Immunity as the Greatest Defense System and Its Role in Preventing Infectious Diseases

Immunity is the most significant defense system of the human body, and the immune system is a crucial part of it. When immunity is low, individuals are more susceptible to bacterial or viral infections, leading to an increase in the incidence of various diseases. Immunological screenings are essential before surgeries and during pregnancy checks, as they can detect the presence of infectious diseases. However, the specific content of these screenings may vary between different hospitals.

The four main components of immunological screenings in various hospitals can differ significantly:

1. The first set typically includes rheumatoid factor, erythrocyte sedimentation rate, C-reactive protein, and anti-streptolysin O.

2. The second set comprises tests for HIV, hepatitis B virus, hepatitis C virus, and syphilis.

3. The third set mainly involves four types of immunoglobulins: immunoglobulin A, immunoglobulin G, immunoglobulin M, immunoglobulin E, complement C3, and complement C4.

Regarding the accuracy of immunological screenings for HIV, they can indeed detect the virus. A positive result indicates infection, but it's worth noting that there is a window period after initial infection. HIV, or acquired immunodeficiency syndrome (AIDS), has become a serious public health issue globally, threatening the health of people worldwide.

HIV primarily targets and destroys T4 lymphocytes, which are crucial in the human immune system. This destruction weakens the immune system, eventually leading to its collapse and making the body susceptible to various diseases and infections. The initial stages of infection may present with symptoms similar to the flu or serum sickness, followed by a prolonged asymptomatic period. Over time, the infection progresses to the advanced stages of AIDS, leading to severe opportunistic infections and malignancies.

Scientists refer to the virus that causes AIDS as "human immunodeficiency virus" (HIV). The incubation period of HIV in the human body averages 12 to 13 years. During this time, infected individuals may appear outwardly normal and can live and work without any symptoms for many years. December 1st of every year is observed as World AIDS Day.

Unfortunately, there are no effective curative measures for AIDS, and successful treatment cases are rare, making it a challenging "super cancer." As for the turnaround time for immunological screenings, they are generally available at county-level hospitals, and the results can be obtained on the same day. In tertiary hospitals, the results may be available within approximately one hour. Typically, blood samples are collected in the morning, and the results are available in the afternoon.

The immunological screenings for antibodies typically involve checking for HBV, HCV, HIV, and syphilis markers, including anti-sperm antibodies, anti-ovarian antibodies, anti-cardiolipin antibodies, and anti-endometrial antibodies. These screenings can be performed through blood tests at tertiary hospitals, usually without special preparation or specific timing.

The benefits of immunological antibody screenings are numerous. Firstly, they assist in clinical diagnosis, serving as indicators for observing the efficacy and prognosis of certain diseases. Additionally, they play a crucial role in monitoring the effectiveness of vaccinations and in epidemiological investigations of infectious diseases. Given the challenges associated with directly detecting pathogens from samples due to their specific growth requirements, long incubation times, and low positive detection rates, the detection of specific antibodies can compensate for these limitations to a certain extent.