3.a. Communicable diseases have causes and impacts with mitigation and response strategies which have varying levels of success.

Question 1

What causes malaria?

(Case Study: Malaria in Ethiopia)

Answer 1

A tiny plasmodium parasite.

Question 2

The malaria plasmodium parasite has two hosts, what are they?

(Case Study: Malaria in Ethiopia)

Answer 2

The anopheles mosquitoes, and humans.

Question 3

Mosquitoes act as vectors, transmitting the disease from person to person. How does the parasite enter the body?

(Case Study: Malaria in Ethiopia)

Answer 3

Parasites enter people through the bite of an infected mosquito.

Question 4

In 2019, how many people died from malaria? What percentage were children under the age of 5 years?

(Case Study: Malaria in Ethiopia)

Answer 4

In 2019, malaria claimed 405,000 lives; 75% of deaths were children under the age of 5 years.

Question 5

Africa accounted for what percentage of malaria deaths in 2018?

(Case Study: Malaria in Ethiopia)

Answer 5

94%.

Question 6

What are the 4 human causes of malaria in Ethiopia?

(Human causes)
(Case Study: Malaria in Ethiopia)

Answer 6

Population movements, irrigation schemes, urbanisation, and the misuse of malarial drugs.

These all encourage the spread of the disease.

Question 7

Outline ‘population movements’ as a human cause of malaria in Ethiopia.

(Human causes)
(Case Study: Malaria in Ethiopia)

Answer 7

Annually at harvest and planting time, large-scale, seasonal population movements take place between the malaria-free central highlands and the agricultural western lowlands.

The timing of this migration coincides with the rainy season and the peak malarial transmission period, (June to September), in the lowlands.

Question 8

Outline ‘irrigation schemes’ as a human cause of malaria in Ethiopia.

(Human causes)
(Case Study: Malaria in Ethiopia)

Answer 8

Infection is also increased as harvesting often continues after sunset when mosquitoes are most active, and most migrant workers sleep in the fields overnight.

Irrigation projects in the Awash Valley and in Gambella province, and the cultivation of rice, have both expanded the breeding habits of mosquitoes.

Question 9

Outline ‘urbanisation’ as a human cause of malaria in Ethiopia.

(Human causes)
(Case Study: Malaria in Ethiopia)

Answer 9

Has had a similar effect to irrigation schemes, with flooded excavations, garbage dumps, discarded containers.

Thus, countless breeding sites are being provided.

Question 10

Outline ‘misuse of malarial drugs’ as a human cause of malaria in Ethiopia.

(Human causes)
(Case Study: Malaria in Ethiopia)

Answer 10

Malarial parasites are becoming increasingly drug-resistant and some experts point out that the last significant breakthroughs in anti-malarial drugs were made nearly 50 years ago.

Question 11

Most malarial mosquitoes thrive in what conditions? What influences habitats in Ethiopia?

(Environmental causes)
(Case Study: Malaria in Ethiopia)

Answer 11

Warm, humid climates; where stagnant surface water proves ideal breeding habitats for mosquitoes.

In Ethiopia, habitats are strongly influenced by altitude.

Question 12

Outline ‘Western Lowlands’ as an environmental cause of malaria in Ethiopia.

(Environmental causes)
(Case Study: Malaria in Ethiopia)

Answer 12

Temperatures and humidity are high throughout the year, thus the disease is endemic.

Question 13

Outline ‘Central Highlands’ as an environmental cause of malaria in Ethiopia.

(Environmental causes)
(Case Study: Malaria in Ethiopia)

Answer 13

The absence of malaria is explained by low average temperatures, which slow the development of mosquitoes and the plasmodium parasite.

Question 14

Malaria is endemic to what percentage of Ethiopia’s land area?

(Prevalence, incidence, and patterns)
(Case Study: Malaria in Ethiopia)

Answer 14

75% of land area.

Question 15

What fraction of the Ethiopia’s population live in areas at risk from the disease, which kills around 70,000 people a year?

(Prevalence, incidence, and patterns)
(Case Study: Malaria in Ethiopia)

Answer 15

2/3 of the country’s population.

Question 16

When do malaria transmission peak?

(Prevalence, incidence, and patterns)
(Case Study: Malaria in Ethiopia)

Answer 16

Transmission rates peak after the rainy season, (between June and November).

Question 17

Malaria is not evenly distributed in Ethiopia. Outline the distribution of malaria in the lowlands.

(Prevalence, incidence, and patterns)
(Case Study: Malaria in Ethiopia)

Answer 17

Areas of highest risk are the western lowlands (e.g. Tigray, Amhara).

In places such as Afar and Somali provinces, in the eastern lowlands, the arid climate confines malaria to river valleys.

Question 18

Malaria is not evenly distributed in Ethiopia. Outline the distribution of malaria in the midlands.

(Prevalence, incidence, and patterns)
(Case Study: Malaria in Ethiopia)

Answer 18

In the midlands, where altitude ranges from 1000m to 2200m, transmission is also seasonal, with occasional epidemics.

Question 19

Malaria is not evenly distributed in Ethiopia. Outline the distribution of malaria in the highlands.

(Prevalence, incidence, and patterns)
(Case Study: Malaria in Ethiopia)

Answer 19

The central highlands, comprising around 1/4 of the country, area malaria-free.

Question 20

Ethiopians suffer approximately how many episodes of malaria a year? How many are killed as a result?

(Socio-economic impacts)
(Case Study: Malaria in Ethiopia)

Answer 20

Ethiopians suffer approximately 5 million episodes of malaria a year, which kill around 70,000 people.

Question 21

Are socio-economic impacts significant? How and why?

(Socio-economic impacts)
(Case Study: Malaria in Ethiopia)

Answer 21

Yes, with poorest communities being hit hardest.

The poorest families often live in crudely built dwellings that offer few barriers to mosquitoes.

Question 22

Outline ‘employment’ as a factor affected by the presence of malaria in Ethiopia.

(Socio-economic impacts)
(Case Study: Malaria in Ethiopia)

Answer 22

Malaria causes severe effects such as absenteeism from work.

This slows economic growth and reinforces the cycle of poverty.

Lost production in sub-Saharan Africa due to malaria is estimated to be US$12 billion a year.

In Ethiopia, malaria absorbs 40% of national health expenditure, accounts for 10% of hospital admissions, and 12% of health clinic visits.

This is overwhelming, damaging tourism and curtailing inward investment.

Question 23

Outline ‘farming’ as a factor affected by the presence of malaria in Ethiopia.

(Socio-economic impacts)
(Case Study: Malaria in Ethiopia)

Answer 23

Malaria also has implications for food security and the environment.

The western lowlands, for example, are resource-rich, with considerable potential to raise food production.

But malaria, which is endemic to the region, holds back development.

This problem has a knock-on effect in the highlands, as this region is malaria-free, it supports unusually high population densities.

As a result, its meagre farming resources have been overexploited for generations, resulting in widespread land degradation.

This situation contributed to devastating famines in the 1980s.

Question 24

Malaria is a disease that can be treated, but…

(Direct and in-direct strategies used by government and international agencies to mitigate against the disease and respond to outbreaks)
(Case Study: Malaria in Ethiopia)

Answer 24

Malaria is a disease that can be treated, but not always cured.

Question 25

Drugs used in malaria prevention and treatment have side-effects, both physical and psychological. Give an example. (Direct and in-direct strategies used by government and international agencies to mitigate against the disease and respond to outbreaks) (Case Study: Malaria in Ethiopia)

Answer 25

Chloroquine. Has long been used to treat malaria by causing the pH in certain parts of the parasite's cell to increase, preventing important biochemical reactions.

Question 26

What are the two dominant malaria parasites in Ethiopia? What percentage of cases are each responsible for? (Direct and in-direct strategies used by government and international agencies to mitigate against the disease and respond to outbreaks) (Case Study: Malaria in Ethiopia)

Answer 26

P. falciparum (60% of cases). P. vivax (40% of malaria cases).

Question 27

The national malaria guidelines recommend what for the treatment of P. falciparum? (Direct and in-direct strategies used by government and international agencies to mitigate against the disease and respond to outbreaks) (Case Study: Malaria in Ethiopia)

Answer 27

Artemisinin-based combination therapies (ACTs) for the treatment of uncomplicated malaria caused by P. falciparum.

Question 28

The national malaria guidelines recommend what for the treatment of P. vivax? (Direct and in-direct strategies used by government and international agencies to mitigate against the disease and respond to outbreaks) (Case Study: Malaria in Ethiopia)

Answer 28

Chloroquine: most efficient treatment in malaria-endemic areas.

Question 29

The prevention and control programme in Ethiopia is outlined in what? (Direct and in-direct strategies used by government and international agencies to mitigate against the disease and respond to outbreaks) (Case Study: Malaria in Ethiopia)

Answer 29

National Malaria Strategic Plan (NMSP) in line with the WHO's global campaign to Roll Back Malaria (RBM).

Question 30

The current methods of controlling malaria interventions implemented in Ethiopia include what 3 methods? (Direct and in-direct strategies used by government and international agencies to mitigate against the disease and respond to outbreaks) (Case Study: Malaria in Ethiopia)

Answer 30

- Insecticide-treated mosquito nets (ITNS). - Indoor residual spraying (IRS). - Mosquito larval source reduction.

Question 31

What did the malaria indicator survey (MIS) show in 2015? (Direct and in-direct strategies used by government and international agencies to mitigate against the disease and respond to outbreaks) (Case Study: Malaria in Ethiopia)

Answer 31

That more than 70% of households in malaria-endemic areas were protected by either ITN or IRS. However, the rate of improved household protection has slowed down in the past few years.

Question 32

Ethiopia has recently targeted malaria elimination nationwide in 2030, aligned with what? What has this done? (Direct and in-direct strategies used by government and international agencies to mitigate against the disease and respond to outbreaks) (Case Study: Malaria in Ethiopia)

Answer 32

The WHO's Global Technical Strategy (GTS) - intensifying the existing malaria control activities.

Question 33

In 2019, Ethiopia was on track to achieve the 2020 milestone by reducing the incidence of malaria by what percent? (Direct and in-direct strategies used by government and international agencies to mitigate against the disease and respond to outbreaks) (Case Study: Malaria in Ethiopia)

Answer 33

40%.

Question 34

What are the challenging factors for malaria elimination in Ethiopia and globally? (Direct and in-direct strategies used by government and international agencies to mitigate against the disease and respond to outbreaks) (Case Study: Malaria in Ethiopia)

Answer 34

- The emergence of insecticide resistance. - Migrant populations. - Emerging chloroquine resistance for P. vivax. - The difficulty in both controlling and eliminating P. vivax.