vector borne diseases

vector-borne diseases

-any living creature that transmits an infectious agent to humans

-ex: mosquitos, ticks, fleas, triatomine bugs

vector-borne disease burden

highest in tropical and subtropical areas

mosquito-borne diseases

-Malaria (protozoan parasite)
-Zika virus
-West Nile virus

-Chikungunyavirus

dengue-Denguevirus
-Yellow Fever virus

dengue

-symptoms can be mild or severe

-eye pain, muscle pain, bone pain, joint pain, headache, rash, nausea and vomiting

-disease cause by a virus spread by mosquitos

severe dengue

after fever begins to drop, warning signs of severe dengue can appear (e.g., bleeding from nose or gums, vomiting blood, blood in stool, fatigue, irritability, belly pain)

tick-borne disease: rocky mountain spotted fever

-one of the deadliest tick-borne diseases in the US

-caused by bacterium Rickettsia rickettsii

-symptoms include fever, rash, and headache

tick-borne disease: lyme disease

-caused by bacterium Borrelia burgdorferi

can be treated with antibiotics

-symptoms: fever, headache, fatigue, skin rash

-can cause severe arthirits, or neruological or cardiac problems

neglected tropical diseases (NTDs)

-diseases that predominantly lower income populations; cause substantial morbidity & mortality

-all low-income countries are affected by multiple NTDs

-parasitic worms and protozoan parasites cause a number of important NTDs

schistosomiasis (NTD)

-infection through skin contact with the water

-symptoms: blood in urine or stool, anemia, problems with growth and development in children, bladder cancer, kidney and liver damage

-second to malaria but most deadly NTD

onchocerciasis (river blindness) NTD

-bites by blackflies (vector) that transmit parasitic worm

-symptoms: intense itching, disfiguring skin lesions, eye disease that can cause blindness

soil-transmitted helminths STH (NTD)

-through contact with soil contaminated with infected feces

-symptoms: anemia, vitamin A deficiency, malnutrition and impaired growth, delayed development, intestinal blockages

round worms- Acaris lumbricoides

-ingestion of eggs from contaminated soil

-often no symptoms, but can cause abdominal pain, intestinal blockage, and impair children’s growth

-worms migrate through body to lungs and cause coughing

hookworm- Necator americanus

-primarily by skin contact with soil contaminated with hookworm larvae (walking barefoot; can penetrate the skin of humans

-symptoms: itching and localized rash, fatigue, abdominal pain, diarrhea, loss of appetite, weight loss, anemia

-affect cognitive and physical growth

protozoans

-microscopic, one-celled organisms

-can be free-living

malaria

-transmitted by: bite of female anopheles mosquitos, in utero, blood transfusions, organ transplant, sharing needles

-symptoms: fever, flu-like, chills, headache, muscle aches, nausea, vomiting, diarrhea, anemia, jaundice

why is a malaria vaccine so difficult to make?

multiple different developmental stages and effective ways of avoiding immune response

chagas disease

-vector borne transmission by triatomine bug or kissing bug

-contact with the feces of an infected triatomine

toxoplasmosis

-infects most species of warmblooded animals, including humans

-transmission: undercooked contaminated meat, food or water contaminated by cat feces, contact with contaminated soil, blood transfusion

-parasite

giardia lamblia (waterborne pathogen)

transmission: ingestion of contaminated food or water and ingestion of pathogen from hands/fomites