41.2 Priority diseases for IDSR in Ethiopia
Priority diseases are diseases that fulfil one or more of the criteria in Box 41.1.
Box 41.1 Priority disease criteria
- They have a high potential for causing epidemics
- They have been targeted for eradication or elimination
- They have significant public health importance (causing many illnesses and deaths)
- They can be effectively controlled and prevented.
Currently, there are 20 reportable priority diseases or conditions in Ethiopia, which are included in the IDSR system (Table 41.1). As the table shows, these 20 priority diseases are further classified into ‘immediately’ or ‘weekly’ reportable diseases. Some of the priority diseases, such as avian influenza, pandemic influenza A, cholera, measles, meningitis and relapsing fever are likely to spread quickly and to affect a large number of people. Therefore, you should always be alert for such diseases in your community, and report immediately to a health centre if you suspect, or are unsure about, a case.
| I. Immediately reportable diseases (report within 30 minutes to higher authority) | Description of the disease | |
|---|---|---|
| 1 | Acute flaccid paralysis (AFP) | Polio is the major cause of AFP (see Study Session 4 of this Module) |
| 2 | Anthrax | An acute bacterial disease, transmitted from animals to humans (zoonosis), manifested by skin lesions and (rarely) respiratory symptoms, e.g. shortness of breath |
| 3 | Avian human influenza | An acute viral disease of the respiratory tract, transmitted from birds to humans, characterised by fever, headache, muscle pain, prostration, runny nose and other symptoms of head cold, sore throat and cough |
| 4 | Cholera | Bacterial disease that causes profuse, watery diarrhoea (see Study Session 34) |
| 5 | Dracunculiasis/ Guinea worm disease | An infection of the deep part of the skin by a worm, manifested by blister formation and discharge of the worm when the affected leg of the patient is immersed into water |
| 6 | Measles | A viral disease manifested by a whole-body rash, cough and sore eyes (see Study Session 4) |
| 7 | Neonatal tetanus | A rapidly fatal bacterial disease of newborns manifested by neck stiffness, convulsions, sensitivity to bright light and inability to feed due to locked jaw (see Study Session 3) |
| 8 | Pandemic influenza A (H1N1) | An acute viral disease of the respiratory tract, transmitted from animals to humans, characterised by fever, headache, muscle pain, prostration, runny nose and other symptoms of head cold, sore throat and cough |
| 9 | Rabies | A viral disease affecting the nervous system, transmitted by the bite of a rabid dog (see Study Session 38) |
| 10 | Severe acute respiratory syndrome (SARS) | A rapidly fatal severe viral respiratory infection associated with gastro-intestinal symptoms such as diarrhoea |
| 11 | Smallpox | A viral disease manifested by a rash (but this disease has been eradicated from the world) |
| 12 | Viral haemorrhagic fever (VHF) | An acute viral disease manifested by fever, muscle pain and bleeding |
| 13 | Yellow fever | An acute viral disease of short duration, transmitted by mosquitoes, manifested by fever, muscle pain and headache |
| II. Weekly reportable diseases | ||
| 14 | Dysentery | A bacterial or amoebic disease manifested by bloody diarrhoea (see Study Sessions 33 and 34) |
| 15 | Malaria | An acute febrile disease with chills, headaches and muscle pain, caused by plasmodium parasites transmitted by mosquitoes (see Study Sessions 5 to 12) |
| 16 | Malnutrition | A condition caused by shortage of protein, or carbohydrate or vitamins or minerals |
| 17 | Meningitis | A bacterial disease manifested by fever and stiffness of the neck (see Study Session 3) |
| 18 | Relapsing fever | A bacterial disease, transmitted by human body lice, manifested by episodes of fever, headache and muscle/joint pain (see Study Session 36) |
| 19 | Typhoid fever | A bacterial disease manifested by fever, headache, joint pain and diarrhoea (see Study Session 33) |
| 20 | Typhus | A bacterial disease, transmitted by human body lice, manifested by sustained high fever, headache and muscle/joint pain (see Study Session 36) |
What is the difference between eradication and elimination? (Think back to Study Session 2 of this Module).
Elimination is reduction to zero (or a target very close to zero) of cases of a particular communicable disease in a particular geographic area. Eradication is the elimination of a communicable disease from the whole world. Polio, guineaworm disease and neonatal tetanus have been targeted for global eradication by the World Health Organization (WHO).
In addition to the reportable diseases and conditions listed in Table 41.1, you should report the health emergencies or emergency conditions listed in Box 41.2. The term cluster refers to a larger-than-expected number of cases with similar symptoms, but without clear evidence (at this time) that they are connected in any way. The increase in cases in a cluster could simply be a coincidence, but it could also be a sign that an epidemic is beginning, i.e. the rise in number is due to transmission of the infectious agents between cases. That is why you should report the conditions in Box 41.2 immediately.
Box 41.2 Health emergencies or conditions to report immediately
- Clusters of respiratory illness (including upper or lower respiratory tract infections and difficulty in breathing)
- Clusters of gastrointestinal illness (including vomiting, diarrhoea, abdominal pain, or any other gastrointestinal distress)
- Influenza-like symptoms and signs, such as fever, cough and runny nose
- Clusters of symptoms or signs indicating the possibility of meningitis (stiff neck, sensitivity to bright light, severe headache, etc.)
- Clusters of rash-like symptoms
- Non-traumatic coma (unconsciousness which is not due to an injury), or sudden death.
41.1 Importance of the Integrated Disease Surveillance and Response (IDSR) system