The piece ‘Mosquitoes shoot blanks in scientist’s air war on Dengue‘, by Andrea Gerlin looks at the increasing threat posed by the rising worldwide incidence of Dengue fever, and how Oxitec’s approach could provide a solution.

View the full article here

Continuing the fight against the dengue mosquito in Brazil

Critical to Oxitec’s approach to pest control is the ability to consistently rear large volumes of high quality insects, and this has been the case with our work in Brazil against the dengue vector mosquito, Aedes aegypti. In a partnership between Oxitec, Moscamed and the University of Sao Paolo, transfer of Ae. aegypti mass-rearing protocols from the UK to a newly established laboratory in Brazil has been successfully achieved over the past year. This involved establishment of local infrastructure: laboratory construction, hiring and training the local team, transfer of methodologies and optimising production locally. For consistency and reproducibility it is important to maintain production methods as close as possible to those developed by Oxitec. However, many of the materials and equipment available in UK are not available in Brazil, and have been substituted with locally sourced counterparts. Rearing and release procedures have therefore been adapted optimized accordingly, with resulting improvements in numbers produced, consistency and quality. This has been an ongoing process, with communication between Oxitec UK and Brazilian collaborators critical to success. Key to this has been the web-based data handling system that enables Brazilian and UK Oxitec to easily share and assess data from their respective labs. A testimony of the success of technology transfer and the local optimisation has been the increase in egg production from around 1 million eggs/week to over 4 million/week. In parallel, adult male production has increased from less than 50,000 to the current rate of over 500,000 males/week. We believe current production is close to the maximum capacity for the insect rearing unit. Construction is therefore underway of a substantially larger rearing unit nearby that should be able to produce far more adults per week, and will allow larger-scale control operations to take place against this mosquito. Meanwhile, field releases of male Oxitec mosquitoes are yielding promising results, which we will report in more detail in the near future.

Some of the team in Brazil hard at work in the mosquito production unit

‘Claymation’ mosquitoes star on Oxitec’s re-vamped website

Better communication begins at home, and as part of Oxitec’s outreach and communications effort, we’ve launched new company branding and a new website this week.

The aim was to offer visitors to our site a clearer, more user-friendly interface, where they can quickly find the information they need. The new site is now up and running at www.oxitec.com

Alongside our new site, we’ve also launched an educational film, ‘Controlling the Dengue Mosquito – the Oxitec Solution’. The film, which uses clay animation, or ‘claymation’, is intended to improve the clarity, accessibility and transparency of Oxitec’s work and research.

Dr Paul Reiter, Professor of Medical Entomology at the Pasteur Institute, who features in the film, said that the scientific community “doesn’t always do a good job addressing the many questions asked of it” and that failing to communicate effectively “can lead to unease about a new approach.”

In addressing real concerns that new technologies are not well understood, Oxitec was “inspired to think more creatively about how we communicate and engage people with complex science, which is why we chose clay animation,” said Hadyn Parry, Oxitec CEO. “This way everyone is given the opportunity to understand and evaluate what we do.”

Haedes and Aegypta, stars of the new film

Panama’s Gorgas Institute prepares to evaluate Oxitec’s mosquitoes

Participants in the Forum ‘Transgenic Mosquitoes: A new tool for the control of Aedes aegypti in Panama’. From left to right: Marco Neira (researcher, Oxitec), Lorenzo Cáceres (researcher, ICGHS), Vicente Bayard (researcher, ICGHS), Néstor Sosa (Director, ICGHS), Franklin Vergara (Health Minister, Panama), José San Martin (Dengue expert, Pan-American Health Organization).

In recent years, Panama has suffered the effects of a marked increase in the incidence and severity of dengue fever cases. In an effort to explore innovative and effective approaches to counter this worrying trend, in 2011 Panama’s Gorgas Commemorative Institute for Health Studies (GCIHS) teamed up with Oxitec to evaluate the use of Oxitec’s RIDL strains for controlling local populations of Aedes aegypti, the dengue-transmitting mosquito.

In preparation for laboratory and field trials, the GCIHS and Oxitec have taken important steps towards obtaining the regulatory clearance for the project, as well as building the human and physical infrastructure required by an enterprise of this magnitude.

The priority for such a trial has been to submit permit applications and follow the required regulatory assessment. Under Panamanian law, all work involving genetically modified mosquitoes must be approved and regulated by several entities, such as the National Biosafety Commission and the Panamanian Committee for Health Biosafety.

In terms of infrastructure, dedicated insectaries have been built and equipped at the Gorgas Institute for the rearing and preliminary testing of transgenic mosquito strains. Additionally, GCIHS researchers have received specific training at Oxitec’s laboratories in the techniques required for rearing and manipulating RIDL mosquitoes. Potential field sites have been identified in Panama, where the populations of Ae. aegypti mosquitoes are being continuously monitored.

Scientists from the Gorgas Institute and Oxitec have been working hard to keep community members informed about this new technology and its potential applications in Panama. To this effect, the GCIHS organised the forum ‘Transgenic Mosquitoes: A new tool for the control of Aedes aegypti in Panama’, which took place in October 26th, 2011. This event provided a platform for researchers, government officials, international experts and community leaders to come together and discuss the use of transgenic mosquitoes in Panama. In addition, GCIHS and Oxitec researchers have met with the residents of areas affected by dengue fever, providing an opportunity to discuss the project and listen to and address any concerns that the area residents might have.

Both Oxitec and the Gorgas Institute recognise the importance of a well-informed, public debate on this topic, and it is for that reason that we have sought to work not only with scientists and regulatory authorities, but also with members of the media and the public at large. We are convinced that Oxitec’s solution can provide much-needed relief to the Panamanian population affected by dengue fever, and we look forward to applying our technology in the service of those in need.

Lorenzo Cáceres, a researcher from the Gorgas Institute, presents the project to community members

Oxitec’s technology and the environment

Some insecticides may have a negative effect on bumble bee health

Since the impact of the insecticide DDT on biodiversity became clear in the 1960s, the general public has become increasingly active in demanding that disease vector control and food production systems have minimal negative effects on the environment. In an ideal world, pest control efforts would only affect the target organisms so that local ecology remains untouched. With many existing practices, off-target effects and a consequent impact on biodiversity are difficult to avoid. Ecological concerns over chemicals have led to the growth of integrated pest management (IPM), which uses diverse control tools to provide pest control with minimum environmental impact. IPM on one farm might use a combination of, for example, natural predators, pheromone disruption and some pesticide spraying.

Oxitec’s control technology, called ‘RIDL®’, relies on genetically ‘sterile’ male insects mating with wild females so that all of their progeny or just the females do not survive. If enough such males are released, the wild population crashes. As male insects reproduce only with their own species, RIDL is species-specific in action, with consequently minimal off-target effects. Moreover, the method is self-limiting, so the insects are not able to persist in the environment. From an environmental and a regulatory perspective, these are highly attractive qualities for a pest control method.

Pests of agriculture and public health are generally at artificially high numbers due to human activity or, simply, human presence. For example, the dengue vector mosquito Aedes aegypti likely originated in one region in Africa. Through inadvertent transport by man it has only established in other parts of the world in recent years, where it is largely tied to living near human habitations. The Cayman Islands Mosquito Research and Control Unit (MRCU) conducted field trials with Oxitec mosquitoes against local populations of Aedes aegypti in the Caribbean island of Grand Cayman. In advance, we considered the potential consequences of successful knock-down of the wild population. That this mosquito is an alien species on Grand Cayman, present in relatively small numbers, indicates that reduction in its numbers would not disturb a long-term ecological balance in the area. Secondly, several other mosquito species – particularly the black salt marsh mosquito (Aedes taeniorhynchus) – are much more numerous than Aedes aegypti on the island (http://www.cayman.gov.ky). Mosquito predators are therefore much more reliant on other species for food. That control by RIDL is specific to Aedes aegypti only underlines the potential ecological value of such a species-specific approach.

Agricultural pests are commonly at unnaturally high levels due to modern farming practices, which generally involve large-scale cultivation of one crop type in a field. Without control, pest levels can increase unchecked, resulting in loss of the crop. Modern agriculture is increasingly looking to preserve local biodiversity, which can actually be beneficial to the farmer. The presence of natural predators or parasitoids can help to keep pest numbers down. Pollinators can boost fruit yields. Clearly, there is a community of animals that the farmer would not want to reduce, so targeting just the damaging pests is best for all concerned.

Off-target effects of pest control remains a hot topic, with recent studies indicating that bee health is threatened by sub-lethal amounts of certain insecticides (neonicotinoids) in the environment (Whitehorn et al. 2012 Science pp 1555). Meanwhile, IPM expansion depends on the development of new and effective chemical-free tools. RIDL looks set to offer this for a number of important pests in public health and agriculture.

The many native species of mosquito on Grand Cayman breed in swamps that occur naturally on the island (left). Aedes aegypti tends to breed in smaller bodies of water, such as in peoples’ plant pots (right).

Invasive pest insects: an escalating problem

April 2012 has been dedicated as the Invasive Plant Pest and Disease Awareness Month by the US Department of Agriculture, bringing the problem of invasive pests into sharp focus. As international movement of people and goods continues to rise, the risk of inadvertent movement of dangerous pests increases with it. Why do new arrivals pose such a threat? Farmers are generally familiar with control practices that are effective against each of the pests that damage their crops. A new arrival can be an unknown quantity in this regard. Farmers need to find out which of their tools will work best against the invader, and this can take some time. Similarly, natural predators often need time to get to grips with the new pest. Until that does happen, the numbers of the invader may increase to devastating levels.

For this reason, farmers live in fear of certain species finding their way to their crops. As discussed in one of our accompanying articles, most of the major pests around the world are causing a problem beyond their native regions. The tomato pest moth, Tuta absoluta, is a prime and topical example. Native to part of South America, over the past 30 years it has spread across the continent where it continues to cause grower losses. In 2006, it arrived in Europe, possibly carried by ship in plant material. Ever since, it has become the biggest problem for tomato growers in the region and beyond. It has reached the Middle East and North Africa, and its spread – by short-distance flight and longer distance with man (e.g. freight) – through Asia, Africa, Central and North America is looking imminent. Oxitec is currently working to develop a product against this very significant pest.

Another similar story is the red palm weevil (Rhynchophorus ferrugineus), which has spread from its native Asia to the Middle East, North Africa, Southern Europe, and now the Americas. Wherever it finds a home, it devastates commercial palm (e.g. dates and palm oil) and ornamental palm trees. The larvae burrow in the tree, usually resulting in death. Because of the lifestyle of the larvae, they are difficult to reach and no easy way of controlling this pest has yet been established. Insecticide can be injected into the infected tree, but identifying these trees is difficult.

The Asian long-horned beetle (Anoplophora glabripennis) is a similar pest in many ways. Their larvae also kill trees by feeding in the trunk or branches. The UK’s Food and Environment Research Agency have just announced its arrival in the UK, with the result that potential host trees will need to be destroyed in the immediate vicinity. If these initial measures are not successful, the UK Forestry Commission fears that the beetle’s dispersal and establishment could result in the loss of a great many more trees to eradicate it, as seen in Italy and the USA.

For similar reasons, fears about introducing a new species hamper the uptake of biological control (biocontrol) agents, such as predatory mites or parasitic wasps, in many countries. This largely stems from a previous introduction that went badly wrong. The use of the Asian harlequin ladybird (Harmonia axyridis) for control of pest insects on US and European farms ended in the ladybird establishing and spreading throughout the region, outcompeting and displacing native ladybirds. Understandably, regional regulators have since been much more rigorous in their assessments of potential impacts.

Like biocontrol, Oxitec’s RIDL technology is a chemical-free alternative for farmers. Unlike biocontrol, in RIDL the released bug is the same species as its target, and is inherently self-limiting and therefore not able to persist in the wild. From a biosafety perspective, this is a huge advantage. Moreover, one might use RIDL as a protective barrier against an invading pest, releasing RIDL males in anticipation of wild females’ arrival. As it uses the insects’ own mate-seeking behaviour, RIDL works well when pest numbers are low. In contrast, pesticide spraying is rather less good at hitting scarce targets and prophylactic spraying might be difficult to justify. RIDL might, therefore, be seen as the preventative measure of choice for some serious pests.

Adult red palm weevil

Other news

Public meeting in Florida

In March, Oxitec CEO Hadyn Parry and CSO Luke Alphey attended a town-hall meeting in Key West, Florida, organised by the Florida Keys Mosquito Control District (FKMCD). The aim of the meeting was to meet local residents and discuss with them plans to evaluate Oxitec’s mosquitoes in Key West. The event was covered by Miami TV and by UK’s Channel 4 news. The resulting Channel 4 piece presents an interesting and balanced perspective on Oxitec’s approach (http://www.channel4.com/news/florida-frontline-for-new-gm-mosquito-tests).

Brazil mosquito control workshop

Last month also saw the release of early results from the trial of our OX513A mosquitoes in Brazil, which were presented at a workshop of international experts, politicians and regulators by our partner, Moscamed. The Moscamed president, Dr Aldo Malavasi, spoke about the extensive public engagement activities which have been undertaken in Brazil. As part of the first phase of the trial project representatives have visited every house in the trial area, met with local leaders and press, both print and TV, held local community meetings and published leaflets and other information resources. The event has received positive coverage in both local and international media, including Nature Blogs and the international science network SciDevNet.

The workshop in progress

Media coverage

Oxitec’s approach to pest control received positive coverage in the Wall Street Journal by renowned science journalist Matt Ridley (http://online.wsj.com/article/SB10001424052702303815404577335703043691304.html#articleTabs%3Darticle). The article makes a brief reference to Western pressure groups’ tendency to sometimes overlook potential benefits of new technology. Another recent article, printed in Outlooks on Pest Management (Livermore 2012 23(2):62-64), discusses this issue in more detail, with some criticism of a few pressure groups unsophisticated attitude to science-based decision-making. The author writes that “if the activities of NGOs prevent the benefits of technologies such as this from reaching the poor and disadvantaged, they will bear a heavy responsibility.”

Lastly, Mail on Sunday columnist Christian Jennings published a positive article on our technology and its potential to benefit global health (http://www.mailonsunday.co.uk/home/moslive/article-2121584/Mosquito-factory-Can-malaria-stopped-British-bred-genetically-modified-mosquitoes.html).

Read ‘A Genetic Swatter for Deadly Mosquitoes’ here.

Part one

Featuring never-before-seen footage and exclusive interviews with Haedes and Aegypta – representatives of the notorious Dengue mosquito – this film tackles some of the big questions about this dangerous virus, and what Oxitec can do to help.

Part two

In this video, you can learn more about how the Oxitec approach works, and how it is providing what Professor Paul Reiter describes as a ‘cutting-edge’ solution to the growing threat of Dengue fever.

Dengue, Mosquitoes and Genes: an information pack to accompany the Oxitec film

Watched the film? Interested in finding out more? We’ve produced an information pack to accompany the film, which looks at some of the issues it tackles in a bit more detail. Read through it to find out more about Dengue fever, the Aedes aegypti mosquito, and how Oxitec is using genetic technology to tackle a growing problem. You can use the links below or on the left to skip to the content that interests you. More information is also available on our Health pages.

Introducing the information pack

Dengue fever: a growing problem

Introducing Haedes and Aegypta: all about the Aedes aegypti mosquito

Using genes to control insects: the Oxitec solution

More about the science: how does Oxitec make a genetically modified insect?

The project, called ‘Projeto Aedes Transgenico’ (PAT), is the result of collaboration between the University of Sao Paulo, Moscamed and Oxitec and is supported by the State of Bahia government through the Secretary of Health, SESAB and Secretary of Science Technology and Innovation. The trials are being carried out in the Juazeiro area in Bahia state.

The meeting was part of an ongoing process to involve senior government and health officials in the progress of the trials and community engagement. Participants included representatives from the National Dengue Control Programme, Fiocruz, the Secretary of Science and Technology of Bahia state and Secretary of Health of Bahia as well as leading international experts.

Dr Aldo Malavasi, President of Moscamed, said:

“Openness and transparency have been a clear focus of PAT from the outset, and a vigorous and proactive community engagement campaign has been carried out involving all levels of the community.”

As part of the first phase of the trial project representatives visited every house in the trial area, met with local leaders and press, both print and TV, held local community meetings and published leaflets and other information resources. At the meeting Dr Malavasi reported that the response of the local community and wider public had been “very encouraging.”

Dr Margareth Capurro of the University of Sao Paulo, who is leading the project, said

“The latest results are very positive. We have used this data to plan two separate trials in local areas with different conditions where we hope to demonstrate suppression of the dengue mosquito.”

About Dengue Fever: (Taken from the World Health Organisation factsheet)

Dengue Fever is a virus spread by the bite of an infected mosquito. There is neither medication nor a vaccine to prevent Dengue Fever. Effective measures to control the dengue mosquito Aedes aegypti are urgently required as globally the disease is becoming geographically more wide-spread, more prevalent and more virulent. The incidence of dengue has increased 30 fold in the last 50 years and according to WHO now 2.5Bn people are at risk. The severe form of dengue, known as Dengue Haemorrhagic Fever, was first recognized as recently as the 1950s but today has become has become a leading cause of hospitalization and death among children in Asian and Latin American countries.

About Oxitec (www.oxitec.com)

Oxitec is developing and commercialising an effective and environment-friendly proprietary technology for the control of significant insect pests. Oxitec’s technology has the potential to make a major contribution for both global health and agriculture by combating insects responsible for serious diseases such as dengue fever as well as agricultural damage. The proprietary technology builds on inventions from the University of Oxford and employs genetics and molecular biology to enhance the existing radiation based Sterile Insect Technique (SIT), and to extend the control method to a broader range of insect pests.

Contact mediarelations@oxitec.com

+44 1235 832393

About Moscamed (www.moscamed.com.br)

Moscamed is a leading exponent of the Sterile Insect Technique (SIT), an environmentally friendly and proven technique to control insect pests. Moscamed provide both monitoring services and carry out SIT programmes for the control of fruit flies in Brazil.

Contact iana@moscamed.org.br

+55 74 3612-5399