What is anthrax?
Anthrax is a very rare but serious infection caused by the bacteria (bug) Bacillus anthracis. The disease is found in animals and humans across sub-Saharan Africa and Asia, in several southern European countries, in the Americas, and certain areas of Australia. Fortunately, humans are rarely infected. Anthrax bugs can exist as spores that can survive in the environment, e.g. in soil, for many years.
How does anthrax affect humans?
There are three forms of human disease depending on how a person catches anthrax: cutaneous (through the skin), inhalation (through breathing) and ingestion (through eating). Most cases (95%) are skin infections (cutaneous), generally caught by touching the skin or other body parts of animals with anthrax.
Inhalation anthrax (caught by breathing in anthrax spores) is not common anymore. It used to be called “woolsorters’” disease because it was common in woollen mill workers in Northern England 100 years ago. It was a known danger at work for some workers, including woollen mill workers, abattoir workers, tanners, and those who processed hides, hair, bone and bone products. Intestinal anthrax is very rare, and is caught from eating meat from an animal infected with anthrax.
How common is anthrax?
Anthrax is very rare. The last case in Ireland was more than 100 years ago. A handful of cases have been found in the UK in the last 20 years. Human infections are more common in countries where the disease is common in animals, including countries in South and Central America, Southern and Eastern Europe, Asia and Africa.
Can you catch anthrax from animal hides (skins)?
Anthrax infections from touching untanned animal hides (skins) are rare. In countries where anthrax is endemic (where anthrax never goes away; for example many countries in Africa and Asia always have some cases of anthrax), animal skins sometimes have anthrax bugs on them (contaminated). Livestock (farm animals) in Ireland very rarely have anthrax. No case has been seen in an Irish animals since 1970.
Although the danger is usually very low, if a person brings untreated animal hides (skins) into Ireland the danger may be higher. A small number of people have caught anthrax by making or playing drums which were made with dried animal hides (skins) which were brought into the country from places where anthrax is more common.
How long can you have the infection before developing symptoms?
In general, you feel unwell (symptoms start) within 2 days of breathing in anthrax (inhalation anthrax). Usually skin infection (cutaneous anthrax) symptoms start 1-7 days after touching animal hides (skins) or body parts with anthrax on them.
What are the symptoms?
Noticing the symptoms of anthrax in the beginning can be difficult. The first symptoms are similar to other illnesses.
Cutaneous anthrax – skin infection.
- Commonly seen on hands, forearms, head and neck. The lesion is usually single.
- 1-7 days after exposure a raised, itchy, inflamed pimple appears followed by a papule that turns vesicular (into a blister). Extensive oedema or swelling accompanies the lesion – the swelling tends to be much greater than would normally be expected for the size of the lesion and this is usually painless
- The blister then forms an ulcer, followed by a classical black eschar (scar) 2-6 days later
- If left untreated the infection can spread to cause blood poisoning
Inhalation anthrax - symptoms begin with a flu-like illness (fever, headache, muscle aches and non-productive cough) followed by severe respiratory (breathing) difficulties and shock 2-6 days later. If untreated the infected person usually dies. Treatment must be given as soon as possible to reduce the risk of death.
Intestinal anthrax is caught by the eating animals which had anthrax and results in severe disease which can cause death. This is found in some parts of the world where the value of an animal dying unexpectedly outweighs any fears of catching anthrax.
Can anthrax be treated?
Cutaneous (skin) anthrax can be cured with antibiotics. The risk of death is higher when anthrax is caught by breathing in (inhalation anthrax) or eating (intestinal). Noticing the symptoms early and starting treatment early makes it more likely the treatment will be successful.
Can you catch anthrax from another person?
Anthrax does not usually spread (move) between people. It is NOT normally contagious. You cannot catch anthrax from another person the way you might catch a cold or the flu. A very small number of people have caught anthrax from the skin of someone who had cutaneous (skin) anthrax.
Is there a vaccine?
There is a vaccine against anthrax, but it is not normally available to the general public. It is not normally recommended for those at slight or occasional risk and isn’t of value in the short term.
I make drums – what can I do to protect myself?
People who make drums should only use animal hides (skins) that have been processed to reduce the chance of infectious disease transmission. Anyone with ongoing exposure to untreated animal hides (skins) should consider adopting the following measures:
- Work in a well-ventilated workspace that does not exhaust into other work or living areas
- Use disposable gloves when handling hides and cover all cuts, abrasions or broken skin with waterproof dressing.
- Avoid putting your fingers in your eyes, nose, or mouth.
- Cover all exposed skin with clothing (long trousers, long sleeves)
- Avoid where possible or reduce activities that raise dust (dry sweeping, or using compressed air; shaking, beating or scraping hides vigorously).
- Wear a disposable face mask of FFP3 standard. Such a mask must be fitted properly to the face in order to provide the desired protection (instructions per manufacturer's guidance)
- Wash hands thoroughly with soap and water when gloves are removed, before eating, and when replacing torn or worn gloves. Soap and water will wash away most spores that may have contacted the skin. Disinfectant solutions are not needed.
- Carefully bag and dispose of any waste, and use a vacuum cleaner with HEPA (High Efficiency Particulate Air) standard filters (as for allergy sufferers). When emptying the vacuum cleaner or changing the filters, wear a disposable FFP3 face mask and gloves.
Can anthrax be deliberately used to infect people?
Yes, there have been successful attempts to produce anthrax as a weapon, focussing on development for airborne dispersal (spread through the air), which would lead to inhalation (breathing in) anthrax. Anthrax spores were deliberately released in the US in 2001, letters containing the spores were sent through the postal system, and resulted in 22 human cases of cutaneous (skin) and inhalation (breathed in) anthrax.
Can anthrax contaminate heroin?
Yes. A large anthrax outbreak in Scotland in 2009-10 was found to be linked to heroin with anthrax in it (contaminated heroin). This outbreak resulted in 119 cases of anthrax among injecting drug users and 14 deaths. The heroin was thought to have been contaminated while it was being transported across Asia and Europe on its way to Scotland.
In 2012, a group of injecting drug users in Europe all caught anthrax around the same time from contaminated heroin. The risk of anthrax exposure for heroin users in European countries (including Ireland) remains. It is important for healthcare workers, drug treatment and harm reduction centres to be aware of the possibility of anthrax infection in injecting drug users to support early diagnosis and treatment.
Symptoms of anthrax after injection (injection anthrax) can include:
- Fever and chills
- A group of small blisters or bumps that may itch, appearing where the drug was injected
- A painless skin sore with a black centre that appears after the blisters or bumps
- Swelling around the sore
- Abscesses deep under the skin or in the muscle where the drug was injected
Injection anthrax symptoms are similar to those of cutaneous anthrax, but injection anthrax can spread throughout the body faster and be harder to recognise and treat than cutaneous anthrax. Skin and injection site infections associated with injection drug use are common and do not necessarily mean the person has anthrax.
Further information on anthrax as a weapon, including ‘Biological threats: a health response for Ireland’, can be found at https://www.hpsc.ie/a-z/emergencyplanning/biologicalthreats/
Last updated: 30 November 2022