ESTABLISHING AN EPIDEMIOLOGICAL SURVEILLANCE SYSTEM FOR COMMUNICABLE DISEASES OF COUNTRY

Nguyen Kim Tien*, Ha Ba Khiem*, Tran Tien**, Nguyen Thu Yen**, Luong Chan Quang

*:Pasteur Institute HoChiMinh City, **INHE, Ha Noi.

In Vietnam, communicable disease is still one of the most prevalent patterns. Yearly, the epidemics occur in some areas such as Typhoid fever in Kien Giang province (1993) and HoChiMinh City (1995), Cholera in Hue and Minh Hai (1995).

The epidemiological surveillance system in Vietnam still remains some difficulties. The diagnosis of diseases mainly depends on clinical signs, therefore the information of morbidity and mortality is not sufficiently precise, reports from government health services or private health services have not strictly been carried out and timely transferred to the health authorities.

Hence, the objects of the study are the followings:

OBJECTS

1. Setting up an active epidemiological surveillance system, basing on available one, but intensifying some activities: training on surveillance skills, using microbiological diagnosis for some communicable diseases, improving data dissemination system (reporting and feedback).

2. Applying active surveillance data in intervention on typhoid fever and dengue heamorrhagic fever.

3. Evaluating the active surveillance system.

METHODS AND RESULTS:

The experimental surveillance system was implemented in Hung ha district (Thai Binh province) and Cai lay district (Tien Giang province). All of health staff of preventive system, hospitals and laboratories from provincial level to commune level was trained on clinical identification, laboratory diagnosis, epidemiological surveillance skills and microcomputer communication network application. A laboratory system was established in order to confirm first case of the endemic, the suspected cases of communicable diseases. This system, responsible by the technician of laboratories, included specimen collection and transportation procedure, laboratory test performance, and tested result reporting. The laboratory results were updated to the weekly and monthly communicable diseases report form. These weekly and monthly reports were disseminated to the upper level of preventive system, especially by computer net in the district and provincial level.

After one-year study (from November 1997 to October 1998), the experimental surveillance system detected twice to three times more cases than the available one because cases were reported sufficiently, no missing case and many cases were detected from village level. Furthermore, these cases were diagnosed more exactly due to the diagnostic criteria and the laboratory diagnosis confirmation. The reports of the experimental surveillance system were disseminated more punctually due to the computer net. This experimental system also rejected the overlap cases.

By using the surveillance data, the typhoid fever intervention pattern was established. Positive blood culture typhoid fever patients and their relatives were surveyed and monitored in hospital and in their houses. They were treated based on the antibiogram result of blood and stool culture.

CONCLUSION

The experimental active surveillance system was successfully established in organization aspect as well as in technical aspect in the study sites. It is proved that establishing the active surveillance system is necessary and useful in terms of controlling effectively outbreak of communicable diseases. It provides the accurate, complete, and punctual data, so that, the epidemic control will perform timely and effectively. This active surveillance system should be expanded to the other sites.