Table 1 Predictive explanatory variables of malaria re-introduction and/or outbreaks by risk category
Risk assessment variables | Risk classification | ||
|---|---|---|---|
High | Moderate | Low | |
Parasite reservoirs | |||
Population movement of a target focus with endemic areas | Entrance of unpermitted immigrants from neighboring endemic countries to a target focus | Population of a target focus with a history of travelling to neighboring endemic countries | No population movement with endemic malaria areas |
Mean score | 5 | 3.99 | 0.01 |
Quality of population movement in a target focus | Entrance of unpermitted immigrants from neighboring endemic countries who have no protected settlements that make them exposed to mosquito biting | Population of a target focus with a history of travelling to endemic areas or entrance of unpermitted immigrants from these countries who have protected settlements | No population movement |
Mean score | 5 | 3.8 | 0.2 |
Proportion of immigrants from neighboring malaria endemic countries in a target focus who were examined for malaria during previous malaria transmission season | Less than 30 % | Between 31 and 60 % | More than 60 % |
Mean score | 4.7 | 4 | 0.3 |
Target focus classification | New active or residual active | New potential or residual non active | Cleared-up |
Mean score | 3.9 | 3.7 | 1.4 |
Having a history of malaria outbreaks in a target focus | History of malaria outbreaks during previous 12 months | History of malaria outbreaks during previous 13–36 months | No report of malaria outbreaks during previous 36 months |
Mean score | 4.1 | 3.3 | 1.6 |
Report of malaria cases (regardless epidemiological classification) in a target focus during previous 3 weeks | Malaria cases were reported every week during previous 3 weeks | Malaria cases were reported within only 1 or 2 weeks during previous 3 weeks | No reported malaria case |
Mean score | 5.1 | 2.9 | 1 |
Infrastructures, health services and common social behavior in a target focus | |||
Earliest possible time for a malaria surveillance team to have access to a target focus | The target focus is not accessible by motor vehicles within 7 days | The target focus is accessible between 2 and 7 days by motor vehicles | The target focus is accessible on the first day |
Mean score | 4.2 | 3.15 | 1.65 |
Earliest possible time for suspected malaria cases in a target focus to have access to malaria diagnosis and treatment services | Malaria diagnosis and treatment services are not accessible within 7 days | Malaria diagnosis and treatment services are accessible between 3 and 7 days | Malaria diagnosis and treatment services are accessible in less than 3 days |
Mean score | 4 | 3 | 2 |
Sleeping outdoors in a target focus | More than 80 % of people in the target focus have tendency to sleep outdoors | Between 41 and 79 % of people in the target focus have tendency to sleep outdoors | Less than 40 % of people in the target focus have tendency to sleep outdoors |
Mean score | 4 | 3.5 | 1.5 |
Electricity accessibility | Not accessible | Frequent power outage specially in the evenings and nights | Accessible 24/7 |
Mean score | 4 | 3.25 | 1.75 |
Meteorological variables | |||
Average daily maximum temperatures in previous 8 weeks | Between 30 and 42 ℃ | Between 26 and 30 ℃ or 42 and 44 ℃ | Less than 26 ℃ or more than 44 ℃ |
Mean score | 4.9 | 3.5 | 0.6 |
Average daily minimum temperatures in previous 8 weeks | Between 16 and 27.9 ℃ | Between 11.5 and 16 ℃ or 27.9 and 29.9 ℃ | Less than 11.4 ℃ or more than 30 ℃ |
Mean score | 5.1 | 3.55 | 0.35 |
Average daily relative humidity in the period of previous 4 weeks relative to its previous eight-weeks period | Any increase of more than 22 % | Any increase of more than 17 % and less than 21 % | Any increase of less than 16 % or no increase |
Mean score | 4.5 | 3.5 | 1 |
Total of rainfall during previous 8 weeks | More than 7 mm | Between 1 and 6 mm | No rainfall |
Mean score | 5 | 3 | 1 |
Vector variables | |||
Type of vectors in a target focusa | More than two main vector species | At least a main species of vector plus secondary species | Only secondary species |
Mean score | 4.75 | 3.25 | 1 |
Average time period that common breeding places are existed in a target focusb | More than 21 days | Between 8 and 20 days | Between 1 and 7 days |
Mean score | 4.2 | 3.25 | 1.55 |
Larvae density in a target focus based on randomly larvae collection method | Existence of third and fourth instar larvae and pupae, with majority of first and second instar | Existence of third and fourth instar larvae | No existence of larvae |
Mean score | 4.38 | 3.02 | 1.6 |
Outdoor resting shelter for malaria vectors in a target focusc | A big number of outdoor resting shelters | A few outdoor resting shelters | None |
Mean score | 5.25 | 3 | 0.75 |
Other variables | |||
Outbreaks of other diseases in the region during previous 3 months | Yes | No | Unknown |
Mean score | 4 | 3.5 | 1.5 |
Following malaria transmission season | From March to October | November or February | From December to January |
Mean score | 4.5 | 4 | 0.5 |