Health care workers practicing outside the United States face unique health hazards, including infectious disease risks associated with patient contact or handling clinical specimens. Any type of health care worker working in clinical areas or handling specimens may be at risk, including physicians, nurses, ancillary clinical staff, trainees (for example, students on international rotations), researchers, and public health workers.
Health care workers can be exposed to infections spread through blood and bodily fluids (such as HIV or hepatitis B) or through airborne or respiratory droplet routes (such as tuberculosis [TB] or influenza). Risks vary depending on the duties of the worker, the geographic location, and the practice setting. Of note, health care workers working overseas can have increased risk of exposure to patients with certain uncommon, highly pathogenic, or emerging infectious diseases such as extensively drug-resistant tuberculosis (XDR-TB), Middle East respiratory syndrome (MERS), and Ebola virus disease.
Risks encountered while performing medical work outside the United States can be due to multiple factors, including:
Health care workers regularly provide care in a range of extreme circumstances, which may be characterized by: limited or absent medical and public health infrastructure; lack of fundamental hygiene supplies (such as soap and water for handwashing); increased infectious disease transmission; extreme environmental conditions; and high levels of violence. In 2016, there were 158 attacks against aid workers; 101 were killed.
Because of these increased risks and consequences of severe disease or injury, adequate prevention and preparation are essential. Health problems for the health care worker can have serious implications, both for the person and for those who depend on the health care worker for provision of health care. Detailed instructions on how to prepare for travel or work in developing countries or humanitarian environments is covered in detail in other sections, but additional key considerations for the health care worker include:
In addition to vaccinations specifically indicated for the country visited and routine age-appropriate vaccines, all health care workers should be up-to-date on all recommended vaccinations for employment in health care settings. These include vaccinations (or documented immunity) for the following:
For hepatitis B, postvaccination serologic testing for antibody to hepatitis B surface antigen (anti-HBsAg) is recommended. Health care workers without documented response to vaccination should receive 1 more additional dose of hepatitis B vaccine followed by anti-HBsAg testing to assess protection.
Regular screening for latent TB infection with tuberculin skin test or interferon-γ release assay is recommended for health care workers at increased risk of TB exposure. Testing before and after travel should be considered when the provider is working in a country with a high prevalence of TB infection or in a setting of high TB exposure, such as in prisons, refugee camps, and health facilities (see Chapter 4, Tuberculosis). Routine vaccination of health care workers with bacillus Calmette-Guérin (BCG) is not recommended in the United States; however, BCG vaccination may be considered for some health care workers who will work in settings with high TB transmission risk and a high prevalence of strains resistant to isoniazid and rifampin.
Baseline testing for HIV and hepatitis C is not routinely recommended, although it should be considered if risk of exposure will be high and reliable testing will not be available locally in the event of an exposure. Inactivated polio vaccine (given as an adult booster dose) or meningococcal vaccine may be indicated for specific locations experiencing high incidence or outbreaks of these infections.
Health care workers should consistently follow standard precautions and, if possible, apply other precautions (contact, droplet, or airborne) as needed. For details, guidelines, and training materials on standard precautions and personal protective equipment (PPE), see https://www.cdc.gov/hai/prevent/ppe_train.html. PPE, including gloves, gowns, aprons, surgical masks, fit-tested N95 respirators, and protective eyewear, may be necessary to achieve personal protection. Workers untrained in infection-control practices should not participate in patient care or activities with risk of exposure to infectious materials. Specialized PPE and infection-control techniques might be indicated for certain infections that pose high risk to health care workers, such as MERS, avian influenza, and Ebola virus (see disease-specific websites at www.cdc.gov for the most up-to-date epidemiology and infection control recommendations).
Health care workers should be properly trained for all anticipated procedures, considering the locally available equipment. Health care workers should maintain strict safety standards, even if local practices are less stringent. Needlestick injuries are a common mode of percutaneous exposure to bloodborne pathogens, and practices known to increase risk of needlestick injuries, such as recapping syringes or using needles to transfer a bodily fluid between containers, should be avoided whenever possible. Safety-engineered medical devices and biosafety equipment such as sharps containers might not be available. Local infection-control practices and supplies should be determined in advance. If the local supply of PPE is questionable, bringing one’s own supply can be important.
Although some airborne or respiratory droplet–transmitted infections are vaccine preventable (such as measles, seasonal influenza, and varicella), vaccines are not routine or available for many others, including TB, MERS, and pneumonic plague. TB is a particular concern for health care workers working overseas in high-incidence areas, and BCG vaccination might be considered for health care workers going to areas with high risk of exposure to multidrug resistant–TB.
Since equipment and facilities for airborne isolation are limited or unavailable in many countries, bringing a personal supply of PPE including N95 respirator masks might be prudent. However, identifying the situations where their use is indicated can be difficult, especially when TB is highly prevalent and isolation of patients is suboptimal. Enhanced PPE recommendations may apply for emerging respiratory pathogens, such as MERS or avian influenza.
Health care workers are at risk for numerous infections transmitted through blood or body fluids via percutaneous, mucous membrane, or nonintact skin exposures. These include bloodborne pathogens such as HIV, HBV, and HCV. The risk of HIV transmission is approximately 0.3% after a percutaneous exposure to HIV-infected blood and approximately 0.09% after a mucous membrane exposure. Health care workers who have received hepatitis B vaccine and have developed immunity to the virus are at virtually no risk for infection. Based on limited studies, the estimated risk for HCV transmission after a needlestick or cut exposure to HCV-infected blood is approximately 1.8%. Other bodily fluids that may transmit HIV and hepatitis viruses include cerebrospinal fluid, synovial fluid, pericardial fluid, pleural fluid, peritoneal fluid, amniotic fluid, semen, and vaginal secretions. Saliva, urine, sputum, nasal secretions, tears, feces, vomitus, and sweat are not considered infectious for HIV and HCV unless they are visibly bloody. Numerous other infections have also been transmitted to health care workers via blood or bodily fluids, including many that are uncommon or not endemic to the United States, such as viral infections (including Ebola virus, dengue), parasitic infections (including malaria), and brucellosis.
Typically, exposures occur as a result of percutaneous exposure to contaminated sharps, including needles, lancets, scalpels, and broken glass (from capillary or test tubes). Infection risk is considered increased after percutaneous exposures to larger blood volumes (visible blood on the injuring device, hollow-bore needles, deeper injuries, or procedures that involved direct cannulation of an artery or vein). Skin exposures to potentially infectious bodily fluids are only considered to be at risk for bloodborne pathogen infection if there is evidence of compromised skin integrity (for example, dermatitis, abrasion, or open wound). Higher circulating viral load in the source patient is also thought to increase the risk of transmission, and this can be of particular concern in resource-poor settings where treatments for HIV and viral hepatitis are limited.
Health care workers with occupational exposures to blood or bodily fluids should perform the following steps immediately:
PEP after percutaneous and mucous membrane exposures to potentially infectious bodily fluids from patients with known or potential HIV infection is recommended to reduce the chance of transmission. A number of medication combinations are available for PEP (see the Updated US Public Health Service Guidelines for the Management of Occupational Exposures to HIV and Recommendations for Postexposure Prophylaxis at http://aidsinfo.nih.gov/guidelines).
The decision of whether or not to initiate PEP must weigh numerous factors. These include the timing, nature, and source of the exposure; regimen choice as affected by drug availability; the exposed person’s medical history; potential drug interactions; and the possibility of exposure to a drug-resistant strain. Expert consultation is important when considering PEP. When expert advice is not immediately available, the National Clinicians’ Postexposure Prophylaxis Hotline (PEPline) can be reached toll-free at 888-448-4911 (11 am to 8 pm Eastern Time daily) for assistance in managing occupational exposures to HIV and HBV and HCV (http://nccc.ucsf.edu/clinician-consultation/pep-post-exposure-prophylaxis).
Other considerations when initiating HIV PEP include the following:
Other potentially infectious exposures in the source material might require specific interventions. For example, if the health care worker is not a documented serologic responder to hepatitis B vaccination or is incompletely vaccinated, postexposure testing of the source patient and health care worker may be indicated, as well as PEP with hepatitis B immune globulin and vaccination.
Postexposure testing and counseling are important follow-up measures for exposed health care workers, whether or not HIV or HBV PEP have been administered. This may include:
Henry M. Wu, Alan G. Czarkowski, Eric J. Nilles