td_module_mega_menu Object ( [authorType] => [post] => WP_Post Object ( [ID] => 10656 [post_author] => 235 [post_date] => 2020-07-01 14:58:45 [post_date_gmt] => 2020-07-01 04:58:45 [post_content] => Nearly all Australian pharmacies are now registered for the My Health Record, following an increase in the use of technology brought about by the COVID-19 pandemic.
td_module_mega_menu Object ( [authorType] => [post] => WP_Post Object ( [ID] => 10649 [post_author] => 1703 [post_date] => 2020-07-01 14:34:59 [post_date_gmt] => 2020-07-01 04:34:59 [post_content] => While the rest of Australia maintains low rates of COVID-19 infection, 36 suburbs in Victoria will enter lockdown from midnight tonight as case numbers continue to rise.
td_module_mega_menu Object ( [authorType] => [post] => WP_Post Object ( [ID] => 10640 [post_author] => 23 [post_date] => 2020-07-01 14:09:42 [post_date_gmt] => 2020-07-01 04:09:42 [post_content] => Queensland women now have access to immediate advice and treatment, including the supply of antibiotics when appropriate, for uncomplicated urinary tract infections (UTIs) through their participating community pharmacy.
td_module_mega_menu Object ( [authorType] => [post] => WP_Post Object ( [ID] => 10569 [post_author] => 227 [post_date] => 2020-06-24 14:19:29 [post_date_gmt] => 2020-06-24 04:19:29 [post_content] =>
In line with Therapeutic Goods Administration (TGA) regulatory changes to enhance medicine safety, PSA has developed a cautionary advisory label (CAL) that warns consumers about the risk of opioid overdose and dependence.
The CAL (Label 24, at right) can be applied to opioid medicines at the time of dispensing as an aid to counselling patients about the safe and effective use of opioids. An Opioid medicines patient information handout has been developed as a counselling aid.
The CAL is recommended for opioid medicines, including buprenorphine, codeine, dihydrocodeine, fentanyl, hydromorphone, methadone, morphine, oxycodone, tapentadol, and tramadol.
Pharmacists are advised to provide the Opioid medicines patient information handout to any patient receiving opioid medicine that carries Label 24.
Two rolls of Label 24, a copy of the patient handout and a letter to pharmacists were posted this month to all community and hospital pharmacies.PSA General Manager Knowledge Development Stefanie Johnston MPS said the CAL could help pharmacists speak to their patients about medicine safety. ‘Label 24 provides a new opportunity to have open conversations with your patients about the safe use of opioids,’ she said. ‘I encourage all pharmacists to incorporate it into their practice.’
CPD material about Label 24, the patient handout, TGA opioid regulatory reforms and safe and effective use of opioids has been developed by both PSA and the Society of Hospital Pharmacists of Australia and is expected to be available from next month.
Emeritus Professor Lloyd Sansom AO FPS, chair of the Australian Pharmaceutical Formulary and Handbook (APF) editorial board, chaired the stakeholder roundtable meeting that led to the development of the CAL and patient handout.[caption id="attachment_9769" align="alignright" width="356"] Lloyd Sansom FPS[/caption]
As chair of the editorial board as well as the APF’s New Drugs Advisory Group (NDAG), Professor Sansom has approved publication of both documents in the APF.
The CAL and patient handout were reviewed by the 10 pharmacist members of the APF NDAG as well as the Professor of Medicines Use Optimisation at the University of Sydney School of Pharmacy Parisa Aslani FPS.
Professor Aslani has expertise in patient counselling and education, including consumer medicines information (CMI).
The new TGA regulations require opioid sponsors to update prescribing indications for opioids to ensure patients are prescribed opioids only where the benefits outweigh the risks.
They also require sponsors to add additional warning statements to Product Information and CMI for all opioids. This is so prescribers and consumers are reminded of the appropriate circumstances for opioid prescribing and potential adverse effects.
Sponsors must also now register smaller pack sizes for immediate-release opioids that provide a more appropriate option for short-term pain relief.
Exisiting larger pack sizes will remain available for patients who need them.
For more information, visit www.tga.gov.au/alert/prescription-opioids.[post_title] => New Label 24 to help pharmacists reduce opioid risks [post_excerpt] => In line with TGA regulatory changes to enhance medicine safety, PSA has developed a cautionary advisory label that warns consumers about the risk of opioid overdose and dependence. [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => new-opioid-cautionary-advisory-label-available [to_ping] => [pinged] => https://www.australianpharmacist.com.au/pbs-changes-prescription-opioids/ [post_modified] => 2020-06-25 15:08:50 [post_modified_gmt] => 2020-06-25 05:08:50 [post_content_filtered] => [post_parent] => 0 [guid] => https://www.australianpharmacist.com.au/?p=10569 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [title_attribute] => New Label 24 to help pharmacists reduce opioid risks [title] => New Label 24 to help pharmacists reduce opioid risks [href] => https://www.australianpharmacist.com.au/new-opioid-cautionary-advisory-label-available/ [module_atts:td_module:private] => Array ( ) [td_review:protected] => Array ( ) [is_review:protected] => [post_thumb_id:protected] => 10580 )
td_module_mega_menu Object ( [authorType] => [post] => WP_Post Object ( [ID] => 10574 [post_author] => 1703 [post_date] => 2020-06-24 14:01:44 [post_date_gmt] => 2020-06-24 04:01:44 [post_content] => A cheap and widely used corticosteroid may be employed in Australia in the treatment of seriously ill COVID-19 patients. Following preliminary results of a UK trial conducted by researchers at the University of Oxford and released by the World Health Organisation last week, Federal Health Minister Greg Hunt said there were ‘no barriers’ to the use of dexamethasone for COVID-19 treatment. ‘It’s not going to prevent you getting it, it’s not going to cure it, but the early, but [sic] high-quality evidence out of the UK is that [for] people who are very, very sick, it gives them a much better chance of survival,’ he told a Sydney radio station. Commenced in March, the Randomised Evaluation of COVID-19 Therapy (RECOVERY) trial is one of the world’s largest randomised, controlled trials for coronavirus treatments. Dexamethasone was found to reduce deaths in patients with COVID-19 by a third in ventilated patients and a fifth in other patients receiving oxygen. No benefit was reported among patients who did not require respiratory support. There are currently just three people in Australian intensive care units due to COVID-19, all of them in Victoria, which is currently experiencing an increase in the number of new cases.
A need for cautionPeer review of clinical data is still required prior to any recommendations being made by the National COVD-19 Clinical Evidence Taskforce about the use of dexamethasone. However, in a statement, the taskforce acknowledged that the preliminary results were promising and said it was hopeful the benefits would be confirmed in a peer-reviewed publication in the very near future. ‘At this time, the living evidence approach employed by the taskforce will enable us to respond rapidly to provide evidence-based recommendations about the use of dexamethasone in COVID-19,’ the statement said. Program Director of Undergraduate Pharmacy at the University of Sydney Associate Professor Nial Wheate told Australian Pharmacist that the medical community was aware of criticism that could surround publishing drug study results too early. Substantial concerns were raised by the global research community regarding the integrity of data published in The Lancet last month about the potential benefits of hydroxychloroquine in relation to COVID-19. A/Prof Wheate added that while exercising initial caution, it was also necessary to consider the side effects of dexamethasone and to ensure members of the public were aware it helped mitigate one of the symptoms of COVID-19 infection – lung inflammation – rather than treat the virus itself. ‘One of the potential risks is that it could make patients more susceptible to other diseases in a hospital setting because it is a steroidal medication that suppresses immunity,’ he said.
Managing demandThe initial outbreak of COVID-19 in Australia resulted in a high demand for drugs that had been publicised in the media or discovered on the internet. The Therapeutic Goods Administration (TGA) is eager to avoid a similar situation involving dexamethasone. It said there is currently no national shortage of dexamethasone injection or tablets and that demand for the medicines is being monitored. The TGA also cautioned that the RECOVERY trial reportedly showed benefit only for ventilated or oxygenated COVID-19 patients in hospital, not for mild cases or prophylactic use. Researchers involved in the RECOVERY trial are also looking at drugs including lopinavir–ritonavir, azithromycin and tocilizumab as possible treatments for patients admitted to hospital with COVID-19. [post_title] => Dexamethasone and COVID-19 [post_excerpt] => A cheap and widely used corticosteroid may be employed by Australian doctors in the treatment of seriously ill COVID-19 patients. [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => dexamethasone-covid-19 [to_ping] => [pinged] => https://www.australianpharmacist.com.au/who-temporary-pause-hydroxychloroquine-trial-coronavirus/ [post_modified] => 2020-06-29 20:47:56 [post_modified_gmt] => 2020-06-29 10:47:56 [post_content_filtered] => [post_parent] => 0 [guid] => https://www.australianpharmacist.com.au/?p=10574 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [title_attribute] => Dexamethasone and COVID-19 [title] => Dexamethasone and COVID-19 [href] => https://www.australianpharmacist.com.au/dexamethasone-covid-19/ [module_atts:td_module:private] => Array ( ) [td_review:protected] => Array ( ) [is_review:protected] => [post_thumb_id:protected] => 10576 )
td_module_mega_menu Object ( [authorType] => [post] => WP_Post Object ( [ID] => 10538 [post_author] => 1092 [post_date] => 2020-06-22 08:30:16 [post_date_gmt] => 2020-06-21 22:30:16 [post_content] => [vc_row][vc_column width="2/3"][vc_column_text]When Paul Karason died of a heart attack in 2013, age 62, few noticed. But he had achieved global infamy in 2008 when he appeared on the US morning TV show Today.
The uglyWhy? Mr Karason was blue, literally blue. Persuaded of the healing powers of colloidal silver – minute silver particles suspended in a liquid – Mr Karason concocted and consumed his own brew of water and silver nanoparticles. After several years, he developed an irreversible condition called argyria, a blue-grey discolouration of the skin.1,2 Because of his daily dosing, the silver particles accumulated, ionised in his stomach and were transported to the skin. There they reacted with sunlight, causing the blue discolouration.2 Mr Karason was not alone in his misbelief. Celebrities such as Gwyneth Paltrow espoused alleged health benefits from ingesting colloidal silver. The supposed benefits range from boosting the immune system to treating cancer, HIV/AIDS, shingles, herpes, eye ailments and prostatitis.1,3 However, no rigorous studies supporting these claims exist.3
The badWorse, as Mayo Clinic physician and researcher Dr Brent Bauer notes: ‘Excessive doses of colloidal silver can cause possibly irreversible serious health problems, including kidney damage and neurological problems such as seizures’. Heavy ingestion can also cause bone marrow suppression, hepatotoxicity and acute tubular necrosis. Colloidal silver products also interact with some medicines.2,3 Little wonder, then, that in 1999 the US Food and Drug Administration ruled that products containing colloidal silver ingredients or silver salts were neither safe nor effective.4 Similarly, in 2002 the Therapeutic Goods Administration (TGA) concluded: ‘There are no colloidal silver products approved for supply as medicines in Australia.’5 Both the TGA and the US Health Department’s National Center for Complementary and Integrative Health note that while unsupported by evidence, products marketed as ‘dietary supplements’ are available online.4-6
The goodSilver was once widely used. In AD 78, Pliny the Elder reported that slag from smelting silver ‘has healing properties as an ingredient in plasters’. According to Herodotus, Cyrus the Great – king of Persia from 550 BC to 529 BC – stayed healthy by drinking only boiled water stored in silver flagons. During the Middle Ages, monks popularised the use of silver nitrate, a salt formed by reacting silver with nitric acid, to treat ulcers and burns.1,7 As early advocates observed, silver does have antiseptic properties. Until the advent of antibiotics, it was used topically with variable success.8 The exact mechanism by which silver attacks bacterial cells is unclear. Scientists suggest the key is the biocidal effect of heavy metals such as silver. They kill microbes by binding to proteins, thus inhibiting enzymatic activity.9 Today, the biocidal effect is being harnessed anew. Although thorough testing and standardisation of products has not yet been undertaken, silver-containing coatings on medical devices and fabrics can have clinical uses.9 Among these uses are: wound care, bone prostheses, reconstructive orthopaedic surgery, cardiac devices, catheters, surgical appliances and, of relevance to COVID-19, ventilators.10 References
[/vc_column_text][/vc_column][vc_column width="1/3"][/vc_column][/vc_row] [post_title] => The good, the bad and the ugly: Colloidal silver and its chequered history [post_excerpt] => Celebrities such as Gwyneth Paltrow espoused alleged health benefits from ingesting colloidal silver. However, no rigorous studies supporting these claims exist. [post_status] => publish [comment_status] => open [ping_status] => open [post_password] => [post_name] => colloidal-silver-chequered-history [to_ping] => [pinged] => [post_modified] => 2020-06-29 21:51:35 [post_modified_gmt] => 2020-06-29 11:51:35 [post_content_filtered] => [post_parent] => 0 [guid] => https://www.australianpharmacist.com.au/?p=10538 [menu_order] => 0 [post_type] => post [post_mime_type] => [comment_count] => 0 [filter] => raw ) [title_attribute] => The good, the bad and the ugly: Colloidal silver and its chequered history [title] => The good, the bad and the ugly: Colloidal silver and its chequered history [href] => https://www.australianpharmacist.com.au/colloidal-silver-chequered-history/ [module_atts:td_module:private] => Array ( ) [td_review:protected] => Array ( ) [is_review:protected] => [post_thumb_id:protected] => 10539 )
- Pickett, M. Colloidal silver turns you blue—but can it save your life? Wired 2017 Feb 10. At: www.wired.com/story/does-colloidal-silver-work/
- Bracy NA, Zipursky JK, Juurlink DN. Argyria caused by chronic ingestion of silver. CMAJ 2018;190(5):E139. At: www.cmaj.ca/content/190/5/E139.long
- Bauer BA. My dad takes colloidal silver for his health, but is it safe? Mayo Clinic. 2017. At: www.mayoclinic.org/healthy-lifestyle/consumer-health/expert-answers/colloidal-silver/faq-20058061
- US Food and Drug Administration. Over-the-counter drug products containing colloidal silver ingredients or silver salts. Fed Regist 1999;64(158):44653–8. At: www.ncbi.nlm.nih.gov/pubmed/10558603
- Therapeutic Goods Administration. Change to excluded goods order: Colloidal silver products. 19 December 2002. At: www.tga.gov.au/sites/default/files/foi-156-1213-25.pdf
- National Institutes of Health. National Center for Complementary and Integrative Health. Colloidal silver. At: www.nccih.nih.gov/health/colloidal-silver
- Alexander JW. History of the medical use of silver. Surg Infect 2009;10(3):289–92. At: www.liebertpub.com/doi/10.1089/sur.2008.9941
- Chopra I. The increasing use of silver-based products as antimicrobial agents: a useful development or a cause for concern? J Antimicrob Chemother 2007;59(4):587–90. At: pubmed.ncbi.nlm.nih.gov/17307768/
- Lumen Learning. Using Chemicals to Control Microorganisms. At: courses.lumenlearning.com/microbiology/chapter/using-chemicals-to-control-microorganisms/
- Lansdown A. Silver in health care: antimicrobial effect and safety in use. In: Biofunctional textiles and the skin. Hipler UC, Elsner P (eds). Curr Probl Dermatol Basel, Karger 2006;33:17–34. At: www.karger.com/Article/Abstract/93928
td_module_mega_menu Object ( [authorType] => [post] => WP_Post Object ( [ID] => 10519 [post_author] => 36 [post_date] => 2020-06-22 06:57:48 [post_date_gmt] => 2020-06-21 20:57:48 [post_content] => [vc_row][vc_column width="2/3"][vc_column_text]There are 344 registered interventional clinical trials under way for the treatment and prevention of COVID-19. The WHO is looking at four of them. At the time of press on 22 May, there are more than 5.2 million confirmed cases of novel coronavirus disease 2019 (COVID-19) around the world.1 COVID-19 is caused by the severe acute respiratory syndrome coronavirus (SARS-CoV-2).2 Approximately 80% of infections with clinical presentations will cause mild respiratory illness and people will recover without hospital care.3 Another 15% will present with moderate to severe pneumonia requiring hospital care, and 5% will need intensive care due to critical illness.3 At this stage, it is not known how many people are asymptomatic and infected. Additionally, it is unclear if succumbing to COVID-19 is a result of the virus itself or the innate immune response.4 Given the global emergency and the speed at which the virus has spread, drug repurposing has obvious advantages, particularly given the amount of time usually required to take a molecule from drug discovery to regulatory approval. Some of these agents have received more media interest than others, e.g. hydroxychloroquine (Plaquenil), following social media tweets by people such as US President Donald Trump. This led to excessive attempts to acquire the medicine, resulting in the introduction of restrictions to ensure supply only to those with a therapeutic need (e.g. rheumatoid arthritis, lupus). While numerous therapies are being tested all around the world, there are no pharmacological agents approved for either the treatment or prevention of COVID-19. In Australia, the consensus guidelines state: ‘For patients with COVID-19, only administer antiviral medications or other disease-modifying treatments in the context of clinical trials with appropriate ethical approval.’2 A recent review looked at the registered interventional clinical trials for the treatment and prevention of COVID-19.5 As of 20 March 2020, 344 studies were registered, of which 100 involved the use of traditional Chinese medicine, e.g. herbal medicines and acupuncture. The remainder include5:
td_module_mega_menu Object ( [authorType] => [post] => WP_Post Object ( [ID] => 10477 [post_author] => 23 [post_date] => 2020-06-17 11:13:30 [post_date_gmt] => 2020-06-17 01:13:30 [post_content] => The offspring of mothers exposed to extreme stress, undernutrition or infectious diseases during pregnancy are at heightened risk of psychosis, studies suggest.1
td_module_mega_menu Object ( [authorType] => [post] => WP_Post Object ( [ID] => 10393 [post_author] => 23 [post_date] => 2020-06-03 15:47:17 [post_date_gmt] => 2020-06-03 05:47:17 [post_content] => Changes to regulations on opioid supply in Australia came into effect this week, with new Pharmaceutical Benefits Scheme listings resulting in smaller quantities and restrictions around opioid prescribing for pain treatment.
td_module_mega_menu Object ( [authorType] => [post] => WP_Post Object ( [ID] => 10344 [post_author] => 23 [post_date] => 2020-05-27 12:18:46 [post_date_gmt] => 2020-05-27 02:18:46 [post_content] => For people with food allergies, medicines meant to benefit health can in fact present a risk due to food products used as inactive (excipient) ingredients.
td_module_mega_menu Object ( [authorType] => [post] => WP_Post Object ( [ID] => 10595 [post_author] => 140 [post_date] => 2020-06-29 21:33:38 [post_date_gmt] => 2020-06-29 11:33:38 [post_content] =>
Case scenarioLachlan, a 28-year old man with type 1 diabetes, presents to the pharmacy to speak with a pharmacist. He has a headache, sore throat, dry cough, fever (39.5 °C) and muscle pain. The symptoms started 20 hours ago. Lachlan was anticipating getting the flu vaccine. However, he said he had not got around to it yet. As a young father, Lachlan is particularly concerned about spreading the viral infection to his family. He asks if it is too late to have the influenza vaccine.
Learning objectivesAfter successful completion of this CPD activity, pharmacists should be able to:
Influenza or ‘the flu’ is generally a self-limiting acute viral illness. However, it can also be severe and fatal. In 2019, there were 308,847 laboratory confirmed cases of influenza in Australia.1 Many more cases went unconfirmed. A total of 3,915 individuals were hospitalised and 812 died from influenza.1 The World Health Organization (WHO) estimates globally, that annual epidemics of influenza cause approximately 1 billion infections, 3–5 million severe infections and between 290,000 and 650,000 deaths.2 Prevention and control of suspected and diagnosed influenza are key to reducing its disease burden.
Influenza is an acute, highly contagious, viral infection of the upper (and sometimes lower) respiratory tract that affects individuals of all ages and backgrounds. It is primarily spread by large respiratory droplets (>5 microns) and aerosols, produced when an infected individual coughs, sneezes or talks, that are subsequently inhaled by others. It can also be spread by self-contamination through hand-to-nose, hand-to-eye, hand-to-mouth transmission after touching virus-laden fomites (door handles, toys) or the skin or hands of another person.
It has an average incubation period of between 0.5 and 2 days. Signs and symptoms present abruptly and may include fever (≥37.8 °C)/chills, sore throat, non-productive cough, malaise, headache, myalgia, arthralgia and loss of appetite.3 Some individuals will experience nasal rhinitis and sneezing. Most individuals have symptom resolution within 3–7 days of onset, although a dry cough and/or general malaise may continue for up to 2 weeks.
There are many overlapping symptoms between the common cold, influenza and COVID-19. Table 1 (previous page) outlines the similarities and differences between the three.
Complications of influenza include primary viral and secondary bacterial pneumonia, bacterial coinfection, myocarditis, myelitis, pericarditis, croup, bronchitis, myositis, sinus infection, otitis media, encephalopathy, encephalitis, Reye’s syndrome and death.4 Influenza can also exacerbate existing chronic disease (e.g. asthma, COPD, diabetes, congestive heart failure). Complications of influenza are more frequently seen in individuals who are immunosuppressed, have a chronic disease, residents of aged care facilities, Indigenous, elderly, very young, pregnant, or morbidly obese.5 See Table 2.
Influenza viruses are single stranded RNA-containing viruses that belong to the family Orthomyxoviridae. There are three types of influenza virus that infect humans – types A, B, C. Influenza A and B are by far the most common and responsible for seasonal epidemics. From January through to October 2019, the World Health Organization Collaborating Centre for Reference and Research on Influenza (WHOCC) isolated and characterised 3,949 influenza viruses globally.1 Of this, 88% were influenza A: 60% influenza A, (H3N2) and 28% influenza A (H1N1)pdm09 and 12% were influenza B (11% influenza B Victoria lineage, 1% influenza B Yamagata lineage). During the same time period in Australia, 76.9% of laboratory confirmed influenza cases were influenza A and 22.8% were influenza B.1 While influenza B is responsible for a considerable number of hospital admissions and can be life-threatening, it is not known to cause pandemics. In terms of genetic and antigenic properties, influenza B viruses generally change more slowly (see antigenic drift and shift below).
When viewing influenza A and B viruses via an electron microscope, they are nearly indistinguishable. In both A and B the virus particle (virion) has a spherical or filamentous shape and the virus genome is made up of eight negative single-stranded RNA segments. Once enclosed in a host cell-derived lipid membrane, influenza A and B are studded with haemagglutinin (HA) and neuraminidase (NA) surface proteins.6
Haemagglutinin enables the virus to bind to the sialic acid (SA) receptor on host cells. Once bound, the virus can penetrate inside the host cell by membrane fusion and subsequently become infected. To be virulent, the virus must leave the infected host cell and go on to infect another cell. To do this, the neuraminidase enzyme acts to cleave (or cut) sialic acid from the haemagglutinin molecule attached to the surface of the influenza virus, thereby assisting release of the virus from the host cell. The neuraminidase enzyme is the target for neuraminidase inhibitors (antiviral drugs), including oseltamivir and zanamivir.7
Influenza A, but not influenza B, has matrix (M2) ion channels that traverse the membrane. Inside the lipid membrane, encoded by the virion, are three viral RNA polymerase subunits (PA and PB1, PB2) and the nucleoprotein (NP).
Influenza A viruses can infect a range of mammalian (including human) and avian species. Influenza B virus is categorised based on lineage and spreads almost exclusively in humans (and seals).8
Influenza viruses have a standard nomenclature, i.e. there is an internationally accepted convention for naming influenza viruses.9
Naming involves the:
People at high risk for developing serious influenza-related complications
Other people at high risk from influenza:
Additional details are provided in online edition of The Australian Immunisation Handbook. immunisationhandbook.health.gov.au (refer to Additional resources for primary medical care/vaccination providers).30
Influenza viruses change in two notable ways, antigenic drift and antigenic shift. Antigenic drift is a gradual process which occurs in all influenza viruses and is due to frequent point mutations when the RNA virus replicates. Eventually the mutations accumulate in multiple antigenic sites (e.g. HA or NA) and the virus is no longer recognisable to antibodies that were generated to the parental virus. Without the protection from the antibodies the host once again becomes susceptible to infection by the ‘drifted’ influenza strain. Influenza B viruses change via the more gradual process of antigenic drift; they are not known to cause pandemics.6
In contrast, antigenic shift occurs in influenza A viruses only when there is a major change in the H or N surface protein. It may be a result of genetic reassortment (when influenza viruses swap gene segments). This genetic reassortment can occur when one host (e.g. a pig) is infected with two different influenza viruses. The mixing of the viruses may encode completely novel antigenic proteins (HA and/or NA), to which the human population has no immunity. A pandemic occurs when there is a novel influenza virus (no existing immunity), which can be transmitted in immunologically naive humans. There have been seven antigenic shifts (reassortments) in influenza A virus since 1899 causing five pandemics.9 Pandemics can cause widespread morbidity and mortality across international borders. Influenza pandemics have resulted in millions of influenza-related deaths. The influenza pandemic of 1918, also known as the ‘Spanish flu’, was responsible for approximately 50 million deaths globally.9 The biology and history of influenza A viruses informs us that future pandemics are unavoidable.
Vaccination remains the best protection against influenza. Nationally, pharmacists play a critical role in increasing vaccination uptake and administering vaccinations, particularly in healthy young and middle-aged adults.10 Influenza viruses are rapidly and continuously evolving. This is the rationale behind changing the influenza vaccine composition each year. Vaccination is indicated annually for all individuals aged >6 months.
To provide the greatest protection, seasonal vaccinations should contain viruses that ‘match’ or are antigenically like those currently circulating. Vaccine efficacy is yet to be determined for last year’s influenza season. It will be calculated through observational studies (cohort and case control studies). However, preliminary 2019 data comparing 1,502 circulating influenza viruses to the corresponding vaccine component revealed ‘good’ vaccine effectiveness. Noting that influenza vaccine effectiveness is usually between 30–60%.11
Influenza is easily spread, mainly through respiratory droplets and aerosols, produced when infected individuals sneeze, cough or talk. The virus can also be spread by fomites (any surface that the virus has landed on) that is then touched and passed from the hands to the nose, mouth or eyes. One small study (N =26) showed that on average individuals touch their face 23 times per hour.12 One way of reducing risk of influenza infection and transmission is by thorough hand hygiene.13 Studies show that routine hand hygiene with either soap and running water or alcohol-based hand rubs (ABHR) are effective at removing influenza virus from hands.14,15 Pharmacists should counsel individuals on the importance of regular hand washing with soap and water for at least 20 seconds. When soap and water are not readily available, and hands are not visibly soiled, individuals should be advised to use a hand sanitiser (containing between 60% and 80% v/v ethanol or equivalent) to prevent influenza transmission. Alcohol-based hand rubs should cover the hands thoroughly and cleaning should take 20–30 seconds. More information can be found online at Hand Hygiene Australia at www.hha.org.au
Pharmacists should advise unwell individuals to cover coughs and sneezes, and cough into their elbow. They should also be informed to dispose of used tissues appropriately.
Social distancing measures reduce influenza transmission.16 At a public health level, social distancing strategies that may be employed in an influenza pandemic include school and work closure, working from home, voluntary isolation of cases, quarantine of contacts and cancellation of mass gatherings.
A single use face mask (or surgical mask, face shield) is a loose fitting, disposable face mask that provides a protective barrier around the wearer’s nose and mouth. They are primarily designed to trap respiratory droplets from the wearer and in theory should reduce transmission of infectious microorganisms to others. Several case-control studies identified that wearing masks reduce the incidence of respiratory viruses (OR 0.32, 0.25 to 0.40; NNT = 6, 4.54 to 8.03).17 While a systematic review states that there is little robust evidence to support the effectiveness of face masks to prevent transmission of influenza virus in the natural setting.18
Disposable respirators (e.g. P2, N95) are designed to protect the wearer from infectious aerosols. Respirators can filter out approximately 94% of particles <5 microns in size. Case-control studies have identified they reduce the risk of incidence of respiratory viruses (OR 0.09, 0.03 to 0.30; NNT = 3, 2.37 to 4.06).17
Pharmacists should advise patients to change the mask when it becomes moist, to wash their hands if they touch or dispose of a used mask and to maintain proper hand hygiene.
To date, in Australia, there are three classes of antivirals available for the treatment and prevention of influenza; the M2 ion channel inhibitors, the neuraminidase inhibitors (NAI) and a new antiviral, polymerase inhibitor, which was trialled in several Australian hospitals in 2019.
M2 ion channel inhibitors (e.g. amantadine) prevent the release of viral RNA into the host cell, by targeting viral uncoating. While M2 inhibitors have recognised antiviral activity against influenza A, greater than 95% of the isolated H1N1 and H3N2 influenza viruses are now resistant. Appropriately, this class of medicines is not currently indicated for the treatment or prevention of influenza due to high resistance which has rendered them ineffective.19
Neuraminidase inhibitors (NAI), oseltamivir (Tamiflu) and zanamivir (Relenza), are used clinically worldwide including in Australia. Both work by inhibiting the influenza virus surface protein enzyme neuraminidase (NA). Neuraminidase is a virulent factor and facilitates the release of the influenza virus from the host cell, enabling the influenza virus to go on and infect other healthy host cells. Inhibiting NA reduces the release of the recently formed virus particles from infected cells. Observational studies that included people at high risk of influenza or mortality from influenza, showed that treatment with a NAI is associated with a reduction in influenza complications, hospital admissions and deaths. However, studies of healthy, low-risk adults did not identify a risk reduction in hospitalisation or death (HR 1.03 95% CI 0.64 to 1.65).20 Studies report treatment with a NAI reduces the duration of influenza symptoms by approximately 1 day; oseltamivir 16.8 hours (95% CI 8.4 to 25.1 hrs); zanamivir 0.6 days (95% CI 0.39 to 0.81 days).20 The earlier treatment starts after symptom onset, the shorter and less severe the influenza. Common adverse effects of NAIs include nausea, vomiting and headaches.21
Oseltamivir is administered orally, and is commercially available in both capsules (30 mg, 45 mg, 75mg) and an oral liquid (6 mg/ml). For the treatment of influenza in adults and children 13 years and older, oseltamivir should be given at a dose of 75 mg twice daily for 5 days.21 Treatment is most effective when commenced within 48 hours of symptom onset. Dose reduction is required in individuals with renal impairment. Dosing in children under 13 years is according to total body weight.
For prevention of influenza (e.g. when a household contact has influenza and the individual wants to reduce their risk of getting ill), oseltamivir should be dosed within 2 days of exposure. Adults and those 13 years and over should take 75 mg once daily for 10 days. Children between 1 to 13 years are dosed according to total body weight. In the event of a community outbreak oseltamivir may be taken once daily for 6 weeks.20,22
Case scenario continued
Lachlan has suspected influenza. COVID-19 has been excluded. Individuals with diabetes (type 1, type 2, or gestational), are at high risk of influenza complications, which can result in hospitalisation and even death.
You refer Lachlan to his general practitioner as he will likely benefit from an antiviral. You counsel Lachlan to get rest (stay at home away from work and public places), drink lots of water, to take paracetamol to reduce his fever and relieve his headache and muscle pain.
To reduce spread, you point out the importance of hand hygiene, respiratory/cough etiquette and encourage the use of a face mask. Commencement of antiviral therapy is most effective when commenced early.
As there are many strains of influenza and individuals can catch the flu more than once in a season, you advise Lachlan to get the flu vaccine when he has recovered.
Zanamavir is administered via oral inhalation only. It is available commercially as a dry powder inhaler (DPI), which contains 5 mg of zanamivir inhalation powder in each pre-dispensed blister. For the treatment of influenza, within 48 hours of symptom onset, adults and children 5 years and over should inhale 2 blisters (10 mg), twice daily (approximately 12 hours apart) each day for 5 days.21 When prevention is required treatment should commence within 36 hours of exposure, and two blisters should be inhaled once daily for 10 days. Prevention can be extended up to 28 days when required (e.g. during a community outbreak).
Poor inhaler technique, results in inadequate drug delivery and therapeutic failure. Pharmacists should provide appropriate counselling (including device demonstration) on how to administer and use the DPI for all individuals prescribed zanamivir. Individuals who take a bronchodilator at the same time as zanamivir, should use the bronchodilator first, followed by the antiviral. During pregnancy zanamivir is the preferred NAI due to its low systemic bioavailability.21
Recent surveillance data has identified that oseltamivir-resistant viruses are circulating.23 Of concern, is that drug-resistant virus strains can spread to contacts. Resistance to neuraminidase inhibitors, is of concern at the public health level, as they are stockpiled and used in the prevention and treatment of pandemics.24
Baloxavir marboxil (trade name Xofluza) is a new influenza antiviral with a novel mechanism of action, that is effective at reducing the severity of both influenza A and B.25
Each influenza virus contains three polymerase subunits (PA, P1 and P2). The subunits are responsible for the replication and transcription of viral mRNA genome.26 Baloxavir targets, binds and inhibits the endonuclease function of the viral PA polymerase subunit. Binding prevents the transcription of viral mRNA and subsequent replication of the virus in the host cell. Baloxavir marboxil offers a novel