Table 1 Summary of the characteristics of the included studies that have assessed the knowledge of IPC among HCWs (n = 25), 2006–2021

Abeje et al. [28], Ethiopia

Evaluate hepatitis B vaccination knowledge among HCWs

Multi-centre

374 HCWs (nurses, health officers, medical doctors, dentists, and laboratory technologists)

Survey: cross-sectional questionnaire; [(Williamson critical appraisal of qualitative evidence, LOW risk of bias)]

HCWs who scored above the mean (mean knowledge score of respondents was 7.6) were classified knowledgeable using a questionnaire tool with a total score ranged from 0 to 10. Only 52% of the respondents were knowledgeable about hepatitis B infection and 62% of HCWs were knowledgeable about hepatitis B vaccine

Albano et al. [16], Italy

Assess knowledge towards influenza A/H1N1 and the vaccination among HCWs

Multi-centre

600 HCWs (physicians, nurses and others)

Survey: cross-sectional questionnaire; [(Hoy critical appraisal checklist, LOW risk of bias)]

Only 36.1% knew the main modes of transmission, and that HCWs are a risk category. Level of knowledge was significantly higher in HCWs having received information through scientific journals (OR = 1.63; 95% CI 1.12–2.38)

Majority acquired knowledge from public-media (63.5%), followed by health-care professionals (47.1%), and the internet (45%)

Alsahafi et al. [43], Saudi Arabia

Assess knowledge of HCWs to MERS coronavirus

Multi-centre

1216 (687 nurses, 267 physicians, and 262 other HCWs)

Survey: questionnaire; [(Hoy critical appraisal checklist, LOW risk of bias)]

Majority of HCWs correctly identified patient risk factors (i.e., 88% of the physicians, 69.5% of the nurses and 62.5% of the other HCWs; p < 0.001). A low percentage of HCWs was aware that asymptomatic MERS-CoV was described (i.e., 47.6% of the physicians, 30.4% of the nurses and 29.9% of the other HCWs; p < 0.001)

The most common sources of MERS-CoV information were the Ministry of Health (MOH) memo (74.3%) and MOH web page (72.4%), with smaller proportions reporting use of the MOH Helpline (43.8%) and medical journals (48.2%)

Majority of the HCWs (≥ 72.3%) indicated that that they are in need for educational courses and training about the MERS-CoV, Ebola and other emerging infectious diseases

Only 22.8% reported having received training about dealing with infectious disease outbreaks, 37.1% reported training in infection control policies and procedures, 54.4% reported training in hand hygiene and 45.6% reported training in N95 mask wearing techniques

Amoran et al. [53], Nigeria

Assesses level of knowledge with standard precautions by HCWs

Single centre

421 HCWs (52 doctors, 78 nurses, 54 laboratory scientists, 53 pharmacists, 57 community health workers, 74 hospital orderlies, and 53 other professions)

Survey: cross-sectional questionnaire; [(Williamson critical appraisal of qualitative evidence, LOW risk of bias)]

Majority (77.9%) of HCWs were able to correctly describe universal precaution and IPC. Some of the HCWs could not recognize vaccination (19.2%), PEP (19.2%), and surveillance for emerging diseases (28.0%) as standard precaution for IPC. Only 2.1% of HCWs were aware of National Injection Safety Policy and 1.9% were aware of Policy on Sharps Disposal

Only 8.1% of HCWs had attended any workshop or training in IPC in the last 2 years and almost all of the HCWs admitted training needs on IPC

Arora et al. [29], India

Assess knowledge of HCWs about the NSSIs

Single centre

190 HCWs (50 doctors, 100 nurses, 15 technicians, and 25 housekeeping staff)

Survey: cross-sectional questionnaire; [(Hoy critical appraisal checklist, LOW risk of bias)]

Majority (94.7%) were aware about standard precautions. Only 50.2% HCWs gave correct answers regarding disease transmission through NSSIs

Ashraf et al. [30], United States

Assess knowledge of 2002 CDC hand hygiene guidelines

Multi-centre

1143 HCWs (386 nursing assistants, 375 nurses, and 382 other healthcare professionals)

Survey: questionnaire; [(Hoy critical appraisal checklist, MODERATE risk of bias)]

Most HCWs (83.6%) reported familiarity with the CDC guidelines. Nurses were more likely to answer most of the questions correctly, compared with nursing assistants and other professionals (p values < 0.05)

About (20.8%) of HCWs did not receive any hand hygiene training or orientation in the prior year or were not sure whether they had received training

Assefa et al. [17], Ethiopia

Evaluate knowledge of HCWs about hand hygiene practices, utilization of PPE, and PEP, healthcare waste management practices, and instrument disinfection practice

Multi-centre

171 HCWs (about 83 were nurses)

Survey: questionnaire; [(Williamson critical appraisal of qualitative evidence, LOW risk of bias)]

About 70.8% of HCWs had adequate knowledge (i.e., a HCW score on IPC knowledge was equal or above the mean)

About 19.3% of HCWs didn’t take any training on IPC and universal precautions

Having IPC guideline (AOR = 3.65, 95% CI 1.26, 10.54), taking IPC training (AOR = 2.2, 95% CI 1.01, 4.75), having 5 years or more work experience (AOR = 1.52: 95% CI 1.13, 4.51), and working in maternity unit (AOR = 1.67; 95% CI 1.38–5.23) were positively associated with adequate knowledge of IPC

Chuc et al. [31], Vietnam

Assess and compare HCWs knowledge and self-reported practices of IPC in a rural and an urban hospital

Multi-centre

339 HCWs (nurses, midwives, physicians and cleaners)

Survey: cross-sectional questionnaire; [(Hoy critical appraisal checklist, LOW risk of bias)]

Majority of HCWs had good (i.e., a total score of 7.5 to < 11.25) or adequate (i.e., a total score ≥ 11.25) knowledge using a questionnaire tool with a total score ranged from 0 to 15

Cleaners had lower knowledge than both physicians and nurses [OR (95% CI ): 0.13 (0.04–0.51), p = 0.001 and 0.12 (0.03–0.41), p < 0.001] compared to physicians and nurses/midwives, respectively

Desta et al. [54], Ethiopia

Examine the knowledge and practice of HCWs on IPC and its associated factors among health professionals

Single centre

150 HCWs (21 Physician, 83 nurses, 18 midwives, 3 health officers, 13 lab technicians, 12 others)

Survey: cross-sectional questionnaire; [(Hoy critical appraisal checklist, LOW risk of bias)]

Majority (84.7%) of the HCWs in the hospitals had adequate knowledge on IPC

HCWs with experience of above 10 years was four times more likely knowledgeable on IPC than those had work experience of fewer than 5 years (AOR = 4.03, 95% CI = [1.229–5.68])

HCWs with an educational level of master or above and were three times (AOR = 3.034, 95% CI = [1.856–4.756]) and bachelor were two times (AOR = 2.15, 95% CI = [3.245–8.789]) more likely knowledgeable than diplomas

Furthermore, HCWs who haven’t taken IPC training were 75% less likely knowledgeable (AOR = 0.25, 95% CI = [1.689–3.95]) about IPC than those had taken training in IPC

Douville et al. [52], United States

Determine knowledge of children's hospital HCWs toward mandatory influenza vaccination

Single centre

585 HCWs (physicians, nurses, and all other hospital employees)

Survey: questionnaire; [(Hoy critical appraisal checklist, LOW risk of bias)]

Comparing those who favored a mandate with those who opposed one, knowledge about CDC recommendations was high for both groups (i.e., difference on knowledge of two variables: 89.3% vs 90.1%, p = 0.82; and 83.6% vs 80.2%, p = 0.46; respectively) and there were no significant differences in knowledge about the dangers of influenza for patients (i.e., difference on knowledge of two variables: 59.2% vs 61.3%, p = 0.8; and 70.5% vs 61.7%, p = 0.12; respectively)

Geberemariyam et al. [18], Ethiopia

Assess knowledge of HCWs towards IPC

Multi-centre

648 HCWs (physicians, nurses, midwives, anesthetists, laboratory technicians, laboratory technologists, pharmacists, pharmacy technicians, and radiographers)

Survey: cross-sectional questionnaire; [(Hoy critical appraisal checklist, LOW risk of bias)]

HCWs who scored above the mean were classified knowledgeable using a questionnaire tool with a total score ranged from 0 to 10

Only 53.7% (95% CI 49.8–57.4) of the HCWs were assessed as knowledgeable (if score was above the mean). HCWs were more likely to have IPC knowledge if they worked longer 10 years or more (AOR = 3.41; 95% CI 1.22–9.55), worked in facilities with IPC committees (AOR = 1.78; 95% CI 1.01–3.13), had IPC guidelines available (AOR = 3.34; 95% CI 1.65–6.76) and had training (AOR = 5.02, 95% CI :1.45–8.59)

Iliyasu et al. [8], Nigeria

Explore the knowledge of IPC among HCWs in a tertiary referral center

Single centre

200 HCWs (152 nurses and 48 doctors)

Survey: cross-sectional questionnaire; [(Hoy critical appraisal checklist, LOW risk of bias)]

Most HCWs (87.9%) correctly identified hand hygiene as the most effective method to prevent HAIs, with nurses having better knowledge (91%, p = 0.001). Only (44.4%), (61.6%), and (42.4%) of the HCWs were aware of the risks of infection following exposure to HIV, HBV and HCV-infected blood, respectively

Labeau et al. [41], 22 European countries

Determine European ICU nurses’ knowledge of guidelines for preventing CVCs-related infection from the CDC

Multi-centre

3405 European ICU nurses

Multi-country survey (October 2006–March 2007). Using a multiple-choice test, knowledge of the ten recommendations for CVCs-related IPC was evaluated; [(Hoy critical appraisal checklist, MODERATE risk of bias)]

The mean score was 4.44 on ten questions. Only 56% knew that CVCs should be replaced on indication only. About 26% recognized that both polyurethane and gauze dressings are recommended. Only 14% checked 2% aqueous chlorhexidine as the recommended disinfection solution. Only 26% knew sets should be replaced every 96 h when administering neither lipid emulsions nor blood products. Experienced nurses performed significantly better than less experienced nurses (p < 0.001 for < 5 years vs. > 5 years ICU experience). Nurses from larger ICUs scored significantly lower than nurses from smaller units (p < 0.001 for < 8 vs. > 8 beds and for < 15 vs. > 15 beds, respectively)

Loulergue et al. [51], France

Evaluate HCWs knowledge regarding occupational vaccinations (HBV, varicella and influenza)

Single centre

580 HCWs (physicians, nurses, nurses’ assistants)

Survey: cross-sectional questionnaire; [(Hoy critical appraisal checklist, LOW risk of bias)]

Knowledge about the occupational vaccinations of HCWs was low (i.e., 25% of the HCWs were able to list correctly the three mandatory vaccines). Pediatric staff was more aware of influenza and pertussis immunizations (p < 0.05). Physicians and nurses have better knowledge about influenza vaccine recommendations than the others (60.4% and 32.7%, respectively, p < 0.05). About 45% of HCWs could not cite any recommended vaccinations and 32% cited a mandatory vaccine as recommended

Influenza vaccination was associated with knowledge of vaccine recommendations [OR = 1.75, 95% CI 1.13–2.57] and contact with patients [OR = 3.05, 95% CI 1.50–5.91]

Michel-Kabamba et al. [42], Democratic Republic of the Congo

HCWs knowledge on COVID-19-related clinical manifestations and patient care approach was assessed using WHO’s “Exposure Risk Assessment in the Context of COVID-19” questionnaire

Multi-centre

613 HCWs (27.2% were medical doctors and 72.8% were other categories of HCWs)

Survey: cross-sectional questionnaire; [(Hoy critical appraisal checklist, MODERATE risk of bias)]

Over 80% of HCWs had sufficient knowledge on: COVID19 symptoms (89.2% of doctors vs. 80.7% of other HCWs; p < 0.05) and patient care approach (89.8% of doctors vs. 83.8% of other HCWs; p < 0.05)

Only 41.9% of HCWs had attended a lecture, meeting, or discussion about COVID-19

Most of the HCWs mostly used the news media and social media as primary sources of information on COVID-19, whereas the government’s and WHO’s websites were used less

COVID-19 knowledge was positively associated with the COVID-19-related IPC practices (AOR: 3.45 ± 2.40; 95% CI 1.88–13.49; p < 0.05)

Mody et al. [27], United States

Assess knowledge of recommended urinary catheter care practices among nursing home HCWs

Multi-centre

356 HCWs (127 nurses and 229 nurse aides)

Survey: questionnaire; [(Hoy critical appraisal checklist, LOW risk of bias)]

More than 90% of HCWs were aware of measures such as cleaning around the catheter daily, glove use, and hand hygiene with catheter manipulation. HCWs were less aware of research‐proven recommendations of not disconnecting the catheter from its bag (59% nurses vs. 30% aides, p < 0.001), not routinely irrigating the catheter (48% nurses vs. 8% aides, p < 0.001), and hand hygiene after casual contact (60% nurses vs. 69% aides, p = 0.07). HCWs were also unaware of recommendations regarding alcohol-based hand rub (27% nurses and 32% aides with correct responses, p = 0.38)

With respect to urinary catheter care, about 52% and 24% of HCWs reported that they learned from didactic formal [in-services, lectures, and nursing school and nurse aides' courses] and informal [prior experience, nurse supervisors, co-workers, and facility policies] methods, respectively; and 24% gained their knowledge both informally and formally

Regarding hand hygiene, 51% reported that they learned from didactic formal methods, 15% for informal methods, and 34% gained their knowledge by both informal and formal methods

Ogoina et al. [34], Nigeria

Examine knowledge of some components of standard precautions among HCWs in two tertiary hospitals

Multi-centre

290 HCWs (111 doctors, 147 nurses and 32 laboratory scientists)

Survey: cross-sectional questionnaire; [(Hoy critical appraisal checklist, LOW risk of bias)]

Overall median knowledge scores toward standard precautions were above 90%. Majority of the HCWs had poor knowledge of injection safety (50% of participants were ignorant of the WHO’s recommendation that sharps/needles should never be recapped, bent or broken)

Knowledge of medical laboratory scientists was significantly lower than that of the principal nursing officer/chief nursing officer (85% vs 95%, p = 0.027) and the knowledge of the staff nurse/senior nursing officer (90%) were also significantly lower than those of the principal nursing officer/chief nursing officer (p = 0.049)

About 51.4% of HCWs never had training on IPC and HCWs who had prior IPC training had significantly higher median knowledge percentage scores than those who did not have prior training [median: 95% vs 90%, IQR: 75–95; p = 0.002]

Parmeggiani et al. [3], Italy

Assess HCWs knowledge on IPC in the EDs

Multi-centre

307 HCWs (nurses, physicians and other healthcare professionals)

Survey: cross-sectional questionnaire; [(Hoy critical appraisal checklist, LOW risk of bias)]

Majority (87.9%) were aware that HCWs can acquire HCV and HIV from a patient, but less than one-third knew that HCWs can transmit these infections to a patient. Majority identified as proper HAIs control measures the use of gloves, mask, and protective eye wear (94.1%) and hands hygiene measures after removing gloves (91.5%). Overall, 86.3% were aware of both preventive measures and this knowledge was significantly higher in nurses (OR = 2.34, 95% CI 1.09–5.01, p = 0.029)

Knowledge of proper HAIs IPC measures was significantly higher in HCWs who received information about HAIs from educational courses and scientific journals (OR = 3.54; 95% CI 1.47–8.5). Furthermore, HCWs who have received information about HAIs from educational courses and scientific journals (OR = 3.54; 95% CI 1.22–10.24), and who did not need additional information about HAIs (OR = 0.06; 95% CI 0.01–0.55) were more likely to know the risk for a HCW of acquiring both HCV and HIV from a patient

Sources of information about HAIs were: educational courses (71%), and scientific journals (48.2%); however, 85.3% of HCWs claimed to need to update what they already knew

Paudyal et al. [44], Nepal

Assess HCWs knowledge on IPC in the acute care hospitals

Multi-centre

324 HCWs (158 doctors and 166 nurses)

Survey: questionnaire; [(Hoy critical appraisal checklist, LOW risk of bias)]

Although mean knowledge scores were high, only 16% answered the entire knowledge section correctly. Doctors had significantly higher scores on (OR = 4.39, 95% CI 1.67–11.45, p = 0.003), as did older staff and those who had worked abroad OR = 3.06, 95% CI 1.60–5.85, p < 0.001). Most HCWs knew about methods of transmission (92%), hand hygiene practice (99%), HAIs prevention by complying with protocols (93%), and reducing cross-infection by using gloves, masks, and aprons (97%)

Only 24% of HCWs had received training in IPC

Raab et al. [45], Guinea

Assesses the knowledge and practices of HCWs towards Ebola virus amongst in public healthcare facilities

Multi-centre

102 HCWs (31 technical assistants, 30 nurses, 15 physicians, 14 midwives, and 12 others)

Survey: questionnaire; [(Hoy critical appraisal checklist, LOW risk of bias)]

Overall knowledge on viral hemorrhagic fever was good among 99% of all interviewed HCWs

Only 40.2% thought they would accept an approved vaccine for themselves and 37.3% would accept this for their parents for viral hemorrhagic fevers

Significantly more HCWs in rural than urban healthcare facilities of the prefecture lacked IPC training (42.9% vs. 21.7%; p = 0.029)

Russell et al. [21], United States

Explore factors for compliance with IPC practices at 2 healthcare agencies

Multi-centre

359 nurses

Survey: questionnaire; [(Hoy critical appraisal checklist, LOW risk of bias)]

Nurses demonstrated correct knowledge (mean = 0.85, SD = 0.09), however, knowledge of IPC practices was not associated with compliance

Majority of nurses reported having received IPC training in the previous year, with more than 39.3% reporting having received IPC training in the previous 6 months. However, less than 18.1% of nurses had formal IPC certification

Shi et al. [46], China

Assess knowledge of HCWs in 2 Chinese mental health centers during the COVID-19 outbreak

Multi-centre

311 HCWs (141 psychiatrists and 170 psychiatric nurses)

Survey: questionnaire; [(Hoy critical appraisal checklist, LOW risk of bias)]

Majority (79.10%) reported having extensive knowledge of COVID-19 (82.97% for physicians vs 75.88% for nurses, p = 0.125), and 78.78% expressed confidence in their ability to protect themselves and their patients (84.39% for physicians vs 74.12% for nurses, p = 0.027)

About 64.63% of HCWs had finished a COVID-19 training program. Apart from the training program organized by their hospitals, various media (including the internet, television, and newspapers) were also major sources of knowledge. Moreover, significantly more physicians (38.30%) obtained their relevant knowledge from medical journals compared with nurses (7.06%)

Tavolacci et al. [47], France

Compare knowledge of hand hygiene between HCWs

Multi-centre

1811 HCWs (physicians, nurses, nursing assistants and others)

A questionnaire; [(Hoy critical appraisal checklist, LOW risk of bias)]

Physicians had better knowledge about hand hygiene than other HCWs. Knowledge of antiseptic efficacy of hand hygiene was 68.5% in senior physicians, 37.5% in consultants, and 52.9% in registrars and residents

With regards to alcohol hand rub, sources of information were: colleagues (43.3%), IPC practitioner (33.3%), head nurses (27.6%), poster (14.4%), hospital epidemiologist (9.1%), articles in hospital's newspaper (5.7%), intranet (4%), IPC committee (2.6%)

Temesgen et al. [48], Ethiopia

Assess knowledge of TB IPC among HCWs in 4 healthcare facilities

Multi-centre

313 HCWs (59 physicians, 175 nurses, and 79 other healthcare professionals)

Survey: questionnaire; [(Hoy critical appraisal checklist, LOW risk of bias)]

Majority [74.4%, 95% CI (69.6, 79.3)] were found to have good knowledge (≥ 60% correct answers). Only 34.2% of the HCWs knew that respirators can provide protection from inhaling mycobacterium tuberculosis bacilli and only 46% correctly identified that use of a fan (ventilator) minimizes the risk of TB infection

Only 18.8% of the HCWs were trained on TB IPC. Of these, 45% were trained in the past year while 55% were trained in the past two or more years

Training was the strongest determinant of TB IPC knowledge, AOR 3.386 and 95% CI (1.377, 8.330)

Tenna et al. [49], Ethiopia

Evaluate HCW knowledge about hand hygiene and TB IPC measures at 2 university hospitals

Multi-centre

261 HCWs (133 physicians and 128 nurses)

Survey: cross-sectional questionnaire; [(Hoy critical appraisal checklist, LOW risk of bias)]

Hand hygiene knowledge was fair (60%). TB IPC knowledge was excellent (more than 90% correct)

Only 56% of HCWs correctly believed that gloves do not provide complete protection against acquiring or transmitting infection (71% of physicians vs. 41% of nurses, p < 0.05). Only 59% knew that an alcohol-based hand sanitizer was as effective as soap and water when the hands were not visibly dirty (51% of physicians vs. 68% of nurses, p < 0.05)

Only 50% of HCWs reported receiving hand hygiene training and only 30% thought their supervisors stressed the importance of hand hygiene

Trigg et al. [50], England

Evaluate HCWs knowledge regarding MRSA IPC precautions

Single centre

411 HCWs (47 physicians, 270 nurses, and 94 other health professionals)

Survey: cross-sectional questionnaire on the current guidelines for MRSA infection (Joint Working Party, 2006); [(Hoy critical appraisal checklist, LOW risk of bias)]

Staff showed high levels of knowledge on the IPC precautions required when caring for patients with MRSA (i.e., 84% HCWs knowledge was above 5), but some were confused about the level of isolation required for these patients (i.e., 35% of staff indicated isolation for some MRSA patients)

Less than 46% of all HCWs had received any formal teaching. Highest percentage of HCWs who received education were doctors and unregistered nurses (51% and 53% respectively). Hotel services staff received the least, at 21%; 57% of HCWs felt that they had not received adequate education about MRSA with only doctors satisfied with the amount of education received