Summary of Program

The term “arbovirus” is short for arthropod-borne virus, and is used to describe diseases that may
be transmitted to humans by the bite of an arthropod. The three arboviruses routinely monitored
by the Health Department are West Nile Virus (WNV) and Eastern Equine Encephalitis (EEE) which
are transmitted by mosquitoes, and Lyme Disease which is transmitted by the deer tick.
 
WNV & EEE Surveillance: There are three components to Manchester’s WNV/EEE surveillance program including bird surveillance, mosquito surveillance, and human surveillance. Bird surveillance is used to learn whether dead birds were infected with WNV or EEE. The presence of WNV or EEE infected birds in a community is used as an indicator as to the presence of disease, but does not represent an immediate human risk. Mosquito surveillance is conducted across the City from June through mid-October to identifying mosquitoes that may be carrying WNV or EEE. The presence of virus-positive mosquitoes indicates that the vector for the spread of these diseases is present in a community, and that the risk to humans has substantially increased. Finally, the Health Department works 
with area health care providers to identify patients that may be ill due to infection with WNV, EEE and Lyme Disease. If confirmed, these patients are followed up to help understand where and how they may have become infected. 

WNV & EEE Control: The key to preventing mosquitoes from reaching a life stage by where they can bite and transmit disease is to limit their opportunities to breed. In 2001 the City enacted an Ordinance that requires residents to maintain their property in such a manner that prevents the breeding of mosquitoes. Despite the best efforts at preventing mosquito breeding, there are times when the control of adult mosquitoes through spraying becomes warranted. The decision to spray is made when there is a clear public health threat to the community. The Health Department has a Special Permit from the NH Department of Agriculture that allows for spraying to control mosquitoes during a public health emergency.

Public Education: The most important element of the arbovirus program 
is educating the public on the prevention of mosquito breeding, as well as 
the personal protective measures one can take to prevent mosquito and tick
bites. The Department works with the local media, other city departments,
and local organizations to help get this important information out to the
public.

Program Notes and Trends: Since 2000, when West Nile Virus was
first identified in Manchester, the Health Department has been actively
engaged in arbovirus surveillance and control. The purpose of an arbovirus
surveillance and control program is to minimize the risk to Manchester’s
residents of being exposed to and infected with mosquito-borne diseases. 
As we continue to learn more about the epidemiology of mosquito-borne
diseases in New Hampshire, good surveillance, control and public education will be needed on an ongoing
basis protect the public health in Manchester.