الفهرس 
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Abstract
Introduction: Malaria has been a major challenge to both public health and socioeconomic development particularly, in countries of Sub-Saharan Africa. Malaria is endemic throughout Sudan and the risk of malaria transmission varies from 1% to 74% based on climate conditions, leading to cause morbidity and mortality in Sudan. The annual estimated number is about 7.5 million cases and 35,000 deaths every year in Sudan. The nature of the topography, agricultural activities, and variations in climatic conditions indicate the long history of malaria in Sudan.
Economic evaluations and knowledge that play role in disease transmission at different locations and pattern of disease transmission that provide the decision-makers with quantitative information on how to allocate the scarce resources available for health investment. One goal of this study is to estimate the costs and effectiveness of four different malaria vector control activities namely are IRS, LLIBN, LC and EM in Sudan.
Objective:This study was carried out to monitor and evaluate different malaria vector control activities namely IRS, LLIBN, LC, and EM, in Sudan, through measuring entomological parameters (malaria transmission), epidemiological measure (annual malaria incidence) and costs (cost per person protected a year) for all investigated activities.
Methods: This study was conducted in 8 villages/districts in three localities (South Elgezira, Madani and Alfaw) belong to two states (Al Gezira and Al Gadarif) in Sudan. Two villages/districts for each activity were randomly chosen. The inputs utilized and the operational achievements of the applied malaria vector control activities and their costs were obtained from data of the National Malaria Control Program during 2017.
Cross-sectional entomological survey for adult and larvae of mosquitos were carried out during the rainy season (August to October 2017) for three days a month. Pyrethrum Spray Catch (PSC), Human Baited CDC Light Trapa Collection (LTC), and Exit Window Traps (EWT) for adult collection, and dipping method for collection of mosquito larvae were used. Identification of Anopheles species was done using morphological keys (Gillies and Coetzee, 1987) under a compound microscope. Moreover, adult specimens of Anopheles gambiae complex were identified by species-specific polymerase chain reaction (PCR) test for sibling species detection. Females Anopheles mosquitos were categorized according to the abdominal condition under a dissecting microscope to unfed (UF), freshly fed (FF), half gravid (HG) and gravid (GR). The entomological parameters including, Indoor resting density (IRD), Man-biting rate (MBR), Human blood index (HBI), Sporozoite rate (SP), Entomological inoculation rate (EIR), Party rate (PR), Longevity (Long), Sporogony cycle (N) and Vectorial capacity (VC) were calculated according to (WHO, 2013, Beier, 2002, WHO, 1975, Davidson,1954, MacDonald, 1957, Garrett-Jones & Shidrawi, 1969, Detinova, 1962, and christophers 1911)
Malaria incidence for 12 months in 2017, was obtained from the documents of health centers for each village/district. The head family person from each randamly selected house for the entomological survey was interviewed in order to assess the knowledge, attitudes, practices and nocturnal behavior of people related to malaria transmission. Also to asses possibility of treatment, prevention, and control of malria according to opinion of residents. The information was obtained using a questionnaire previously used in alike studies. The metrological data including temperature, relative humidity, wind speed and amount of rain in the study areas was obtained from the Sudanese Metrological Authorities (SMA).
Result:
The inputs utilized and operational achievements and their costs of four different malaria vector control activities:
Coverage of operations was arranged as follows, 97%, 95.2%, 50% and 20% in IRS, LLIBN, LC and EM respectively.
Generally, LLIBN and IRS activities remain more attractive health options in a rural areas of low-income country. LLIBN is the most cost-effective activity with a total cost per person/year ($ 0.85) and IRS was more expensive with a total cost per person/year ($ 1.6). The LC and EM activities were significantly lower in cost per person/year ($ 0.33 and $ 0.57 respectively) but significantly less effective and considered less cost-effective than LLIBN and IRS activities.
Entomological parameters of Anopheles mosquitos in study areas implemented four different malaria vector control activities:
Species composition
Species composition of mosquitos in the study areas showed that 6,418 insects (66.3%) is An. gambiae complex, 13 insects (0.1%) An. phronesis, 154 insects (1.6%) An.rufipes and 3094 insects (32%) Culex sp, after (PCR) test for An. gambiae complex it is found that (66%) of them An. arabiensis.
The density of Anopheles mosquito larvae, expressed as larvae/dip, reported during the rainy season in different study areas was 5.7 , 7.4, 8.9 and 10.9 in LLIBN ,IRS, EM, and LC activity implemetnted areas respectively.
Entomological parameters of malaria transmission
The highest IRD (19.3 female mosquitos/house) was recorded in EM activity implemented areas and the lowest (4.7 female mosquitos/house) for LC activity. The IRD were 4.77 in LC, 5.4 in LLIBN, 9.8 in IRS and 19.308 in EM implemented areas.
The highest MBR (0.458 bites person/night) was recorded in EM activity implemented areas and the lowest and the lowest (0.118 bites person/night) for LLIBN activity. The MBR were 0.118 in LLIBN, 0.247 in LC, 0.332 in IRS and 0.458 in EM implemented areas.
The highest of An. gambiae complex females 26 days was recorded in EM activity implemented areas and the lowest 12 days for IRS activity.
Ascending order of the parity rate and the longevity were (PR: 0.76 and long: 12 days in IRS), (PR: 0.80 and long: 14 days in LLIBN), (PR: 0.85 and long: 19days in LC) and (PR: 0.86 and long: 26 days in EM).
The overall Sporozoite rate (SP) a total 720 females of Anopheles were examined under a microscope after staining by Gemsa stain the average of sporozoite rate obtained is (1/ 720), 0.138 for An. gambiae complex, and no sporozoite are found for An. rufipes and An. pharoensis in the all study areas.
The highest EIR (0.0757 infectious bite/person) was recorded in EM activity implemented areas and the lowest (0.0163 infectious bite/person) for LLIBN activity. The EIR were 0.0163 in LLIBN, 0.0341 in LC, 0.0458 in IRS and 0.0757 in EM implemented areas.
The mean of the duration of the Sporogony cycle (N) found is (9.1) days in LLIBN and (8.43) days in each of the IRS, LC and EM activities.
The overall Human blood index (HBI), estimated was (0.6) for An. gambiae complex, and nil result is for An. rufipes and An. pharoensis in the all study areas.
The lowest VC (0.097) was recorded in LLIBN activity implemented areas indicating that the LLIBN activity has produced a positive effect on the malaria vectors in these study areas and the highest VC (0.650) for EM activity, indicating that the EM activity has produced least effect on malaria vectors in these study areas. The VC were 0.097 in LLIBN, 0.248 in IRS, 0.294 in LC and 0.650 in EM.
The biting peaks of Anopheles mosquitos indoors occur is found to be in the late night at (2 am to 4 am) in IRS, LC, EM and (12 am to 2 am) in LLIBN.
The biting peaks of Anopheles mosquitos outdoors in the late night (12 am to 2 am) for IRS and LLIBN while for EM is (2 am to 4 am)
The mean values of temperature are (27.20 0C in IRS, 28.20 0C in LLIBN, 27.10 0C in LC and EM), while mean of relative humidity values are (63.3% in IRS, 62% in LLIBN, 63.2% in LC and EM). The recorded mean value of wind speed is (2 Km/h in IRS, LC and EM and 2.1 Km/h in LLIBN), where the total amounts of rain/mm/year are (253.6 mm in IRS, 375 mm in LLIBNs and 413.9 mm in LC and EM).
The annual malaria incidence in the study areas showed significant variation between the different activities (3.20%, 4.77%, 13.12%, and 21.1%) for IRS, LLIBN, LC, and EM respectively.
Knowledge attitude and practice on malaria transmission, treatment and control
Almost all respondents considered mosquito, is the vectors responsible for transmission of malaria.
About half of respondants, mentioned that, mosquito bites, is the important problem in the area.
The majority of respondents (69.5% for IRS, 78.5% for LLIBN, 76%for LC and 75.5% for EM) as sleep indoors.
About half of the respondents (49.4%) in the all study areas use personal protection measures by using a repellent (lotion).
All the respondents recognized malaria as a serious health hazard and they mentioned that they would seek treatment within 24 hours of the onset of malaria symptoms (fever).
The majority of the respondents showed willingness to participate in community-based control measures, and source reduction which indicates their good knowledge for the elimination of mosquitos breeding sites.
Almost all respondents (98%) in all study areas willingness to pay money for implementing the malaria vector control activities.
The majority (78%) of respondents have a positive judgment towards LLIBN activity. On the other side, (60%) and (50%) of the respondents have a negative judgment towards IRS and EM, respectively.
Effect of nocturnal human behavior on malaria transmission
The majority of respondents in the study areas were always outdoors between 6pm hrs and 10pm hrs and they were indoor between 10pm hrs to 5am hrs.
Most of the children below 5 age, and women were indoors from 6pm to 6am.
Most of men were outdoor from 6 pm h to 10 pm h mainly for entertainment.
In summary, The LLIBN activity is found to be the most cost-effective as compared with other activities. Only, A. gambiae complex (mostly A. arabiensis) incriminated as a malaria vector in all study areas during the study period. The meteorological data considered optimal for malaria transmission all the year long but breeding sites were prevailing during the rainy season from August to October. The KAP survey showed the high knowledge and awareness of the people for malaria as a health problem in their community and showed high willingness to participate and help to implement vector control activities in all study areas.
6.2 Conclusion
1. Almost all vector control operations were monitored.
2. Coverage of operations was arranged as follows, 97%, 95.2%, 50% and 20% in IRS, LLIBN, LC and EM respectively.
3. The total financial cost and cost per person/year was $12,494 and $ 1.6 in IRS, $12,011 and $0.58 in LLIBN, $6,363 and $0.33 in LC and $2, 374 and $0.57 in EM.
4. Species composition of mosquitos in the study areas was An. gambiae complex 6,418 adults (66.3%) , An. phronesis 13 adults (0.1%), An. rufipes 154 adults (1.6%) and Culex spp 3094 adults (32%).
5. An. arabiensis was the only member of An. gambiae complex found.
6. An. gambiae complex (mostly An. arabiensis) is the only incriminated species of malaria vector in the all study areas during the study period (2017).
7. Indoor resting density (IRD) of An. gambiae complex (mostly An. arabiensis) valued 4.7, 5.4, 9.8, and 19.3 mosquito/room/night for LC, LLIBN, IRS and EM respectively, and there is a statistical significant difference (p≤ 0.022) among the four activities.
8. The entomological inoculation rate (EIR) of An. gambiae complex (mostly An. arabiensis) valued 0.016, 0.034, 0.045, and 0.075 infectious bites per person for LLIBN, LC, IRS and EM respectively.
9. The vectorial capacity (VC) of An. gambiae complex (mostly An. arabiensis) valued (0.097, 0.24, 0.29, 0.65) for LLIBN, IRS, LC and EM respectively, and there was a statistically significant difference (p≤ 0.034) among the four different tested vector control activities.
10. Anophelene mosquito larvae (11,819) were more prevalent culex larvae (8,250) in the all study areas.
11. The peak of indoor biting was at 2am to 4am in IRS, LC, EM and 10pm to 12 am in LLIBN implemetnted areas.
12. The peak of outdoor biting was 12am to 2am in IRS, and 10pm to 12 am in LLIBN, 4am to 6am in LC and 2am to 4am in EM implemented areas.
13. The annual malaria incidence in the study areas implemented different malaria vector control activities was (3.20%, 4.77%, 13.12%, and 21.1%) in LLIBN, IRS LC, and EM respectively.
14. These was correlation between vectorial capacity and malaria incidence.
15. The sporogony of P. falciparumr was very sensitive to temperature ranging from (8 to 9 days) at 27 Cº to 28 Cº respectively.
16. The KAP survey showed that the knowledge and awareness of majority of respondents about that “malaria is a problem” is high.
17. The respondents recognized between mosquito bites and malaria transmission.
18. High proportion of respondents stated that they would seek treatment within 24 hours of onset of malaria symptoms (fever), which indicates high awareness.
19. Mostly all respondents showed willingness to participate and help to implement the vector control activities in all study areas.
6.3 Recommendation
from the results obtained in this study, the following points are recommended
1. It is necessary to evaluate the financial and economics of all malaria control efforts and the cost-effectiveness evaluations must be conducted comparing different vector control activities and other control initiatives.
2. To establish targeted mosquito control programs that have significant impacts on malaria incidence and prevalence and are simultaneously cost-effective as the goal for the decision makers.
3. To apply LLIBN activity as the best vector control activity for control of malaria transmission in the studied areas.
4. Specific actions should be taken by authorities of the municipal councils that have important effect on the larval control as a primary strategy for malaria transmission, these actions should include:
1) To increase intersectoral cooperation between different malaria control authorities and engineering affairs of the local governorates.
2) To involve the community participation, to increase the efforts in application and maintenance of vector control programs
5. To focus on the larval control and source reduction, should be taken into consideration for outdoor malaria transmission.
6. Community participation on micro environment of mosquito breeding site should be encouraged which considered to be the key of mosquito control.
7. Sustainability of funding for vector control is critically important.
8. More study is required for longer period of entomological surveillance to provide more understanding of biology and behavior of malaria vectors in the study areas