Nine new germs 

spread by mosquitoes 

and ticks have 

been discovered or 

introduced since 2004. 

About 80% of vector 

control organizations lack 

critical prevention and 

control capacities.

9

8 in 10

3x Disease cases from 

mosquito, tick, and flea 

bites tripled in the US from 

2004 to 2016. 

Want to learn more? 

Visit: www.cdc.gov/vitalsigns

MAY. 2018

#vitalsigns

Illnesses on the rise 

Almost everyone has been bitten by a mosquito, tick, or flea. 

These can be vectors for spreading pathogens (germs). A 

person who gets bitten by a vector and gets sick has a vectorborne disease, like dengue, Zika, Lyme, or plague. Between 

2004 and 2016, more than 640,000 cases of these diseases 

were reported, and 9 new germs spread by bites from infected 

mosquitoes and ticks were discovered or introduced in the 

US. State and local health departments and vector control 

organizations are the nation’s main defense against this 

increasing threat. Yet, 84% of local vector control organizations 

lack at least 1 of 5 core vector control competencies. Better 

control of mosquitoes and ticks is needed to protect people 

from these costly and deadly diseases. 

State and local public health agencies can

• Build and sustain public health programs that test 

and track germs and the mosquitoes and ticks 

that spread them. 

• Train vector control staff on 5 core competencies 

for conducting prevention and control activities. 

http://bit.ly/2FG1OMw

• Educate the public about how to prevent bites 

and control germs spread by mosquitoes, ticks, 

and fleas in their communities. 

From mosquito, tick, and flea bites
More cases in the US 

(2004-2016)

• The number of reported cases 

of disease from mosquito, 

tick, and flea bites has more 

than tripled. 

• More than 640,000 cases of 

these diseases were reported 

from 2004 to 2016. 

• Disease cases from ticks have 

doubled. 

• Mosquito-borne disease 

epidemics happen more 

frequently.

More germs (2004-2016)

• Chikungunya and Zika viruses 

caused outbreaks in the US 

for the first time. 

• Seven new tickborne germs 

can infect people in the US. 

VECTOR-BORNE DISEASES 

REPORTED BY STATES TO CDC

Disease cases from infected mosquitoes, ticks, and fleas have tripled in 13 years.

Mosquito-borne diseases

• California serogroup viruses

• Chikungunya virus 

• Dengue viruses

• Eastern equine encephalitis virus

• Malaria plasmodium

• St. Louis encephalitis virus 

• West Nile virus 

• Yellow fever virus 

• Zika virus 

PROBLEM:

Increasing threat, 

limited capacity to respond 

SOURCE: CDC Vital Signs, May, 2018

DISEASE CASES IN THE US 

More people at risk

• Commerce moves mosquitoes, ticks, and 

fleas around the world. 

• Infected travelers can introduce and 

spread germs across the world. 

• Mosquitoes and ticks move germs into 

new areas of the US, causing more people 

to be at risk. 

The US is not fully prepared

• Local and state health departments and 

vector control organizations face increasing 

demands to respond to these threats. 

• More than 80% of vector control 

organizations report needing 

improvement in 1 or more of 5 core 

competencies, such as testing for 

pesticide resistance.

• More proven and publicly accepted mosquito 

and tick control methods are needed to 

prevent and control these diseases.

27,388

96,075

2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016

100,000

80,000

60,000

40,000

20,000

10,000

30,000

50,000

70,000

90,000

0

Tickborne diseases 

• Anaplasmosis/ehrlichiosis

• Babesiosis

• Lyme disease

• Powassan virus 

• Spotted fever rickettsiosis

• Tularemia

Fleaborne disease

• Plague 

FOR MORE INFORMATION: 

https://wwwn.cdc.gov/nndss/
SOURCE: Rosenberg R, et al. Trends in Reported Vector-Borne

Disease Cases—United States and U.S. Territories, 2004-2016. 

MMWR Morb Mortal Wkly Rep. Vol. 67, 2018.

SOURCE: NACCHO, http://bit.ly/2FG1OMw

1. Monitor and track mosquitoes and ticks locally. 

2. Use data to drive local decisions about vector control. 

3. Have an action plan to kill mosquitoes and ticks at 

every life stage.

4. Control vectors using multiple types of methods.

5. Conduct pesticide-resistance testing. 

DISEASE CASES FROM MOSQUITOES (2004-2016, REPORTED) 

DISEASE CASES FROM TICKS (2004-2016, REPORTED)

Recent outbreaks of Zika, chikungunya, and West Nile viruses and the steady increase in Lyme 

disease cases point to the need for state and local agencies to have comprehensive vector-borne 

disease prevention and control programs. The US needs better tools and more staff with greater 

expertise at local and state levels to reduce the growing threat of these diseases in the US. 

CONTROLLING DISEASES FROM 

MOSQUITOES AND TICKS 

REQUIRES 5 CORE COMPETENCIES. 

Local health departments and vector control 

organizations must be able to:

DISEASES FROM MOSQUITO 

AND TICK BITES OCCUR IN 

EVERY STATE AND TERRITORY. 

* All states and territories in this quintile 

fell between 1,678 and 9,254, with the 

exception of Puerto Rico, which had 

80,534 cases.

Maps show case counts, not disease risk.

Maps show case counts, not disease risk.

Disease counts include both locally transmitted and travel-associated cases.

ALASKA

HAWAII

PUERTO RICO

US VIRGIN ISLANDS

AMERICAN SAMOA

ALASKA

HAWAII

PUERTO RICO

US VIRGIN ISLANDS

AMERICAN SAMOA

Top 20% (more than12,856)

2nd 20% (2,141-12,856)

3rd 20% (1,099-2,140)

4th 20% (183-1,098)

Bottom 20% of states (117-182)

None: 0

Top 20% (more than 1,678)*

2nd 20% (1,138-1,678)

3rd 20% (545-1,137)

4th 20% (313-544) 

Bottom 20% of states (87-312) 
THE FEDERAL GOVERNMENT IS

• Funding states, territories, industry, university, 

and international groups to detect and respond 

to infections from mosquitoes, ticks, and fleas 

and report cases to CDC.

http://bit.ly/2GvmyDH

• Convening a Tick-Borne Disease Working Group 

established by the 21st Century Cures Act 

to improve federal coordination of tickborne 

disease efforts.

• Supporting 5 regional centers of excellence to 

address emerging diseases from mosquitoes 

and ticks. https://www.cdc.gov/vector

• Conducting and developing diagnostic tests, 

vaccines, and treatments for these diseases.

• Educating the public about protecting 

themselves from diseases resulting from an 

infective mosquito, tick, or flea bite. 

https://www.cdc.gov/vector

STATE AND LOCAL GOVERNMENT 

AGENCIES CAN

• Build and sustain public health programs that 

test and track germs and the mosquitoes and 

ticks that spread them.

• Train vector control staff on 5 core competencies 

for conducting prevention and control activities. 

http://bit.ly/2FG1OMw

• Educate the public about how to prevent bites 

and control germs spread by mosquitoes, ticks, 

and fleas in their communities.

UNIVERSITIES AND COMPANIES CAN

• Study mosquitoes and ticks to better understand 

how to control them.

• Develop new or better methods and products to 

kill mosquitoes and ticks at each stage of life.

• Discover or improve tests for diagnosing new 

and known diseases from infective mosquito and 

tick bites.

• Create and sustain information-sharing networks.

• Train the next generation of entomologists and 

vector control professionals.

EVERYONE CAN

• Use an Environmental Protection Agency-registered 

insect repellent. http://bit.ly/2tIJyLl

• Wear long-sleeved shirts and long pants.

• Treat items, such as boots, pants, socks, and tents, 

with permethrin or buy permethrin-treated clothing 

and gear.

• Take steps to control ticks and fleas on pets.

• Find and remove ticks daily from family and pets. 

http://bit.ly/2nSlO3S

• Take steps to control mosquitoes, ticks, and fleas 

inside and outside your home. 

http://bit.ly/2aexzI4 

http://bit.ly/2DbY6E3

CS290757-A

For more information, please contact

Telephone: 1-800-CDC-INFO (232-4636)

TTY: 1-888-232-6348 | Web: www.cdc.gov

Centers for Disease Control and Prevention

1600 Clifton Road NE, Atlanta, GA 30333

Publication date: May 1, 2018

www.cdc.gov/vitalsigns/vector-borne

www.cdc.gov/mmwr

WHAT CAN BE DONE