Q&A: CDC collaborates on guide for mosquito control after natural disasters
The CDC and the American Mosquito Control Association collaborated to create the first-ever resource that can be used to guide mosquito control in areas affected by natural disasters, including hurricanes and floods.
The resources are in a special issue of the Journal of the American Mosquito Control Association, which includes research, real-world examples of preparing and responding to natural disasters from a mosquito control standpoint, and lessons learned from past disasters.
One of the studies used a model to assess the effect of hurricane timing on the risk for human West Nile virus neuroinvasive disease (WNV-NID) on the northern coast of the Gulf of Mexico. According to the study, early-season hurricanes which typically make landfall before the peak of baseline WNV transmission activity increased the average total of potential mosquito vectors for the year by 7.8% and human WNV-NID incidence by 94.3% across all areas with hurricane damage.
Healio spoke with Roxanne Connelly, PhD, chief entomologist in the CDC’s Arboviral Diseases Branch, to discuss the special issue and the effect that natural disasters may have on mosquito-borne diseases.
Q: Who is this issue for and who should read it?
A: This special issue of the Journal of the American Mosquito Control Association is meant for any professional who might play a role in disaster response, including public health workers, mosquito control, emergency responders and government staff. Information included in this issue can help state and local entities plan for managing mosquitoes after a disaster and focus on recovery for their community.
Q: How do natural disasters like hurricanes and floods lead to an increase in mosquito-borne diseases?
A: Natural disasters, like hurricanes and flooding, can create new places for mosquitoes to lay eggs and potentially increase the risk for mosquito-borne diseases. Flooding caused by hurricanes can result in large populations of nuisance mosquitoes, which generally don’t spread viruses that make people sick but can hinder recovery activities. In addition to nuisance mosquitoes, populations of mosquitoes that can spread viruses, like WNV, may increase in the weeks following a hurricane, especially in areas that did not flood but received more rainfall than usual.
Q: Are there differences in how local, state and federal authorities should prepare and respond to natural disasters as they relate to mosquito-borne diseases?
A: In general, local government agencies are usually on the front lines of a disaster response, with state and federal governments assisting when things become complex and potentially overwhelming. It’s incredibly important for agencies at all levels of government to have well thought out plans in place for what to do before, during and after a natural disaster. Effectively controlling both nuisance mosquitoes and those that can make people sick after a natural disaster can help communities recover more quickly and avoid potential disease outbreaks.
Resources in this special edition of the Journal of the American Mosquito Control Association include real-world examples, research and lessons learned from authors representing federal and state agencies; mosquito control programs and health departments in Florida, Georgia, Mississippi and Texas; research organizations; and the military. Ensuring state and local agencies have the knowledge and resources they need to respond to public health issues in emergencies is a top priority of CDC.
Q: How can people prepare and respond to a potential rapid increase in the mosquito population?
A: Immediately following a hurricane, flooding occurs. Mosquito eggs laid in the soil by floodwater mosquitoes during previous floods hatch, resulting in very large populations of floodwater mosquitoes. Most of these mosquitoes are considered nuisance mosquitoes. The best way to prevent mosquitoes around your home is to regularly dump standing water in containers like flowerpots and kiddie pools, and to throw away debris around the home that may collect water, like old tires. You can keep mosquitoes out of your home by installing screens on your windows and doors. When outside, the best way to prevent mosquito bites is to cover up with long-sleeved shirts and pants and wear EPA-registered insect repellent.
Q: How about clinicians?
A: Clinicians should be aware that a number of infectious diseases can be seen following natural disasters, including mosquito-borne diseases. Mosquito-borne diseases may occur several weeks following a natural disaster if the mosquito population increases and people become infected and develop symptoms. It is important clinicians know which mosquito-borne diseases are common in their area and understand the clinical signs and symptoms. The most common mosquito-borne disease across the United States is WNV disease, which can range from mild to severe. Testing can be performed for common mosquito-borne diseases in the United States to help with possible diagnosis. Clinicians can find information on the various mosquito-borne diseases, their symptoms, diagnostic testing availability and treatment on their state or local public health website and at CDC’s website.