• Determine the ecological relationship between viruses, bacteria and algae communities to the healthy and diseased coral communities in some main areas.
• Initially proposed measures to limit the harm caused by microorganisms in order to protect the coral health and sustainable development of coral ecosystems in the study areas.

Scientific results
- A series of new research results, synchronization on bacteria, viruses and algae associated with coral in coast of Cat Ba and Long Chau Islands, Hai Phong was made with advance methods which are using in developed countries by Vietnamese researchers. These are valuable data that can be used as background material for comparison to other later studies.
- The research results on the state of distribution and abundance variation in the temporal of bacterial groups, viruses, and symbiotic algae (zooxanthellae) in the mucus environment of 18 coral species as well as in the water environment in coast of Cat Ba and Long Chau Islands, Hai Phong. Those are very important data to contribute to assessment of the diversity and ecological coral microbial communities.
- The number research data on structural community of bacteria, viruses, coral symbiosis algae as well as the relationship between them. For bacterial community, have been quantified main morphological groups of bacteria, number of OTUs in the samples, the ability to absorb and metabolize 31 compounds belong to 6 organic groups of bacteria. For viruses, have determined density and abundance variation of viral particles in the research environments (coral mucus, water surrounding, between Long Chau and Cat Ba sites). For micro-algae (zooxanthellae), have determined density and abundance variation in research environments.
- Initially data on the characteristics of the bacterial, viral and micro-algae (zooxanthellae) communities on some coral species in healthy and disease status (white band and red spot diseases) in the study area. These initial results are valuable data for study on the role of microorganisms in the coral health.
- Base on this research data and other references, a protocol was proposed to assess coral health and contribute to sustainable development of coral reef ecosystems.
 In applications
- A protocol was proposed to assess coral health and contribute to sustainable development of coral reef ecosystems.
- Results of this research are a new and useful data for scientists, students and managers to reference in research and education.

A series of new research results, synchronization on bacteria, viruses and algae associated with coral in coast of Cat Ba and Long Chau Islands, Hai Phong was made with advance methods which are using in developed countries by Vietnamese researchers. These are valuable data that can be used as background material for comparison to other later studies.