22 November 2017 – We had to wait until an official joint press release was issued by the NJ Dept. of Agriculture and NJ Dept. of Health yesterday, but on November 9 Andrea, using the barcode mtDNA sequence, identified an unknown tick that had been found in Hunterdon county, NJ back in August. The tick was brought to our attention by Jim Occi, who was contacted by the Hunterdon Department of Health that shrewdly had figured out the tick was “something different”. Shortly after, Andrea’s tick ID was confirmed by USDA-APHIS. It is Haemaphysalis longicornis, the “longhorned tick” or “bush tick”. This species is native to northeast Asia (China, Russia, Japan) but expanded into Australasia (Australia, New Zealand, Pacific islands) in the 1800’s or early 1900’s. While H. longicornis had been intercepted several times in United States ports of entry, there are no known established populations in the New World. This tick is decidedly an agricultural (livestock) pest and disease vector and it has been associated with human pathogen transmission, particularly in farmers and those handling livestock. The question in everyone’s mind is: will it survive the NJ winter? That will likely depend on where it came from.
Investigating the Ecology of Male Aedes polynesiensis in Tetiaroa to Improve Population Eradication using Wolbachia
It’s true, paradise does exist. And it is Tetiaroa. Tetiaroa is an atoll in the Windward group of the Society Islands in French Polynesia located 33 mi from Tahiti. The atoll has only 6 square kilometres (2 sq mi) of total surface area divided by 12 motus (islets), but it makes up for its modest size by encircling a truly world unique lagoon. The lagoon is approximately 7 kilometers wide and ranges in depth from only a few centimeters at the shore to 30 meters at its deepest point and is filled with clear, turquoise water and abundant marine life. The isolation and beauty of the atoll made it a top vacation spot for Tahitian royalty and in more recent times is known for having been purchased by and served as a primary residence for Marlon Brando. It is now home to The Brando, a luxury eco-resort. The allure of Tetiaroa attracted not only royalty but the mosquito Aedes polynesiensis, a vector of dengue, lymphatic filariasis and likely Zika virus, as well.
Ae. polynesiensis is a semi-domestic species found only in the South Pacific with an extremely wide range of breeding places that includes tree holes, a wide range of artificial containers, crab holes, canoes, coconut shells and husks, of which there are plenty on Tetiaroa. In addition to their vector status, they can cause great nuisance to locals and vacationers alike, destroying a long-awaited honeymoon or relaxing retreat. So, if you want to formulate a plan to eradicate a pest to improve paradise while also undertaking an ambitious experiment that could change how we fight mosquitoes and the diseases they spread, there is no better setting than Tetiaroa.
The project to eliminate Ae. polynesiensis from Tetiaroa is led by medical entomologist Hervé Bossin and his team at the Institut Louis Malardé in collaboration with the Tetiaroa Society, a non-profit research and conservation organization dedicated to understanding the wonders of Tetiaroa, and The Brando resort. The plan involves releasing large numbers of Wolbachia-infected male Ae. polynesiensis into the wild to reduce and eventually eradicate the species from the island. Wolbachia are a group of intra-cellular bacteria that live inside many insect species, including mosquitoes, and when a male mosquito infected with Wolbachia mates with a female not infected with Wolbachia, or infected with a different strain, the fertilized eggs fail to develop due to what is called cytoplasmic incompatibility. Hervé and his team have already released more than 1 million sterile male mosquitoes on the island starting in 2015, triggering a hundredfold drop in the mosquito population. Today, over a year after the end of releases, the mosquito population on the islet of Onetahi where the study took place is 1/10th what is was prior to the Wolbachia releases.
However, there is still much to learn before additional releases are performed. In particular, male Ae. polynesiensis ecology is still poorly understood. Questions such as, “how far will a male fly?” and “how long does a male live?” are still unanswered. It is essential to answer these and many other questions to optimize future releases and maximize population suppression. To help fill in these knowledge gaps, Hervé and ILM have arranged for a gathering of some of the world’s premier medical entomologists and mosquito ecologists for a workshop on male-based control strategies, including Wolbachia. Prior to the workshop, a small group of researchers, including myself (Brian), will perform a series of mark-release-recapture experiments on Tetiaroa. These experiments will involve the release of 45,000 male Ae. polynesiensis marked with fluorescent powder to obtain accurate estimates on male dispersal (flight range) and survivorship post-release, as well as investigations into novel male surveillance strategies.
The experiments have yet to take place, but we are already excited about the outcomes! More updates on the workshop and MRR experiments will follow shortly.
EPA registered Aedes males with a modified Wolbachia for release in DC and 20 US states (including NJ)
7 November 2017 – On Nov. 3, EPA registered a new mosquito biopesticide – ZAP Males®. ZAP Males® are live male mosquitoes that are infected with a strain of the Wolbachia bacterium (named ZAP) that is incompatible with existing Aedes albopictus Wolbachia strains. ZAPMales® can be used in sterile male technique (SIT) approaches. Tests of efficacy are still lacking but proof of principle, especially the ability of releasing males without changing the makeup of local Wolbachia infections has been accomplished (Mains et al 2016). And here’s a link to a Nature article on the subject: https://www.nature.com/news/us-government-approves-killer-mosquitoes-to-fight-disease-1.22959
The Fonseca Lab would like to officially welcome Melvin DelVillar to our lab. He is an undergraduate student in the School of Environmental and Biological Sciences at Rutgers University, and is pursuing a BS in both Entomology and Kinesiology & Health. Melvin hopes to become a MD specializing in infectious diseases and tackling the issue of vector-borne diseases.
At Rutgers University, Melvin is an executive board member of the American Medical Student Association (AMSA) where he coordinates events and seminars that help prepare students for the rigors of medical school and the pre-medical tract.
Melvin is interested in the relationship between arthropod transmitted vector-borne diseases and people, and how this relationship changes over time and space. As a lab technician in the Fonseca Lab, Melvin is currently researching the expansion of invasive species of potential vectors in northern parts of New Jersey.
Melvin is a running enthusiast and is a member of the Rutgers Running Club and the Garden State Track Club.
19 October 2017 – Dina attended a (almost) all day retreat to define the mission of the Rutgers Global Health Institute. She contributed to the inclusion of foci in vector-borne diseases and urban health as well as the importance of direct community engagement (will follow up with colleagues she met from the School of Public Health and Information & Communications). The Global health Institute is a new Rutgers venture, the Director, Dr. Richard Marlink joined a year ago.
October 11, 2017 – Rafael, Anne Nielsen and Dina met up with Sven-Erik Spichiger (PA Department of Agriculture) and visited sites in Pennsylvania infested with the spotted lanternfly (SLF), Lycormia denticulata. A beauty and a beast. SLF was first detected in eastern PA (Berks county) in 2014 and has since spread to five others (Bucks, Montgomery, Chester, Lehigh and Northampton). Arrival in NJ is imminent and we need to be pro-active. Rafael carefully collected samples of honeydew, soil, leaves covered in sap and black mold. Will there be detectable SLF DNA?? That is the question. For the answer, keep tuning in.
Samantha Rose Schwab, a mathematical modeler finishing her PhD with Dr. Nina Fefferman at U. Tennessee, is sharing an office with Agnesa downstairs in McLean. Funded by a NSF Zika RAPID Sammi has been examining the effects of timing and scale of mosquito control on Zika transmission. Go visit: they have an expresso making coffee machine (!) Sammi will give a presentation on her research at lab meeting on October 19.
Prof. Scott Ritchie visited Brian and the Fonseca Lab in mid August and left a “path of construction”! He spent a day in the salt marsh with Brian, Dina and Rick Lathrop (the PI of the NOAA funded salt marsh mosquito project) and back in the lab taught us how to collect and identify mosquito egg shells to assess marsh productivity. The next day, Dina took Scott and Brian to a town in Maryland developing a Citizen AcTS project where residents are deploying passive lethal oviposition traps (GATs) for urban Aedes control. The GATs were co-invented by Dr. Ritchie. Scott met the Mayor and marveled at the town’s lush gardens and tall trees, perfect to sustain large populations of Asian tiger mosquitoes.
Agnesa with her dog Laima on the left, and her former foster dog Willow on the right
The Fonseca Lab would like to welcome Agnesa Redere as the newest member of our lab. Agnesa is a PhD student in the Department of Ecology & Evolution at Rutgers University. Her research interests focus on evaluating expected utility in three scenarios of ecological importance: epigenetics in changing environments, in proactive versus reactive mosquito control strategies in curtailing the spread of Zika virus, and inthe psychological concept of priming in changing environments. Agnesa uses mathematical modeling and simulations to generate understanding of these concepts.
At Rutgers University, Agnesa is a member of the Rutgers Academy for the Scholarship of Teaching and Learning (RASTL), which allows her to meets with faculty members and administrators on a monthly basis to discuss higher education and the issues centered on undergraduate instruction. Also, she is an Assistant Head Teaching Assistant (AHTA) for General Biology courses that are offered at Rutgers University.
Prior to her graduate studies, in 2011 Agnesa received her Associates of Science degree in Biology from Sussex County Community College. After graduating, she traveled south to Rutgers University to continue her learning trajectory in the sciences and earned a Bachelor of Science degree in Chemical Engineering in 2014.
In her spare time, Agnesa trains people and on how to teach their dogs basic obedience. In addition, she also trains her own dog in sports such as nosework, tricks, obedience and agility. Agnesa is a member of the American Belgian Malinois Rescue where she fosters and places dogs who are in need of their forever homes.