Does it matter if the county next to you does vector control? YES!

ABSTRACT: Vector-borne disease transmission is often typified by highly focal transmission and influenced by movement of hosts and vectors across different scales. The ecological and environmental conditions (including those created by humans through vector control programmes) that result in metapopulation dynamics remain poorly understood. The development of control strategies that would most effectively limit outbreaks given such dynamics is particularly urgent given the recent epidemics of dengue, chikungunya and Zika viruses. We developed a stochastic, spatial model of vectorborne disease transmission, allowing for movement of hosts between patches. Our model is applicable to arbovirus transmission by Aedes aegypti in urban settings and was parametrized to capture Zika virus transmission in particular. Using simulations, we investigated the extent to which two aspects of vector control strategies are affected by human commuting patterns: the extent of coordination and cooperation between neighbouring communities. We find that transmission intensity is highest at intermediate levels of host movement. The extent to which coordination of control activities among neighbouring patches decreases the prevalence of infection is affected by both how frequently humans commute and the proportion of neighbouring patches that commits to vector surveillance and control activities. At high levels of host movement, patches that do not contribute to vector control may act as sources of infection in the landscape, yet have comparable levels of prevalence as patches that do cooperate. This result suggests that real cooperation among neighbours will be critical to the development of effective pro-active strategies for vector-borne disease control in today’s commuter-linked communities.

Read the full article: Stone CM, Schwab SR, Fonseca DM and Fefferman NH 2017 Human movement, cooperation and the effectiveness of coordinated vector control strategies. J. R. Soc. Interface 14: 20170336. http://dx.doi.org/10.1098/rsif.2017.0336c

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Pesticide Recertification Course coming in October!

Course Description: This course meets pesticide applicators in need of credits before their pesticide applicator license expires in October. The training has been tailored for government employees with immediate concerns and responsibilities for stewardship of public health, mosquito research, surveillance and control. All who need re-certification credits in the above categories are welcome to sign up.

Topics for this one day course include:

9:45 AM – Registration & Coffee
10:00 Bionomics of Rare Mosquitoes Found in New Jersey
Scott Crans, Office of Mosquito Control Coordination
10:30 Pesticide Update for 2017
Dr. George Hamilton, Rutgers Department of Entomology
11:00 From Aerial Spraying to Beekeeping Practices, What are The Effects of Mosquito Abatement on Honeybees?
Dr. Diana Carle, Rutgers Department of Entomology, Center for Vector Biology
11:30 Lunch Break- Light Lunch Provided
12:30 Advances in Vector Control Science: Rear-and-Release Strategies Show Promise… but Don’t Forget the Basics
Dr. Brian Johnson, Rutgers Department of Entomology, Center for Vector Biology
1:00 Amplification and Transmission Cycles: Turn Up the Volume!
Dr. Lisa Reed, Rutgers Department of Entomology, Center for Vector Biology
1:30 Demonstration and Research: Mosquito Insecticide Resistance Management
Dr. Dina Fonseca, Rutgers Department of Entomology, Center for Vector Biology

Come join the fun! For more information and to sign up, click here.

Upcoming Webinars

The Northeastern Integrated Pest Management at Cornell will be hosting three webinars in September 2017 that could be of interest to people following arboviruses, disease, vectors, pests and/or control. Their webinar series, called “The IPM Toolbox” will include:

  1. 11 September 11:00 am – 12:00 pm Laura Harrington will talk about the erstablishment of the Northeast Regional Center for Excellence in Vector Borne Diseases.
  2. 13 September 11:00 am – 12:00 pm Scott Isard will talk about iPIPE or the integrated Pest Information Platform for Extension and Education.
  3. 25 September 11:00 – 12:00 A Team of people, including Rick Cooper and George Hamilton, will discuss the Brown Maromorated Stink Bug and control.

For more information, see http://www.northeastipm.org/ipm-in-action/the-ipm-toolbox/

 

Surveillance with Stable Isotopes

ABSTRACT

Stocking pen-raised northern bobwhite (Colinus virginianus) into habitats inhabited by wild bobwhite is a widespread practice, yet no technique other than marking exists to distinguish between these birds when they are harvested or recaptured. We assessed the potential of stable isotope analysis of primary feather tissue to distinguish between wild and pen-raised bobwhite. We obtained 104 feather samples from 3 game farms and 3 hunters in New Jersey, USA, collected between 1998 and 2006. We analyzed all samples for isotopes of carbon13C/12C, nitrogen15N/14N, sulfur34S/32S, and a preliminary sample for hydrogen2H/1H. Combinations of isotopic ratios of carbon, nitrogen, and sulfur yielded unique patterns for the 2 groups, enabling us to form a significant function that discriminated between these groups 100% of the time. The function was influenced most by the isotopic ratios of nitrogen and carbon. We were unable to discriminate between age classes or sex within groups, but could discriminate among farms and between years for the one farm where we had 2 years of samples. In our pilot study, stable isotope analysis of primary feather tissue was a reliable technique for distinguishing wild and pen-raised bobwhite for 12–14 months following postjuvenal or postnuptial feather molt. Summer stocking, feeding stations, or long-term survival of pen-raised birds would reduce the efficacy of this technique, depending upon the definition of a wild population. © 2017 The Wildlife Society.

Castelli P and L Reed 2017 Use of stable isotopes to distinguish wild from pen-raised Northern Bobwhite. Wildlife Society Bulletin. http://onlinelibrary.wiley.com/doi/10.1002/wsb.746/full

Ehrlichiosis may be under-reported in NJ

From the abstract: The lone star tick, Amblyomma americanum, is a vector of Ehrlichia chaffeensis and E. ewingii, causal agents of human ehrlichiosis, and has demonstrated marked geographic expansion in recent years. A. americanum ticks often outnumber the vector of Lyme disease, Ixodes scapularis, where both ticks are sympatric, yet cases of Lyme disease far exceed ehrlichiosis cases. We quantified the risk for ehrlichiosis relative to Lyme disease by using relative tick encounter frequencies and infection rates for these 2 species in Monmouth County, New Jersey, USA. Our calculations predict >1 ehrlichiosis case for every 2 Lyme disease cases, >2 orders of magnitude higher than current case rates (e.g., 2 ehrlichiosis versus 439 Lyme disease cases in 2014). This result implies ehrlichiosis is grossly underreported (or misreported) or that many infections are asymptomatic. We recommend expansion of tickborne disease education in the Northeast United States to include human health risks posed by A. americanum ticks.

Read more here at EID ! NOTE: There is a Continuing Medical Education (CME) credit available (1.00 AMA PRA Category 1 ) upon participation in activity with this article. See the first page of the article for more information.

Reducing ticks by targeting hosts

Ixodes scapularis, taken by James Occi.

Ixodes scapularis, taken by James Occi. This was a photo used for the cover of of the book, “Lyme Disease: Why it’s spreading, how it makes you sick and what to do about it” by Alan Barbour.

From the Abstract: We describe a 2-yr trial to evaluate the ability of SELECT Tick Control System (TCS) host-targeted bait boxes to reduce numbers of host-seeking Ixodes scapularis nymphs in a residential neighborhood. After four successive 9-wk deployments, nymphal and larval I. scapularis infestation prevalence and intensity were significantly reduced on target small mammals. In addition, these deployments resulted in 87.9% and 97.3% control of hostseeking nymphs in treatment sites at 1 yr and 2 yr postintervention, respectively. Installation of a protective metal cover around the SELECT TCS bait boxes eliminated nontarget wildlife damage to bait boxes that resulted in failure of previous bait box types. The results are discussed in the context of the residential environment and future research needs.

Schulze T, R A Jordan, M Williams and M C Dolan 2017 Evaluation of the SELECT tick control system (TCS), a host-targeted bit box, to reduce exposure to Ixodes sxapularis (Acari: Ixodidae) in a Lyme disease endemic area of New Jersey. Journal of Medical Entomology, https://doi.org/10.1093/jme/tjx044

Recent Developments

Dr. Fonseca will attend a Strategic meeting of the Worldwide Insecticide resistance Network (WIN) that will be held in Rio de Janeiro, BRAZIL, from May 04-05, 2017. This meeting is supported by the WHO Research & Training program on Tropical Diseases (TDR) and the Department of Neglected Tropical Diseases (NTDs) and the US-Centers for Disease Control and Prevention (US-CDC).

A proposal entitled “Predicting the evolution of vector-borne disease dynamics in a changing world” by Dr. Fonseca was top rated in the NSF DEB Ecology of Infectious Diseases panel (five “excellent” and one “very-good”) and recommended for funding. Using Next-Generation genomics we will generate one of the first comprehensive datasets detailing the evolutionary potential of the major players in a complex multi-host disease system: avian malaria in endemic Hawaiian birds transmitted by invasive mosquitoes. Our results will help mitigate the anthropogenic impacts associated with invasive species and climate change, and can be translated directly into practical management recommendations. This 4 year $2,498,876 project is slated to start on July 2017.

A grant on”Climate Change, Nuisance Mosquito Populations, and Long-term Resilience of Coastal Salt Marsh Systems” was awarded to the Center for Remote Sensing & Spatial Analysis (CRSSA), the Center for Vector Biology (CVB) and the Jacques Cousteau National Estuarine Research Reserve (JCNERR) plus in collaboration with state and county mosquito agencies.