A 14-year-old student in Shandong died of anthrax infection! How contagious is it? How to prevent it? The answers are all here

Expert in this article: Dr. Tian Jing, attending physician at the Southern Theater Command Center for Disease Control and Prevention

Reviewer of this article: Chen Haixu, Deputy Director and Master Supervisor of the Second Medical Center of PLA General Hospital

On August 27, the news of #anthrax death case in Shandong# attracted widespread attention.

According to the August 27 report of the China CDC Weekly, as of August 15, the Shandong Provincial Center for Disease Control and Prevention reported two confirmed cases of anthrax in Binzhou, one in a 14-year-old student (Patient A) and the other in a 35-year-old man working in slaughterhouses (Patient B).

Patient A died on August 6, and patient B has been transferred to an infectious disease hospital for isolation and treatment.

It is reported that recently, anthrax outbreaks have also been reported in Shanxi, Beijing, Inner Mongolia and other places in my country.

Anthrax is a highly contagious disease. Once it occurs, we must never take it lightly and must actively prevent and control it.

To prevent and control the epidemic, we must first understand the epidemic: What is anthrax? What are the symptoms of anthrax infection? How to prevent it? Let's take a look at the key points!

What is anthrax?

Anthrax is a highly lethal infectious disease caused by a bacterium called Bacillus anthracis that can be transmitted between humans and animals, causing illness in both humans and animals.

Anthrax Bacillus originally exists in the soil. Various wild animals and livestock, especially herbivores such as cattle and sheep, can be infected through eating contaminated feed, drinking water, breathing, insect bites, etc.

Sick animals often die suddenly due to the disease, with bleeding in the mouth, nose, anus and other parts of the body, and symptoms such as incomplete rigor mortis. Humans may be infected after coming into contact with the feces, corpses and contaminants of these sick animals.

The regions with high incidence of anthrax in the world include Latin America, sub-Saharan Africa, South Asia, West Asia and Central and Southern Europe. There have always been cases of anthrax infection in my country, but the incidence rate is very low.

Anthrax is classified as a Class B infectious disease in my country and is subject to direct reporting, while pulmonary anthrax needs to be managed as a Class A infectious disease.

Why is Bacillus anthracis so tenacious?

Bacillus anthracis has a strong tolerance to the environment and can form dormant spores under conditions that are not conducive to its survival. It can survive for more than ten years or even tens of thousands of years. When encountering suitable living conditions, the spores can germinate into bacterial cells.

Therefore, it is difficult to eliminate contaminated water sources, soil and sites, and permanent sources of infection are formed. Once unimmunized foreign animals enter the old epidemic areas, they are likely to become infected and fall ill.

Anthrax is rarely contagious between people, but in rare cases, cutaneous anthrax spread from skin lesions may be contagious. However, if human excreta is not properly disposed of, it may contaminate the environment, infect animals, and eventually humans.

At present, research on anthrax epidemics in China mainly focuses on small-scale cases of zoonotic transmission. Due to different transmission routes, the dose of Bacillus anthracis that causes human infection has not been clearly defined, and there are still certain difficulties in detecting anthrax in the environment.

What are the symptoms of anthrax infection in humans?

When anthrax spores enter the human body, they will be activated, and the bacteria will multiply in the body, produce toxins, and make people sick. There are three common ways for them to enter the human body:

1. When the skin is exposed to these pollutants, bacteria will form skin anthrax through tiny wounds on the skin, which manifests as erythema or papules, forming blisters, and forming black scabs after necrosis, namely "skin anthrax";

2. Eating contaminated meat can cause "intestinal anthrax", with symptoms such as high fever, abdominal pain, diarrhea, vomiting blood, and black stools;

3. The fur and excrement of sick animals contain anthrax Bacillus, which may form aerosols and be inhaled, which may cause "pulmonary anthrax". The early symptoms are similar to pneumonia, and then develop into high fever, shortness of breath, and respiratory failure.

Usually, 95% of patients suffer from "cutaneous anthrax", and most of them can recover after treatment, with a mortality rate of less than 1%. The most serious is "pulmonary anthrax", with a mortality rate of over 90%. The mortality rate of "intestinal anthrax" is in the middle, and untimely treatment may lead to death.

A less common form of anthrax infection has been found in heroin injectors in northern Europe and is similar to "cutaneous anthrax" but infects deeper layers of the skin or muscles.

How is anthrax infection treated?

Bacillus anthracis is a Gram-positive bacterium that can be treated with antibiotics that are effective against this bacteria, such as penicillins, cephalosporins, and aminoglycosides. Penicillins are generally the first choice.

The early specific symptoms of infection are not obvious and may appear within one day or more than two months after infection. In the late stage of infection, a large number of bacteria multiply and conventional antibiotics are difficult to control. The bacteria spread throughout the body and endanger life. Therefore, patients should be isolated early, diagnosed as soon as possible, and treated actively.

How to prevent anthrax?

1. Do not eat, slaughter, sell or touch animals and corpses that died suddenly, do not buy animal products of unknown origin and meat without animal quarantine certificates, and do not eat raw meat.

2. Once the sudden death of cattle, sheep, etc. is discovered, it should be reported immediately and disposed of in a harmless manner.

3. Vaccinate susceptible animals and implement strict animal epidemic prevention and quarantine. Workers engaged in animal husbandry and slaughtering should be vaccinated with anthrax live attenuated vaccine once a year for 2-3 consecutive years.

4. Strengthen water source management and prevent water pollution.

5. If any sick person is found, he/she should be isolated and treated immediately and placed under strict medical observation.