Archive for the ‘Influenza viruses’ Category
New Approaches to Vaccines for Human and Veterinary Tropical Diseases. Or maybe sophisticated safari science?27 May, 2016
The Keystone Symposia organisation held a meeting entitled “New Approaches to Vaccines for Human and Veterinary Tropical Diseases” in Cape Town this week (May 22-26, 2016). A summary of the meeting was given as:
“Human and livestock vaccines can contribute to improved human welfare and income generation by maintaining human health and meeting the demand for meat, milk and fish in developing countries. All of these factors contribute to the growing importance of improving food safety, availability and nutritional security. An important component of this Keystone Symposia meeting will be to stimulate crosstalk between the human and veterinary vaccine communities by highlighting cross-cutting technical advances and new science and knowledge from laboratory and field research. The meeting will also provide a rare opportunity for scientists from the Northern and Southern hemispheres to interact and pool resources and knowledge in the common fight against tropical diseases.”
It succeeded admirably in a couple of these goals: there were delegates there from 31 African countries, as well as many Europeans, Brits and Americans; the juxtaposition of veterinary and medical talks on similar themes created an excited buzz among folk who hadn’t been exposed to the “other”; there was a wealth of dazzling new tech on display in talks, and intriguing insights into how similar – and sometimes, how different – human and animal responses to vaccines were. It was obvious that approaches used to develop malaria vaccines could benefit animal vaccinology, and indeed, Vish Nene and colleagues from ILRI in Kenya are following some of the same approaches in their work with the East Coast fever disease organism in cattle.
But, there were a couple of buts. An important one for me was that while there were many Africans there, they were not much exposed in talks, apart from several South Africans. While amazing results were displayed from deep sequencing of antibody gene repertoires of humans and animals and how these developed with affinity maturation; while grand predictions were made as to how bioinformatics and molecular design would revolutionise vaccinology – this was more of the same kind of thing we have got used to in HIV vaccine meetings over nearly twenty years, where Big Science is always going to provide a solution, but never quite gets to it. Why was there no mention of ZMapp antibody therapy for Ebola, when this (OK, I’m biased) was the single most exciting thing to come out of the Ebola outbreak and the international response to it?
I hate to be cynical, but seriously: is there one single vaccine in advanced human trial right now that is a result of intelligent molecular design? Has ANYTHING that has been designed from crystallographic evidence or from cryoEM data actually proven useful in animals or people? Has dissection of the anti-HIV antibody response development actually, really, taught us anything useful about how we should develop vaccines? Even if South Africans were involved?
I told you I was cynical – and my cynicism was reinforced by a couple of displays of “My Ebola vaccine is better than YOUR Ebola vaccine!”, by folk who shall remain nameless – when it was obvious that both ChAdOx and rVSV vaccines have their merits.
Mind you, the tale of how Ebola vaccines were deployed so rapidly, and how what could have been a 15+ year saga was compressed to less than a year for the rVSV-ZEBOV and ChAdOx vaccines was truly inspirational. It is indeed an object lesson in how to respond to an emerging disease that big companies and philanthropic organisations were able to make many thousand doses of different vaccine candidates in just a few months, and that these could be deployed in human “trials” – actually, genuine deployment in ring vaccination for the VSV candidate – almost immediately. Adrian Hill of Oxford asked the question, albeit outside the meeting at a seminar in our Institute: if this was possible for an Ebola outbreak, why isn’t it possible for everything else? Why can’t we do it for Zika virus, and for MERS-CoV too?
If there is a Big Lesson to come out of this meeting, why can’t it be – Let’s Make Vaccines Faster!
Oh, there were big plusses too. There were fascinating parallels to be drawn in the approaches to developing vaccines for malaria and TB and animal parasitic infections; some of the fancier techniques discussed for human vaccines could obviously find applications in veterinary vaccinology; there were even suggestions for vaccine candidates for animals that were drawn from homologous genes in human and animal apicomplexans (=malaria-like organisms).
I was especially impressed by Dean Everett‘s talk, from the Malawi-Liverpool-Wellcome Trust Clinical Research Programme in Malawi, on “Developing Appropriate Vaccines through Bioinformatics in Africa”: they were actually working in under-developed Africa, on pressing local problems, and making significant inroads into the problems.
And yet, and yet: I have railed elsewhere about the J Craig Venter Institute’s grandstanding over their “synthetic” organisms; while the talk here by Sanjay Vashee on “Synthetic Bacterial and Viral Backbones as Antigen Delivery Vehicle” went some way to redeeming my negative impression of the use of this sort of work, I am still left with the impression that there are considerably easier ways of doing what they claim to be able to. Mind you, one of my colleagues was very impressed with the possibility of making Herpesmids (=infectious, engineerable whole genome clones) in yeast, and would love to do it with their poxvirus collection – so maybe I am a touch TOO too cynical.
I also felt that the final address, by Chris Wilson of the Bill & Melinda Gates Foundation, on: “Cross-Disciplinary Science to Accelerate the Discovery of Vaccines for Global, Zoonotic and Emerging Infectious Diseases” exemplified some of the problems inherent in trying to marry up developed and developing world science, especially in vaccinology. Part of the talk was great: he gave the best description I’ve yet heard of why it could be feasible to inoculate Aedes spp. with Wolbachia, and why it could significantly impact transmission of flavi- and other viruses. His description of gene drive technology for wiping out selected mosquito populations was also succinct, and masterly – and appropriate for a developing world audience. Then he got on to how dissection of antibody maturation pathways and flavivirus E protein design could provide paths to good vaccines, and the cynicism kicked in again.
We don’t need either technology to get to vaccines for HIV or for flaviviruses that we can test in the near future, and which could have very significant impacts on millions of people.
Really: we don’t. Extant HIV vaccine candidates are almost certainly better than the RV144 Thai trial vaccine components, and they had an efficacy of 60% in the first year. We already have YFV and dengue and JEV live vaccines – why don’t we use one or several of them in combination with an engineered YFV vaccine to protect against ALL epidemic flaviviruses? Given the Ebola example, we could deploy vaccines for HIV and for flaviviruses in a year or less, and they would have an impact that would tide us over while fancier products were being made. Seriously: we are always waiting for the next best thing; let’s just apply what we know and what we have NOW to make an impact – instead of, like theoretical physicists, perpetually considering the problem of the spherical horse instead of just going out and riding one.
And that should have been one of the Big Lessons, and we missed it. Instead, there was an element of Safari Science, which is what we in Africa call the kind of endeavour which involves people from the global North flying in to sort out our problems – and leaving with our organisms and disease samples.
Which we could do ourselves, given funding. And that’s another lesson for the folk that do Big Science funding….
The means of engineering potentially deadly avian influenza is freely available on the internet.
Despite continuing global efforts to contain avian influenza, or bird flu, the means of engineering this potentially deadly H5N1 virus to render it transmissible to humans is freely available on the internet. So too are similar instructions for engineering a virus like the “Spanish flu”, which killed some 50 million people in the pandemic of 1918-19.
The digital floodgates opened in 2011 when a peak US regulatory watchdog came down in favour of scientists seeking to publishing their work engineering the H5N1 virus. The decision to uphold such “scientific freedom” was and remains, highly contentious among the global scientific community. Its implications, however, are readily available as online “recipes” for potentially dangerous viruses, which add a new risk to the already considerable challenges of maintaining global biosecurity in the 21st century. For all the recent advances in biomedical science, drugs, vaccines and technology, this is a challenge we remain ill-equipped to meet.
Read more: http://www.theage.com.au/comment/online-recipes-for-contagious-diseases-means-australias-bioterrorism-threat-is-real-20151208-gli97v.html#ixzz3tvWn63AE ;
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Sourced through Scoop.it from: www.theage.com.au
OFFS: seriously! Again?! Someone else has just discovered that entire virus genomes are freely available via PubMed, along with papers on gain-of-function experiments, and immediately leaps to the conclusion that this means “…the means of engineering this potentially deadly H5N1 virus to render it transmissible to humans is freely available on the internet”.
I’m sorry, this is being simple-minded to the point of parody. I have written elsewhere – here in ViroBlogy, and in Nature Biotech’s Bioentrepreneur blog section – on how it is MOST unlikely that bearded fellows in caves in Afghanistan or remote farms in Montana are going to whip up weaponised batches of H5N1 flu or Ebola.
Yes, the papers are available; yes, the sequences necessary to make a potentially (and I say potentially advisedly) deadly virus are available online; yes, one can bypass the blocks on getting resynthesised genes in developing countries (hint: China).
But could anyone outside of a sophisticated lab environment use these to make anything nasty?
Just think about what you would need to make weaponised flu, for example. There are two ways to go here, these being the totally synthetic route (“mail order” DNA – HATE that term!), with some serious molecular biology and cell culture at the end of it, and the “natural” route – which would involve getting a natural and nasty isolate of H5N1 / H7N9 / H9N2, and being able to culture it and engineer it as well.
Both routes require a minimum of a serious 4-yr-degree-level training in microbiology / mol biol, as well as laboratory resources that would include incubators, biohazard cabinets, and disposables and reagents that are not on your normal terrorist’s priority purchase list.
In fact, the kinds of resources you’d find at a University or Institute Infectious Disease unit – or state-sponsored biowarfare lab.
Seriously, now: in order to use the information that is “freely available”, you’d have to do what amounts to an entire postgrad degree’s worth of work just to set up the kinds of reverse genetics necessary to WORK with recombinant flu, presuming you already had an isolate, and even more than that if you were to start with synthesised DNA and try to recreate infectious virus.
Again, this is the kind of work they do in biowarfare / biodefence labs (funny how they’re pretty much the same thing, isn’t it?) – because it’s finicky, expensive, laborious – and potentially dangerous to the researcher.
And it’s interesting that the only rumoured escapes of biowarfare agents have been of flu in 1977 in the old Soviet Union, and of anthrax in Sverdlovsk in the USSR in 1979. And in the US in 2001, and again in 2014. ALL of them from official facilities, I will discreetly point out.
Oh, there have been rumours that Saddam’s Iraq weaponised camelpox; that the USSR/Russia cloned Ebola into a poxvirus; that Al-Qaeda tested anthrax – but the first two took state resources, and if the third happened at all, it’s nothing that the UK and USA and friends hadn’t already done in the 1940s.
IT IS NOT THAT EASY TO MAKE RECOMBINANT VIRUSES.
Like my recent books on History of Viruses and Influenza, I’m constructing an ebook Introduction to Virology textbook – and I’d like people’s opinions.
It’s going to look something like this:
It will be based on my web pages that were so cruelly destroyed, but will be PROFUSELY illustrated, using all of the bells and whistles built into the iBooks Author app, with liberal use of Russell Kightley’s very excellent virus picture library.
And I will sell it for US$20 or less.
Tell me what you think of the taster – and there will be more.
REGISTRATION IS NOW OPEN – VIROLOGY AFRICA 2015
On behalf of the Institute of Infectious Disease and Molecular Medicine of the University of Cape Town and the Poliomyelitis Research Foundation, we are pleased to invite you to Virology Africa 2015 at the Cape Town Waterfront.
VENUE AND DATES:
The conference will run from Tuesday 1st – Thursday 3rd December 2015. The conference venue is the Radisson Blu Hotel with a magnificent view of the ocean. The hotel school next door will host the cocktail party on the Monday night 30th November and in keeping with Virology Africa tradition, the dinner venue is the Two Oceans Aquarium.
Early Bird Registration closes – 30 September 2015
Abstract Submissions deadline – 30 September 2015
The ACADEMIC PROGRAMME will include plenary-type presentations from internationally recognised speakers. We wish to emphasise that this is intended as a general virology conference – which means we will welcome plant, human, animal and bacterial virology contributions. The venue will allow for parallel workshops of oral presentations. There will also be poster sessions. Senior students will be encouraged to present their research. We have sponsorship for students to attend the meeting and details will be announced later in the year.
A program outline has been added to the website
Our preliminary programme includes two workshops.
There is a hands-on workshop on “Plant cell packs for transient expression: Innovating the field of molecular biopharming”, with the contact person being Dr Inga Hitzeroth – Inga.Hitzeroth@uct.ac.za. This workshop will run at UCT one day before the conference, 30th November, and a second day, 4th December, after the conference.
The second workshop is on “”Viromics for virus discovery and viral community analysis”. The workshop at UCT will be on 4 and 5 December with the contact person being Dr Tracy Meiring – email@example.com.
Some of the workshop presenters will be integrated into the conference programme but the practical components will be run at University of Cape Town. Separate applications are necessary for each workshop.
If you are prepared to fund an internationally recognised scientist to speak at the conference or if you wish to organise a specialist workshop as part of the conference, please contact
Anna-Lise Williamson or Ed Rybicki.
For any enquiries please contact
Miss Bridget Petersen/ Email: firstname.lastname@example.org or phone: +27 21 486 9111
Ms Deborah McTeer/Email: email@example.com or +27 83 457 1975
I would like to test the response to a Introduction to Virology ebook that I want to develop from my extant Web-based material, given that this is likely to disappear soon with our Web renewal project here at UCT.
Download the Virus Picture Book excerpt here. And then please tell me what you think / whether you would buy one (projected price US$15 – 20)? Ta!
This is excerpted from the ebook “Influenza Virus. Introduction to a Killer”, which is available here for US$9.99 .
Influenza: the disease
Influenza: a disease and a virus
Influenza as a disease in humans has been known for centuries; however, its cause was only discovered in the early 20th century: this was the group of viruses now known as Influenza virus types A, B and C.
There are several influenza viruses circulating in humans at any one time; these cause “seasonal flu”, which is usually a mild disease because most people have some degree of immunity.
Influenza pandemics, however, are caused by novel viruses – which are generally derived from animals, and usually originate in birds. Here, the disease can be much more severe.
Influenza viruses have caused some of the biggest and yet some of the most insidious disease outbreaks to have hit humankind: from 1918 to 1920, the “Spanish Flu” pandemic killed more than 60 million people across the world; subsequent pandemics in 1957, 1968 and 1977 killed millions more, and the count is still unclear on the 2009 pandemic. However, in any given year more than 400 000 people probably die of so-called “seasonal flu” – yet universal vaccination against it is still a dream.
What is Influenza?
What is Influenza?
The Centers for Disease Control and Prevention in the USA define influenza as
“…a contagious respiratory illness caused by influenza viruses that infect the nose, throat, and lungs. It can cause mild to severe illness, and at times can lead to death.”
The disease is transmitted mainly via droplets of respiratory secretions: these result from sneezing or coughing, which blows out a fine cloud of droplets or aerosol from the upper airways of infected people. Breathing in or inhalation of these droplets – which can happen from 2 metres away – or transfer of droplets by hand from a contaminated surface to the mouth, is enough to cause infection.
The virus initially infects cells of the upper airway, or the respiratory epithelium. Spread to lower parts of the respiratory system, such as into the lung, depends upon the particular virus, and whether or not the individual is partially immune.
- Fever or chills
- Sore throat
- Rhinitis, or runny nose
- Muscle or body aches, headaches
- Tiredness, “fuzzy head”
- Vomiting and/or diarrhoea (more common in children than adults).
The average incubation period, or time from infection to disease, is about 48 hours. Full recovery can take a month, although about two weeks is more common in seasonal flu. People can pass on the virus before they show symptoms, and each infected person on average infects another 1.4 people.
While flu may be mild enough that it is hardly noticed, severe disease can also occur – especially in the elderly, the very young, heavy smokers, people who are chronically ill from other causes – and immunocompromised individuals.
While the virus can cause pneumonia directly due to damaging lung tissue, as happened in the “Spanish Flu” pandemic, severe illness with pneumonia is more usually due to secondary bacterial infections – which can be treated with antibiotics, unlike the viral pneumonia.
Seasonal flu, or the disease caused by viruses circulating in the population, typically has an “attack rate” of between 5-15% of the population in annual epidemics. Case fatality rates, or deaths among those infected, are usually between 0.1 – 0.3%. However, pandemic flu – caused by new strains which arise spontaneously, and to which people are not immune – can attack from 25-50%, and kill 5% of those infected. Seasonal flu also mainly infects children – because older people are often immune – but mainly causes severe disease and death in the elderly: up to 90% of victims are usually 65 or older.
Conversely, pandemic strains may affect a different set of age groups: for example, the Spanish Flu affected mainly healthy young adults.
Seasonal influenza is typically a disease of the autumn and winter seasons in temperate zones – meaning October – March in the northern hemisphere, and April – August in the southern. The CDC FluView graph shown here clearly illustrates the cyclical nature of seasonal flu, tracked in the USA over a 5 year period. However, the exact timing is not reliable, and epidemics may peak as early as October in the north, or April in the south, or as late as the end of the season.
here the virus may circulate year-round, typically with a peak during the one or two rainy seasons. Because of demographic reasons incidence is severely under-reported: however, in a seasonal outbreak in Madagascar in 2002, there were more than 27 000 cases reported in 3 months, with over 800 deaths for a case-fatality rate of around 3%. A WHO coordinated investigation of this outbreak found that there were severe health consequences in poorly nourished populations with limited access to adequate health care.
Why is influenza seasonal?
Many reasons have been invoked over the years to explain this, ranging from temperature, humidity, school schedules, increased indoor crowding during winter or rainy seasons, and even variations in host immunity due to lack of vitamin D or melatonin. However, the same reasons cannot be given for both the increase in influenza incidence in temperate climates with the onset of winter, and the rainy season peaks in tropical regions, given the very different environmental conditions prevailing.
A recent study set out to systematically determine the interactions between relative humidity, and salt and mucus and protein content of droplets containing live flu virus, on the viability of the virus – and came up with conclusions that could explain the temperate / tropical transmission differences.
Essentially, their explanation for temperate region seasonality is that there is low relative humidity indoors in winter due to heating: this leads to increased survival of virus due to drying of particles – influenza A viruses are stabilised by being dried in the presence of salts, mucus and proteins – and leads to aerosols persisting longer in the interior environment due to smaller size, and being propagated further, meaning most transmission would be by this route. Increased time spent indoors and increased indoor crowding due to the climate would obviously increase transmission rates under these conditions.
Tropical environments present a very different picture: here, high temperatures would accelerate virion decay, which would tend to decrease any transmission. However, in rainy seasons, temperatures drop and relative humidity increases to nearly 100% – conditions conducive to survival of large drops, which settle out quickly onto surfaces, where the virus remains viable. Thus, transmission could be mainly by surface contact. The same social factors apply as for temperate climates, with frequent rain leading to more time indoors and more crowding – and a greater opportunity for transmission.
Flu vaccines can be something of a shot in the dark. Not only must they be given yearly, there’s no guarantee the strains against which they protect will be the ones circulating once the season arrives. New research by Rockefeller University scientists and their colleagues suggests it may be possible to harness a previously unknown mechanism within the immune system to create more effective and efficient vaccines against this ever-mutating virus.
Sourced through Scoop.it from: www.news-medical.net
So: antibody-antigen complexes work better than antigen alone – and sialylation of the antibody is important. Vaccinology really is entering the 21st century!
I have to thank my long-time digital media guru, Alan J Cann, for reviewing our humble eBook offerings in MicrobiologyBytes. You good man! Much appreciated, and it will not have escaped our attention that this endorsement may actually result in sales. If so, a glass or three of the finest red is yours if you come to these shores, good sir B-)
For some five years now, I have been simultaneously writing two ebooks on viruses. The one – originally part of a longer effort not yet finished – is “A Short History of the Discovery of Viruses” which is also advertised on Virology News; the other is a labour of love on influenza.
Labour of love for me because I got more into it the more I read, and because Russell Kightley’s images were so amazing.
Both were written using Apple’s iBooks Author app; both are designed to be read by Apple’s iBooks app on iPad, iPhone or Mac.
So here it is: