Friday, January 25, 2013



1.0 Introduction:
Right from time the dispensation of health care services has always been accompanied with one adverse effect or the other occasionally. With the institutionalization of health care, a prominent hazard whose consequence has the tendency of spreading within the health care community emerged and this consequence is nosocomial infection. It is also called hospital acquired infection (HAI) or healthcare associated infection but here for consistency we will adopt the terminology, “nosocomial infection”.

Nosocomial infection can be defined as adverse biological response to pathogenic micro organism’s presence or the presence of its toxin in a patient undergoing treatment that was not manifested or incubated before admission (Garner, Jarvis, Emori, Horan & Hughes, 1996, P.AI; Inweregbu, Dave & Pillard, 2005; WHO, 2002). Operationally, infection that commenced 48hours after admission, within 3 days after discharge or 30 days after operation is regarded as nosocomial infection (Inweregbu, Dave & Pillard, 2005).

Nosocomial infection continues to present challenges to healthcare and patients safety despite the advances in healthcare technology. This is because as state-of-art technologies emerge for the delivery of effective and efficient health care for the population, these technologies involve invasive devices, the hospitals in most developing world is being crowded, patients population is becoming older, increase in immune compromised patients and improper use of antibiotics.
Organisms responsible for nosocomial infections are bacteria, fungi, viruses and parasites (CDC, n.d.).

2.0 Public health and economic burden
In the United States of America, about 1.7million people suffer from nosocomial diseases annually (CDC, 2010). Among these patients; 52,328 are newborns, 417,946 are adults and children in intensive care units, while 1,266,851 are children and adults from other units (CDC, 2010). It is estimated that about 5% of hospitalized patients acquire nosocomial infection in America, while in the European countries, it is about 10% of hospitalized population and recent studies put in between 10-15% (Yinnon et al., 2012; CDC 2010). Dilek, et al (2012) observed that nosocomial infection rate in developing countries is about three to five times higher than the rate in America. A patient with nosocomial infection spends 21/2times longer in hospital accumulating additional cost of £3,000 more hospital bill in Europe (Inweregbu, et al., 2005). They also estimated that 5,000 deaths are due to nosocomial infection annually causing up to one billion pounds to the National Health Service. Study indicated that intensive care units have nosocomial infections prevalence of about 20.6% (Inweregbu, et al., 2005), and blood stream infection forms between 31.5% to 82.4% of intensive care unit nosocomial infection morbidity and mortality (Chang et al., 2011).

3.0 Common sites of infection and responsible organisms
Signs and Symptoms
Mode of Infection
Urinary tract infection (UTI)
  • Escherichia coli
  • Enterococci
  • Pseudomonas aeruginosa
  • Candida species
  • Proteus mirabilis
  • Providencia stuartii
Fever, frequent urination, dysuria and supra public tenderness
Lower respiratory infection or pneumonia
  • Klabsiella species
  • Staplylococcus aureus
  • Pseudomonas aeruginosa
  • Enterobacter species
  • Legionella species
  • Aspergillus species
Cough, high blood temperature and purulent sputum

Inhalation of aerosol or droplet discharges
Surgical site infection
  • Staphylococcus aureus
  • Enteroccoccus
  • Yeast
  • Gram-negative organisms
Can be as for UTI, pneumonia and blood stream infections
Surgical wounds
Bloodstream infection
  • Staphylococcus
  • Euterococus
  • Canadida species
  • Klebsiella pneumoniae
  • Entcrobacter species
  • Canadida species
Fever, chills, malaise, anxiety, nausea, vomiting and others
Inversive techniques
Gastro intestinal infection
  • Clostridium difficile
  • Rotavirus
  • Salmonella species

Eye infection
  • Chlamydia trachomatis
  • Staphylococcus species
  • Neisseria gonorrhoeae
  • Adenovirus typeB
-          Pains in the eye
-          Foreign body sensation
-          Bloody or other coloration of the eye
-          Fever
-          Redness of the eye
-          Excessive watering
Contact infection
Central Nervous System Infections
  • Streptococcus pneumonia
  • Hemophilus influenza
Headache, Nausea vomiting & Light secession  fever
Wounds, foreign bodies, head trauma, neuroinvaside procedures
Airborne & droplet

Other emerging and re-emerging organisms can also cause nosocomial disease. Examples are those resistant to common antimicrobial agents like Methicilin Resistant Staphylococcus Aureus (MRSA), Vancomycin Resistant Enterococcus (VRE), Penicillin Resistant Streptococcal Pneumonia and Sever Acute Respiratory Syndrome (SARS) (Chotani, Roghmann & Peri, 2007, P.535 – 6).

4.0 Mode of transmission
The mode of transmission of nosocomial infection is related to sources of infection. Nosocomial infection can be transmitted from two main sources: exogenous and endogenous sources: Exogenous sources are factors within the healthcare environments including building, plants, devices, instrument, patients and health workers. Endogenous sources are normal flora organisms of a patient. Normal flora organisms could be part of the patient flora before admission and is responsible for primary endogenous infection, while those that become part of the flora during patients stay in the hospital cause secondary infection (Chotani et al., 2007, P.517). Nosocomial infection transmission can occur through airborne, droplets, direct or indirect contact, ingestion or administration of contaminated water, food, medication, intravenous fluids and blood products.

5.0 Risk factors for Nosocomial infection
Host factor, environmental, microbiological and extrinsic factors can constitute risk factors for nosocomial infection (WHO, 2002). Extreme young or old age, nature of illness, poor nutrition, underlying conditions like obesity, abnormal functioning or inadequate ventilators, dusty conditions, wet surfaces and walls can posse danger of nosocomial infection. Water systems can be colonized by legionella organisms, pseudomonas species, Acinobacters and others, while inanimate objects like formite can encourage the spread of VRE or MRSA. Other risk factors are duration of stay in the hospital and use of total parenteral nutrition (Saloojee & Steenhoff, 2001)
Three main microbiological risk factors of nosocomial diseases are the organism’s virulence, ability to survive in the healthcare environment and ability to resist antimicrobial agents, extrinsic factors are medical procedures and chemotherapeutic agents (WHO, 2002).

6.0 Prevention and Control of Nosocomial infection
In every given healthcare setting the existence of an integrated arrangement that would involve infection control department in conjunction with other units like the microbiological laboratory, staff health services, pharmacy and Data/computer units is vital to surveillance and prevention of nosocomial infection. An infection control committee should be formed, where the infection control officer would either chair or be the secretary to the committee. The committee organizes surveillance activities, collect data on exposures, antibiotic use, pathogenic isolates and molecular finger printing, antimicrobial resistant organisms and so on. The committee should draw a check list on hygiene practices among the health workers, organize training and monitor the implementation in the wards. Infectious disease control rounds that adopted check list and monthly report on nosocomial disease situation in a hospital unit is associated with a significant decline in nosocomial infection in that unit (Linnon et al., 2012). This is also consistent with the observation that education of health worker on good hygiene and aseptic techniques proved successful but unfortunately is not sustainable (Saloojee & Steenhoff, 2001). In a related study device associated nosocomial infection was reduced on the application surveillance procedures in a hospital (Dilek et al., 2011).
This is mainly where the Environmental Health Personnel should make an impact as the infection control officer/personnel. The committee should designate environmental health officers to survey the hospital plants, environment and instruments for efficient functioning and hygiene purposes and report to it. Where necessary the infection control officer should make adequate arrangement to secure the abatement of nuisance detected and ensure regular flushing and cleansing of water systems.
 Other important components of nosocomial infection control activities include hand washing, isolation, microbal agent control and immunization.
Hand washing by the healthcare personnel is one of the most effective means of preventing nosocomial infection in the healthcare facilities. The hands of health workers are always inhabited by normal flora organisms (e.g. Staphylococci species and micrococci) which can also extend to the deeper layers of the skin and transient organisms (like Klebsiella – Enterobacter and Acinetobacter). Normal flora organisms can be dangerous to immuno compromised patients or patients with inserted prolonged foreign object. Thorough hand wash with warm water and detergent substantially reduces microbal colonization of health workers hand. Facilities for hand washing should be located at proximate points as possible. Unfortunately health workers neglect this important procedure, and studies indicated the physicians are the most negligent professional group in this regard and compliance is about 40% of the time in most health institutions (Chotani et al., 2007, P.541). The reason for poor practice of hand wash is the fact that many health workers suffer from a complex Saloojee & Steenhoff described as “Omo-syndrome” – that is a feeling of being super neat and sterile (Saloojee & Steenhoff, 2001).
Isolation is meant to break the chain of transmission of pathogens from source to susceptible person. Health workers, patients or visitors could be source of infection. There are two types of isolation: standard and transmission based isolation. Under standard isolation everybody fluid or skin abrasion is considered infectious. Use of protective devices like masks, glove, cleaning equipment and linen, environmental control and cohorting patients are advised.
Transmission based isolation is implementation of standard precautions plus measures specific to the transmission mode. For airborne infection; private room isolation and negative pressure room and for droplet infection; private room isolation or cohorting of patients should be practiced, while private isolation or cohorting patients will be used for contact infection (Chotani et al., 2007, P.453).
Immunization of health worker is essential in some instances in the case of infection that is vaccine preventable. Some organisms can cause infection both at community level and at hospital level. Diphtheria, Hepatis A & B, influenza, measles and chickenpox immunization should be given to the health workers depending on the risk they face in their occupational setting.
Another important measure for the control of nosocomial infection is antibiotic control in health institutions. Antibiotic is the second most used class of drugs in hospital setting and study has shown that 40% of the times, antibiotics were not properly used. Improper use of these drugs leads to the emergence of anti-microbial bacteria and drug reaction. So it is important that an antibiotic policy that will control the use of the drug evolves in a hospital.

7.0 Conclusion:
Nosocomial infection cases are increasing throughout the world and the situation is more pronounced among developing countries. The rate of nosocomial infections in a hospital varies according to the unit, with intensive care units having the highest rate than other units in a hospital, present invasive medical devices, hospital environment, poor personal hygiene of health workers, age and immune level of patients are factors that predisposes people to nosocomial infection. Continuous integrated infection control activities, surveillance, immunization of health workers, isolation and antibiotic use control policies are vital measures towards the control of nosocomial infection in a health facility.

CDC (n.d.). Health – associated infections (HAI). Retrieved from
CDC (2010). The burden. Retrieved from
Chang, Y-J., Yeh, M-L, Li, Y-C, Hsu, C.Y., Lin, C-C., Hsu, M-S. & Chiu, W-T (2011). Predicting hospital acquired infection by scoring system with simple parameters. PLOS ONE, 6(8), e2317. Doi:10-1371/Journal.pone.0023137.
Chotani, R. A., Roghmann, M. & Peri, T. M. (2007). Nosocomial infections. In Nelson, K. E. & Williams, C. M. (editors). Infectious disease epidemiology. Theory and practice (2nd Ed.). Sudbury Massachusetts Jones and Bartlat Publishers.
Dilek, A., Ulger, F. Esen, S., Acar, M., Leblebicioglu, H. & Rosenthal, V.D. (2011). Impact of education and process surveillance on device – associated health care -associated infection rates in a Turkish ICU: findings of International Nosocomail Infection Control Consortium (INICC) Balkan Med. J., 29, 88-92. Doi: 10.51513/balkanmedj.2011.028
Garner, J.S., Javis, W.R., Emori, T.G., Horan, T.C., Hughes, J.M. (1996). CDC definitions for nosocomial and applied epidemiology: principles and practice. St Louis:Mosby.
Inweregbu, K. & Dave, J. & PiHard, A. (2005). Nosocomial infections. Coutin Educ Anaesth Crit Care Pain, 5(1), 14-17. Doi:10-1093/bjaccp/mki006
Saloojee, H & Steenhoff, A. (2001). The health professional’s role in preventing nosocomial infections. Postgraduate Medical Journal, 77, 16 -19. Doi: 10.1136/pmj.77.903.16.
WHO (2002). Prevention of hospital – acquired infections. A practical guide (2nd edition). Retrieved from
Yinnon, A. M., Wiener-Well, Y., Jerassy, Z., Dor, M. Freund, R., Mazouz, B. & Benenson, S. (2012). Improving implementation of infection control guidelines to reduce nosocomial infection rates: pioneering the report card. Journal of Hospital Infection, 81(3), 169-176. Dio: 10.1016/j.jhin.2012.04.011: