Malaria Biology and Transmission

Study Notes

Caused by the parasite Plasmodium spp., a single-celled protozoan parasite
Six different species of Plasmodium can infect humans
Parasites also infect other animals, including primates, rodents, birds, lizards, and amphibians
People at risk include immunologically naive individuals, predominantly children under 5, and non-immune travelers
Life cycle involves two hosts: humans and mosquitoes
Only female mosquitoes transmit the parasite
Symptoms include acute malaria, fever, chills, anaemia, headache, diarrhoea, and vomiting
Diagnosis is made through patient history, rapid diagnostic test (RDT), and PCR
Effective antimalarials are available, but treatment outcomes can be problematic due to resistance, data in pregnancy, and counterfeit drugs

Insect repellent, bed nets, protective clothing, chemoprophylaxis, and mosquito control can prevent malaria
Two vaccines are available, targeting the sporozoite stage: RTS, S and R21/Matrix M

Causes cryptosporidiosis (crypto)
Symptoms include diarrhoea, abdominal pain, nausea, fever, and fatigue
Transmission occurs through the faecal-oral route, involving ingestion of oocysts in contaminated water
Life cycle has multiple stages, and the disease is generally self-limiting but can be serious in immunocompromised individuals
Diagnosis is made through stool sample analysis
Treatment involves drinking fluids to prevent dehydration, and anti-parasite drugs are available

Good hygiene practices, avoiding contaminated water sources, and boiling or filtering contaminated water can prevent cryptosporidiosis
No vaccines are currently available

Term used for all groups of parasitic worms
Multicellular organisms, including roundworms (nematodes) and flatworms (platyhelminths)
Roundworms have cylindrical bodies and lack specialized attachment organs
Flatworms have flat bodies, muscular suckers and/or hooks for attachment, and complex body organization

Multiple species of roundworms (nematodes)
Transmission: eggs hatch into larvae in the soil, penetrate the skin, and are carried to the lung and then to the small intestine
Symptoms include rash, itch at site of skin infection, mild diarrhoea, anaemia, abdominal pain, and loss of appetite and weight loss
Diagnosis is made through faecal analysis
Effective drugs are available, such as albendazole
Prevention involves avoiding contact with contaminated soil and improving hygiene and sanitation