How Can Environmental Controls And Personal Protection Prevent Tularemia Infections?

Practical measures to keep you safe and healthy

Introduction

A brief overview of tularemia

Caused by francisella tularensis

The bacterium responsible for tularemia is known as Francisella tularensis, and it is a facultative pathogen. F. tularensis is currently classified as a potential biological warfare agent, and the disease it causes can have up to a 30% mortality rate if not treated in time.¹

A zoonotic disease is transmitted through animals and the environment

A zoonotic disease is an illness that is transmitted only between animals and humans. Therefore, it is important to emphasize that tularemia, also known as 'rabbit fever' or 'deer fly fever,' is not transmissible between humans. You can only get it from contact with infected animals (generally rabbits, hares, and other rodents) or the environment.²

Commonly affects hunters, farmers, and people in rural areas

People at higher risk of contracting this disease include those living in rural areas, farmers, foresters, hikers, hunters, people who are in contact with animals or animal meat, laboratory workers, and veterinarians.³

Importance of environmental controls and personal protection in preventing infections

To maintain your safety, it is important to follow these guidelines:⁴

Environmental controls

• The use of Environmental Protection Agency-registered insect repellents is recommended.
• Do not drink untreated surface water.
• Check for sick or dead animals when mowing the lawn.
• Consider wearing masks while mowing the lawn and during other gardening tasks as a preventive measure against inhaling bacteria.

Personal protection

• It is recommended to wear long pants, long sleeves, and long socks to minimize contact with ticks and deer flies on your skin.
• Act quickly against ticks by removing them with fine-tipped tweezers.
• When engaging in activities that involve handling animals, such as hunting, make sure to wear gloves, especially when handling rodents like rabbits, muskrats, or prairie dogs.
• Cook game meat thoroughly before eating.

Understanding the transmission of tularemia

Main transmission pathways

Direct contact with infected animals

This disease affects not only wild animals. Domestic cats are very susceptible to tularemia, as are hamsters, which have been known to cause outbreaks of this disease. Infections resulting from handling animals can present three specific types of tularemia: glandular, ulceroglandular, and oculoglandular.⁵

Insect bites 

Infections caused by bites from ticks and deer flies typically manifest as ulceroglandular or glandular tularemia.⁵

Inhalation of contaminated particles

You can also contract tularemia by inhaling dust or aerosols contaminated with the bacteria. Although not very common, this can lead to a variant known as pneumonic tularemia, one of the most severe forms of the disease.⁵

Consumption of contaminated food or water

Water is also one of the main sources of transmission. Infected animals can contaminate the water, putting anyone who drinks it at risk of contracting tularemia, specifically oropharyngeal tularemia.⁵

High-risk activities

Hunting, handling wild animals

The bacteria F. tularensis can also be transmitted to humans through the skin when handling tissue from any sick or dead animal. The most common cases occur during hunting or skinning infected rabbits and other rodents. Additionally, eating undercooked meat can result in oropharyngeal tularemia.⁵

Farming and gardening in endemic areas

As we mentioned earlier, humans can acquire tularemia by inhaling dust or aerosols. This infection usually occurs during agricultural or landscaping activities. In many cases, the selected machinery (e.g., tractor, lawn mower) may run over infected animals or carcasses, spreading the disease.⁵

Exposure to water bodies contaminated by animals

Waterborne tularemia outbreaks are not only due to consumption. Risk-related activities involving water include swimming, canyoning, and fishing.⁶

Environmental controls to prevent tularemia

Wildlife management

Reducing rodent and rabbit populations in endemic areas

To control rodents, especially rabbits, fumigation and lethal baits are commonly applied, along with the destruction of burrows, the use of traps, hunting, containment fences, and biological control with RHDV and myxomatosis. The most important consideration before implementing any of these practices is to assess the humanity of the act, as well as the cost-effectiveness and efficiency of each control technique.⁷

Monitoring and controlling animal infections in wildlife populations

To monitor effectively, a system must include the continuous collection, gathering, and analysis of data related to animal health. The key objective is to analyze affected wildlife to detect trends in the environment over a specific period.⁸

The main methods to control diseases shared by wildlife include preventive measures, arthropod vector control, managing host populations through selective or random hunting, habitat management, reproductive control, and immunization. ⁸

Insect control

Tick and fly population management 

Managing tick and fly populations (through the use of insecticides in high-risk areas) is also important. The most commonly used method to control ticks nowadays is entomopathogenic fungi, particularly Metarhizium species. Acaricides, bait boxes, tubes, and pheromones are often used as well. Finding the ideal method requires a specific analysis based on the situation.⁹

For managing fly populations, it's crucial to focus on sanitation, especially manure management, insecticides, and other chemical methods, as well as fly traps.¹⁰

Clearing tall grasses and brush near residential areas to reduce tick habitats

It's essential to clear tall grass, brush, weeds, and leaf litter, as these are ideal moist refuges for ticks. Building a wood chip or gravel barrier to define the territory is also recommended.¹¹

Water safety

Proper treatment of water sources in affected areas to prevent contamination

Proper treatment of water sources in affected areas is necessary to prevent contamination. Some recommended practices include collecting and recycling trash, avoiding fertilizer use before rain, preventing fertilizers from reaching paved areas, and directing yard waste like leaves away from streets using leaf blowers. Additionally, be cautious where you dispose of motor oil—never near or into a storm drain.¹²

Avoid swimming in contaminated lakes or rivers.

Make sure to check the latest inspection results on your local or state health department's website, or even better, visit the site in person if you can. Look for the drain at the bottom of the deep end—it should be easy to see. Also, keep an eye out for lifeguards on duty, and make sure that no chemicals are left out in the open. Your safety is a top priority!¹³

Land management

Safe disposal of animal carcasses to prevent the spread of bacteria

Safe disposal of animal carcasses is necessary to prevent the spread of bacteria. Carcasses and high-risk materials should be disinfected and, if possible, incinerated. Transportation should be carried out using a leak-proof, clean, and disinfected vehicle. It's important to avoid any cuts to the carcass before loading it.¹⁴

Personal protection measures

Protective clothing

It is important to wear appropriate clothing when handling rabbits and other rodents. Keep in mind that these animals can also bite and cause scratches. It is recommended to wear bite-resistant gloves and long sleeves to minimize contact as much as possible.¹⁵

Insect bite prevention

DEET is the most commonly used active ingredient in repellent products. You can use it on both exposed skin and clothing. However, if you apply it to your clothes, be aware that DEET can damage certain synthetic fabrics.¹⁶

A full-body check is also recommended upon returning from potentially tick-infested areas.¹⁷

Safe handling of animals

If you encounter an animal that appears ill, try to avoid direct contact. If it is absolutely necessary, use gloves and wash your hands after contact.¹⁸

Food and water precautions

As mentioned earlier, it is vital to thoroughly cook wild game meat, drink and swim in uncontaminated waters, and also wash fruits and vegetables well.¹⁸

Early detection and medical intervention

Importance of recognizing early symptoms 

The incubation period for tularemia lasts between three to five days, though some people may not show symptoms for up to two weeks.²

It is crucial for the affected person to receive treatment as soon as possible at the first sign of symptoms, as the disease can be fatal. It is important to inform the doctor if you have had direct contact with wild animals or if you have been in an area where tularemia is endemic. Additionally, the doctor should be aware if you have a compromised immune system or are pregnant.¹⁸

Antibiotics as an effective treatment

Tularemia is curable in humans if treated promptly. Antibiotics have proven effective in eliminating the bacteria that cause tularemia. Broad-spectrum antibiotics are used and can be administered in various forms, such as injections or pills. If the condition worsens, other treatments may be necessary.²

Summary

The article explains how to prevent tularemia, a disease caused by Francisella tularensis, which is primarily transmitted through contact with infected animals, insect bites, contaminated particles, or food and water. It mainly affects hunters, farmers, and people in rural areas. Prevention includes controlling rodent populations, especially rabbits, using insect repellents, clearing tall grass, and treating water sources, among other measures. Early detection is vital to prevent complications, as the disease can be fatal. Currently, antibiotics are crucial in treating this illness.

FAQs

How long does it take to cure tularemia?

In adults, Doxycycline is typically used, and the treatment lasts 14 to 21 days. For children, Gentamicin or Ciprofloxacin is used, with treatment lasting 10 to 14 days, while Doxycycline treatment lasts 14 to 21 days.¹⁹

What time of year does tularemia occur?

Tularemia is more common from May to September²⁰