Overview
According to the World Health Organization (WHO), vectors are living organisms (e.g., ticks) that can transmit infectious pathogens between humans or from animals to humans. Vector-borne diseases (VBDs) are human illnesses caused by parasites, viruses and bacteria that are transmitted by vectors.
Causes and Spread
The CDC states that there are a number of factors that drive the spread of VBDs. Changes in land use patterns create changes in deer populations that expose individuals to infected tick bites. Global travel and trade introduce different vectors to areas to which they are not native. Climate change shifts weather patterns and temperatures that can lengthen vector seasons. Additionally, societal factors like housing conditions, occupational exposures and healthcare access contribute to increased risks of VBDs.
Vector-Borne Diseases in Your Area
The CDC’s tick bite data tracker can be used to follow tick bites reported by region, age and sex.
In the Northeastern United States, Lyme disease (characterized by fever, rash and arthritis), anaplasmosis (symptoms may begin one to two weeks after a tick bite) and babesiosis (caused by a parasite, impacting red blood cells) are the most common tick-borne illnesses, and are transmitted by the black-legged tick. The most common mosquito-borne illnesses are West Nile virus, which can result in mild flu-like symptoms or severe illness, and eastern equine encephalitis virus (EEEV), a rare but serious disease.
In the Southern United States, Lyme disease, transmitted by the black-legged tick, is the most common tick-borne illness. The most common mosquito-borne illnesses are West Nile virus and La Crosse encephalitis, which can begin without symptoms.
One tick or mosquito can carry multiple pathogens, so it is important to speak with your healthcare provider about appropriate testing and treatment.
What You Can Do
Prevention
Use an insect repellent with one of the following ingredients: DEET, picaridin, IR3535, oil of lemon eucalyptus, para-menthane-diol (PMD) or 2-undecanone when spending time outside. EPA’s search tool can assist with finding the right product for you. If you plan to spend extensive time outside, consider treating your clothing, gear and shoes with permethrin. Wear long, loose and light colored clothing to make it easier to see ticks on your clothing. If you are using sunscreen, apply sunscreen first and insect repellent second.
After returning indoors, check your body, clothing, gear and hair for ticks. Showering within two hours of returning indoors reduces the risk of contracting Lyme disease and is a good opportunity to do a complete tick check. Additionally, if you have pets, also check them for ticks. If you find a tick attached, use a pair of tweezers to remove it, getting as close to the mouth parts as possible.
Individuals planning to travel to areas with risk of chikungunya, Japanese encephalitis, tick-borne encephalitis and Yellow fever should discuss vaccination with their healthcare provider. Students can make appointments at the Student Health Center online or by calling 202-687-2200; booking in advance is highly recommended. The Infectious Diseases team at MedStar Georgetown University Hospital also offers comprehensive travel care, and appointments can be requested online.
Symptoms
Symptoms of vector-borne diseases can vary depending on the infection, but may include fever, chills, headache, fatigue, muscle and joint aches, rash or swollen lymph nodes. Some diseases may cause more severe symptoms such as neurological changes, bleeding or difficulty breathing. Individuals who develop symptoms after a known or possible exposure to vectors should seek medical evaluation promptly.
Diagnosis
If you are concerned that you have been infected with a VBD, reach out to your healthcare provider, the Student Health Center if you are a student or the Infectious Diseases team at MedStar Georgetown University Hospital for individual diagnosis and treatment options.