Infectious disease experts warn about the potential health risks of naturally occurring anthrax, which threatens millions of people and livestock around the world.
Many people know anthrax as a bioterrorism weapon cultured in laboratories. However, some bacteria can also be found living in natural settings. Wildlife and livestock, such as pigs, cattle, goats, and deer, can easily pick up the microorganisms through the air they breathe or the grass that they feed on.
The infection can then be passed on to humans who get in direct contact with sick animals, or if they eat tainted meat.
This form of threat is what researchers from the Centers for Disease Control and Prevention and several American universities explored in their research.
The Threat Of Naturally Occurring Anthrax
In a study featured in the journal Nature Microbiology, University of Florida associate professor Jason Blackburn led a team in investigating the public health risk of anthrax infection found in the environment.
He was joined by fellow researchers, including Colin Carlson from Georgetown University, and Ian Kracalik, an epidemic intelligence officer from the CDC.
First on the research team's task list is to fill in gaps in data regarding anthrax cases.
Most instances of infection are left underreported because some people mistake it for other diseases. Anthrax often shows symptoms that are quite similar to those of other illnesses, making it difficult to diagnose without proper testing.
Hunters and herders also do not report cases of anthrax in wildlife and livestock because they are afraid that it might affect their livelihood.
People And Livestock At Risk Of Infection
To solve this problem, Blackburn and his colleagues examined 15 years' worth of health data so that they could identify particular anthrax hotspots in the world.
They discovered that as many as 1.83 billion people live in regions where anthrax is found naturally occurring. An estimated 63 million of these are livestock keepers who are at a high risk of infection.
Meanwhile, 1.1 billion livestock are currently kept in areas where the bacteria is present.
The researchers also determined which particular parts of the world would anthrax most likely occur. They examined soil characteristics and climate data to pinpoint where these areas could be.
The anthrax bacteria is known to thrive in arid and semi-arid climates with moderately alkaline soil. However, it can also be found in regions with temperate highlands such as those in China.
The team also examined the population of humans, livestock, and wild animals that live in these areas.
Results showed that Bangladesh, China, India, and South Africa are the countries that have the most number of people at risk of anthrax infection.
Some parts of North America is also susceptible to a bacterial outbreak. However, public health officials in these areas routinely vaccinate livestock to keep them safe from anthrax.
Food safety agencies also make sure that tainted meat are kept off the market and people's tables.
Vaccinations may help prevent the spread of anthrax infection in livestock, but they may not be easy solutions. The treatment must be administered in the animals annually, which could drive up costs.
The researchers said anthrax vaccine is also not readily accessible to poor countries, which are often the most at risk for the bacterial infection.
CDC epidemiologist Antonio Vieira said anthrax infection can cause "significant" economic and public health problems for affected countries, especially those with poor, rural communities.
In an email to news website NPR, Vieira said being able to map anthrax hotspots is important and helpful for preparedness and targeting interventions.
What Is Anthrax?
Anthrax is a highly infectious disease caused by the Bacillus anthracis bacteria. The CDC lists anthrax agents as Tier 1 threats, which means they pose a significant threat to public health and safety.
The infection can cause mass casualties or severe disruptions to the economy, critical infrastructure, or public confidence of affected countries.