Evaluation of efficiency and eleven-year longitudinal surveillance of malaria after its basic elimination in Shandong Province.

In order to consolidate the achievement of malaria control we have worked out an applicable strategy for malaria control and surveillance in our whole province since malaria elimination in 1988. The complex control measures with the emphasis of eradication of infected sources in the whole province, conducting united control in the five pre high epidemic cities or districts in southern parts of the province, setting amount of professional and part time microscopic examination spots responsible for blood examination of “four fever” patients, managing of mobile population and applying of every anti malaria measures have been carried out continuously. In the hypo epidemic malarial areas, the classification management also has been applied. In every medical agency which could be able to conduct microscopic examination has taken blood exam of plasmodium as an examination rule. During the eleven years (1988~1999), 7 790 941 local residents were examined by blood, 141 of them were positive with a positive rate of 0.18 per ten thousand, 306 581 returned people from abroad were examined, 217 of them were positive with a positive rate of 7.08 per ten thousand and 247 of 217 635 persons coming back from malaria epidemic areas were positive with a positive rate of 11.35 per ten thousand, those showed a remarkable difference among the three types of people (χ 2=9 602.97, P0.001). Meanwhile, 10 malaria monitoring sites were set up in representative townships selected according to different geographic areas and economic condition to be responsible for blood examination of the “four fever” patients and surveillance of vector mosquitoes in their jurisdiction. The results showed that in the malarial epidemic areas where only Anaopheles sinensis is considered to be the vector, after basic elimination of malaria only to strengthen management of mobile population and to preventive import and dispersion of foreign cases are enough for consolidating the achievement of malarial control and eradicating malaria at last.