Letter to the Editor, 12 August 2019: Mosquitoes and EEE!

By Ann A Kiessling, PhD

Entomologists began predicting last year that 2019 could see markedly increased incidences of Eastern Equine Encephalitis, EEE, infections in Massachusetts. They were right, the first human case of EEE was reported in Plymouth County on Saturday, August 10. https://www.mass.gov/news/state-public-health-officials-announce-first-human-case-of-eee-in-the-commonwealth.

Prior to this, because of the sheer numbers of mosquitoes, as well as the marked increase in those [insects] testing positive for EEE, a serious frequently fatal infection of the central nervous system, nine communities in southeastern MA were elevated to the level of “Critical” risk, which prompted aerial spraying after dark last week in several communities https://www.mosquitoresults.com/.

The communities at “Critical” risk are Middleborough, Carver, Lakeville, Wareham, Rochester, Freetown, Acushnet, New Bedford and Marion.

Aerial spraying is not the first choice for mosquito control by any mosquito control professional. The first choice is to control mosquito numbers by limiting their habitat and by applying agents that target their larvae. According to the late Andrew Spielman, Harvard School of Public Health, mosquitoes are not an important food source to any species on earth; their eradication would not harm anyone.

But there are thousands of species of mosquitoes, each with its own life cycle, and dozens of mosquito species carry diseases. Efforts to eradicate Aedes aegypti, recently emerging as one of the vectors for Zika virus, began in this hemisphere over a hundred years ago in an effort to control malaria and yellow fever in the U.S. Those efforts, which included DDT, were highly successful and malaria and yellow fever were declared eradicated decades ago https://wwwnc.cdc.gov/eid/article/24/5/17-1609_article.

So if we know how to effectively control mosquito-borne diseases, why is EEE emerging at “Critical” levels in Massachusetts? This is an important question everyone needs to be asking our state and local government officials.

Part of the answer lies in the fractured nature of mosquito surveillance and control in the Commonwealth. Each township must “opt-in” to a district mosquito surveillance and control program, and not all areas of the state have one. Bedford budgets resources every year for surveillance and control by Eastern Middlesex Mosquito Control District because we have a history of an EEE outbreak in the mid-’80s. But neighboring communities such as Carlisle and Woburn have not “opted-in” so surveillance in those areas is incomplete.

Also, mosquito control professionals must try to negotiate with Fish and Wildlife preserve officials, such as Great Meadows National Wildlife Refuge, which has proven extremely difficult in past years. Although the Massachusetts Department of Public Health probably has the authority to conduct mosquito control activities in federal lands within the Commonwealth, this is a very grey legal area.

The good news is that in 2018, the U.S. Fish and Wildlife Service issued a new handbook for Mosquito Management on National Wildlife Refuges https://www.fws.gov/policy/MosquitoHandbook_6_2018.pdf. It calls for the organization of a contingency plan between wildlife refuge officials and local mosquito control professionals when evidence of the threat of disease emerges.

Which is where we are now – under threat from EEE. Our local, state and federal legislators need to IMMEDIATELY authorize the U.S. Fish and Wildlife contingency plan so our Middlesex Mosquito Control officials can do what they know how to do to protect Bedford and surrounding communities from EEE-infected mosquitoes.
Bedford’s state legislators are Mike Barrett www.gov/Legislators/Profile/MJB0 and Ken Gordon www.malegislature.gov/People/Profile/KIG1.

Our federal senators are Elizabeth Warren www.warren.senate.gov/, and Ed Markey https://www.markey.senate.gov/ and our representatives in the House are Ayanna Pressley, Bill Keating, Jim McGovern, Joseph Kennedy III, Katherine Clark, Lori Trahan, Richard Neal, Seth Moulton, and Stephen Lynch.