Standard Precaution in Nigeria's Healthcare Industry. A Report on the Need for Universal Safety Precautions in the Nigerian Health Sector
Rezension / Literaturbericht 2019 89 Seiten
2.1 Nosocomial infection
2.1.1 Types of nosocomial infections
2.1.2 Epidemiology of nosocomial diseases
2.1.3 Pre-disposing factors to nosocomial infection
2.1.4 Mode of transmission of nosocomial infections
2.2 Standard precautions and Infection Control of Hospital – Acquired infections Standard (or Universal) Precautions
2.2.1 Components (or Methods) of Standard Precaution
2.2.2 Contributory factors that influence non-adherence to standard precaution
2.2.3 Challenges of the Standard (or Universal) Precautions
2.3 The Healthcare Institution in Nigeria and Its structure
2.4 Other Infection Control Approaches
2.5 Studies on knowledge, compliance, resource availability and barriers to standard precaution (summary of the discussion)
In 2014, there was wide spread panic all over the west coast of Africa from Liberia to Guinea, from Nigeria to Sierra Leone as a result of the re-emergence of Ebola, a viral hemorrhagic disease. According to the Online New Telegraph report (2017) titled “Preventing re-emergence of Ebola”, the relative low knowledge of the disease in some countries (in addition to other factors) had facilitated the spread of the viral disease within these African States. More importantly, the Nigerian case may be said to be particularly unique.
In response to the call for action by the Ministry of Health (MoH), the Nigerian public had quickly adopted some precautionary measures, “People used face masks, hand gloves, hand sanitizers, refused to even shake hands with or hug acquaintances and friends.” Unfortunately, it seemed that while the general public (even the least educated) had started taking measures against the contagion, a highly significant part of the population was left vulnerable. One of such grievous consequence led to the death of Dr. Stella Adadevoh (1956-2014), who had to make the ultimate sacrifice to avert a major pandemic similar to the death plague in Europe. Dr. Stella Adadevoh had correctly diagnosed the Liberian, Patrick Sawyer as the first case of Ebola at First Consultant Hospital, Lagos despite his insistence that he has a bad case of Malaria. “Dr. Adadevoh tried to create an Isolation area, despite the lack of protective equipment, by creating a wooden barricade outside Patrick Sawyer’s door.”The rest of the painful account rests in the annals of history.
The World Health Organisation adduced the devastating effect of the outbreak to unpreparedness and lack of prompt response; low awareness (or education) among health professionals about the disease and poor public enlightenment campaign (New Telegraph, 2017).Unfortunately, few month following the cessation of the spread of the virus, all educational campaigns namely in the media regarding safety and hygiene among the general populace have been discontinued.
There still continues to be a general apathy with respect to promoting even the most basic precautionary measures both in the healthcare institution and the general populace.
The historical narrative cited above highlights the unequivocal role of standard precautionary measures to all stakeholders involved in the hospice industry particularly health workers in relation to the management and control of diseases.
In today world, there exists an overwhelming body of literature with respect to some of common causes of infection including viruses, bacteria, and fungi among others. The rising cases of virulence and pathogenicity of these infection-causing micro-organisms in healthcare facilities has led to a consistent increase in hospital -acquired infections. These facts therefore require policies that ensure that healthcare workers and the general public are not unduly exposed to potentially preventable infections (Naidoo, 2017).
The recent attention on diseases acquired in healthcare facilities in both developing and developed countries reflects the relevance of improving infection control measures. Healthcare professionals, patients and the general public are regularly being exposed to a multitude of bacterial, viral and fungal pathogens in out-patient and in-patient care settings. These infections have been termed nosocomial infections (also referred to as hospital-acquired infections or healthcare-associated infections (WHO, 2013).
Epidemiological research has implicated In-patient facilities particularly intensive care units (ICUs) as being the ‘epicentre’ of hospital acquired infections (Naidoo, 2017). These risks however have also been extended to various outpatient facilities such as waiting areas, clinics and pharmacies.
Indeed, the healthcare-associated infections have led to many reports of patient mortality and morbidity as well as rising healthcare costs.
2.1 Nosocomial infection
The term “Nosocomial” is used for any disease acquired by patient under medical care (Krishna, 2018). It is any clinical infection that was either present or was in its incubation period when the patient entered the hospital (Nautiyal et al., 2015). It has been regarded as one of the most contributing factors affecting the patients during the hospital visit and has also become one of great cause for concern for the healthcare professionals (Nautiyal et al., 2015). Notably, it is transmitted in a clinical setting during which an incubation period follows. These infections may later enter their symptomatic phase after discharge from the hospital.
Brusaferro et al. (2015) described healthcare-associated infections as the type of infections caused by prolonged hospital stay. These infection types have been implicated as major risk factor for serious health issues which may result in mortality. Matter-of-factly, in a WHO study conducted in different parts of the world, reports indicated that in North America and Europe 5%-10% of all hospitalizations resulted in nosocomial infections, while Latin America, Sub-Saharan Africa and Asia show more than 40% hospitalizations with nosocomial infections (WHO, 2013; Obiero et al., 2015). As aforementioned, countries in the sub-Saharan region are most affected by these infections.
Several definitions of nosocomial infections have been put forward in line with a 2013 WHO report namely:
- A nosocomial infection is one that occurs in a patient in a hospital or other healthcare facility in whom the infection was not present or incubating at the time of admission.
- A nosocomial infection is one acquired in hospital by a patient who was admitted for a reason other than that infection.
- Infections that occur more than 48 hours after admission are usually considered nosocomial.
- This includes infections acquired in the hospital but appearing after discharge as well as occupational infections among staff of the facility.
- Nosocomial infections may also be considered either endemic or epidemic.
In addition, some researchers believe that the definition of nosocomial infection should also include asymptomatic patients. For instance, an asymptomatic patient may be considered infected if these pathogens are found in the body fluids or at a sterile body site, such as blood or cerebrospinal fluid (Murray et al., 2005).
At this juncture, it is important to stress that certain category of diseases may not be considered as nosocomial. There include: (1) infections that were present at the time of admission and become complicated, nevertheless pathogens or symptoms change resulting to a new infection; (2) The infections that are acquired trans-placentally due to some diseases like toxoplasmosis, rubella, syphilis or cytomegalovirus and appear 48 h after birth (Festary et al., 2015).
2.1.1 Types of nosocomial infections
National Healthcare Safety Network with Center for Disease Control (CDC) for surveillance has classified nosocomial infection sites into 13 types (with 50 infection sites, based on biological and clinical criteria). Some of the infections based on their biological sites include urinary tract infections (UTI), surgical and soft tissue infections, gastroenteritis, meningitis and respiratory infections (Raka et al., 2006; Duque et al., 2007; Khan et al., 2015; Healthline, 2018).
Of the well-documented agents of nosocomial infection, it is said that bacteria are responsible for about ninety percent infections, while protozoans, fungi, viruses and mycobacteria are less contributing compared to bacterial infections (Gatermann et al., 2005).
Typical agents that are usually involved in hospital-acquired infections include Streptococcus spp., Acinetobacter spp., enterococci, Pseudomonas aeruginosa (P. aeruginosa), coagulase negative staphylococci, Staphylococcus aureus (S. aureus), Bacilluscereus (B. cereus), Legionella and Enterobacteriaceae family members including Proteus mirablis, K. pneumonia (Klebsiellapneumonia), Escherichia coli (E. coli), Serratia marcescens. Out of these enterococci, P. aeruginosa, S. aureus and E. coli play a major role (Horan et al., 2008).
184.108.40.206 Some commonly found HAI:
- Methicillin-resistant Staphylococcus aureus (MRSA) is a major category of nosocomial pathogens worldwide. It was found that the patients with MRSA infection had a long length of stay (LOS) before infection and were more likely to receive antimicrobial therapy. It is due to increased use of antibiotics, such as ceftazidime, cefsulodin, fluoro-quinolones and co-amoxiclav (Graffuner, 2002). MRSA can spread in the following ways such as increased skin-to-skin contact, compromised skin (cuts or abrasions), crowding, contaminated surfaces and items, and lack of cleanliness [aaos, 2018].
- Neonatal infection: Among pediatric group, the newborn represent the most affected populations, especially the neonates getting hospitalized in the neonatal intensive care unit (NICU) where there is more use of antimicrobial drugs, medical devices among others. The improper maturation of immune system of the child increases the risk of acquiring nosocomial infection. At birth, the newborns babies, especially premature babies and low birth weight neonates are not having more effective structural barriers, endogenous microbial flora and of matured immune system. The newborn babies are also affected by number of therapeutic procedures that provide an environment for pathogenic organism to infect the neonates and making them susceptible to nosocomial infections; following like intubation, total parenteral nutrition, ventilation, central venous catheters, peripheral intravenous lines, venipuncture and urinary catheters. These factors had led to about 40% of all neonatal deaths in the developing countries (Mohammad, 2014). The most common neonatal infections are pneumonia followed by blood stream infection, skin infection, surgical site infection, eye infection, urinary tract infection, oral cavity infection, upper respiratory tract infection and gastroenteritis. The most common pathogenic microorganism isolated from neonates was S. aureus followed by S. epidermids, Streptococci, E. coli, Pseudomonas,Enterococci, Klebsiella, and very less was Proteus ( Kasim et al., 2014).
- Clostridium difficile Infection
A Clostridium difficile infection is a type of infection caused by bacteria that is affecting the digestive system. It is commonly affecting people who are being treated with antibiotics. The symptoms caused by Clostridium difficile infection may be mild to severe and these include: painful abdominal cramps, diarrhea, and high fever. It can also lead to life-threatening complications such as severe swelling of the bowel from a build-up of gas. The spores of the Clostridium difficile bacteria can spread through the human body in faeces and they can survive for many weeks, and also sometimes months, on objects and surfaces. By touching a contaminated object or surface and then touching the mouth or nose can lead to ingestion of the bacteria.
The Clostridium difficile bacterium usually does not affect healthy people. But usually the antibiotics interfere with the natural balance of bacteria in the gut that provide protection against Clostridium difficile infection. Some antibiotics when used in high doses or for a prolonged time period will increase the chance of developing a Clostridium difficile infection. Antibiotics can cause alteration in the normal levels of bacteria found in the gastrointestinal tract. If there are fewer bacteria present in the gastrointestinal tract, Clostridium difficile bacteria can have the chance to thrive and produce toxins, which can cause damage to the bowel and cause diarrhea. Clostridium difficile is a major cause of antibiotic associated with diarrhea and colitis problems. The incidence of this infection is increasing in the hospitals worldwide, which is due to the consequence of the widespread use of broad-spectrum antibiotics. Hospital-acquired Clostridium difficile infection is associated with the use of not only the antimicrobial, but also due to laxative use, advanced age, proton pump inhibitors use, anticancer drug use, renal dysfunction, and with gastrointestinal surgery (Marra et al., 2007).
- Catheter-associated urinary tract infections (CAUTIs)
Catheter-associated urinary tract infections (CAUTIs) are representing the most common type of nosocomial infection and thereby are a major health concern due to its frequent recurrence and complications. These infections are usually caused due to the pathogenic organisms like Escherichia coli and Proteus mirabilis. Indwelling urinary catheters are the standard medical devices which are utilized in both hospital and nursing home settings for relieving the problems of urinary retention and urinary incontinence. The insertion of indwelling catheter into the bladder increases the chance of the patient to UTIs, and these devicesare acting as initiation site of infection by induction of opportunistic organisms into the urinary tract. The majority of these urinary pathogens are from fecal contaminants, skin residents from the patient's or microflora that are colonizing the periurethral area. The possible modes of bladder entry during CAUTIs are extraluminal (66%), where organisms are ascending from the urethral meatus along the catheter urethral interface. Organisms can also gain entry into the bladder intraluminally (34%), where the bacteria can enter into the bladder due to the manipulation of the catheter system (Jacobsen et al., 2008).
- Hemodialysis associated infections (HeAIs)
Patients those receiving hemodialysis for long period are significantly at greater risk of hospital-acquired infections than the population in general hospital. This greater risk is reflecting impairment in immune system, more frequent hospitalizations, and also need for vascular access. The most common HAIs in this patient population are urinary tract infections and bloodstream infections. Urinary tract infections (UTIs) were found to be most common nosocomial infection in chronic hemodialysis patients that is accounting for about 47% of all infections in this patient population. When compared, the UTIs were more common in chronic hemodialysis patients (4.2/1, 000 patient-days) than the non-chronic hemodialysis patients (0.7/1,000 patient days). In chronic hemodialysis patients, the pathogens found were Candida spp and enterococci (D'Agata et al., 2013). Patients with end-stage renal disease (ESRD) undergoing dialysis are also at greater risk for bloodstream infection (BSI). This type of infection is representing the main cause of morbidity, along with increasing the cost and hospitalization. Impairment in immune system of body due to renal dysfunction, co-morbidities, malnourishment are increasing the virulence, the adherence properties of hospital bacteria as well as the weakening of protective anatomical barriers due to repeating intravascular procedure required for hemodialysis process, representing the main reasons for the prevalence of bloodstream infection in these patient population.
Earlier studies are suggesting that the vascular access for hemodialysis process is the major risk factor for bacteremia in patients with ESRD. The infection risks were found to be less when the vascular access occurred through arteriovenous graft or fistula and more when it occurred through the central venous catheter (CVC), either permanent or temporary. Chronic dialysis patients are having risk for infections caused by nosocomial multidrug resistant (MDR) pathogens showing reduced susceptibility to many antimicrobials drugs. Hence, empirical administration of such antimicrobials may result in chances of morbidity, mortality and cost to the health care system (Fysaraki et al., 2013).
- Vancomycin-resistant Enterococci (VRE) infection in healthcare setting
Enteroccocci are bacteria that are normally found in the human intestines and in the female genital tract and are often found in the environment. These bacteria can often cause infections. Vancomycin is an antibiotic that is used to treating some of the drug-resistant infections caused by enterococci. There are some chances that the enterococci have become resistant to this drug and so called as vancomycin-resistant enterococci (VRE). Most VRE infections occur in hospitals. VRE often spread from person to person by the contaminated hands of caregivers. VRE can also be spread directly to people after touching surfaces that are contaminated with VRE. VRE does not spread through the air by coughing or sneezing. The following categories of populations are at increased risk for becoming infected with VRE: such as population previously treated with the antibiotic vancomycin or other antibiotics for long periods of time, those who are hospitalized, particularly when they receive antibiotic treatment for long periods of time. Populations with weakened immune systems, those undergone surgical procedures such as abdominal or chest surgery, those contacted for some time with medical devices such as urinary catheters or central intravenous (IV) catheters, those who are colonized with VRE (CDC, 2018).
- Gastrointestinal endoscopy associated infections
Gastrointestinal endoscopy is a procedure in which a doctor is able to see the inner lining of the digestive tract. This examination is performed by using an endoscope which is a flexible fiber-optic tube having a tiny TV camera at the end. The camera is connected to either an eyepiece for direct viewing or to a video screen that can display the images on a color TV. The endoscope allows for diagnosis of gastrointestinal (GI) disease as well as treatment (emedicinehealth, 2018).
Following the adoption of the current guidelines, reports on the transmission of bacterial infection from endoscopes has been rare, which were found to be effective in eliminating microorganisms. Earlier studies states that a total of 84 cases of endoscopy-related transmission of Salmonella species in patients were reported between 1974 and 1987. Forty-five cases of endoscopic transmission of Pseudomonas species were reported between 1974 and 1993. The chances for the growth of bacteria in the moisture-rich conditions owing to improper reprocessing of endoscope have been revealed to be highly crucial to the disease transmission. It was found that in some instances, an unsterilized irrigation water bottle which is attached to the endoscope was also identified as a source of infection. More so, due to lack of cleaning and drying of the air-water and/or the elevator channels of duodenoscopies some cases of transmission of Pseudomonas infection had resulted. A few cases of endoscopic transmission of Helico-bacterpylori were found which were related to inadequate reprocessing of endoscopes and biopsy forceps.
Currently, there is literature that emphasize that current reprocessing guidelines have been shown to be adequate in eradicating mycobacteria and inactivating Clostridium difficile spores. (ASGE, 2018).
- Nebulizers-associated infections
A nebulizer is a small machine that changes the liquid medicine into a mist form. By sitting with the machine and we breathe in through a connected mouthpiece. Then medicine goes into the lungs as we take slow, deep breaths for about 10 to 15 minutes. It is easy and pleasant to breathe the medicine into the lungs in this way. In cases of asthma, COPD, or another lung disease, the doctor prescribes medicine that has to be taken using a nebulizer. Bronchodilators, corticosteroids, antibiotics, anticholinergic and mucolytic agents can also be administered through a nebulizer. There are two different types of nebulizers: pneumatic jet nebulizers and ultrasonic nebulizers. P. aeruginosa was isolated from four of 22 tested nebulizers. This was further confirmed by sero- and phage-typing, and by arbitrarily primed polymerase chain reaction (AP-PCR). Earlier data had provided evidences for the co-relation between P. aeruginosa as a cause of infection and the contamination of the nebulizers. It was found that by changing the nebulizer mouthpieces every 24 h and also when sterilized between patients, there was no more occurring contamination, and the outbreak was stopped (Cobben et al., 1996).
- Organ transplant
Organ transplantation is a procedure done surgically for replacing a failing, diseased organ with a healthy donor organ, such as a liver, kidney, heart or lung. Donor organs are accessed from deceased donors, which is always the case in heart transplants, or from the living donors, which usually happens in liver, kidney and rarely, lung transplants. Organ transplantation is the last option for a person with a failing or diseased organ. In children, it is usually due to a birth defect in the organ, such as the heart. In adults, the need for organ transplant may be as a result of diseases such as cancer, or could be damage to the organ over time due to other conditions, such as heart disease, high blood pressure, or diabetes. Usually, medications are tried first, or changes in diet and lifestyle are preferred for treatment of disease (Pfizer, 2018). The most commonly occurring complication is bacterial infection after solid organ transplantation. It is commonly found in organ transplantation which involves the abdominal cavity, such as pancreas or pancreas transplantation, and less occurring in heart transplant recipients. The sources, clinical characteristics, antibiotic resistance and clinical outcomes vary according to the time of onset after transplantation. Most of the bacterial infections developing during the first month after transplantation are hospital acquired, and also there is high incidence of multidrug-resistant bacterial infections. The higher incidence of complications from bacterial infection in the first month post-transplantation may be associated with high morbidity. The infections are caused commonly by S. aureus, enterococci, gram-negative enteric and non-fermentative bacilli. Opportunistic bacterial infections may also occur frequently between months two and six after transplantation. The most frequent developing opportunistic infections in organ transplant recipients are Listeria monocytogenes and Nocardia spp. After month six, solid organ transplant patients commonly develop community-acquired bacterial infections, mainly urinary tract infections by E. coli and S. pneumoniapneumonia (Cervera et al., 2012).
- Bloodstream infections
Line removal should be considered if the line is no longer needed; if the infection is caused by S aureus, Candida species, or mycobacteria; if the patient is critically ill; if the patient fails to clear bacteremia in 48-72 hours; if symptoms of bloodstream infection persist beyond 48-72 hours; and if noninfectious valvular heart disease, endocarditis, metastatic infection, or septic thrombophlebitis is present (Zaoutis and Coffin, 2008). Antibiotics with coverage against Gram-positive and Gram-negative organisms, including Pseudomonas, should be empirically started and then tailored according to susceptibility pattern of isolated organisms. Antifungal therapy (e.g. fluconazole, caspofungin, voriconazole, amphotericin B) in some cases is added to empiric antibiotic coverage. Antiviral therapy (e.g. ganciclovir, acyclovir) can be used in the treatment of suspected disseminated viral infections.
Duration of therapy depends on several factors, including isolated pathogen, retention of catheter, or presence of complications (endocarditis, sepsis). For most bacterial organisms, the duration of therapy is 10-14 days after blood cultures become negative.
Initial empiric antibiotic therapy should be broad and later on streamlined based on results of examination and cultures of sputum, endotracheal suction material and bronchial lavage wash. The choice of empiric antibiotic coverage should take into consideration the risk for multidrug-resistant (MDR) pathogens. Risk factors for MDR include antimicrobial therapy over the past 90 days; current hospitalization of 5 days or more; high frequency of antibiotic resistance in the community, or hospital and immunosuppression (American Thoracic Society Documents, 2005). No clear consensus has been reached as to the duration of antimicrobial therapy for ventilator-associated pneumonia (VAP). Many experts treat for 14-21 days. However, shorter course of antibiotic therapy (about 1 week) may be adequate therapy for some cases. Antiviral medications against influenza have been used to treat symptomatic patients and patients with immunodeficiency or chronic lung diseases to limit morbidity and mortality.
- Urinary tract infection
To avoid the persistence and recurrence of infection, the indwelling catheters should be avaoided if possible. It was found that in few cases, the removal of catheter has resulted in spontaneous resolution of bacteriuria or asymptomatic cystitis. Empiric antibiotic and antifungal therapy should be done to avoid the major complications, including pyelonephritis, renal damage, and bloodstream infections. Duration of therapy may be controversial. Most experts have recommended a minimum 10-14 days therapy for children with sepsis, pyelonephritis, or urinary tract abnormalities (Medscape, 2018).
- Surgical-site infection
Surgical-site infections (SSIs) should be managed with a combination of surgical care and antibiotic therapy. Antibiotic coverage should be modified once culture results are available. Severe infections such as streptococcal gangrene and extensive tissue necrosis need aggressive surgical intervention. For these kinds of infections, antibiotics alone may not work (Medscape, 2018).
- Other healthcare-associated infections
Rotavirus gastroenteritis is a self-limited disease and only needs supportive care. Medical management should focus on preventing dehydration. Treatment is not necessary for asymptomatic carriers of Clostridium difficile. For those who have mild symptoms, discontinuance of antibiotics alone may result in resolution of symptoms. For those who have more severe diarrhea, oral metronidazole is the preferred treatment. Oral vancomycin is reserved for treatment failure with metronidazole. Clinical improvement is usually seen within 2 days of initiating therapy, and duration of treatment is usually 10 days.
2.1.2 Epidemiology of nosocomial diseases
Nosocomial Infections have been known to negatively impact the health and socio-economic well-being globally. It poses economic challenges to countries affected (Blot et al., 2014).
It has been estimated that the prevalence of HCAI in developed and developing countries is 7.6% and 10.1% respectively (Allegranzi et al, 2011; World Health Organization, 2011; Ogoina et al., 2015) while the incidence of nosocomial infections in developed countries vary between 5-10%, while in developing countries the ratio is reported up to 25% (Blot et al., 2014).
The United States (US) Centre for Disease Control and Prevention estimated that annually approximately 1.7 million hospital associated infections caused or contributed to the deaths of 99000 Americans each year. Furthermore, surveys of healthcare facilities in Europe estimate that up to 25 000 deaths occur annually from nosocomial infections (Pollack, 2010). Recent data published in the New England Journal of Medicine in 2014 showed that one in 25 patients developed at least one hospital-acquired infection (Magill et al., 2014).
Naidoo (2017) reported that in South Africa, approximately one in seven patients entering a healthcare facility were at high risk of acquiring nosocomial infections. Of these patients approximately 80% acquire the following infections: Lower respiratory tract infections, Urinary tract infections, Bloodstream infections, Post-surgical infections.
The WHO revealed that worldwide, about 40% of Hepatitis B and C Virus infections and 2.5% of HIV infections to healthcare workers (HCWs) were attributable to occupational sharps exposures, which are mainly preventable (WHO, 2002). For instance: Hepatitis B virus (HBV): the risk of acquiring HBV infection from occupational exposure depends on the frequency of percutaneous and per mucosal exposures to blood or body fluids containing blood (Thomas et al., 1993). Although percutaneous injuries are among the most efficient modes of HBV transmission, percutaneous exposures probably account for only a minority of HBV infections among HCWs. In several investigations of nosocomial hepatitis B outbreaks, most infected HCWs could not recall an overt percutaneous injury (Garibaldi et al., 1972). However, in some studies, up to one-third of infected HCWs recalled caring for a patient who was HBsAg-positive (Callender et al., 1982).
In addition, HBV has been demonstrated to survive in dried blood at room temperature on environmental surface for at least one week. Thus, HBV infections that occur in HCWs with no history of occupational exposure or occupational percutaneous injury might have resulted from direct or indirect blood or body fluid exposures that inoculated HBV into cutaneous scratches, abrasions, burns, other lesions, or mucosal surfaces (Francis et al., 1981).
Because of the high risk of HBV infection among HCWs, routine pre-exposure vaccination of HCWs against hepatitis B and the use of standard precautions to prevent exposure to blood and other potentially infectious body fluids have been recommended since 1980s (CDC, 1982).
Compliance to standard precautions is low in public health facilities, especially in resource-limited settings such as Nigeria, which further predispose HCWs to the risk of infection (Okechukwu et al., 2012).
Sagoe-Moses et al. noted that occupational safety of HCWs is often neglected in low-income countries in spite of the greater risk of infection due to higher disease prevalence, inadequate supply of personal protective equipment (PPE) and limited organizational support for safe practices(Sagoe-Moses et al., 2001).
Needle stick injuries have been shown to be the commonest (75.6%) mechanism for occupational exposure in a Nigerian teaching hospital (Okechukwu et al., 2012). These injuries are usually under-reported for so many reasons, which include stigma that could be associated with an eventual infection with HIV in the affected HCW. There is no immunization for HIV and HCV, thus the most effective prevention is through regular practice of the standard precautions.
The U. S. Bureau of Labor Statistics (1998) reported that for people aged 44 and under, the primary cause of loss of life in the U.S. was not due to heart disease or cancer, but to causes as common as injuries. To this end, injuries kill an average of 142,000 Americans and require an estimated 62.5 billion dollars in medical attention each year (U. S. Bureau of Labor Statistics, 1998). Thisis close to three people dying and over 170 people sustaining a disabling injury every 10 minutes (National Safety Council, 1999). Every year more than 80,000 Americans are permanently disabled as a result of injury to the brain or spinal cord. Therefore, these unintentional injury understandably represent a serious public health concern, and hence, the increasing focus on nosocomial infections.
2.1.3 Pre-disposing factors to nosocomial infection
Infections in the healthcare centres have been known to exist since the inception of hospital themselves. The hospital is without doubt the best avenue for patients to receive care regarding their ailment. It is also undoubtedly, the ‘hotbed’ of myriads of infections as large number of sick assembles under a single roof could easily facilitate the transmission of infectious disease from one patient to another. The consequence is often increased incidences of mortality and morbidity from the health centres.
There is increase body of literature on the occupational hazards of the hospital environment. This is more true considering that during outbreaks healthcare workers (HCWs) are likely to suffer from nosocomial transmissions in their lines of duty (Owolabi et al., 2016).
Age play an important role in predicting the prevalence of nosocomial infections. In fact, there is a significant relationship between increased age and predisposition to nosocomial infections (Özdemirand Dizbay, 2015). According to a study by Özdemir and Dizbay (2015); the incidence of nosocomial infections gradually increases in patients over 65 years age population. Predisposition to infections in this age group is a result of impaired host defense, underlying chronic diseases, long-term hospitalization, steroids and immunosuppressive therapies and malnutrition (Uzun, 2003; Blot et al., 2014).
Furthermore, , low immunity of body, surgical procedure, lack of cleaning facilities, overcrowding of people have also been implicated as possible causes of many hospital-associated infections (Nautiyal et al., 2015).
Summarily, some of the factors known to facilitate the spread of nosocomial infections include:
Low body immunity in patients; patient of advanced age; patients suffering from diabetes; immunosuppressive patients; patients undergoing treatment with chemotherapeutic drugs; catheterization, intravenous therapy, surgical procedures; improper ventilation in operation theatre and wards; overcrowding of hospital; lack of proper cleaning facilities; lack of knowledge about spread of infections; intensive care unit of the hospital; indiscriminate use of antibiotics; Improper hand washing by the patient and hospital staff may increase the risk. Hospital stay for a long time can increase the risk, for example, admission for complex or multiple illnesses. Operations and surgical procedures – the length and type of surgery can also impact; invasive procedures from surgical procedures or the use of equipment such as urinary catheters, intravenous drips and infusions, respiratory equipment and drain tubes. ; the hospital can introduce infection into the body system, for example, surgical procedures, use of equipment such as urinary catheters, intravenous (IV) drips and infusions, respiratory equipment and drain tubes. Furthermore, the incisions (surgical cuts), wounds, burns and ulcers are also more prone to infection.
2.1.4 Mode of transmission of nosocomial infections
Nosocomial pathogens can be transmitted through person to person, environment or contaminated water and food, infected individuals, contaminated healthcare personnel’s skin or contact via shared items and surfaces (Khan et al., 2015). Some of these pathogens have also been implicated in the rising cases of hospital – acquired drug resistance include methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, Pseudomonas aeruginosa and Klebsiella pneumonia and Clostridium difficile among others(Khan et al., 2015).
In the healthcare facilities, some of well-documented nosocomial infections have been known to be transmitted through the following modes (Giuseppina, 2013; Naidoo, 2017):
- Droplet transmission
- Airborne transmission
- Contact transmission (direct or indirect)
Droplet transmission: Droplets greater than five microns in diameter are dispersed via coughing, sneezing, talking or during the performance of procedures such as suctioning or bronchoscopy. Due to their relatively large size they travel only distances of two metres or less (Giuseppina, 2013). Organisms commonly associated with droplet transmission are: (1) Respiratory viruses (e.g. influenza, parainfluenza virus, adenovirus, respiratory syncytial virus, human metapneumovirus) (2) Bordetella pertussis (3) Streptococcus pneumoniae: the most common cause of bacterial pneumonia (4) Neisseria meningitidis: associated with an aggressive form of bacterial meningitis
Small pathogens of less than five microns in diameter are transmitted via coughing or sneezing. These particles travel greater distances and remain in the air for longer periods of time. They are also most likely to reach the alveoli as compared to larger particles and are therefore associated with increased pathogenicity.
Organisms commonly associated with airborne transmission are:
- Mycobacterium tuberculosis
- Rubella virus (German measles)
- Varicella-zoster virus (chickenpox/shingles)
Airborne transmission can be further categorised into obligate or preferential airborne transmission.
- Obligate airborne transmission refers to pathogens that are transmitted only by deposition of droplet nuclei under natural conditions (e.g. pulmonary tuberculosis).
- Preferential airborne transmission refers to pathogens that can initiate infection by multiple routes, but are predominantly transmitted by droplet nuclei (e.g. measles, chickenpox).