Thailand is gripped by a rare public health scare after confirming its first anthrax-related death in over three decades, spurring urgent containment actions and reigniting debate over food safety and cross-border disease vigilance.

The incident, centred in Mukdahan province in the country’s north-east, has thrust anthrax—a bacterial disease more often associated with livestock—into the national spotlight, raising questions about exposure risks, food handling practices, and regional cooperation.

In late April, tragedy struck a rural community along the Mekong River. A 53-year-old man, reportedly involved in livestock activities, succumbed to anthrax on April 30th. Thai authorities swiftly identified another infection in the same area and flagged three additional suspected cases. The government responded with an all-hands-on-deck approach: health officials, livestock experts, and local authorities converged to investigate, isolate, and contain the outbreak.

Anthrax is not unknown in Thailand, but it is exceedingly uncommon. The last two human cases were documented in 2017—both survived. For context, the country’s previous anthrax fatalities date back to 1994, when three people lost their lives. Experts from leading medical research journals observe that a single death after such a long hiatus is a sobering reminder that infectious diseases can resurface unexpectedly.

What triggered this latest resurgence? Investigators traced the likely source to local food practices—specifically, the butchering and consumption of raw or undercooked beef. At least 638 people are thought to have been exposed via these routes. Among them, 36 individuals helped slaughter livestock while hundreds more ate meat that may not have been properly cooked. All are now being closely monitored and are undergoing antibiotic prophylaxis as a precautionary measure.

Health officials wasted no time in launching a large-scale response. Everyone with even a remote chance of exposure is being tracked for symptoms. Those displaying signs of illness are prioritised for testing and treatment. The Ministry of Public Health has mobilised resources to support hospitals in Mukdahan and ramp up community awareness. Educational campaigns emphasise the critical importance of safe meat handling and thorough cooking—simple steps with lifesaving consequences.

The Agriculture Ministry’s Livestock Department has drawn a five-kilometre quarantine perimeter around the suspected infection site. Livestock movement is curtailed. Veterinary teams are vaccinating over 1,200 cattle in the area—a pre-emptive strike aimed at halting animal-to-human transmission. Notably, officials say that no animals have shown overt signs of illness or inexplicable death, though all are under observation.

Prompt recognition is vital because anthrax responds well to antibiotics if caught early. Delay can be deadly. Thai healthcare workers have been urged to remain vigilant for unusual symptoms among recent beef consumers or those who participated in butchering activities.

Thailand’s current episode is not unfolding in isolation. Across the border in Laos, authorities have tallied 129 anthrax cases this year alone—with at least one fatality. Vietnam reported a cluster of 13 cases in May 2023. Regional experts point to porous borders and shared food traditions as risk factors that necessitate joint surveillance and rapid communication between neighbouring countries.

Why does anthrax persist in this part of Asia? The answer lies partly in traditional culinary habits—especially the consumption of raw or partially cooked meat—and partly in agricultural practices that may allow bacterial spores to linger in soil or animal remains.

What is Anthrax and How Is It Transmitted?

Anthrax is an uncommon yet severe infection caused by the bacterium Bacillus anthracis, a spore-forming microorganism. Primarily affecting livestock and wild animals, anthrax poses a threat to humans mainly through direct or indirect contact with infected animals. Despite its rarity, particularly in developed countries, anthrax remains a global health concern due to its potential for bioterrorism and outbreaks in certain regions. This article explores the nature of anthrax, its routes of infection, symptoms, risk factors, prevention, and treatment options.

Anthrax arises from spores of Bacillus anthracis, which naturally exist in soil worldwide. These spores can remain dormant for years until they find a suitable host, such as sheep, cattle, goats, or horses. Humans usually contract anthrax through contact with infected animals or their products—meat, hides, wool—or contaminated environments.

There is no evidence that anthrax spreads directly between people. However, skin lesions caused by cutaneous anthrax may transmit infection via direct contact or contaminated objects (fomites). The most common entry point for anthrax bacteria is through breaks in the skin such as cuts or sores. Infection can also occur after consuming undercooked meat from infected animals or inhaling airborne spores.

Although anthrax is rare in developed nations like the United Kingdom and United States, it remains endemic in parts of Central and South America, sub-Saharan Africa, Central Asia, southwestern and Eastern Europe, and the Caribbean. Sporadic outbreaks continue to threaten livestock and humans in these areas.

Four Routes of Anthrax Infection: Symptoms and Severity

Anthrax infections manifest differently depending on the entry route of spores into the body. Symptoms usually develop within six days but may take longer in inhalation cases.

Cutaneous Anthrax: The Most Common and Mildest Form

Cutaneous anthrax occurs when spores enter through the skin, often via a minor wound or scratch. It accounts for the majority of human anthrax cases and is typically the least severe form.

The infection begins as a small raised bump resembling an insect bite. This bump quickly develops into a painless ulcer with a characteristic black centre. Swelling may surround the lesion and nearby lymph nodes. Some patients experience mild flu-like symptoms such as fever and headache.

With timely antibiotic treatment, cutaneous anthrax rarely proves fatal. Left untreated, however, it can progress to more serious systemic infection.

Gastrointestinal Anthrax: Infection Through Contaminated Meat

Gastrointestinal anthrax results from eating undercooked meat from infected animals. It can affect any part of the digestive tract from throat to colon.

Symptoms include nausea, vomiting, abdominal pain, headache, loss of appetite, fever, and later severe bloody diarrhoea. Patients may also develop sore throat, difficulty swallowing, and swollen neck glands.

This form carries a higher risk of complications and death than cutaneous anthrax but remains less common.

Inhalation Anthrax: The Deadliest Form

Inhalation anthrax develops when spores are breathed into the lungs. This form is rare but highly lethal, often fatal even with treatment.

Early symptoms mimic common respiratory illnesses: sore throat, mild fever, fatigue, muscle aches, and mild chest discomfort. As infection progresses, patients experience shortness of breath, coughing up blood, painful swallowing, high fever, severe respiratory distress, shock (circulatory collapse), and meningitis.

Rapid diagnosis and aggressive treatment are critical to improve survival chances.

Injection Anthrax: Emerging Risk Among Drug Users

Injection anthrax has been reported primarily in Europe among users injecting contaminated heroin or other illegal drugs. Initial symptoms include redness at the injection site without blackening, significant swelling, shock, multiple organ failure, and meningitis.

This newly identified route highlights risks posed by contaminated substances and underscores the need for awareness in healthcare and harm reduction services.

When to Seek Medical Attention

Many illnesses start with vague flu-like symptoms similar to early anthrax signs. The likelihood that common symptoms such as sore throat or muscle aches indicate anthrax is extremely low for most people.

However, if exposure is suspected—such as working with livestock in endemic areas or handling animal products—or if symptoms develop after known exposure to potentially infected animals or substances, immediate medical evaluation is essential. Early diagnosis and treatment greatly improve outcomes.

Causes and Geographic Distribution

Anthrax spores occur naturally in soil worldwide but are unevenly distributed. Animals grazing on contaminated land become hosts; humans acquire infection mainly through occupational or environmental exposure.

While rare in developed countries due to stringent animal health controls and vaccination programmes, anthrax remains endemic in many developing regions. Sporadic outbreaks continue among livestock and wildlife.

Human cases often arise from handling infected animal products like hides or wool. Examples include drum makers using traditional African skins contaminated with spores.

Notably, bioterrorism has caused isolated outbreaks—such as the 2001 US mailing of anthrax spores resulting in 22 infections and five deaths—and recent heroin-related outbreaks in Europe causing dozens of fatalities.

Risk Factors for Anthrax Infection

Contracting anthrax requires direct contact with spores. Individuals at increased risk include:

• Military personnel deployed to endemic regions
• Laboratory workers handling anthrax cultures
• Veterinarians treating livestock
• Workers processing animal skins, fur or wool
• Hunters or handlers of game animals
• Injectors of contaminated illicit drugs

Understanding these risk factors helps target prevention efforts effectively.

Potential Complications

Anthrax complications can be severe:

• Sepsis (widespread infection causing organ damage)
• Hemorrhagic meningitis (brain membrane inflammation with bleeding)
• Multi-organ failure
• Death if untreated or advanced

Prompt treatment significantly reduces these risks.

Prevention Strategies: Vaccines and Antibiotics

Prevention focuses on avoiding exposure and post-exposure prophylaxis:

• Avoid contact with livestock or animal products in endemic areas
• Cook meat thoroughly before consumption
• Handle dead animals with caution
• Use protective equipment when working with potentially infected materials

The US Centers for Disease Control and Prevention (CDC) recommends 60 days of antibiotic treatment (ciprofloxacin, doxycycline or levofloxacin) plus a three-dose vaccine series following exposure. Monoclonal antibodies such as raxibacumab may also be used in some cases.

The anthrax vaccine does not contain live bacteria and cannot cause infection but may cause side effects ranging from mild injection site soreness to rare allergic reactions. It is reserved for high-risk individuals—military personnel, scientists working with anthrax, veterinarians in endemic zones—but not for general public use.

Treatment Approaches

Early antibiotic therapy cures most anthrax infections except advanced inhalation cases which require intensive care. Supportive measures address complications like shock or meningitis.

New treatments including monoclonal antibodies improve survival rates in inhalation anthrax but remain adjuncts to antibiotics.

The Global Perspective: Ongoing Challenges

Although rare in high-income countries due to veterinary controls and vaccination efforts, anthrax persists as a health threat globally. Its environmental persistence in soil makes eradication difficult. Outbreaks still occur sporadically among livestock and wildlife.

Bioterrorism remains an unsettling possibility given spores’ resilience. Additionally, drug-related injection anthrax underscores social determinants impacting disease spread.

Continued surveillance, research on vaccines and treatments, education on safe animal handling practices, and harm reduction strategies are vital components of global anthrax control.

Anthrax may be uncommon but understanding its various forms, recognising symptoms early, knowing risk factors, and following prevention guidelines are critical steps in safeguarding individual and public health against this serious bacterial threat.