People active outdoors, especially in agriculture and forestry, are exposed to health hazards from animals, plants, bacteria, viruses and so on to a greater degree than is the rest of the population.
Plants and Wood
Most common are allergic reactions to plants and wood products (wood, bark components, sawdust), especially pollen. Injuries can result from processing (e.g., from thorns, spines, bark) and from secondary infections, which cannot always be excluded and can lead to further complications. Appropriate protective clothing is therefore especially important.
A comprehensive description of the toxicity of plants and wood products and their components is not possible. Knowledge of a particular area can be acquired only through practical experience—not only from books. Possible safety measures must derive from knowledge of the specific area.
Large Mammals
Using horses, oxen, buffalo, elephants and so on as work animals can result in unforeseen dangerous situations, which may lead to injuries with serious consequences. Diseases transmittable from these animals to humans also pose an important danger.
Infections and Diseases Transmitted by Animals
These constitute the most significant biological hazard. Their nature and incidence varies strongly from region to region. A complete overview is therefore not possible. Table 1 contains a selection of infections common in forestry.
Table 1. Selection of infections common in forestry.
|
|
Cause |
Transmission |
Locations |
Effects |
Prevention/therapy |
|
Amoebiasis |
Entamoeba histolytica |
Person-to-person, ingestion with food (water, fruits, vegetables); often asymptomatic carriers |
Tropics and temperate zone |
Frequent complications of the digestive tract |
Personal hygiene; chemoprophylaxis and immunization not possible. Therapy: chemotherapy |
|
Dengue fever |
Arboviruses |
Aedes mosquito bite |
Tropics, subtropics, Caribbean |
Sickness results in immunity for one year or longer, not lethal |
Control and elimination of carrier mosquitoes, mosquito nets. Therapy: symptomatic |
|
Early summer meningo-encephalitis |
Flavivirus |
Linked to the presence of the ixodes ricinus tick, vector-free transmission known in individual cases (e.g., milk) |
Natural reservoirs confined to certain regions, endemic areas mostly known |
Complications with later damages possible |
Active and passive immunization possible. Therapy: symptomatic |
|
Erysipeloid |
Erysipelotrix rhusiopathiae |
Deep wounds among persons who handle fish or animal tissue |
Ubiquitous, especially infects swine |
Generally spontaneous cure after 2-3 weeks, bacteremia possible (septic arthritis, affected cardiac valve) |
Protective clothing Therapy: antibiotics |
|
Filariasis |
Wuchereria bancrofti, Brugia malayi |
From animal to humans, but also from some types of mosquitoes |
Tropics and subtropics |
Highly varied |
Personal hygiene, mosquito control. Therapy: medication possible |
|
Fox tapeworm |
Echinococcus multilocularis |
Wild animals, esp. foxes, less commonly also house pets (cats, dogs) |
Knowledge of endemic areas necessary |
Mostly affects liver |
No consumption of raw wild fruits; dampen fur when handling dead foxes; gloves, mouth protection Therapy: clinical treatment |
|
Gaseous gangrene |
Various clostridia |
At the onset of infection, anaerobic milieu with low redox potential and necrotic tissue required (e.g., open crushed soft parts) |
Ubiquitous, in soil, in intestines of humans and animals |
Highly lethal, fatal without treatment (1-3 days) |
No known specific antitoxin to date, gaseous gangrene serum controversial Therapy: clinical treatment |
|
Japanese B encephalitis |
Arbovirus |
From mosquitoes (Culex spp.); person-to-person; mammal-to-person |
Endemic in China, India, Japan, Korea and neighbouring countries |
Mortality to 30%; partial cure to 80% |
Mosquito prevention, active immunization possible; Therapy: symptomatic |
|
Leptospirosis |
Various leptospira |
Urine of infected wild and house animals (mice, rats, field rabbits, foxes, dogs), skin injuries, mucous membrane |
Endemic worldwide areas |
From asymptomatic to multi-organ infestation |
Appropriate protective clothing when around infected animals, immunization not possible Therapy: penicillin, tetracycline |
|
Lyme disease |
Borrelia burgdorferi |
Ixodes ricinus tick, other insects also suspected |
Europe, North America, Australia, Japan, China |
Numerous forms of sickness, complicating organ infection possible |
Personal protective measures before tick infectation, immunization not possible Therapy: antibiotics |
|
Meningitis, meningo-encephalitis |
Bacteria (meningo-, pneumo-staphylococci and others) |
Mostly airborne infection |
Meningococci, meningitis epidemic, otherwise ubiquitous |
Less than 10% mortality with early diagnosis and specific treatment |
Personal hygiene, isolate infected persons Therapy: antibiotics |
|
|
Viruses (Poliomyelitis, Coxsackie, Echo, Arbo, Herpes and Varicella viruses) |
Mucous and airborne infection (airways, connective tissue, injured skin), mice are source of infection in high percentage of cases |
Ubiquitous incidence |
High mortality (70%) with herpes infection |
Personal hygiene; mouse prevention Therapy: symptomatic, among varicella effective specific treatment possible |
|
|
Mushrooms |
Mostly systemic infections |
Ubiquitous incidence |
Uncertain prognosis |
Therapy: antibiotics (protracted treatment) |
|
|
Mycobacteria (see tuberculosis) |
|
|
|
|
|
|
Leptospira (see leptospirosis) |
|
|
|
|
|
Malaria |
Various plasmodia (tropica, vivax, ovale, falciparum, malariae) |
mosquitoes (Anopheles species) |
Subtropical and tropical regions |
30% mortality with M. tropica |
Chemoprophylaxis possible, not absolutely certain, mosquito nets, repellents, clothing Therapy: medication |
|
Onchocerciasis Loiasis Dracunculiasis Dirofilariasis |
Various filaria |
Flies, water |
West and Central Africa, India, Pakistan, Guinea, Middle East |
Highly varied |
Fly control, personal hygiene Therapy: surgery, medication, or combined |
|
Ornithosis |
Clamydia psittaci |
Birds, especially parrot varieties and doves |
Worldwide |
Fatal cases have been described |
Eliminate pathogen reservoir, immunization not possible Therapy: tetracycline |
|
Papatasii fever |
Flaviviruses |
Mosquitoes (Phlebotomus papatasii) |
Endemic and epidemic in Mediterranean countries, South and East Asia, East Africa, Central and South America |
Mostly favourable, often long convalescence, sickness leaves far-reaching immunity |
Insect control Therapy: symptomatic |
|
Rabies |
Rhabdovirus |
Bite from infected wild or house animals (saliva highly infectious), airborne infection described |
Many countries of the world, widely varying frequency |
Highly lethal |
Active (including after exposure) and passive immunization possible Therapy: clinical treatment |
|
Recurrent fever |
Borrelia-spirochetes |
Ticks, head and body lice, rodents |
America, Africa, Asia, Europe |
Extensive fever; up to 5% mortality if untreated |
Personal hygiene Therapy: medication (e.g., tetracycline) |
|
Tetanus |
Clostridium tetani |
Parenteral, deep unclean wounds, introduction of foreign bodies |
Ubiquitous, especially common in tropical zones |
Highly lethal |
Active and passive immunization possible Therapy: clinical treatment |
|
Trichuriasis |
Trichuris trichiura |
Ingested from eggs that were incubated 2-3 weeks in the ground |
Tropics, subtropics, seldom in the United States |
Only serious infections display symptoms |
Personal hygiene Therapy: medication possible |
|
Tsutsugamushi fever |
Rickettsia (R. orientalis) |
Associated with mites (animal reservoir: rats, mice, marsupials); infection from working on plantations and in the bush; sleeping outdoors especially dangerous |
Far East, Pacific region, Australia |
Serious course; mortality close to zero with timely treatment |
Rodent and mite control, chemoprophylaxis controversial Therapy: timely antibiotics |
|
Tuberculosis |
Various myco-bacteria (e.g., M. bovis, avium balnei) |
Inhaling infected droplets, contaminated milk, contact with infected wild animals (e.g., mountain goats, deer, badgers, rabbits, fish), wounds, mucous membranes |
Ubiquitous |
Still high mortality, depending on organ infected |
Active immunization possible, chemoprophylaxis disputed Therapy: clinical treatment, isolation, medication |
|
Tularemia |
Francisella tularensis |
Digestive tract wounds, contaminated water, rodents, contact with wild rabbits, ticks, arthropods, birds; germs can also enter through uninjured skin |
Ubiquitous |
Varied forms of sickness; first sickness leads to immunity; mortality with treatment 0%, without treatment appr. 6% |
Caution around wild animals in endemic areas, disinfect water Therapy: antibiotics |
|
Yellow fever |
Viruses |
Bite from forest mosquitoes, which are infected from wild primates |
Central Africa, South and Central America |
Up to 10% mortality |
Active immunization |
Poisonous Snakes
Poisonous snakebites are always medical emergencies. They require correct diagnosis and immediate treatment. Identifying the snake is of decisive importance. Due to the wide range of varieties and territorial particularities, the knowledge necessary for this can be acquired only locally, and for this reason cannot be described in general. Blocking veins and local incisions (only by experienced people) are not undisputed as a first-aid measure. A prompt dose of a specific antidote is necessary. Attention must also be paid to the possibility of a life-threatening allergic general reaction to the antidote. Injured persons should be transported lying down. Do not administer alcohol or morphine.
Spiders
Few poisons have been researched to date. An attempt should absolutely be made to identify the spider (of which knowledge can be acquired only locally). Actually, there are no valid general first-aid measures (possibly administer available antiserums). In addition, what was said about poisonous snakes applies analogously.
Bees, Wasps, Hornets, Ants
Insect poisons have very different effects, depending on the locale. Removing the stinger from the skin (and being careful not to introduce more poison during handling) and local cooling are recommended first-aid measures. The most-feared complication is a life-threatening general allergic reaction, which can be provoked by an insect sting. People allergic to insect poisons should, therefore, carry adrenalin and an injectable antihistamine with them.
Scorpions
After injury, a dose of antidote should absolutely be given. Local knowledge of first aid is necessary.