All UK Exam Boards included


Problems of controlling endemic diseases

Malaria is endemic to a wide stretch around the equator that covers South and Central America, Africa, the Middle East and South-East Asia. A disease is endemic when it occurs routinely in an area. An epidemic, on the other hand, is a temporary explosion of cases of a disease in an area.

Numbers of people surpassing 100,000,000 are newly infected yearly, with hundreds of thousands dying as a result. There are three conditions conductive to malaria being endemic, and that determine which efforts to curb the disease are most likely to bear fruit in a particular region:

1. High human density
2. High anopheles mosquito density
3. High rates of transmission from mosquitoes to humans and from humans to mosquitoes (as you remember, the gametophytes of the Plasmodium parasite fuse inside the mosquito to create sporozoites; these are transmitted to humans and undergo further development to produce gametophytes again, which get transmitted back to mosquitoes)

Economically speaking, it may be more worthwhile to prevent the disease than to treat it. This is feasible in areas like China where the money needed by the affected Chinese provinces to execute this is a small percentage of the healthcare budget, but not necessarily in other parts of the world affected by malaria, such as Tanzania, where these measures would by comparison be equivalent to a large portion of the budget (a fifth).

Social and enconomic infrastructures determine the outcome of infection, as treatment with antimalarials depends on the progression of the disease and the state of the patient. A vaccine is not in use yet, but trials are undergoing for a vaccine that could confer tolerance to the parasite (as opposed to immunity).

Under complete medical supervision and early treatment of an infected individual in the UK (acquired from an endemic region, as Plasmodium is not present in Europe; it can’t reproduce in the anopheles mosquito below 20 degrees Celsius), recovery is virtually guaranteed. Travellers can start treatment prior to travel or infection as a means of prevention, and use mosquito repelling substances. Both these approaches might not be available or practical to someone living in an endemic area, and within an area there might be people of different socio-economic status with different options or none at all regarding treatment and prevention.

Mass efforts to address this include low cost measures such as nets repelling to mosquitoes, and awareness of the symptoms of the disease and its transmission. Female mosquitoes bite at dusk and at night, and covering skin can minimise the risk of getting bitten.

Ethical issues exist surrounding the different control methods, as well as the process of the scientific community‘s validation of their efficacy. Enough evidence must support the use of a certain practice, especially if it is a drug or something that could make matters worse. Administering untested drugs to patients that are unable to consent, such as children, who are often more susceptible to malaria and can suffer from anaemia worse as a result of the infection, is an ethical issue.

Political ethical issues exist in the process of researching new treatments and prevention methods, and deciding whether enough evidence supports their deployment in various parts of the world. For example, this happened between the WHO (World Health Organisation) and the IPTi Consortium (funded by the Bill & Melinda Gates Foundation). IPT stands for intermittent preventative therapy, and involves administering various drugs to infants alongside their other vaccinations, every several months soon after birth.

It has shown great promise, with several studies confirming its efficacy at preventing malaria even after the drugs have left the body, and at better outcomes of anaemia. However, there are some contradictory or inconclusive studies, and the WHO decided that there was not enough evidence to start IPT in children in sub-Saharan Africa. There are multiple drugs available for IPT, with different and potentially unknown effects, as well as the risk of increasing drug resistance of the Plasmodium parasite through excessive use of certain drugs.

Eventually the WHO malaria chief, Dr. Akira Kochi, was replaced by a member of the IPTi Consortium. This resulted in the go-ahead given to administer IPT to children in high-transmission areas where resistance to the drugs used was low.

Ok byeeeeeeeee





Off-Spec Bonus Topics
Filter by
Post Page
Sort by

Sorry! There are no posts.

Sorry! There are no posts.

Our Reviews

I’ve struggled so much with feeling overwhelmed with biology revision, and I don’t know where to start. But your website is just what I need! It tells me all the information I need, and the knowledge I need to then build on, and it’s written in a way that soaks straight up into my brain!

Prettyhetty The Student Room

Just a huge thank you for spending your time helping others. I love your site and I'm seriously very grateful. No word of a lie

Neuron13 The Student Room

OMG them videos are great! You're a goldmine - and I'm a gold digger ;)

sc12 YouTube

Thank you!! Your site is so helpful!

studyaspect YouTube

OFF TOPIC : I just want to say that your website is brilliant, thank you!!

Anonymous YouTube