Question

4) How did the development of agriculture impact the transmission of infectious disease?

Answer 1

Impact of agriculture on transmission of infectious disease:

As the population increases, demand on the food also increases. So we need to develop the new agriculture lands to increase the production.

Development in agriculture also has increase in adverse health effect.

Increase in spread of vector borne diseases in these new areas and increase in transmission rate.

Malaria, lymphatic filariasis, yellow fever, leishmaniasis are some of the disease whose transmission is increased due to agricultural development.

How agriculture development have impact on health:

There are several factors that determine the health risk associated with agriculture they are

1. Environmental
2. Ecological
3. Demographic
4. Socio-economic changes

Environment and Ecological changes:

The agriculture development has created new sites for the vectors to develop.

• Predator species for these vectors are absent and so the conditions favour the vector longevity.
• Vector has limited breeding site requirements. Development in agriculture will pay way for the vectors to adapt to wide range of breeding sites.
• Vector longevity increases means, the life span of adult vector increases. Example: mosquito when the life span of adult mosquito increases, they will continue to feed on high blood meal and increase the transmission of disease.
• Irrigation in the field increase the humidity in the area which also increase the vector longevity.
• Water storage in dams for irrigation purpose has suitable habitat for aquatic snail.
• Snail is the intermediate host for schistosome parasites.
• When children swim in the water or agriculture workers wash themselves the parasite can enter the human and cause schistosomiasis
• Use of domestic animals also increase the intermediate host availability and increase the transmission of disease.

Demographic changes:

Agriculture development is associated with demographic change.

• It leads to large populations to be exposed to infections via peak vector borne disease occurs.
• Temporary workers may come to the site for the purpose of agriculture; these people will not have proper immunity. So it’s easy for them to get affected, sometime it even leads to death.
• Temporary workers who visit too and fro also increase the transmission of disease in other areas.

Socio-economic changes:

Socio economic changes are usually positive due to agriculture development. Because of agriculture development improvement in the community level takes place.

Increase in socio-economic behaviour of humans also increases the transfer of the infectious disease.