Healthcare-associated infections (HAIs) constitute a major global public health concern worldwide with a high attributable morbidity and mortality. ¹

They lead to a heavy economic burden on health systems by extending the length of patient’s hospital stay in healthcare settings, increasing medical care costs and prescribing supplementary antibiotics, thus increasing the risk of antimicrobial resistance problem. ²

This concern represents a real health threat, especially in the developing countries with a higher morbidity and mortality compared to developed countries. The risk of contracting a HAI during hospital stay is multiplied by 2 to 20 times in developing countries with a prevalence that can exceed 25% in some countries. ³

This problem is still largely underestimated in these countries because of the lack of surveillance data and epidemiological studies. ⁴

There are limited data on HAIs available in Tunisia. According to the latest published results of the national nosocomial infection prevalence survey conducted in 2005 “NosoTun-2005”, the prevalence of HAIs was of 13.2%. ⁵

Conducting regular cross-sectional point prevalence surveys to have punctual and rapid baseline information about HAIs is recommended and constitutes a good alternative to overcome the problem of unavailable continuous prospective surveillance system in hospital settings. ⁶

Before instauration of a prevention strategy program at a healthcare institution we need to assess the magnitude of the HAIs problem and to identify the high-risk population to establish priorities of infection prevention and control.

This study aimed to estimate the prevalence of HAI among adult patients at the Charles Nicolle Hospital (CNH) of Tunis and to identify the main associated factors as well as to estimate the frequency of antibiotic use.

The control of the infectious risk is considered as an indicator of quality of care. HAIs represent one of the serious healthcare-associated adverse events at health care structures that threaten patient safety. ⁹

The principal findings of our point prevalence survey were that approximatively one patient out of eight had at least one active HAI, and one among three patients was under at least one antibiotic agent on the survey day. The most frequently reported site infections were urinary tract infections followed by surgical site infections and pneumonia.

Comparing to other studies conducted in Tunisian hospitals, a similar prevalence was found at Farhat Hachad Hospital in 2012 with a prevalence of HAIs of 12.5%. ¹⁰ Lower prevalences of 10.9% and 9.1% was reported in two university hospitals in Sfax in 2017 and 2019, respectively. ^{11 , 12}

Another study carried out in Sahloul Hospital based on data collected from prevalence surveys conducted between 2012 and 2020 revealed a total prevalence of 10.8%. ¹³

The higher prevalence found in our study can be explained by the relatively higher number of wards specialized in interventional procedures (2 large general surgery departments, 2 adult intensive care units, a gastroenterology department), which may increase the infectious risk.

Our results were close to those estimated in other studies carried out in low- and intermediate-income countries with an estimated overall HAI prevalence of 15.5%, according to a meta-analysis conducted in 2011. ¹ It reached 28% in some Saharan African countries. ^{14 , 15} Our prevalence was considerably higher compared to developed countries, in particular European countries with a global prevalence of 7.5%. ¹⁶

Theses discrepancies may be due to the inexistence of a monitoring system and control of these infections in health structures, especially in developing countries. Such systems ensure the application and the respect of hygiene rules by all health care staff, and the availability of all the necessary materials for hand hygiene. All these conditions are not always available in hospitals in developing countries, which may explain the higher prevalence of HAI in these countries compared to other developed countries.

In our study, independent risk factors identified as associated with increased HAI risk were having hypertension, consuming alcohol, being infected at admission, having at least one invasive device during last 7 days prior to the survey date and undergoing surgery 30 days prior to the study date.

Indeed, hypertension is a predisposing factor to atherosclerosis, which in turn leads to a stimulation of the immune system with its two cellular and humoral components. ¹⁷

On the other hand, alcohol causes a secondary immune deficiency by a molecular mechanism, which increases the risk of infections in general and HAIs in particular. ^{18 , 19}

Like our fundings, several studies have shown that a history of surgery during the 30 days prior to admission and recent exposure to invasive medical devices are risk factors for HAIs. ^{12 , 13 , 20 , 21}

In general, a special attention should be given to immunocompromised and infected patients who constitute a population with a very high risk of contracting this type of infections.

The most important avoidable risk factor identified in our study was the exposure to invasive devices.

The risk of contracting device-associated HAIs is known as preventable. ²² It depends essentially on the degree of respect of hygiene rules, the quality of their daily care and their insertion time before remove. Thus, their indication, their number and their insertion time must be limited as possible.

Implementing evidence-based practices using bundles in infection prevention can improve patient safety and reduce HAIs related to invasive devices. ^{22 , 23}

The most frequently identified sites of infection in our study, were urinary tract infections, pneumonia and superficial surgical site infections. This result joins that found in several other studies in Europe, ^{24 – 26} Asia and Africa. ⁴ Similarly, a study conducted in Sfax in the two university hospitals, Hedi Chaker and Habib Bourguiba, Tunisia, in 2017 ¹¹ found similar results.

Escherchia coli and Pseudomonas aeroginosa were the most frequently isolated germs with a frequency of 27.8% respectively for each germ, and in third place Acinetobacter baumannii. These Gram-negative bacteria are the most frequently isolated type according to the literature. In fact, this result is in line with a systematic review study conducted in 2019 that included European, Asian and African studies, which found the same results. ⁴ These two types of germs have also been identified in other Tunisian surveys. ^{10 , 11 , 27}

Gram-negative bacteria have a great capacity of acquisition of genes coding for antibiotic resistance, which may explain their frequent incrimination in HAIs. ²⁸

Otherwise, health care workers represent a main component in the transmission process of these infections. The main axis of prevention that can be targeted is improving hand hygiene compliance among health care workers which have been demonstrated being significantly effective in reducing the nosocomial infection risk. ²⁹

Providing regular training and reminders using posters at the workplace settings can be very useful. Raising the degree of awareness about the importance of the problem and the necessity of their implication as a principal actor on prevention strategy, is needed to reduce the occurrence of these infections. Continuous availability of alcohol-based hand rubs at point of care is also a very important component to motivate hand hygiene practice. ³⁰

The prevalence of antibiotic use, in our study, was alarming. Almost one patient out of three was under antibiotic therapy on the day of the survey and third generation Cephalospoins (Claforan) were the most frequently prescribed antibiotics. This prevalence was comparable to that estimated in some developed countries (overall prevalence of 35%, ranging from 21% in some countries to 55%). ^{24 , 31} More than half of patients receiving antibiotics were under two or more agents. Rational use of antibiotic combinations and reduction of unnecessary antibiotic prescribing is needed. Creating an antibiotic stewardship program is very important to limit the development of antibiotic resistance in health care facilities.

In the other hand, our survey enabled us to estimate in a simple and inexpensive way the frequency of HAIs and antibiotic use among adult wards at the Chrales Nicolle Hospital.

Point prevalence survey is considered as a useful, rapid, and cost-effective method to quantify the magnitude of HAI problem and target interventions priorities, particularly in hospitals with limited resources. ^{32 , 33}

It was an opportunity to raise awareness and remind health care workers about the importance of the nosocomial infectious risk and to increase their motivation and their adherence to the prevention programs.

Incidence surveys are the gold standard tool used in HAIs surveillance, but they require much more time, resources, and costs. Repeated point prevalence surveys are a good alternative method for measuring HAIs trends over time and to assess the impact of interventions and control programs and actions. ³⁴

Controlling HAIs is a long-term process that requires the implication of multidisciplinary staff (clinicians, microbiologists, epidemiologists, hygienists, pharmacists, and administrative agents), and needs a good coordination of their interventions with a clear definition of each one tasks and responsibilities. But it supposes a minimum of local possibilities, in relation to the premises, materials, organization of care and a certain degree of agreement about behaviors and practices.

The prevalence rates of HAIs and antimicrobial use in adult wards at CNH were relatively high. Hospital infection prevention and control measures need to be strengthened to reduce the burden of HAI at the institutional level. Infection control priorities must essentially target urinary tract infections, surgical site infections and pneumonia.

An infection prevention and control committee, as well as the development of an antibiotic stewardship program with continuous monitoring using repeated prevalence surveys, must be implemented to limit the frequency of these infections effectively.

While further research is necessary by estimating the incidence of these infections prospectively over time to understand the principal risk factors and evaluating their real economic impact by estimating the direct cost of HAIs.