Illustrate the definition, method and significance of immigration epidemiology with examples!

Immigrant epidemiology is a branch of epidemiology, which studies the incidence or mortality of diseases when people with certain characteristics migrate from one country to another country with different environments (or from one area of China to another), and compares the incidence or mortality of residents in the immigration area with those in the immigration country or the country of origin, so as to explore the causes or epidemic factors.

For example, immigration epidemiology can be expressed in the following simple form:

CO is the mortality rate of the disease in the original country of residence, M is the mortality rate of immigrants, and CA is the mortality rate of the country where immigrants live.

1. If environmental factors are the cause of the observed mortality change, it can be seen that CO is different from M, and the value of M will gradually approach the value of CA over time.

2. If genetic factors are the cause of the observed mortality change, we can see that CO and M are the same, but CO, M and CA are different.

Method:

1. Collect general information of immigrants, such as gender, age, occupation, time and place of birth, records of living place in one's life, nationality and change, nationality, religion, language, social status and economic status, and information of parents.

2. Collect indicators related to genetic factors, such as the incidence and death of relatives, clinical and biochemical test results, etc. , collect genealogy charts if necessary.

3. Collect environmental indicators, such as food, living habits (smoking, drinking, etc. ) and other environmental indicators. Pay special attention to environmental factors that change with time.

4. Collect data on disease frequency and immigrant population.

The significance of immigration epidemiology;

Immigration epidemiological investigation is mainly applied to the study of chronic diseases. At present, it is mainly used for the study of the following diseases:

1. Research on cardiovascular and cerebrovascular diseases of immigrants: such as cerebrovascular diseases, atherosclerotic heart disease and hypertension of immigrants.

2. Research on the occurrence of tumors among immigrants, such as nasopharyngeal carcinoma, gastric cancer and esophageal cancer among immigrants.