Lassa fever primary prevention
Jump to navigation
Jump to search
|
Lassa fever Microchapters |
|
Diagnosis |
|---|
|
Treatment |
|
Case Studies |
|
Lassa fever primary prevention On the Web |
|
American Roentgen Ray Society Images of Lassa fever primary prevention |
|
Risk calculators and risk factors for Lassa fever primary prevention |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Ammu Susheela, M.D. [2]
Overview
There is no vaccine to prevent Lassa fever. Primary transmission of the Lassa virus can be prevented by avoiding contact with Mastomys rodents, especially in the geographic regions where outbreaks occur. When caring for patients with Lassa fever, further transmission of the disease through person-to-person contact or via nosocomial routes can be avoided by taking preventive precautions against contact with patient secretions.
Primary Prevention
- Primary transmission of the Lassa virus from its host to humans can be prevented by avoiding contact with Mastomys rodents, especially in the geographic regions where outbreaks occur. Putting food away in rodent-proof containers and keeping the home clean help to discourage rodents from entering homes. Using these rodents as a food source is not recommended. Trapping in and around homes can help reduce rodent populations. [1]
- When caring for patients with Lassa fever, further transmission of the disease through person-to-person contact or nosocomial routes can be avoided by taking preventive precautions against contact with patient secretions (together called VHF isolation precautions or barrier nursing methods). Such precautions include wearing protective clothing, such as masks, gloves, gowns, and goggles; using infection control measures, such as complete equipment sterilization; and isolating infected patients from contact with unprotected persons until the disease has run its course.
- No vaccine against Lassa fever is currently available, though development is underway. The Mozambique virus closely resembles Lassa fever, while lacking its deadly effects. This virus is being considered for possible use as a vaccine.
- The use of standard precautions is recommended with all patients in a healthcare environment.[2] This includes a minimum level of standard precautions for use with all people regardless of their infection status, routine handwashing practices, safe handling and disposal of used needles and syringes, and intensifying standard precautions. It also includes VHF isolation precautions when needed. Click here to view the PDF version of the CDC Infection Control for Viral Haemorrhagic Fevers.
Rodent Control
- Prevents rodents from entering houses
- Storing grains and other food in rodent proof containers
- Disposal of garbage far from home
- Having cats as pet at home
- Maintaining clean household
Handling Suspected Cases
- In an outbreak situation, several cases occur around the same time. They may be grouped together, and there may be person-to-person transmission. An initial diagnosis of a Lassa fever can be made based on the signs and symptoms.
- Suspecting a Lassa fever during a non-outbreak situation in a single case is more difficult. The early symptoms of Lassa fever include high fever and headache. These are also symptoms for many infections seen at the health facility. Most people who present with fever do not have Lassa fever. Their fever is more often caused by malaria, typhoid fever, dysentery, severe bacterial infection or other fever-producing illnesses usually seen in the area.
- The health worker probably will not suspect a Lassa fever until more severe signs develop and the patient does not respond to recommended treatment for other illnesses. However, health workers should be aware of the possibility of Lassa fever in a non-outbreak situation. As soon as a Lassa fever is suspected, VHF isolation precautions should begin. This will help reduce the number of people exposed to the infection.
- Isolating the patient will restrict patient access to health facility staff trained to use VHF isolation precautions. Establish a barrier between the patient and uninfected patients, other health facility staff, and visitors.
Handling Equipment and Samples
- Disinfection kills almost all bacteria, fungi, viruses, and protozoa. It reduces the number of microorganisms to make equipment and surfaces safer for use. When Lassa fever is suspected in the health facility, all medical, nursing, laboratory and cleaning staff should disinfect:
- Hands and skin after contact with a VHF patient or infectious body fluids.
- Gloved hands after contact with each VHF patient or after contact with infectious body fluids (when gloves cannot be changed).
- Thermometers, stethoscopes and other medical instruments after use with each patient.
- Spills of infectious body fluids on the walls and floors.
- Patient excreta and containers contaminated by patient excreta.
- Reusable supplies such as protective clothing and patient bedding.
- Used needles and syringes.
Transporting Specimens Within the Hospital/Institution
- Specimens should be placed in a durable, leak-proof secondary container for transport within a facility. To reduce the risk of breakage or leaks, do not use any pneumatic tube system for transporting suspected virus specimen.
- Packing and shipping infectious substances must be performed by people trained and certified in compliance with DOT or International Air Transport Association requirements.[1]
Bleach Preparation
- Two strengths of solution are recommended.
- 1:10 bleach solution is a strong solution used to disinfect excreta and bodies. It is also used to prepare the 1:100 bleach solution.
- 1:100 bleach solution is used to disinfect surfaces, medical equipment, patient bedding, reusable protective clothing before it is laundered, rising gloves between contact with each patient, rinsing gloves, apron and boots before leaving the patient's room, disinfecting contaminated waste for disposal.
- The dilutions mentioned pertain to a starting concentration of 5% active chlorine, so the 1:10 solution is 0.5% and the 1:100 is 0.05%.
- These solutions must be prepared new each day as they lose their strength after 24 hours.
Waste Disposal
- Direct, unprotected contact during disposal of infectious waste can result in accidental transmission of Lassa fever. For this reason, all contaminated waste produced in the care of the patient must be disposed of safely. All non-reusable items should be destroyed so they cannot be used again. Burning should be carried out at least daily.
- Liquid waste, including patient excreta, can be disposed of in an isolated latrine or toilet set aside for VHF cases. Burning is the recommended method for disposal of other VHF-contaminated waste. A safe and inexpensive disposal system can be made by using an incinerator or a pit for burning. Use fuel to accelerate the burning and ensure that all waste is completely destroyed.
Burial Practice
- There is risk of transmission in the health facility when a patient dies because the bodies and body fluids of deceased VHF patients remain contagious for several days after death. Family and community members are also at risk if burial practices involve touching and washing the body.
- Burial should take place as soon as possible after the body is prepared in the health facility. Health facility staff should prepare the body safely and instruct families on what is and is not safe.
- To prepare the body, protective clothing is recommended per usually with a second pair of thick rubber gloves. The body and the area around it is sprayed with 1:10 bleach solution. The body is placed in a “body bag” (mortuary sack) and it is closed securely. The body bag is sprayed with 1:10 bleach solution. The body is then transported to the burial site as soon as possible. Any person who must touch or carry the body during transport should wear the same protective clothing as is worn in the isolation area. The grave should be at least 2 meters deep. Viewing the body is not possible and the burial ceremony should be limited to family only. The interior of the vehicle where the body was carried should be rinsed with 1:10 bleach solution.
Community Education
- Community education and involvement is an important part of the prevention of the spread of Lassa fever.
References