1. What is the difference between?
a. Commenslalism and parasitism
b. Obligate and temporary parasite
c. Definitive and intermediate host
d. Biological vector and mechanical vector
2. List the sources of exposure to parasite.
3. Mention possible parasites that are found in the following specimens
a. Stool
b. Blood
c. Urine
d. Sputum
e. CSF
4. Identify the possible sources of specimen for the following parasites
a. Schistosoma mansoni
b. E. vermicularis
c. Trypanosome species
d. Filaria worms
e. Giardia lamblia
5. Parasites that have indirect life cycle are more difficult to control.
Why?
1. Here is the difference between the given terms:
a. Commensalism and parasitism: Commensalism is a symbiotic relationship where one organism benefits and the other is neither harmed nor benefited. Parasitism, on the other hand, is a relationship where one organism (parasite) benefits at the expense of the other organism (host), causing harm or damage.
b. Obligate and temporary parasite: Obligate parasites are organisms that are completely dependent on a host for survival and reproduction, and cannot survive without a host. Temporary parasites, also known as facultative parasites, are organisms that can live independently but may infrequently parasitize a host for a short period of time.
c. Definitive and intermediate host: In parasitic life cycles, definitive hosts are the hosts where the parasite reaches its mature form and sexual reproduction occurs. Intermediate hosts, on the other hand, are hosts where the parasite undergoes one or more developmental stages but does not reach sexual maturity.
d. Biological vector and mechanical vector: A biological vector is an organism, typically an arthropod, that is essential for the transmission of a parasite's life stages or infectious agents. The parasite undergoes development or multiplication within the vector. A mechanical vector, on the other hand, is an organism that can mechanically transmit a parasite from one host to another without any development or multiplication of the parasite within itself.
2. Sources of exposure to parasites can include:
- Contaminated water sources
- Contaminated food (undercooked or improperly handled)
- Direct contact with infected individuals (through skin, sexual contact, etc.)
- Insect or animal bites
- Poor hygiene practices (not washing hands, not cleaning living spaces, etc.)
- Consumption of raw or undercooked animal products (meat, fish, etc.)
- Exposure to contaminated soil or feces
3. Possible parasites found in the following specimens:
a. Stool: Enterobius vermicularis (pinworm), Giardia lamblia, Cryptosporidium spp., Entamoeba histolytica, Ascaris lumbricoides (roundworms), and many more.
b. Blood: Plasmodium spp. (malaria parasites), Trypanosoma spp., Babesia spp., Leishmania spp., and others depending on the geographical location and the specific tests conducted.
c. Urine: Schistosoma spp., which can cause schistosomiasis (blood flukes), and some other parasite infections depending on specific circumstances or diagnostic tests conducted.
d. Sputum: Paragonimus spp. (lung flukes), Ascaris spp., Strongyloides spp., and others depending on the specific diagnostic tests conducted and underlying respiratory conditions.
e. CSF (Cerebrospinal fluid): Toxoplasma gondii, Naegleria fowleri, Cryptococcus neoformans, and other pathogens that can cause various forms of meningitis or encephalitis.
4. Possible sources of specimen for the following parasites:
a. Schistosoma mansoni: Stool or biopsy of colon tissue if available.
b. Enterobius vermicularis: Stool or scotch tape method around the perianal region.
c. Trypanosome species: Blood, lymph node aspirate, or cerebrospinal fluid (CSF) depending on the suspected stage or species.
d. Filaria worms: Blood (usually obtained during nocturnal periods when the microfilariae are more likely to be circulating). Depending on the species, other specimens such as skin snips, lymph node aspirates, or even urine may be required for diagnosis.
e. Giardia lamblia: Stool sample.
5. Parasites with an indirect life cycle are more difficult to control because they typically involve multiple stages and hosts. This complexity makes it harder to target all stages of the lifecycle with preventive measures. The transmission of indirect life cycle parasites often relies on a combination of vectors, intermediate hosts, and environmental factors, making it more challenging to interrupt the transmission cycle through targeted interventions. Additionally, the presence of reservoir hosts can further complicate control efforts, as these hosts may harbor and continue to spread the parasites to susceptible hosts.
characteristic of protozoan
Characteristics of protozoa (protozoans) include:
1. Unicellular Organisms: Protozoa are single-celled organisms, meaning they consist of only one cell.
2. Eukaryotic Cells: Protozoa have eukaryotic cells, which means their cells contain a nucleus and other membrane-bound organelles.
3. Heterotrophic: Protozoa are heterotrophic organisms, meaning they obtain their nutrients by ingesting or absorbing organic matter from their environment.
4. Mobility: Many protozoa are motile and possess various locomotion methods, such as flagella, cilia, pseudopodia (extensions of the cell membrane), or the ability to glide.
5. Reproduction: Protozoa exhibit various modes of reproduction, including asexual reproduction (such as binary fission, multiple fission, or budding) and sexual reproduction (such as conjugation).
6. Ecological Diversity: Protozoa are found in diverse habitats, including freshwater, marine environments, soil, and the bodies of plants and animals.
7. Parasitic or Free-living: Protozoa can be either parasitic, living in or on other organisms and causing diseases, or free-living, existing independently in their environment.
8. Important Roles: Protozoa play crucial ecological roles, such as being decomposers, contributing to nutrient cycling, and being part of the food chain as primary consumers.
9. Ability to Form Cysts: Some protozoa can form cysts, which are dormant, resistant stages that help them survive in unfavorable conditions and transmit between hosts.
10. Disease-Causing Potential: Certain protozoa can cause diseases in humans and animals, such as malaria (Plasmodium), amoebic dysentery (Entamoeba histolytica), sleeping sickness (Trypanosoma), and giardiasis (Giardia lamblia).
classification of protozoan
Protozoa (protozoans) are classified into various groups based on their characteristics and features. The classification of protozoa can be complex and has evolved over time. Currently, the most common classification system divides protozoa into the following phyla:
1. Phylum Sarcomastigophora: This phylum includes protozoa that possess flagella or pseudopodia for locomotion. It is further subdivided into the following classes:
- Class Phytomastigophorea: Flagellated protozoa that are primarily photosynthetic.
- Class Zoomastigophorea: Flagellated protozoa that are primarily heterotrophic and include parasites like Trypanosoma and Leishmania.
2. Phylum Ciliophora: This phylum includes protozoa that possess cilia for locomotion. They are characterized by the presence of numerous hair-like projections called cilia covering their surface.
3. Phylum Apicomplexa: This phylum includes parasitic protozoa that are characterized by the presence of an apical complex, which is involved in host cell penetration. Examples include Plasmodium (causative agent of malaria) and Toxoplasma (causative agent of toxoplasmosis).
4. Phylum Microspora: This phylum includes intracellular parasites that lack mitochondria and possess a unique organelle called a polar tube. Microsporidia mainly infect invertebrates, but some species can cause diseases in humans.
5. Phylum Amoebozoa: This phylum includes amoeboid protozoa that move using pseudopodia. They are characterized by their ability to change shape through the extension and retraction of cytoplasmic extensions. Examples include Entamoeba histolytica (causative agent of amoebic dysentery) and Acanthamoeba.
It is important to note that some classification systems may include additional phyla or modify the existing classifications based on new scientific discoveries and understanding of the evolutionary relationships between protozoa.