What is anthrax?
Anthrax is a very rare but serious infection caused by the bacteria Bacillus anthracis. The disease is found in animals and humans in most countries of sub-Saharan Africa and Asia, in several southern European countries, in the Americas, and certain areas of Australia. Fortunately, humans are rarely infected. Anthrax bacteria 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 infection is acquired: cutaneous (skin), inhalation and ingestion. In over 95% of cases the infection is cutaneous, generally caught by direct contact with the skins or tissues of infected animals. Inhalation anthrax (known as Woolsorters disease since it was quite common among woollen mill workers in Northern England in the early 20th century) is rare and is caught by breathing in anthrax spores. It was a recognised occupational hazard 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 occurs from ingestion of contaminated meat.
How common is anthrax?
Anthrax is very rare. There has not been a case in Ireland for more than a century. Only a handful of cases have been reported in the UK in the last 20 years. Human infections are more frequent in countries where the disease is commonest in animals, including countries in South and Central America, Southern and Eastern Europe, Asia and Africa.
Are animal hides a risk for contracting anthrax?
Anthrax infections associated with the handling of untanned animal hides are extremely rare.
In countries where anthrax is endemic (for example in Africa and Asia), hides may occasionally be contaminated. Anthrax is a very rare disease amongst livestock in Ireland; no case has been seen for more than a quarter of a century.
Although the risk is extremely low, personal imports of untreated hides may pose a risk for infection. A case of inhalation anthrax occurred in 2006 in America in a man who made drums from dried (but otherwise untreated) animal hides brought in from Africa, and a case in Scotland occurred the same year. Cases of cutaneous anthrax have also followed similar exposures.
How long can you have the infection before developing symptoms?
In general, symptoms usually develop within 48 hours with inhalation anthrax and 1-7 days with cutaneous anthrax.
What are the symptoms?
Early identification of anthrax can be difficult as the initial symptoms are similar to other illnesses.
Cutaneous (skin) anthrax - Local skin involvement after direct contact.
- 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 ulcerates and then 2-6 days later the classical black eschar (scar) develops
- 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 difficulties and shock 2-6 days later. Untreated disease is usually fatal, and treatment must be given as soon as possible to reduce mortality.
Intestinal anthrax is contracted by the ingestion of contaminated carcasses and results in severe disease which can be fatal. This is found in some parts of the world where the value of an animal dying unexpectedly outweighs any fears of contracting the disease.
Can anthrax be treated?
Cutaneous anthrax can be readily treated and cured with antibiotics. Mortality is often high with inhalation and gastrointestinal anthrax, since successful treatment depends on early recognition of the disease, but the disease is treatable if caught early.
Is a person with anthrax a risk to others?
It is extremely rare for anthrax to be spread from person-to-person. Airborne transmission from one person to another does not occur; there have been one or two reports of spread from skin anthrax but this is very, very rare.
Is there a vaccine?
There is a vaccine against anthrax, but it is not approved for widespread use because it has never been comprehensively tested in human trials. 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?
Persons engaged in making drums should only use animal hides that have been processed to reduce the chance of infectious disease transmission. Anyone with ongoing exposure to untreated animal hides should consider adopting the following measures:
- Conduct work in well-ventilated areas that do not exhaust to other work or living areas
- Use disposable gloves when handling hides and cover all cuts, abrasions or broken skin with waterproof dressing. Avoid hand to mouth/eye contact.
- Avoid where possible 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 as 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. A number of countries have attempted to produce anthrax as a weapon, focussing on development for airborne dispersal, which would lead to inhalation of the organism. 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 and inhalation anthrax.
Can anthrax contaminate heroin?
Yes. An extensive anthrax outbreak in Scotland in 2009-10 was found to be linked to contaminated heroin. This outbreak resulted in 119 cases of anthrax among IDUs and a total of 14 deaths. The Final Report into that outbreak concluded that it resulted from the importation of contaminated heroin, contamination probably occurring “somewhere in transit between Afghanistan/Pakistan and Scotland, probably in Turkey”.
A European cluster of anthrax in intravenous drug addicts was identified in 2012 involving cases in multiple countries. The European Centre for Disease Prevention and Control (ECDC) and the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) issued a rapid risk assessment about this cluster and concluded that “The risk of exposure for heroin users in European Union (EU) countries is … still present” indicating that all EU countries should be aware of the possibility of such cases arising in their jurisdiction.
Further information on anthrax as a weapon can be found in the HPSC document on Biological Threat Agents (published 2002). The Department of Health published interim guidelines in 2001 on Protocol for Dealing with a Suspected Anthrax Attack In Ireland.
Last updated: 20 August 2012
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