[Mosquito Control] Mosquitoes: from nuisances to nightmares

Author’s note: Individuals from throughout the U.S. and many parts of the world attended the American Mosquito Control Association (AMCA) annual meeting in Sparks, Nev., in March. Mosquito control professionals from academia, government and the private sector gathered to learn about the latest in research, new innovative control products and the ongoing control programs at local, state and national levels. What follows is a review of that meeting.

Although it was only early March, and not a mosquito was in sight in Sparks, Nev., mosquito experts from the U.S. and international community gathered at John Ascuaga’s Nugget Casino Resort for the American Mosquito Control Association’s 74th annual meeting. Attendance at this year’s meeting climbed to more than 1,000 participants, one of the largest meetings yet.

On a worldwide basis, mosquito-borne pathogens result well in excess of 1 million deaths each year. Some estimates claim those numbers are as high as 5 million deaths, with hundreds of millions others impacted. It is difficult to calculate such a number on a global basis, especially in developing countries with bulging populations, poor living conditions and a lack of medicine and medical care. A huge number of these deaths can be attributed to malaria, mainly in African countries. 

Despite all that is known about the malaria parasite Plasmodium spp. and the hosts and vectors in the life cycle of the parasite, which have been studied for decades, malaria remains one of the most devastating killers on the planet, following only HIV/AIDS and lower respiratory infections. 

In the United States most people worry very little about malaria unless they are traveling outside the country — but what about West Nile virus? With tens of thousands of cases throughout the United States since 1999 resulting in more than 1,000 fatalities, this mosquito-vectored virus has drawn the attention of academics and public health officials alike in the United States.

IMPORTANT DIALOGUE OPENED. The AMCA meeting, which is usually held each year in early March, serves to disseminate information to vector control industry professionals, educators, academics and public heath officials, as well as students.

Attendees at this year’s event were able to learn about the latest university and industry research on the behavior and biology of a variety of mosquito pests as well as state regulatory issues and public health concerns. In the exhibit hall attendees learned about the latest vector control equipment and hardware, and met with industry representatives of mosquito adulticides and larvacides.

For young students or old pros alike the meeting is one of the top places to network with other mosquito experts from all over the country and around the world. The following briefly describes some of the highlights of the meeting.

SPIELMAN HONORED. The 2008 Memorial Lecture Honoree was Dr. Andrew Spielman. Spielman, who passed away in 2006, was a world-renowned expert on vector-borne illnesses such as malaria, Lyme disease and babesiosis. He was a major figure in the modern history of public health entomology. Spielman earned a Sc. D. in the malaria lab at Johns Hopkins University in 1952, serving thereafter as a public health entomologist in the U.S. Navy (he retired as a Lieutenant Commander). In 1959, Spielman served as public health entomologist and professor of Tropical Public Health in the Department of Immunology and Infectious Diseases at the Harvard School of Public Health (HSPH). 

The lecture was given by Dr. John Edman, recently retired professor and mosquito expert from the University of California, Davis. Edman provided a thorough review of the research conducted by Spielman during his 48-year career, including his work on juvenile hormone (JH) mimics to control mosquito larvae, physiology and population biology of Culex pipiens and Aedes aegypti.

PRODUCTS AND TREATMENTS. Monday afternoon symposia included “IPM application techniques for effective mosquito control,” “Legislative and Regulatory Issues,” and “Behavior and Biology (of mosquitoes).” Presenters covered topics on larvacides, aerial adulticide application, surveillance/monitoring, methods for treating floodwater mosquitoes, studies on male mosquito longevity, dispersal and mating, as well as others. 

An interesting aspect of this year’s AMCA meeting was the 18th annual Latin American symposia organized by Dr. Gary Clark and Yasmin Rubio-Palis. In these symposia, presenters/researchers gave their talks in their native Latin American language (translators and headsets were available for attendees). There were about 40 talks in this split multi-session. Topics ranged from discussions on community-based surveillance in rural Mexico, oviposition traps (female mosquitoes lay their eggs) for monitoring Aedes aegypti in Brazil, resistance mechanisms to temephos in A. aegypti in Peru, evaluation of dengue transmission in areas of low population in Columbia, and evaluation of malaria within a high-altitude mountain system in Bolivia.

A symposia that was dedicated entirely to larval control included discussions about methods for treating standing water to kill immature stages of the mosquitoes prior to them becoming biting adults. Conventional microbial insecticides and JH mimics were the topic of several papers as were more novel methodologies such as acoustic disruption of larvae in wastewater treatment plants, mosquitofish (Gambusia spp.) production in salt marshes and alteration of marsh space to reduce adult mosquito production.

Rui-De Xue, Linda Wampler and Jeanne Moeller organized and moderated a symposia on pesticides and the environment with six papers that covered novel botanical insecticides and their fate in the environment, resolutions for butterfly-mosquito control conflicts, the impact of mosquito adulticides and larvicides on non-target organisms and a study to understand the effects of laundering on bite-protection and insecticide content of the combat uniforms of the U.S. Marine Corps.

On Wednesday morning, a series of papers addressed insect repellents as a public health strategy. This symposia discussed topics of how to understand the results of a mosquito repellent test; how to communicate efficacy of repellents; what consumers should know about insect repellents; recent improvements to consumer product formulations; and the question of “What is the role for personal repellents in public health?”

The final day had a number of interesting concurrent sessions — including “Mosquito research groups: What are they up to today?” — a session that consisted of reports by several large university programs across the country and the specific research projects their scientists are involved with. Mosquito systematics and the latest GPS/GIS technologies also were discussed in respective symposia.

Finally, Dr. Stanton Cope organized and moderated a symposium titled “The deployed war fighter protection program — Finding new ways to vanquish ancient foes.” This session covered a variety of research projects around the country at university and government laboratories that are looking for novel but applicable methods for protecting deployed U.S. soldiers.   

COMMON GOALS. Historically there has been a separation between urban entomologists/pest management professionals that study and provide control measures and for general household pests and those entomologists/pest professionals that study and control mosquitoes (e.g., medical entomologists/vector control professionals). However, these groups have always shared common goals, keenly focused on providing a better and safer life for all members of society. 

The next time pest management professionals need some additional mosquito training, or simply would like to gain a fresh perspective on these pests, they should consider attending this meeting. In many parts of the world and in the United States as well, mosquitoes continue to be a nuisance and a public health threat to humans.

The author is an entomologist living in Racine, Wis.

Next AMCA meeting in New Orleans

The 75th Annual AMCA meeting will be held April 5-9, 2009, in New Orleans. For more information, contact the American Mosquito Control Association, 856/439-0525 or e-mail amca@mosquito.org.