Routes of transmission

Mother to child

Perinatal

Congenital/vertical

Airborne/inhalational

Contact of skin/mucosa

Direct

Indirect

Ingestion

Ingestion of any food or water
contaminated with

Toxins

Parasite ova/cysts

Microorganisms

Insect/arthropod-borne injection through skin penetration

Mosquitoes and disease
transmission

Glossina spp

Simulium spp

Phlebotomus spp

Simulium spp

Aedes spp

Lice

Culicine spp

Fleas

Anopheles spp

Arachnids

Ticks

Mites

Insect feces rubbed into skin

Reduvid bugs Rhodnius spp

Inhalation of air, aerosol, fomite
contaminated by microbes

Direct penetration through skin

Helminth larvae

Fly larvae

Innoculation or injection

Breach of skin or mucous
membrane

Viruses

Fungal infections

Bacteria

Multiple modes of transmission

Direct contact

Insect bites

Insect bites and airborne

Skin/mucosa contact

Transplacental transmission
via blood

hepatitis viruses

Vaginal/cervical contact during
delivery

Bacterial

Contact via breast milk

Sexually transmitted diseases

Chlamydia spp

Sexually transmitted diseases

Boils

cholera

Staphylococcal

Infections caused by nematodes

Infections caused by nematodes

Arbovirus encephalitis

Yellow fever

Leishmaniasis

Sleeping sickness

Onchocerciases

Filariasis

Pediculosis

Plague Yersinia pestis

Chiggers

Lyme disease

Chagas disease

Helminth larvae penetration into subcutaneous tissue

Fly bots and warbles

Animal and human bites

Viruses

Hepatitis B

airborne
pneumonic plague

Anthrax

Malaria

HIV

Reference

Zumla, A., & Ustianowski, A. (2012). Tropical diseases: definition, geographic distribution,transmission, and classification. Infectious disease clinics of North America, 26(2),195–205. https://doi.org/10.1016/j.idc.2012.02.007