study of study of a number of anti-viral drugs used for treatment of seasonal influenza and noted the debatable clinical importance of these drugs upon symptom duration. The authors advocated appropriate vaccination policy. URL: [http://press.thelancet.com/tlidantivirals.pdf].

H1N1 Anti-Virals vs Vaccines, Oxford Study

News Reports claim that Oxford (UK) researchers including Dr Carl Henegan and Mathew Shun Shin have conducted ‘a systemic review of data from published and unpublished randomized controlled trials using anti-virals in children younger than 12 years’. These researchers found that anti-virals including Tamiflu and Relenza ‘provided a small benefit by shortening the duration of seasonal influenza in children and reducing household transmission whilst they have little effect on asthma exacerbation’. URL: [http:/www.upi.com/Health_News/2009/08/10/Tamiflu-anti-virals-may-not-help-children/UPI-80391249926430/]. According to a news report, Dr Carl Henegan stated the current policy of giving Tamiflu for mild illness was an inappropriate strategy. URL: [http://www.telegraph.co.uk/health/swine-flu/6006588/Children-should-not-be-given-Tamiflu-Oxford-researchers.html]. However, a UK Health Department official spokesperson dismissed the claims of these researchers. Alternatively, the Indian government is currently considering retail sales of Tamiflu. URL: [http://economictimes.indiatimes.com/News/News-By-Industry/Healthcare-Biotech/Govt-may-allow-retail-sales-of-H1N1-drug/articleshow/4875512.cms]

Influenza A viruses

Danielle Focosi (2001-2005) writes on Influenza A viruses. This includes 1) epidemiology 2) genomics 3) proteomics 4) transmission 5) pathogenesis 6) signs and symptoms and 7) prevention – URL: [http://focosi.altervista.org/pathoviruses_influenzaA.html].

Extinction of domestic animals

At this time it may be worthwhile to reflect upon the rate of extinction of domestic animals. Notably, whilst pigs and chickens are carriers of influenza viruses that can affect humans, farmers reportedly rely on the fewest varieties of these animals for food production. Perhaps more species of pigs and chickens should be protected from extinction and used within these industries, if necessary. You can read about this point at: URL:- [http://www.infoplease.com/spot/farmanimals1.html]

NSW pigs infected with H1N1 or A H1 virus?

It was reported in the media yesterday that pigs in the town of Dunedoo, Central New South Wales, have been infected with an influenza virus transmitted by humans:- URL:[http://www.smh.com.au/national/swine-flu-shuts-hospital-as-pigs-get-virus-20090801-e53z.html]. According to Mark O’Brien’s report in the Sydney Morning Herald ‘tests confirmed the pigs had influenza A H1 , which is different to the human swine flu virus’. Whereas the ABC’s report on Friday, July 31st, 2009, claims that ‘tests have confirmed that swine flu has broken out at a piggery in the central west of New South Wales’:- URL: [http://www.abc.net.au/news/stories/2009/07/31/2642757.htm]. It appears these infected pigs may have Influenza H1N1 (Swine flu) or they may have a different virus, for example, A H1 influenza.

Antigenic Shift

According to this simple diagram located at URL: [http://jphpk.gov.my/English/AntigenicShift_HiRes.png] ‘the genetic change that enables a flu strain to jump from one animal species to another, including humans, is called Antigenic Shift’. It’s interesting that the presence of a bird strain of Influenza A is involved in this outlined process. According to this above-mentioned diagram, ‘when the viruses infect the same cell in a pig, the genes from the bird strain mix with the genes from the human strain to yield a new strain’. This raises the question as to whether the infected H1N1 pigs in Central New South Wales already infected with a bird strain of Influenza A?

‘Protect Phase’ W.A. Guidelines

On 9th July, 2009, the Western Australian Government updated guidelines for management of H1N1 Influenza. These guidleines include: 1) Minimise transmission of the virus 2) Identify and treat the vulnerable early 3) Management of contacts 4) Follow-up of positive case, notification of negative cases 5) Public messaging – H1N1 is a mild disease in most cases. URL: http://www.public.health.wa.gov.au/cproot/2378/2/SwineFluGuideline-Hospitals%209%20July%202009.pdf

Clinical Scenerios that Need Special Attention

On the 14th July, 2009, the Taranaki District Health Board, New Zealand, published a GP Update for Non-seasonal Influenza A (H1N1) including guidelines for infants and children (Version 1). According to this paper, Influenza presents in infancy and childhood as a wide variety of clinical syndromes. In addition, presentations may include ‘ i) Fever and misery ii) Bronchiolitis iii) Asthma exacerbation iv) Acute otitis media v) Lower respiratory infection vi) Convulsion with fever vii) Dehydration viii) Fever, lethargy, irritability meningitis not excluded ix) Toxic bacteraemic type illness x) Apnoea xi) Diabetic instability’. Furthermore:

‘Four Life Threatening Clinical Scenerios that Need Special Attention may include:

1) Vulnerable infant developing Bronchiolitis Picture

2) Early rapidly progressive respiratory distress

3) Late onset deterioration in respiratory status

4) Influenza encephalitis’

References include:

URL:

http://www.cdc.gov/h1n1flu/clinicians/

Friedman, M.J. & Attia, M.W. (2004). Clinical predictors of influenza in children. Arch Pediatr Adolesc, Med. 2004; 158:391-394

Effectiveness of handwashing protocols against H1N1

Grayson, Melvani, Druce, Barr, Ballard, Johnson, Mastorakos, and Birch’s (2009) study of handwashing protocols assesses of the comparative efficacy of various handwashing protocols including use of i) Non-medicated liquid soap ii) 61.5% Ethanol plus skin emollient iii) 70% Isopropyl alcohol plus 0.5% chlorhexidine plus skin emollient and iv) 70% Ethanol plus 0.5% chlorhexidine plus skin emollient. These four hand hygiene protocols as used in Australian clinical settings were all found to be highly effecitive in achieving a large reduction in H1N1 from human hands. Non-medicated soap and water was found to be the most effective hand hygiene product to use.

Reference:

Grayson, M.L. et al. (2009). Efficacy of Soap and Water and Alcohol-Based Hand-Rub Preparations against Live H1N1 Influenza Virus on the Hands of Human Volunteers, Clinical Infectious Diseases, 2009, 48: 285-91.

H1N1 Influenza

I have blogged at http://nursenetwork.edublogs.org/ on this issue.