Nosocomial infections especially in NICUs are a major cause of long-term morbidity and mortality. So, there is a need for good and active surveillance system to ensure the compliance of the implemented infection control strategies with the national infection control guidelines and to evaluate the applied antibiotic policy.

It is impossible to make the environment surrounding neonates to be completely sterile. As there are many factors that make neonates at risk to be infected including healthcare staff caring for them, their feeding, the use of many equipment and medical devices for their care. In addition to their immature immune system which makes them to be more susceptible for infections.

In our country, many studies reported that the incidence of nosocomial infections (NI) among neonates were 21.4%¹² and 38.5%⁵ which are close to our results (25.3%) while a higher percent was reported by El-Fiky, et al.¹³. In another study done by Basiri, et al.¹⁴, the incidence of nosocomial infection was 5.7% while low incidence of nosocomial infections was reported in developed countries ranged from 3.5 to 11.1% in the USA and from 1.6% to 13.2% in Europe^15-19.In our study, we found that most of the admitted neonates with gestational age in the range of 28-36 weeks and low birth weight. The majority of neonates under investigation were males. In addition, most of neonates showing nosocomial infections had a length of stay in the NICU that exceeded 7 days. These findings were supported by several studies^20-23 that indicate the increase in the risk of nosocomial infection with the decrease in the gestational age and birth weight and the increase in the duration of the hospital stay. As Mugauri and Mashumba²⁴ reported that neonates who had > 7 days stay, premature and low birth weight developed the signs of neonatal sepsis and klebseilla spp. were the most common. They found that the poor adhesion to the national infection control guidelines was the main cause of sepsis.

In this study, we found that infection control practices were not applied as recommended by the national infection control guidelines. Poor infection control practices facilitate the transfer of pathogenic organisms from the hospital environment to patients, health care team to patients and among patients occupying the same room. Other factors that facilitate the spread of organisms are the state of immune system which may be affected by illness or the use of drugs. In addition, antibiotic use which leads to the selection of resistant strains. It was found that 65% of nursing staff that is in contact with infected persons, their white coats, shirts, ties of doctors carried pathogenic flora^25,26. There are many factors affect the transmission of pathogens such as infectious dose, route of administration and host susceptibility.

Many studies showed that the intervention in the applied disinfection strategies improves the effectiveness of housekeeping and cleaning practices. Datta, et al.²⁷ reported that there was a reduction in methicillin resistant staphylococci (MRSA) acquisition by 62% and vancomycin resistant enterococci (VRE) by 22% for patients admitted to rooms which were occupied by patients colonized by these organisms. Denton, et al.²⁸ showed that the replacement of detergent with 1000 ppm of hypochlorite decreased environmental contamination with Acinetobacter baummanii and ended outbreaks caused by these organisms.

Pessoa-Silva, et al.²⁹ demonstrated that hands contamination with pathogenic strains and normal flora occurs at high rates especially in neonatal care and gloves do not fully protect workers. In addition, Pittet, et al.³⁰ found that the amount of pathogens increased by time in ungloved hands which indicate the importance of decontaminating hands. Also, it was found that using alcohol gel before the contact with patient, decreased infection rates during 34 months.

After the daily and weekly follow-up to housekeeping routine in NICU in the second period, a decrease in the number of culture positive environmental samples was observed and CONS were the most common (43.7%).Hayden, et al.³¹ found that housekeeping education, monitoring of the implemented infection control guidelines and improved cleaning decreased the contamination of the hospital environment from 10% to 3-4%. Also, applying good hand washing practices decreased hand contamination rate from 55% to 10 – 11% and decreased the transfer of VRE.

Grabsch, et al.³² substituted the used detergent (quasi experimental) by hypochlorite (1000 ppm) in the routine disinfection of all rooms. Cleaning supervisors were shared to ensure the complete compliance of housekeeping protocol to the implemented protocol. A formal training program for cleaning staff was assessed to increase awareness by the infection control guidelines. They modified the health care workers personal protective equipment (HCW PPE) protocols for managing spread of infection as followed: wearing disposable protective sleeveless plastic aprons, application of routine alcohol-based hand rub (ABHR) instead of using gloves (except when performing surgical procedures). Their results showed significant decrease in new VRE colonization by 25% in high-risk patients, and VRE bacteremia across the entire hospital by 83.1%.

In our study, the most common infection sites were blood stream followed by respiratory tract which may be attributed to the exposure of neonates to invasive medical procedures  such as umbilical catheterization, endotracheal intubation or Intravenous cannula which agreed with many studies^33-35. The difference in results between different studies can be attributed to the difference in places at which studies were performed. The basis at which nosocomial infection was diagnosed is the incidence rate of blood culture positive results due to the inability to obtain adequate volume of blood samples³⁶.

In developing countries, many studies showed that klebseilla spp. were the most common pathogens while in developed countries, it was found that Gram positive cocci especially coagulase negative Staphylococci (CONS) were the most common pathogen isolated from blood cultures^{16, 37-39}. In the present study, Gram positive cocci and Gram negative rods (GNR) were isolated at the same rate (57/114, 50 % each) (before applying the new policy) but E. coli was the most prevalent pathogen (35.9%) but Gram positive cocci and Gram negative rods were found to represent 57.5% and 42.4% of the isolated strains, respectively in the second period. Many studies showed that Gram positive cocci were isolated at a higher incidence than Gram negative rods^{40, 41} while in a study done by Nambiar and Singh³⁵, they reported that GNRs were isolated at a rate of 42.7% and Gram positive cocci were isolated at a rate of 33.5%.

In a study performed by Stoll, et al.¹⁶, at national institute of child health (NICHD), they  found that 70% of the isolated organisms belonged to the Gram positive organisms (CONS, S. aureus, Enterococcus spp., streptococci group B) while GNR represented 20% of isolates that differs from our results. In a study done by Bokulich, et al.⁴² streptococci and staphylococci were found to be the most common pathogens. They found that the intensive cleaning of the NCIU reduced their prevalence while enterobacteriaceae members were found to be isolated at low rates. In addition, these organisms were the main causes of the infectious outbreaks occurred in the period of 2011-2012.

In our study, Mortality rate before the implementation of the new antibiotic policy was 14.1% while after the implementation of the new policy, training staff on how to apply the infection control protocols and hand washing practices, the mortality rate decreased to 9.5%. Many different researches were carried out in the developing countries showed that the mortality rates among neonates admitted to NICU ranged from 11.9 to 14.7% which is close to our results and higher than that reported in the developed countries (ranged from 6.1 to 7.1%)^{19, 43-45}. The decrease in mortality rate in our study may be attributed to the implementation of the new antibiotic policy and the recommended infection control guidelines.

In a study done by Wu, et al.⁴⁶, the use of a culture guided antibiotic stewardship program by trained staff resulted in a decrease in the misuse of antimicrobials and their costs in Japan, USA, Taiwan. As a result, antibiotic resistance decreased among Gram positive and Gram-negative rods and the predominant strains were E. coli and Klebseilla pneumoniae. Also, they reported an increase in the resistance of Gram-positive bacteria to cefazoline and Gram-negative rods to ampicillin/sulbactam. In addition, the duration of stay decreased to less than 2 weeks and the yearly mortality rate was reduced from 1.3% in 2011 to 1.1% in 2012 and 1% in 2013.

Our results showed an improvement in the susceptibility of the isolated Gram positive to many antibiotics such as ciprofloxacin, cefotaxime, cefepime, Amoxicillin/clavulanate, ampicillin, amikacin and gentamicin while an increase in the resistance of Gram positive to imipenem, linezolid, vancomycin, ampicillin/sulbactam was observed which may be attributed to the disappearance of some organisms such as S. aureus and the emergence of new strains such as S. pneumoniae. For Gram negative isolates, significant increase in the susceptibility of the isolates to the tested antibiotics was shown except in case of imipenem and ampicillin which may be due to the emergence of resistant isolates of K. pneumoniae and the decrease in incidence of the isolated E. coli.

In our study, we observed that despite of knowing the terminal disinfection protocol after the discharge of patients, this protocol was not practiced resulting in the infection of the new admitted neonates by the same bacteria. Also, we found that all staff did not receive formal or informal training on the infection control policy. Poor compliance of the implemented infection control protocols with national infection control guidelines and the absence of clear visitor’s policy. All these factors facilitate the transfer of resistant pathogens among the admitted neonates and from the healthcare and the hospital environment to neonates. As a result, failure of the antimicrobial therapy, increase in the mortality rate and the need to the use of multiple antibiotics were great challenges facing the health care team. So, there was a need to apply strict infection control practices to gain great benefits from the applied antibiotic policy. The same conclusion was obtained by Jinka, et al.⁴⁷ who showed that the controlled antibiotic use is accompanied by decrease in infections caused by multi-drug resistant pathogens in NICUs. Furthermore, the success of antibiotic policy may be affected by poor infection control practices. So, application of strict infection control practices is essential to increase benefits gained by an antibiotic policy.

Considering the change of the distribution of microbial community by time, further regular studies should be performed to ensure these results and to help in the choice of the proper antimicrobials for the empiric treatment of hospital acquired infections in neonates.

As a result of this study, many benefits were gained which were:

• Increasing the rate of the participation of infection control health workers, physicians and nurses in the different training workshops on the infection control measures.
• Increasing the awarenes of the application of infection control measures and the role of microbiological monitoring in hospitals.
• Educating the medical staff about the antibiotic policy concepts and their importance in controlling the spread of antimicrobial resistance.
• Discussing the inappropriate prescription of antibiotics and its effects in the presence of doctors.
• Directing doctors to prescribe unrestricted or less expensive antibiotics instead of the restricted or the more expensive ones if both were recommended by the culture sensitivity results.