Diseases early warning and surveillance is a very important sector in healthcare. It is concerned with controlling infectious diseases, a task which will lead to a timely prevention and mitigation work. The current diseases early warning and surveillance systems has short comings such as manual carpet reporting, data and process centralization, tractability problems and data security issues. In this paper we proposed blockchain based model for disease early warning and surveillance tasks. Our model utilizes the desirable features of the blockchain technology which are decentralization, immutability, security and tractability. We designed our model using the ethereum blockchain platform this model includes the tasks involved in diseases early warning and surveillance namely checking surveillance report completeness, surveillance data reporting, laboratory result reporting and analysis of reported surveillance data. Furthermore, based on our model we developed a prototype using the ethereum platform and used this prototype for evaluation of our model. Our evaluation assesses how valuable the features, functionality, content and transactions of our model are to the domain area and also how easily and efficiently users can complete their tasks using the prototype. Taking this assessment criteria in to consideration we have conducted performance, usability and security evaluation.The performance evaluation has demonstrated that the block generation time for 12 blocks in 10 experiments was 12 to 14 seconds which is a fast and stable block generation time. We conducted our usability evaluation using SUMI(Software Usability Measurement Inventory),a standardized usability evaluation tool, and the evaluation results achieved a maximum score of 68.96 and minimum score of 60.46 for the SUMI evaluation scales where the possible maximum score is 73.Furthermore we conducted security evaluation by defining a thereat model and conducted assessment for security risk scenarios.The result for this assessment implies that our model is safe and secure solution.Summing up, our evaluation verifies that our model is a distributed, secure, immutable and traceable solution to the research problem that we have studied.