2.1. Central line-associated bloodstream infections (CLABSI)

CLABSIs are deadly nosocomial infections with the death incidence rate of 12%–25% [8]. Catheters are placed in central line to provide fluid and medicines but prolonged use can cause serious bloodstream infections resulting in compromised health and increase in care cost [9]. Although there is a decrease of 46% in CLABSI from 2008 to 2013 in US hospitals yet an estimated 30,100 CLABSI still occur in ICU and acute facilities wards in US each year [10].

2.2. Catheter associated urinary tract infections (CAUTI)

CAUTI is the most usual type of nosocomial infection globally [11]. According to acute care hospital stats in 2011, UTIs account for more than 12% of reported infections [12]. CAUTIs are caused by endogenous native microflora of the patients. Catheters placed inside serves as a conduit for entry of bacteria whereas the imperfect drainage from catheter retains some volume of urine in the bladder providing stability to bacterial residence [11]. CAUTI can develop to complications such as, orchitis, epididymitis and prostatitis in males, and pyelonephritis, cystitis and meningitis in all patients [12].

2.3. Surgical site infections (SSI)

SSIs are nosocomial infections be fall in 2%–5% of patients subjected to surgery. These are the second most common type of nosocomial infections mainly caused by Staphylococcus aureus resulting in prolonged hospitalization and risk of death [13]. The pathogens causing SSI arise from endogenous microflora of the patient. The incidence may be as high as 20% depending upon procedure and surveillance criteria used [14].

2.4. Ventilator associated pneumonia (VAP)

VAP is nosocomial pneumonia found in 9–27% of patients on mechanically assisted ventilator. It usually occurs within 48 h after tracheal incubation [15]. 86% of nosocomial pneumonia is associated with ventilation [16]. Fever, leucopenia, and bronchial sounds are common symptoms of VAP [17].

3.1. Bacteria

Bacteria are the most common pathogens responsible for nosocomial infections. Some belong to natural flora of the patient and cause infection only when the immune system of the patient becomes prone to infections. Acinetobacter is the genre of pathogenic bacteria responsible for infections occurring in ICUs. It is embedded in soil and water and accounts for 80% of reported infections [18]. Bacteroides fragilis is a commensal bacteria found in intestinal tract and colon. It causes infections when combined with other bacteria [19]. Clostridium difficile cause inflammation of colon leading to antibiotic-associated diarrhea and colitis, mainly due to elimination of beneficial bacteria with that of pathogenic. C. difficile is transmitted from an infected patient to others through healthcare staff via improper cleansed hands [19]. Enterobacteriaceae (carbapenem-resistance) cause infections if travel to other body parts from gut; where it is usually found. Enterobacteriaceae constitute Klebsiella species and Escherichia coli. Their high resistance towards carbapenem causes the defense against them more difficult [20]. Methicillin-resistant S. aureus (MRSA) transmit through direct contact, open wounds and contaminated hands. It causes sepsis, pneumonia and SSI by travelling from organs or bloodstream. It is highly resistant towards antibiotics called beta-lactams [20].

3.2. Viruses

Besides bacteria, viruses are also an important cause of nosocomial infection. Usual monitoring revealed that 5% of all the nosocomial infections are because of viruses [21]. They can be transmitted through hand-mouth, respiratory route and fecal-oral route [22]. Hepatitis is the chronic disease caused by viruses. Healthcare delivery can transmit hepatitis viruses to both patients and workers. Hepatitis B and C are commonly transmitted through unsafe injection practices [20]. Other viruses include influenza, HIV, rotavirus, and herpes-simplex virus [22].

3.3. Fungal parasites

Fungal parasites act as opportunistic pathogens causing nosocomial infections in immune-compromised individuals. Aspergillus spp. can cause infections through environmental contamination. Candida albicans, Cryptococcus neoformans are also responsible for infection during hospital stay [22]. Candida infections arise from patient’s endogenous microflora while Aspergillus infections are caused by inhalationof fungal spores from contaminated air during construction or renovation of health care facility [23].

5.1. Environment

Poor hygienic conditions and inadequate waste disposal from health care settings.

5.2. Susceptibility

Immunosupression in the patients, prolonged stay in intensive care unit, and prolonged use of antibiotics.

5.3. Unawareness

Improper use of injection techniques, poor knowledge of basic infection control measures, inappropriate use of invasive devices (catheters) and lack of control policies [25]. In low income countries these risk factors are associated with poverty, lack of financial support, understaffed health care settings and inadequate supply of equipments [5].

6.1. Microflora of patient

Bacteria belonging to the endogenous flora of the patient can cause infections if they are transferred to tissue wound or surgical site. Gram negative bacteria in the digestive tract cause SSI after abdominal surgery.

6.2. Patient and staff

Transmission of pathogens during the treatment through direct contacts with the patients (hands, saliva, other body fluids etc.) and by the staff through direct contact or other environmental sources (water, food, other body fluids).

6.3. Environment

Pathogens living in the healthcare environment i.e. water, food, and equipments can be a source of transmission. Transmission to other patient makes one more reservoir for uninfected patient [22].

7.1. Transmission from environment

Unhygienic environment serves as the best source for the pathogenic organism to prevail. Air, water and food can get contaminated and transmitted to the patients under healthcare delivery. There must be policies to ensure the cleaning and use of cleaning agents on walls, floor, windows, beds, baths, toilets and other medical devices. Proper ventilated and fresh filtered air can eliminate airborne bacterial contamination. Regular check of filters and ventilation systems of general wards, operating theatres and ICUs must be maintained and documented. Infections attributed to water are due to failure of healthcare institutions to meet the standard criteria. Microbiological monitoring methods should be used for water analysis. Infected patients must be given separate baths. Improper food handling may cause food borne infections. The area should be cleaned and the quality of food should meet standard criteria [22].

7.2. Transmission from staff

Infections can be transferred from healthcare staff. It is the duty of healthcare professionals to take role in infection control. Personal hygiene is necessary for everyone so staff should maintain it. Hand decontamination is required with proper hand disinfectants after being in contact with infected patients. Safe injection practices and sterilized equipments should be used. Use of masks, gloves, head covers or a proper uniform is essential for healthcare delivery [22].

7.3. Hospital waste management

Waste from hospitals can act as a potential reservoir for pathogens that needs proper handling. 10–25% of the waste generated by healthcare facility is termed as hazardous. Infectious healthcare waste should be stored in the area with restricted approach. Waste containing high content of heavy metals and waste from surgeries, infected individuals, contaminated with blood and sputum and that of diagnostic laboratories must be disposed off separately. Healthcare staff and cleaners should be informed about hazards of the waste and it’s proper management [22].

8.1. Infection control programs

9.1. Appropriate antimicrobial use

Antibiotics are greatly used to cure illness. Antimicrobial use should justify the proper clinical diagnosis or an infection causing microorganism. The Centers for Disease Control and Prevention (CDC) estimates that each year about 100 million courses of antibiotics are prescribed by office-based physicians, while approximately 50% of those are unnecessary [27]. The selection of antimicrobials should be based upon the patient’s tolerance in addition to the nature of disease and pathogen. The aim of antimicrobial therapy is to use a drug that is selectively active against most likely pathogen and least likely to cause resistance and adverse effects [22]. Antimicrobial prophylaxis should be used when it is appropriate i.e. prior to surgery, to reduce postoperative incidence of surgical site infections. In case of immunocompromised patients, prolonged prophylaxis is used until immune markers are reinstate [28].

9.2. Antibiotic resistance

Antibiotic resistance is responsible for the death of a child every five minutes in South-East Asia region. Drugs that were used to treat deadly diseases are now losing their impact due to emerging drug resistant microorganisms [29]. Self medication with antibiotics, incorrect dosage, prolonged use, lack of standards for healthcare workers and misuse in animal husbandry are the main factors responsible for increase in resistance. This resistance threatens the effective control against bacteriathat causes UTI, pneumonia and bloodstream infections. Highly resistant bacteria such as MRSA or multidrug-resistant Gram-negative bacteria are the cause of high incidence rates of nosocomial infections worldwide [30]. South-East Asian region reports reveal that there a high resistance in E. coli and K. pneumoniae for third generation cephalosporin and more than quarter of S. aureus infections are methicillin resistant [31]. “Immediate action is needed to stop the world from heading towards pre-antibiotic era in which all achievements made in prevention and control of communicable diseases will be reversed”, said Dr Poonam Khetrapal Singh, Regional Director of WHO South-East Asia Region [32].

9.3. Antibiotic control policy

The worldwide pandemic of antibiotic resistance shows that it is driven by overuse and misuse of antibiotics, which is a threat to prevent and cure the diseases. WHO’s global report on antibiotic resistance, preventing the infection from happening by better hygiene, clean water, and vaccination to reduce the need of antibiotics. The development of new diagnostics and other tools is required in healthcare institutes to stay ahead of evolving resistance. Pharmacists should play their role of prescribing the right antibiotic when truly needed and policymakers should foster cooperation and information among all stakeholders [31].