Question

What are the conditions that promote proliferation of parasitic protozoans?

Answer 1

            Protozoa are microscopic, one-celled organisms that can be free-living or parasitic in nature. A parasite may have more than host, where the carry on their life cycle. Availability of suitable and healthy host plays a great role in the proliferation of these parasites. Besides this when these parasites are out of the host’s body, environmental and physical factors like temperature, light, water quality, soil composition, humidity affects their proliferation. With a suitable environment these parasites multiply rapidly.

            Examole: They are able to multiply in humans, which contributes to their survival and also permits serious infections to develop from just a single organism. Transmission of protozoa that live in a human’s intestine to another human typically occurs through a fecal-oral route (for example, contaminated food or water or person-to-person contact). Protozoa that live in the blood or tissue of humans are transmitted to other humans by an arthropod vector (for example, through the bite of a mosquito or sand fly).

            The protozoa that are infectious to humans can be classified into four groups based on their mode of movement:

Sarcodina – the ameba, e.g., Entamoeba

Mastigophora – the flagellates, e.g., Giardia, Leishmania

Ciliophora – the ciliates, e.g., Balantidium

Sporozoa – organisms whose adult stage is not motile e.g., Plasmodium, Cryptosporidium