Detecting how the bird flu virus kills

The group of international scientists in Ho Chi Minh City has discovered how the H5N1 virus kills people and opens up the prospect of more effective prevention of epidemics at risk of mass destruction.

Doctors at the Ho Chi Minh City Tropical Hospital collaborated with international scientists to compare 18 bird flu victims with people with regular flu viruses in 2004 and 2005.

Results of the mechanism of action of the H5N1 virus and the regular influenza virus in patients were published in Nature Medicine on Monday. This announcement immediately shocked the international scientific community.

Concentrate in the throat and spread everywhere

The first significant finding was to find the area in the body where the H5N1 virus was most concentrated. Tests show that the H5N1 virus gathers with the highest density in the patient's throat.

Care and treatment for patients with pneumonia caused by H5N1 virus at the Institute of Clinical Medicine of Tropical Diseases.(Photo: Huu Oai, TTO)

This is in stark contrast to the normal mechanism of influenza virus activity if it is known that the flu virus is normally concentrated in the nose. This finding alone has helped physicians find a way to more accurately sample and diagnose diseases.

Previously there was a phenomenon of taking patients' specimens from the nose to finding the H5N1 virus and as a result there were many cases of late or late detection.

The second important finding is the mechanism of unusual activity of the H5N1 virus. On the one hand, the H5N1 virus is capable of multiplying itself by a higher level than the regular influenza virus. They penetrate into the bloodstream and spread quickly throughout the body parts.

The H5N1 virus was found in the blood of at least 9 people. They even found H5N1 in the intestines of most patients, especially the number of deaths. That said, the H5N1 virus could wriggle from the respiratory system through the bloodstream to the digestive system. In contrast, of the 8 patients with regular flu, no influenza virus was found in the blood nor in the patient's digestive system.

Researchers said that when the H5N1 virus flooded its body parts, the victim's immune system was forced to react by creating widespread anti-inflammatory responses.

Normally, when an infection occurs, the body's immune system directs blood vessels to release chemicals and blood cells into the affected area to fight the intruder. These chemicals are a protein called cytokine (roughly translated as kinetic cells), according to Menno de Jong (Department of Clinical Research, Oxford University), in partnership with Ho Chi Minh City Tropical Hospital, and is the research leader. However, if this period is overkill, it will be dangerous. Researchers found very high levels of cytonkine in H5N1-infected patients and were particularly high in patients who died from H5N1.

Contrary to the increase in abnormalities of cytonkine, the lymphocytes are severely impaired in peripheral blood vessels. In short, it is the excessive concentration of abnormal viruses in an area that triggers an overreaction of the immune system, causing death for patients. This excessive response and spread to other parts of the body, plus virulence of the virus, causes patients to die quickly.

Evidence confirms that antiviral drugs

One of the measures to stop the speed of self-replication and spread is diagnosis and early detection. Determining the highly concentrated H5N1 virus in the throat instead of the nose, according to doctors, will help a lot for early diagnosis and detection.

The findings of international scientists with research in Vietnam also help to generate a new direction of thinking in the production of antiviral drugs. It is necessary to have a drug that can help reduce the rate of viral replication to avoid danger to the lungs and prevent the body's risk of excessive inflammation.

The good news is that existing antiviral drugs like Tamiflu, Relenza, or Amantadine are likely to help meet this goal. They will help reduce the density of the H5N1 virus, limit the replication of the virus itself and, thereby, prevent the excessive immune response, the ultimate cause of death, Menno de Jong said. .

In Vietnam, according to an official of the Drug Administration of Vietnam, 4 GMP-certified pharmaceutical companies of the Ministry of Health are urgently producing Tamiflu drugs under the copyright of Roche, Switzerland.

A state-level research program on active ingredients for Tamiflu is also being conducted by the Vietnam Institute of Science and Technology in collaboration with the Ministry of Health. Research branch, however, has not progressed well.