Fleas, ticks, other bugs, and animals can carry serious diseases that affect humans. These are vector-borne and zoonotic illnesses.
Vector-Borne and Zoonotic Illnesses
Zoonotic diseases are ones that transmit from animals to humans, while vector-borne diseases are carried by bugs (such as ticks, fleas, or mosquitoes) to others. Some well-known zoonotic illnesses are rabies, monkey pox, and avian (bird) flu. Plague is a flea-borne (vector) disease, Lyme disease is transmitted by ticks, and West Nile Fever is a mosquito-borne illness.1 Other vector-borne diseases include Rocky Mountain Spotted Fever, Eastern equine encephalitis, and dengue fever. Viral hemorrhagic fevers are transmitted via the bites of ticks and mosquitoes. Lice are responsible for epidemic typhus. Plague, also a zoonotic disease, can transmit via the handling of infected animals. Hantavirus is passed on through rodents. Mammals can carry rabies. La Crosse encephalitis, ehrlichiosis, and Southern Tick Associated Rash Illness (STARI) are other vector diseases.2 Additional illness that are transmitted via insects include yellow fever, malaria, sleeping sickness, filariasis, leishmaniasis, and the chikungunya virus.3 Vector-borne diseases could be parasitic, bacterial, or viral in nature.4
Treatments and Prevention
Some of the prior vector-borne illnesses have become more uncommon due to vaccinations and hygiene. Others, which had been disappearing, are re-emerging. Changes in climate and ecology have led to some illnesses spreading. Malaria is a risk for travelers to tropical regions. Lyme disease requires treatment with antibiotics. There are vaccines for some of the other illnesses. Some diseases only have treatments that resolve symptoms (e.g., fever, rash, and pain management), but the disease itself may carry its own immunity, such as with the chikungunya virus. Dengue fever, in contrast, does not carry immunity and leaves the patient at risk of more severe viral infections. Yellow fever includes symptoms of fever, headache, and low back pain, with later stages including black vomit, jaundice, and hemorrhaging. Fortunately there is a vaccination travelers can take. Prevention of mosquito bites is also important, especially in certain regions of the world.5 The World Health Organization (WHO) has many responses that it takes regarding vectors. They provide support and advice to manage outbreaks, as well as training, tools, insecticides, and other technologies to control vectors. Aside from helping countries learn prevention, the WHO also provides medicine and helps governments with clean water and sanitation.6 The Centers for Disease Control (CDC) also work to educate the public and prevent the spread of outbreaks. Their website provides resources for understanding various diseases, including those transmitted by rodents. The CDC website has information about transmission, diagnosis, treatment, prevention, and control, as well as risk factors and travel advisory information.7