DEFINITIONS
WHO standard malaria case definitions
Probable malaria: a person with signs and/or symptoms of malaria and who receives antimalarial treatment.
Probable severe malaria: a person who requires hospitalization for signs and/or symptoms of severe malaria and receives antimalarial treatment.
Probable malaria death: death of a person who was diagnosed with probable severe malaria.
Confirmed malaria: a person with signs and/or symptoms of malaria, who receives antimalarial treatment, with laboratory confirmation of diagnosis.
Confirmed severe malaria: a person requiring hospitalization for signs and/or symptoms of severe malaria, who receives antimalarial treatment, with laboratory confirmation of diagnosis.
Confirmed malaria death: death of a person who was diagnosed with severe malaria, with laboratory confirmation of diagnosis.
Indigenous or autochtonous malaria case: a malaria case that is natural to an area or country, i.e. not imported. The term is applied to cases whose origin from local transmission cannot be disproved.
Imported malaria case: a malaria case in which the infection was acquired outside the area in which it is found, implying that its origin could be traced to a known malarious area.
Induced malaria case: a malaria case attributed to the effect of a blood transfusion or other form of parenteral inoculation, but not to normal transmission by the mosquito. The course of the infection might be different from that observed in the normal case.
Introduced malaria case: a malaria case in which it can be proved that the infection is the first step (direct secondary) of local transmission subsequent to a proved imported case.
Source: (15).
Other definitions
Epidemic: term applied to malaria when the incidence of cases—other than seasonal rises—in an area rises rapidly and markedly above its usual level or when the infection occurs in an area where it was not previously present. Malaria epidemics occur principally in areas of low transmission, where no single age group in the population is immune. The introduction of malaria, particularly if exacerbated by changes in rainfall and temperature, can trigger explosive epidemics that affect both adults and children. Epidemics can also occur in areas of higher transmission as the result of the abandonment of control programmes, immigration of non-immune people and reduced access to treatment.
Endemic: term applied to malaria when there is a constant measurable incidence both of cases and of natural transmission in an area over a succession of years.
Hypoendemic: term applied to malaria when transmission is of low intensity and usually not throughout the year andwhere the disease burden is generally low. In the classification of Metselaar & Van Thiel, hypoendemicity corresponds to a parasite infection prevalence below 10% in children 2–9 years of age (77).
Hyperendemic: term applied to malaria when transmission occurs usually throughout the year at high intensity and the disease burden is high in young children. In the classification of Metselaar & Van Thiel, hyperendemicity corresponds to a parasite infection prevalence above 75% in children 1 year of age (77).
