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สิ่งคุกคามต่อสุขภาพในบุคลากรทางการแพทย์ในโรงพยาบาล

BIOLOGICAL HAZARDS

MODES OF TRANSMISSION

Healthcare workers may be exposed to a variety of biological hazards. As discussed below, effective immunization and infection control programs, as well as appropriate postexposure evaluation and medical management policies, must be established. Common blood-borne pathogens include HIV, hepatitis B and hepatitis C; uncommon pathogens include syphilis, viral diseases, and malaria. Pathogens transmitted via the airborne route include tuberculosis, measles, varicella, and under certain conditions smallpox, hemorrhagic fevers, SARS, and possibly influenza. Droplet-transmitted pathogens include meningococcus, pertussis, H. influenzae, M. pneumoniae, Group A streptococcus, mumps, rubella, adenoviruses, parvovirus and influenza. Infections spread by skin exposure include Herpes simplex, papilloma virus and fungi. Enteric pathogens include hepatitis A, Salmonella, Shigella, and Norovirus. Research institutions may present special challenges, such as those associated with handling animals in research and biological agents that require special facilities. 

INFECTION CONTROL PRACTICES

http://www.cdc.gov/ncidod/dhqp/about.html http://www.cdc.gov/ncidod/dhqp/index.html http://www.cdc.gov/ncidod/dhqp/healthDis.html

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http://www.cdc.gov/ncidod/dhqp/worker.html http://www.cdc.gov/ncidod/dhqp/gl_hcpersonnel.html http://www.cdc.gov/ncidod/dhqp/wrkr_occHealth.html http://www.shea-online.org/ http://www.apic.org//AM/Template.cfm?Section=Home1 http://www.cdc.gov/ncidod/dhqp/gl_environinfection.html http://www.cdc.gov/ncidod/dhqp/gl_isolation.html http://www.cdc.gov/ncidod/dhqp/gl_handhygiene.html

Appropriate training and policies to minimize patient-to-employee and employee-to-patient transmission of communicable disease are essential. Effective surveillance activities should also be in place to prevent transmission of communicable disease and to diminish absenteeism.

Policies and procedures should include:

1. 1)  Thorough preplacement evaluation, including documentation of immunizations, TB surveillance testing, and orientation to communicable disease work restrictions.

2. 2)  Periodic re-evaluation to encourage preventive activity and use of personal protective equipment.

3. 3)  Initial and periodic mandatory training in the use of personal protective equipment and universal precautions.

4. 4)  Periodic review of employee lists to assure adequate numbers and training of employees for respirator use.

5. 5)  Immunization review and updated programs.

6. 6)  Ongoing tuberculosis testing requirements to include employees, volunteers, students, and

   medical staff.

7. 7)  Care of personnel for work-related exposures and illnesses.

8. 8)  Monitoring exposures to infectious disease.

9. 9)  Maintenance of employee health records.

10. 10)  Providing educational sessions and literature encouraging work and personal hygiene.

11. 11)  Establishing work restriction programs to prevent transmission of communicable disease.

Suggested immunizations for health care facility employees

A number of immunizations may be indicated or considered in health care workers depending on the risk of exposure or the infection risk to patients. These vaccinations include:

Diseases for which immunization is strongly recommended – Hepatitis B, measles, mumps, rubella, influenza, varicella, pertussis

Diseases for which immunization/prophylaxis may be indicated – hepatitis A, meningococcal disease

No increased risk among health care workers, but should be current – diphtheria, tetanus

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Special circumstances, including research and animal labs – rabies, Q fever, polio, vaccinia, others as appropriate for circumstances

ftp://ftp.cdc.gov/pub/Publications/mmwr/rr/rr4618.pdf http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5517a1.htm http://www.cdc.gov/vaccines/vpd-vac/varicella/vac-faqs-clinic-hcp.htm

Needlestick injuries

Needlestick injuries remain a significant cause of health care worker injuries. Sharps with engineered safety features should be regularly reviewed, trialed, and implemented where feasible. Needles should not be recapped or broken before disposal. Puncture resistant containers should not be filled to capacity. Needlestick injuries require determination of worker and source (wherever possible) serological status regarding hepatitis B and C, and HIV. Appropriate consents to HIV test the worker and source are necessary, and regulations vary by State. Under special circumstances, some states allow for source patient testing without the permission of the source patient. Recommendations and practices regarding blood-borne exposures change frequently and policies should regularly be reviewed and updated. Generally, serological follow-up of the healthcare worker exposed to HIV, HBV, or HCV should be carried out at baseline, 6 weeks, 3 months, and 6 months following exposure. Current guidance with respect to prophylaxis or early treatment of specific infections should be followed. (See specific bloodborne pathogens below.)

In all cases of confirmed HBV, HCV, or HIV exposure, which include mucous membrane exposure as well as the more common “sharps” exposure, a counseling session with a knowledgeable health care provider should be offered to the exposed employee. Information should be obtained to determine if the employee is a member of a high-risk group. The employee should be advised to report any illness which occurs within the initial six-month period following exposure, particularly skin rashes, fever, malaise, joint pain, muscle aches, enlargement of lymph nodes, and any acute infections. Instructions on the use of condoms or abstinence to prevent sexual transmission of HIV during the six months following exposure should be given. Women of childbearing age should be checked for pregnancy if they elect to take prophylactic medication. Benefit and risk information regarding medications should also be discussed. Information should be provided regarding availability of follow-up counseling and community resources. Standard first aid should be provided for all needlestick injuries, cut and bite wounds, including washing the injury site and applying antiseptic. If the exposure is to mucous membranes (i.e. eyes), copious irrigation should be performed immediately.

Preplacement testing for bloodborne diseases, especially hepatitis C, is a controversial issue. Worker compensation precedent in some states assumes that a health care worker who has contracted a bloodborne disease must have acquired it as a result of an occupational exposure unless there is compelling evidence to the contrary. Preplacement testing, where legal, may serve to protect the employer from future liability as well as making the employee aware of the presence of a potentially debilitating and possibly fatal disease. Early treatment of chronic hepatitis C is another controversial area, and practitioners should consult experts in the field when there are questions regarding evaluation and treatment. Preplacement testing for surface and core antibody to Hepatitis B and for Hepatitis B surface antigen or obtaining records documenting prior adequate Hepatitis B titers is recommended

http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5409a1.htm http://www.cdc.gov/ncidod/dhqp/gl_occupational.html

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http://www.osha.gov/SLTC/bloodbornepathogens/index.html http://www.cdc.gov/niosh/topics/bbp/ http://www.cdc.gov/niosh/docs/2008-101/

Hepatitis B

Percutaneous exposure to HBV-infected blood is associated with a seroconversion risk of 1-6% if a source patient is e-antigen negative, but 22-31% if the source patient is e-antigen positive.
HBV is resistant to drying, ambient temperatures, simple detergents and alcohol, and may survive on environmental surfaces for up to one week.

Workers with reasonably anticipated potential blood and body fluid exposure should, according to federal regulation, be offered vaccination for hepatitis B. Those previously vaccinated for hepatitis B should have documentation of hepatitis B surface antibody response to the vaccine. Hepatitis B surface antibody testing should be carried out among previously vaccinated personnel without such documentation. Because hepatitis B surface antibody titers wane with time without compromising immunity, a negative hepatitis B surface antibody test several years following completion of vaccine does not provide evidence that an individual is a non-responder to the vaccine. Reasonable management of such individuals as a part of the pre-placement evaluation includes a single booster of vaccine, followed 4-6 weeks later by retesting of hepatitis B surface antibody. Those who remain hepatitis B surface antibody-negative should have the vaccine series repeated, with surface antibody testing thereafter. Recommendations for non-responders, low responders, workers who are exposed without completing a series and unvaccinated workers tend to change frequently, so policies should be regularly reviewed and updated. At a minimum, vaccine nonresponders should be tested for the presence of hepatitis B surface antigen, and if positive, educated about treatment options.

HCW who have hepatitis B or C may hesitate to admit that they are infected out of fear that this will restrict their careers. Depending upon institutional policies, those who perform invasive procedures may indeed need to restrict some aspects of their practice, particularly if they have chronic active hepatitis B. However, most healthcare workers can work safely with their infections. Those with chronic hepatitis B also may be unaware that treatment is now available, and OHS can assist with referrals for such treatment.

http://www.cdc.gov/ncidod/dhqp/gl_occupational.html http://www.cdc.gov/vaccines/vpd-vac/hepb/default.htm http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5409a1.htm http://www.cdc.gov/ncidod/diseases/hepatitis/b/index.htm

Human Immunodeficiency Virus (HIV)

Routine patient contact has not been found to increase worker risk of acquiring HIV. Health care workers should be trained, retrained and mandated to follow CDC Standard Precautions Guidelines. Personnel should minimize the risk of exposure to parenteral or mucosal contact with potentially infectious material (blood, sputum, aerosols, and other body fluids). Appropriate personal protective equipment and training should be available and mandated.

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A 0.3% risk of HIV infection following needlestick exposures is commonly quoted. Characteristics that may be associated with higher risk of seroconversion include deep injury, visible contamination of the device with blood, needle placement directly into an artery or vein, or exposure to an individual with elevated viral titers. Risk of seroconversion following mucous membrane exposure has been estimated at 0.09%, based on one seroconversion in six studies.

In addition to following the basic protocol for HIV exposures, the need for prophylaxis with antiretroviral medications should be evaluated on an individual basis by the employee health physician treating the employee, and drugs should be made quickly available (preferably within one or two hours) and provided free of charge to the employee if the employee elects to take them. After the initial baseline HIV antibody is drawn, the employee should receive recall notices for follow-up HIV antibody testing at appropriate intervals for at least 6 months unless the source patient has been identified as not having HIV or another bloodborne pathogen and is not part of a risk group for early HIV infection i.e. active current IV drug user. Informed consent and confidential reporting are key elements of any HIV surveillance activity.

http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5409a1.htm http://www.cdc.gov/hiv/

Hepatitis C

Following percutaneous exposure to infected blood, risk of hepatitis C seroconversion among exposed healthcare workers ranges from 0 to 10%, with an average risk of 1.8%. Infection following mucocutaneous exposure appears to be much less common. Antibodies to HCV may be detected within 5 to 6 weeks of infection, and may persist regardless of whether virus is actively replicating. Most individuals have no acute symptoms.

The management of patients acutely infected with hepatitis C is a topic of current discussion. No hepatitis C vaccine is available, and administration of immune globulin is ineffective. Several studies have demonstrated the efficacy of interferon alpha2b in treating acute hepatitis C. One report has demonstrated long-term viral clearance in 98% of subjects when interferon alfa-2b was begun during acute disease at an average of 89 days following infection. It has been shown that symptomatic patients with acute hepatitis C are more likely to spontaneously clear the virus than are patients with asymptomatic infection. Another study documented spontaneous viral clearance, generally within 12 weeks of symptom onset in 52% of symptomatic acute infections, but no spontaneous viral clearance among patients with asymptomatic acute infection. Given the high cure rates associated with acute therapy, and the toxicities of interferon and ribavirin, there is no role for prophylactic therapy in individuals exposed percutaneously or mucocutaneously to hepatitis C-infected blood or body fluids. Acute therapy should be considered for seroconverters.

http://www.cdc.gov/ncidod/dhqp/gl_occupational.html http://consensus.nih.gov/2002/2002HepatitisC2002116html.htm http://www.cdc.gov/mmwr/PDF/rr/rr5203.pdf http://www.cdc.gov/ncidod/diseases/hepatitis/c/fact.htm

Enteric pathogens

Dietary personnel should have prompt evaluation and treatment of any gastrointestinal disease. Prompt reporting of gastrointestinal illnesses should be required, and re-evaluation prior to return

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to work is essential. HR policies that provide paid sick time for such illness may encourage employee compliance. Good handwashing technique, use of non-latex disposable gloves, and proper training should be encouraged and reinforced during site visits.

Hepatitis A virus is found in serum, stool and liver only during acute infections. IgM antibody identifies acute infection while IgG anti-hepatitis A indicates prior HAV exposure with immunity to recurrent infection. Hepatitis A vaccine may be indicated in certain high-risk settings.

http://www.cdc.gov/ncidod/diseases/food/index.htm

Influenza

An active influenza vaccine program benefits employees, patients, and institutions. Vaccination of health care workers not only reduces the risk of patient exposure to an infected worker (and vice versa) but may also decrease the sickness/absenteeism rate for the institution. Influenza vaccine should be offered to all employees free of charge and strongly encouraged among employees with potential direct patient contact. Multi-pronged influenza vaccination programs including “flu vaccine fairs”, decentralized or unit-based vaccination, coverage of all employee shifts, coupled with assertive education campaigns have been shown to result in influenza vaccine adherence exceeding 70%. Prophylaxis with antiviral medications may be indicated for unvaccinated health care workers during institutional outbreaks.

Standard and Droplet precautions are recommended for healthcare workers caring for patients with influenza. For pandemic influenza, enhanced precautions, including N95 respirators, should be used in accordance with OSHA and CDC guidance. For patients with significant diarrhea, contact precautions should be added. If spray or splatter of infectious material is likely, goggles or face shield should be worn according to Standard Precautions.

http://www.cdc.gov/flu/ http://www.cdc.gov/flu/professionals/acip/index.htm http://www.cdc.gov/flu/professionals/vaccination/index.htm http://www.cdc.gov/flu/professionals/infectioncontrol/index.htm http://www.cdc.gov/flu/professionals/antivirals/index.htm http://www.cdc.gov/flu/professionals/flugallery/index.htm http://www.pandemicflu.gov/index.html

Pneumonia

Current guidelines from the CDC should be consulted to determine the need for pneumococcal vaccine based on the employee’s age, medical history, and potential work and non-work exposures.

Varicella

Employees having direct contact with children or immunocompromised patients should have their varicella immune status documented. For the general public, a positive history of chicken pox in an adult born in the United States is a reliable indicatory of immunity. Employees with negative or unknown histories of varicella should have their immune status determined by a varicella zoster

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virus titer. Employees raised in tropical climates are at greater risk of being susceptible. Varicella-susceptible employees who are exposed to varicella should be restricted from work in patient areas from the tenth day following initial exposure to the twenty-first day post varicella exposure. Institutions may elect to establish a policy requiring immune status documentation at hire, to allow for vaccination of susceptible personnel and minimize furlough time following an exposure. Employees infected with varicella should be restricted from patient work until all lesions are dried and crusted. Immunocompetent employees with localized zoster should be restricted from caring for high-risk patients until lesions are crusted, but may care for other patients as long as lesions are covered. Immunosuppressed employees with localized zoster may have respiratory shedding of virus and should be restricted from patient care until lesions are crusted.

Although not as protective as seroconversion to native varicella, varicella vaccination should be administered for those employees who are not immune. If lesions occur post-vaccination, the affected employee should be restricted from patient care until lesions are crusted. Because immunity from varicella vaccine may wane over time, vaccinated employees may not be fully protected if they are exposed to varicella later in their career. The OHS should maintain a record of immunizations and investigate the medical histories of all exposed workers. While those with natural immunity need no specific monitoring after exposure, workers who are exposed to varicella after receiving the varicella vaccine require special attention. The OHS may test them for the presence of circulating varicella IgG 5 to 6 days after the exposure, and monitor them daily from days 10 to 21 after exposure if IgG is not present. If resources do not allow daily monitoring, furlough from the workplace is another option. If IgG is present, the employee should still be educated that a mild case of varicella is still possible, and workers who experience any skin lesions consistent with primary chickenpox should report to OHS for evaluation. If resources allow, these employees may also benefit from daily monitoring during the incubation period.

The single-dose zoster (shingles) vaccine is indicated for adults over age 60, regardless of varicella immunity history. However it should not be administered to individuals who have undergone the two-dose varicella series.

http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5604a1.htm http://www.cdc.gov/ncidod/dhqp/gl_hcpersonnel.html http://www.cdc.gov/vaccines/pubs/ACIP-list.htm#vacc

Measles, Mumps, Rubella

Healthcare workers should have documented immunity to measles, mumps and rubella (MMR). Proof of immunity should be by a statement of vaccination from a physician or health care facility, documentation of protective titers, vaccination at time of employment without prescreening, or screening followed by vaccination if the employee is negative. MMR vaccine should not be administered during pregnancy and specific instructions should be provided regarding avoidance of conception for at least three months. As a live virus vaccine, MMR should not be administered to individuals with severe immunosuppression. The Advisory Committee on Immunization Practices (ACIP) has published guidelines on the use of MMR vaccine in HIV-infected patients, based on the patient’s age and CD4 count. History of prior rubella disease is not considered acceptable proof of immunity to rubella.

http://www.cdc.gov/mmwr/preview/mmwrhtml/00050577.htm http://www.cdc.gov/mmwr/preview/mmwrhtml/00053391.htm http://www.cdc.gov/vaccines/pubs/ACIP-list.htm

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http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5522a4.htm?s_cid=mm5522a4_e

Pertussis

Several outbreaks of pertussis have occurred among health care workers. Disease is spread by droplets and direct contact, and antibiotic prophylaxis is indicated for workers with close exposures to acutely infected individuals. Prophylactic regimens in common use include erythromycin, trimethoprim-sulfamethoxazole, clarithromycin, or azithromycin. A pertussis vaccine for adults has been approved and is recommended for healthcare workers. The best approach to postexposure management of vaccinated individuals is not clear at this time; it is unknown whether vaccinated individuals may still contract subclinical disease or be contagious to others. It may be reasonable to offer postexposure prophylaxis to vaccinated workers, based upon the time since vaccination, their work setting, home contacts and other risk factors.

http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5517a1.htm

http://www.acoem.org/guidelines.aspx?id=562

Tuberculosis

Tuberculosis poses a threat to health care personnel. Immunization and travel from endemic TB areas occurs on a daily basis. Multiple Drug Resistant Tuberculosis (MDRTB) is a problem in high-risk populations (eg, foreign born, alcoholics, IV drug users, prison inmates, homeless, immunosuppressed and AIDS patients). Health care workers performing bronchoscopies, intubations, respiratory care, and aerosolized pentamidine treatment are at particularly high risk. Each institution should develop a policy that protects workers and patients, and provides for appropriate surveillance and treatment. Two step testing is currently recommended for health care workers at the time of hire, regardless of BCG vaccination history. While the Mantoux TB skin test is still the foundational test for latent TB, new blood assays for M. tuberculosis which measure T-cell activation, e.g., QuantiFERON-TB Gold, which are more specific, but possibly less sensitive, have been approved for use as an alternative to the TB skin test, and may prove especially useful for testing of employees previously vaccinated with BCG.

Screening as well as evaluation and treatment of reactors/converters should follow the most current CDC recommendations. An employee database, with readily available identification of conversions by area of institution should be maintained. Work areas with two or more skin test conversions in a year may have experienced an unrecognized TB exposure, and should be investigated accordingly. As surveillance programs are only helpful if they cover the entire population at risk, compliance with the TB skin testing program should also be monitored and compliance rates by area should be reported regularly to the institutional leadership.

A person with a newly positive PPD should be offered prophylactic therapy. Those with positive TB skin tests (TST) of uncertain duration under the age of 35 should also be offered prophylactic therapy, as should anyone with a positive TST at high risk of activation. Conditions which place individuals at high risk of activation include HIV, silicosis, “old TB” on x-ray with no prior treatment, chronic renal failure, diabetes mellitus, malignancy, nutritional or GI deficiency, and immunosuppression.

Appropriate environmental controls, personal protective equipment and an early high index of suspicion are necessary steps to limit transmission of TB. Effective respirators (N-95 or HEPA) should be available and employees properly fit tested after being medically evaluated for the respirator. OSHA currently requires initial and annual training and fit testing of respirator users.

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Negative pressure rooms should be available and properly utilized in various patient care areas of medical facilities.

http://www.cdc.gov/tb/ http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5417a1.htm?s_cid=rr5417a1_e

Severe Acute Respiratory Syndrome (SARS)

From November, 2002, through July, 2003, 8098 individuals worldwide contracted SARS, a new human respiratory disease caused by a novel coronavirus. The disease, which appeared to be transmitted primarily by droplets and direct contact, spread to more than 1700 healthcare workers. In some hospital settings, primarily because of delayed recognition of the disease, attack rates among healthcare workers were nearly 60%. Worldwide SARS claimed 774 deaths from 2002-2003, with a case fatality rate of 9.6%.

Clinical illness was characterized by an incubation period of about 2-10 days, fever, chills, rigors, headache, malaise, and sometimes diarrhea, followed by lower respiratory tract involvement. While most patients with SARS did not transmit the disease to others, well publicized accounts of “superspreaders” attested to the potential for widespread transmission in certain settings and with certain individuals.

The key step in preventing transmission to healthcare workers is early recognition of disease and proper isolation of potentially infected patients. Numerous accounts have detailed spread of SARS in hospitals when patients were treated for days prior to the recognition that they were infected with the virus. In one such account, it was estimated that a single index patient had potentially exposed 10,000 patients and visitors and 930 hospital staff, triggering a nationwide SARS outbreak in Taiwan. Current CDC guidelines call for various measures to screen patients with respiratory symptoms or atypical pneumonia for SARS, depending upon the current disease epidemiology. The imposition of hand washing and surgical mask donning among symptomatic patients in clinics and acute care hospitals is designed to minimize transmissions in waiting rooms and other settings of respiratory pathogens, including SARS.

http://www.cdc.gov/ncidod/sars/ http://www.cdc.gov/ncidod/sars/guidance/C/index.htm http://www.cdc.gov/ncidod/sars/guidance/C/app2.htm

Agents of Bioterrorism

Occupational and environmental medicine practitioners in medical centers should be involved in institutional initiatives to prepare for bioterrorist attacks. The CDC classifies agents of bioterrorism into three categories. Category A diseases/agents are those which can be easily disseminated or transmitted from person to person; which result in high mortality rates and have potential for major public health impact; which might cause public panic and social disruption; and which required special action for public health preparedness. Category B disease/agents are considered moderately easy to disseminate; result in moderate morbidity rates and low mortality rates; and require specific enhancements of diagnostic capacity and enhanced disease surveillance. Category C diseases/agents include those that could be engineered for mass dissemination in the future due to their availability, ease of production and dissemination, and potential for high morbidity and mortality rates.

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Category A agents include Bacillus anthracis (anthrax), Clostridium botulinum toxin, Yersinia pestis (plague), Variola major (smallpox), Francisella tularensis (tularemia), and the viral hemorrhagic fevers (Ebola, Marburg, Lassa, and Machupo). Category B agents include Brucella species (brucellosis), Epsilon toxin of Clostridium perfringens, food safety threats (Salmonella species, Escherichia coli 0157:H7, Shigella), Burkholderia mallei (glanders), Burkholderia pseudomallei (melioidosis), Chlamydia psittaci (psittacosis), Coxiella burnetii (Q fever), Ricin toxin, Staphylococcal enterotoxin B, Rickettsia prowazekii (typhus fever), viral encephalitis (alphaviruses [e.g., Venezuelan equine encephalitits, eastern equine encephalitis, western equine encephalitis]), and water safety threats (e.g., Vibrio cholerae, Cryptosporidium parvum). Emerging infections such as Nipah virus and hantavirus are considered to be Category C agents.

Agents of bioterrorism vary in their propensity for transmission from person to person. Guidelines addressing infection control in medical center settings, vaccinations, prophylactic therapies and other issues pertinent top medical center preparedness can be accessed at www.bt.cdc.gov.

http://emergency.cdc.gov/bioterrorism/ http://emergency.cdc.gov/bioterrorism/prep.asp

Laboratory and animal handling biosafety

Biomedical research poses unique exposure risks to employees. A team approach with administrative, safety, and engineering personnel is required to ensure that proper ventilation and other primary prevention controls are in place to reduce occupational disease and injury in this setting. Laboratory animal allergy from the respiratory inhalation of sensitizing proteins, as well as through dermal contact, may affect up to 30% of researchers. Zoonotic infections are possible from virtually every laboratory animal species, requiring that occupational and environmental medicine physicians work closely with veterinarians to determine which employees may be at risk for bites and infections, such as rabies, salmonella, and ringworm. Other hazardous exposures may include percutaneous exposures to biologic agents, radioactive isotopes, carcinogens, chemicals, anesthetics, and drugs. Well designed medical monitoring and surveillance programs should be developed in the areas of reproductive hazards, hearing conservation, respiratory protection, immunizations, bloodborne pathogens exposures, zoonoses, emergency medical response, physical and environmental hazards.

An ideal occupational health program for animal facilities starts with hazard identification based on the species used. Administrative controls should be in place to permit animal access only to individuals appropriately trained and enrolled in the occupational health program. The institution must identify which workers are exposed to animal hazards, and provide appropriate education and training..

The animal research facility’s occupational health program should be risk-based. Since all mammalian and bird species pose a risk of occupational allergy, an allergy surveillance program is the foundation of the program. This may consist of a screening questionnaire, prompting further medical evaluation if symptoms are present. Sensitized individuals must be enrolled in a respiratory protection program with appropriate PPE to prevent further exposure, because the risk of occupational asthma in this sensitized population is up to 20%. Alternatively, institutions may elect to enroll all animal workers in a respiratory protection program attempting to prevent initial sensitization.

Some species carry zoonotic diseases which can be prevented through immunization, or detected early through medical surveillance. For these workers, the occupational health program should provide appropriate immunization and/or periodic medical screening exams. Examples include rabies, carried by ferrets, dogs, bats and other species, and coxiella burnettii ( Q Fever) carried by ruminants. Other zoonotic diseases, such as simian herpes B virus carried by certain

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non-human primates, require specialized knowledge to deliver immediate medical care and postexposure prophylaxis, to prevent life-threatening infection in the event of a bite, splash or scratch. The occupational health practitioner caring for primate handlers must understand these risks, and have excellent rapport with the veterinarians and animal facility managers. Education and protocols for bite management must be established and communicated in advance. Exposure management often requires coordination of testing for both the animal and the human involved.

Serum banking, once a mainstay of occupational health programs for animal workers, has proven to be of little utility. While for certain agents or hazards, serum banking may be a compliment to the program, it should not be used as a substitute for regular thoughtful medical evaluation.

http://www.cdc.gov/ncidod/srp/animals/laboratory.html http://www.cdc.gov/od/ohs/biosfty/bmbl5/bmbl5toc.htm http://www.osha.gov/SLTC/laboratories/index.html http://www.cdc.gov/od/ohs/ http://www.nap.edu/catalog/10713.html

International Travel

International travel has become more common for employment, recreation, education, and medical missions. Employees should be evaluated and educated in advance of travel regarding health risks.

Healthcare workers who will be carrying out clinical work in HIV-endemic areas of the world without ready availability of antiretroviral medications should be provided with an initial supply of antiretroviral medications and a method to access sufficient medications for a full 28-day course in the event of bloodborne exposure from an HIV-positive source patient.

Institutions which send healthcare workers to areas of the world where extensively drug resistant tuberculosis (XDR TB) is present, and where existing infection control measures have not been shown to adequately control transmissions, may consider use of BCG vaccination. Institutions which make BCG vaccination available to healthcare workers traveling to such environments should make clear that the vaccine has been associated with varying levels of protection, that protection is by no means complete, and that all other infection control measures must continue to be assiduously followed. Due to its interference with tuberculin skin testing, tuberculosis surveillance among recent BCG recipients must be carried out using the QuantiFERON-TB Gold assay.

Discussion of diseases typically encountered in the developing world, their prevention and treatment can be found at www.cdc.gov/travel. Protective immunization guidelines are published by the U.S. Centers for Disease Control and Prevention (CDC). Post-travel evaluation and/or testing should be performed as necessary, particularly if illness has occurred during or after travel.

http://wwwn.cdc.gov/travel/ http://wwwn.cdc.gov/travel/contentVaccinations.aspx http://wwwn.cdc.gov/travel/contentPresentationsHealthPros.aspx

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http://www.cdc.gov/ncidod/eid/

PHYSICAL HAZARDS

Physical hazards commonly found in healthcare facilities include electrical hazards, noise, slipping/tripping/falling hazards, heat, poor lighting, inadequate ventilation, and working with medical equipment such as lasers and x-ray equipment. Occupational health services should support the development of a comprehensive safety program. The program should include medical surveillance activities, environmental surveillance reports, safety reviews, incidents reports, and review in promotion of safe work practices.

Physical hazards include trauma resulting from being struck by an object, in fall etc., electrocution, ionizing radiation, non-ionizing radiation, including lasers, noise, asphyxiation in confined spaces, and heat and cold stresses resulting from ambient weather or from heating, ventilation, and air conditioning problems. Many healthcare worksites have typical industrial exposure hazards, associated with shop activities, including plumbing, heating/cooling, electric, carpentry tasks, laundry, and housekeeping. Where indicated, surveillance may be necessary for repetitive motion/cumulative trauma disorders, shop safety, vision and hearing protection, and instruction in compliance in the use of personal protective equipment. Healthcare institutions should be instrumental in developing safety programs that incorporate OSHA standards, corporate policies, and best practice guidelines. They should encourage compliance as part of their "corporate culture." These programs should include medical surveillance activities, environmental surveillance reports and review, safety reviews, review of incident reports and mechanisms for employees to report hazardous activities and participate in the development solutions.

http://www.osha.gov/SLTC/etools/hospital/mainpage.html

Laser safety

The growing use of lasers in both inpatient and ambulatory settings has increased the need for comprehensive laser safety programs. ANSI standard Z. 136.3 (1986) addresses a number of safety and specific medical issues pertinent to laser use. A baseline ophthalmology history and screening exam is recommended by ANSI. This may include use of precise visual acuity testing, using visual contrast sensitivity. Exit examinations often include Amsler grid examination, to document normal visual field performance. Proper eye protection should be provided. Local exhaust ventilation and personal protective equipment should be considered for control of exposure to the surgical plume. Administrative and engineering controls may be helpful to decrease the number of potential exposures.

http://www.osha.gov/SLTC/laserelectrosurgeryplume/index.html http://www.osha.gov/SLTC/laserhazards/index.html

Ionizing radiation

Programs should comply with federal and state regulations regarding ionizing and non-ionizing radiation and the radiation safety committee should include personnel from the employee health medical and nursing staff as well as radiology, nuclear medicine, surgery and physical plant workers.

http://www.osha.gov/SLTC/radiation/index.html

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http://www.osha.gov/SLTC/radiationionizing/index.html

Nonionizing radiation (NIOSH)

http://www.osha.gov/SLTC/radiation_nonionizing/index.html

Ergonomic

Ergonomic issues arise in almost all activities performed in healthcare facilities. Of particular concern are back injuries and repetitive motion/cumulative, trauma disorders. Back problems continue to be the leading cause of lost time injuries among healthcare workers. Recent data suggest that the incidence of back injury is highest among nurse aides and exceeds even the incidence rate of back injury in industrial workers. Cumulative trauma is an issue with clerical workers, laboratory personnel, custodial workers and potentially the entire hospital workforce. OHS should work closely with purchasing, administration and safety in the acquisition, implementation and design of facilities and equipment. The establishment of ergonomic committees and surveys and the development of systematic approaches to ergonomic hazards with written programs are essential. Technology has evolved to the point where minimal lift policies are economical, practical and safe in many institutions.

Integrated approaches to safe patient movement and handling are increasingly common in acute care hospitals. Such programs should include identification of high risk areas, assessment of hazards, selection of equipment, training, maintenance, and development of no-lift policies. Use of safe patient handling equipment has been associated with substantial reductions in injuries among acute care hospital personnel.

http://www1.va.gov/visn8/patientsafetycenter/resguide/ErgoGuidePtOne.pdf http://www.osha.gov/ergonomics/guidelines/nursinghome/index.html http://www.cdc.gov/niosh/topics/ergonomics/ http://www.aohp.org/About/documents/GSBeyond.pdf http://www.cdc.gov/niosh/docs/wp-solutions/2006-148/ http://www.cdc.gov/niosh/docs/2006-117/

CHEMICAL HAZARDS

Healthcare workers may be exposed to a wide variety of potentially toxic chemicals. Exposures can occur either during accidents or during normal working conditions. The effects may range from minor skin irritation to possible mutagenic effects, chronic disease (e.g. occupational asthma) or adverse reproductive outcomes. OHS should have access to clinical toxicology, appropriate industrial hygiene monitoring, environmental control methodology, and recommended and/or regulatory exposure levels. Material Safety Data Sheets (MSDS), computerized databases and poison control centers may be helpful in obtaining information regarding chemical exposures.

http://www.cdc.gov/niosh/npg/ http://www.osha.gov/web/dep/chemicaldata/#target

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http://www.acgih.org/sitemap.htm

Many databases are now available to provide toxicologic and other useful information on chemical substances. Extensive research is available through TOXNET. Poison control centers (1-800-222-1222) are often very helpful in providing information on the treatment of occupational chemical exposures. Many states have passed "Right to Know" legislation requiring worker education about hazardous substances in collection of health hazard data. Because employee knowledge of hazards and safe work habits is essential to prevent occupational illness, each institution should develop educational policies to ensure that workers are familiar with potential hazards and encourage workers to follow safe work practices. OSHA's Hazard Communication Standard (CFR 1919.1200) requires employers to make employees aware of hazards to which they may be exposed through the use of labels, material safety data sheets, and training programs. Proper emergency procedures must be developed and effective safety equipment made available. If respirators are required, OHS should ensure that workers are properly trained to use them. Fit-testing, proper care of respirators, and surveillance require input from OHS. MSDS should be readily available at the worksite as well as at Occupational Health. Hazard information should be communicated through labels, formal training programs, and a written hazard communication program. Employee training should encompass the following: 1) How to access and utilize available hazard information (read and interpret labels and MSDS); 2) Identification and characteristics of hazards present at the worksite; 3) Employee protection plan detailing the use of personal protective equipment, safe work practices, and engineering controls. Proper glove and respirators selection should be stressed.

http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=TESTIMONIES&p_id=349 http://www.osha.gov/SLTC/carcinogens/index.html http://www.osha.gov/dts/chemicalsampling/toc/toc_chemsamp.html
http://www.atsdr.cdc.gov/

http://www.atsdr.cdc.gov/MHMI/mmg.html http://toxnet.nlm.nih.gov/

Specific chemical exposures:

Latex Hypersensitivity

Allergic responses to latex materials have been identified as a substantial issue for healthcare providers and their patients. The response is varied and may rarely be fatal. The delayed hypersensitivity reaction (Type IV) appears as an eczematous local contact allergic dermatitis. It is usually not due to latex itself but primarily to chemicals added to accelerate curing of rubber during glove manufacturing. Immediate hypersensitivity (Type I) is a local and systemic allergic response to natural rubber latex protein that is associated with rapid onset of urticaria, which may progress to rhinitis, respiratory symptoms, angioedema or asthma. Exposure leading to these symptoms may occur by direct contact or by inhalation of aerosolized latex. Latex dust may be difficult to eliminate once it has permeated carpeting, furniture and ductwork. Immediate hypersensitivity responses are mediated by IgE, and may be diagnosed with IgE RAST serum testing or (under carefully monitored circumstances) skin prick testing with natural latex. Information about latex allergy should be disseminated to healthcare employees, students, ancillary personnel and patients. Facilities should identify latex containing products (gloves, condoms, catheters, balloons, tourniquets, anesthesia equipment, respirator bellows, airways, etc.) Appropriate evaluation, restrictions and reasonable accommodations if indicated, should be

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provided to the potentially affected employee. OHS staff should know that many other agents cause asthma in health care workers

A latex allergy policy can facilitate the proper establishment of latex safe environments to meet the needs of patients and employees. This policy should address purchasing, admitting, education, latex safe areas and signage, as well as patient care issues. The major latex reduction methods to consider are conversion to powder-free latex gloves, which significantly reduce latex aerosolization, or conversion to non-latex gloves.

http://www.osha.gov/SLTC/latexallergy/index.html http://www.cdc.gov/niosh/topics/latex/

http://www.spinabifidaassociation.org/atf/cf/%7BEED435C8-F1A0-4A16-B4D8- A713BBCD9CE4%7D/2007%20Latex%20Lists.pdf

Disinfectants

Exposure to disinfectants and cleaning solutions is a common cause of chemical injuries among medical center employees, with housekeepers and maintenance workers at greatest risk. Glutaraldehyde irritates skin and mucous membranes and may cause allergic contact dermatitis, rhinitis, and asthma. Perchloracetic acid causes similar problems. Bleach is an irritant and, in high concentrations, may cause burns of the skin, mucous membranes and eyes. The use of soaps in handwashing is a common cause of skin irritation and less commonly contact dermatitis among nursing and medical staff. The recently published CDC guidelines on handwashing emphasize the use of disinfectants and skin protecting lotions to prevent irritant contact dermatitis. Regulatory inventory review is necessary for proper product control and safety.

http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5217a2.htm http://www.steriloxtechnologies.com/PDFs/Guideline_for_Selection_Use.pdf

Ethylene oxide

Ethylene oxide is a colorless gas used to sterilize temperature sensitive, medical instruments. It has a distinctive sweet odor, but the average odor threshold is relatively high. Ethylene oxide is regulated by OSHA as a carcinogen. Medical surveillance is required for employees with exposure over the action level. The area of highest exposure risk is in central sterilization areas, and risk reduction requires engineering controls and continuous or periodic air monitoring (preferably with an alarm system) as well as good work practices. Instruments sterilized with ethylene oxide must be aerated in aeration cabinets before they are used. Ethylene oxide exposure most commonly occurs via dermal absorption or inhalation so appropriate PPE is indicated. Medical surveillance (OSHA) may also be indicated in light of the known association of ethylene oxide with increased spontaneous abortion, mutagenicity, carcinogenicity (stomach, leukemia and other hematopoietic cancers) and neurotoxicity at higher exposure levels. It is unclear whether lower level exposure settings require ongoing medical surveillance. If done, surveillance should focus on the hematopoetic, reproductive, renal, and nervous systems.

http://www.osha.gov/SLTC/ethyleneoxide/index.html

Formaldehyde

Exposure risk areas include autopsy rooms, pathology laboratories and dialysis units. Exposure

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also occurs in endoscopy and surgical facilities. If action levels are exceeded, preplacement and periodic examinations should include baseline and periodic pulmonary, dermal, and hepatic evaluations. PPE (including appropriate gloves) should be available in areas were spills are likely and should include spill absorbent materials and appropriate personal protective equipment.

Odor is not a reliable warning for the presence of formaldehyde, because the ability to smell formaldehyde is quickly extinguished.

http://www.osha.gov/SLTC/formaldehyde/index.html

Glutaraldehyde