A 3-year-old boy died after being bitten by a dog. Why did he get sick after being vaccinated with rabies vaccine?

Recently, the news that a 3-year-old boy in Henan died after being bitten by a dog has attracted people's attention. According to media reports, the boy died before he had time to receive the fifth rabies vaccine.

From being bitten to passing away, what kind of pain and suffering did the boy go through? Why did he still die after being vaccinated against rabies? This issue of "Health Focus" explains it for you.

3-year-old boy was bitten by a dog and died 18 days later

Based on media reports and official announcements, let’s take a look at what the boy experienced from the time he was bitten to his death.

The boy was bitten on the afternoon of April 21. He was playing on the road near Zhaogang Village, Xinye County, Henan Province, when a husky suddenly ran out and attacked him, causing him to be seriously injured. The boy's legs, neck, and the area around his eyes were bitten off, and there were several large tooth marks behind his ears and on his neck, and there were many broken skin areas on his body.

On the same day, the family took the child to get a rabies vaccine, but there was a shortage of rabies immunoglobulin in the countryside. And because the child was seriously injured, the family immediately took the child to Nanyang City, where they found a 24-hour dog bite treatment and vaccination clinic. They cleaned the wound, injected rabies immunoglobulin (i.e., rabies passive immunization preparation), and arranged for hospitalization at Nanyang Central Hospital.

He was discharged on May 1. The boy was hospitalized in Nanyang Central Hospital for 9 days and was discharged.

The condition began to deteriorate on May 7. The child's mother said that the child was in good condition in the first few days after being discharged from the hospital, but the condition began to deteriorate on May 7.

She was rushed to the ICU on May 8. The child vomited frequently and was in a manic mood. On the evening of May 8, she was rushed to the ICU of Nanyang Maternal and Child Health Hospital for treatment.

He passed away on May 9. In the early morning, the child was sent to Henan Provincial People's Hospital in Zhengzhou for emergency treatment, but the boy's life could not be saved.

In fact, this is not the first time such a tragic incident has occurred:

In July 2017, a 32-year-old woman in Xi'an was bitten on the outer and inner ankles of her left leg by a stray dog. After the incident, the woman was promptly injected with rabies vaccine. Unfortunately, she still died of rabies 28 days later.

In September 2018, a 6-year-old boy in Zhejiang died of rabies after being bitten by a dog near his home and receiving three rabies shots.

In April 2019, a 3-year-old girl in Jiangsu was scratched by her classmate's pet dog on her way home from school. She died of a fever after getting a rabies vaccine at the hospital.

Why do people still get rabies after being vaccinated?

Some netizens questioned whether there was something wrong with the vaccine, but this was denied. The Nanyang City Center for Disease Control and Prevention, the Nanyang Xinye County Center for Disease Control and Prevention, and the Nanyang Wolong District Center for Disease Control and Prevention all stated that they had completed a preliminary investigation into the matter and found no abnormalities in the management of rabies vaccines and passive immunization preparations (drug procurement, transportation and storage), rabies exposure treatment (wound treatment, injection of rabies vaccines and passive immunization preparations), and medical treatment.

Rabies vaccines and rabies passive immunization preparations

Earlier, Yin Wenwu, chief physician of the Department of Infectious Disease Prevention and Control of the Chinese Center for Disease Control and Prevention, said in an interview with NetEase Health that the sooner the rabies vaccine is administered, the better. It is generally recommended to administer the rabies vaccine within 24 hours. If the vaccine is administered after 24 hours, it is best to administer it as soon as possible, just like those who have just been exposed, so that the vaccine can take effect before the onset of the disease. It usually takes about a week for the vaccine to stimulate the body to produce the corresponding antibodies.

Yin Wenwu introduced that anti-rabies immunoglobulin (human rabies immunoglobulin) and anti-rabies serum (horse rabies immunoglobulin) are both passive rabies immunization preparations. The mechanism of action of passive rabies immunization preparations is that before active immunity is produced by vaccination, antibodies are directly injected into the exposed area to neutralize the virus remaining after wound treatment, thereby reducing the virus content in the wound to reduce the probability of disease. If the injection is not timely, it can be supplemented within 7 days after the first dose of rabies vaccination. Rabies passive immunization preparations and rabies vaccines are irreplaceable.

The circumstances under which rabies vaccine and rabies passive immunization preparations are needed should be determined based on the degree of exposure.

Level 1 exposure: The skin is intact and not broken, there is no contact with the body's mucous membranes, the virus has not entered the body, and no treatment is required.

Secondary exposure: If the skin is broken but there is no bleeding, the virus may have entered the body. Wash the wound with soap and running water for 15 minutes, and then get a rabies vaccine.

Level 3 exposure: The skin is broken and bleeding, and the virus is likely to enter the body. Treat the wound immediately, and inject rabies passive immunization preparations and rabies vaccines.

The WHO position paper on rabies vaccines states that rabies can be effectively prevented by immediately initiating measures upon exposure. However, a variety of other factors, such as delayed medical treatment, unobserved wounds, direct virus invasion of nerves, patients’ noncompliance with vaccination procedures, and extremely low individual immunity, may lead to failure of exposure prevention measures and death. If the head or face is bitten, the amount of infected virus is large, the virus can quickly invade the nerves and the central nervous system, and the incubation period can be as short as a few days. The patient may become ill before the immunization measures take effect.

The mortality rate of rabies is almost 100%

Yin Wenwu introduced that the mortality rate of rabies is almost 100%. The reason is that the rabies virus is a neurotropic virus (it has a very strong affinity for nerve tissue).

After the rabies virus enters the body through the skin or damaged mucous membranes, it will enter the central nervous system along the nerve endings and then replicate in large quantities. The immune defense of the central nervous system itself is relatively weak. Due to the existence of the blood-brain barrier, the antiviral immune system cannot enter the central nervous system and cannot effectively control the virus, so it can replicate in large quantities in the central nervous system.

It only takes 24 hours for the rabies virus to enter the brain and completely destroy the central nervous system. Once the important functional areas of the central nervous system are destroyed, the person will die immediately. From the onset of the disease, it usually takes less than 5 days to kill a person. In such a short time, no drug can eliminate the virus without damaging the central nervous system.

Although the probability of rabies immunization failure is relatively low, what if it happens to you? The little life has passed away, and the owner of the vicious dog is still unknown. The local police are actively investigating.