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Infectious Disease Surveillance in Romania: Second Edition

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A special issue of Microorganisms (ISSN 2076-2607). This special issue belongs to the section "Public Health Microbiology".

Deadline for manuscript submissions: closed (20 January 2026) | Viewed by 9609

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Dr. Daniela Piţigoi

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1. Department of Epidemiology, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania
2. National Institute for Infectious Diseases “Prof. Dr. Matei Balș”, 021105 Bucharest, Romania
Interests: vaccine preventable diseases; surveillance; vaccination; infection control; influenza; West Nile
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Special Issue Information

Dear Colleagues,

This Special Issue is a continuation of our 2025 Special Issue “Infectious Disease Surveillance in Romania”.

Communicable diseases continue to pose a challenge to public health systems, both globally and in Romania. Diseases can spread rapidly from one country to another, with new pathogens being identified frequently. Antibiotic resistance, a lack of information, misinformation, vaccine hesitancy, migration, and economic and social crises are the risk factors associated with outbreaks, so it is necessary to implement robust, functional surveillance systems that provide timely information regarding the monitoring of communicable disease trends. This is necessary to identify risk factors and areas for intervention. Epidemiological surveillance systems must be capable of collecting and analyzing data, disseminating information to public health authorities, and regularly assessing the effectiveness of the disseminated data.

This Special Issue aims to present recent findings related to the surveillance and control of communicable diseases in Romania. We welcome both original research and review articles whose scope includes, but is not limited to, the following topics:

The surveillance, epidemiology, clinical and microbial features of communicable diseases in Romania;
The surveillance of vaccine-preventable diseases and vaccinations in special population groups;
The molecular epidemiology of specific infections;
Challenges and advances in the surveillance and control of outbreaks, and in alert management;
The surveillance of influenza, COVID-19 and severe acute respiratory infections;
The surveillance of healthcare-associated infections, antimicrobial resistance and antibiotic consumption;
The technologies and tools used for the surveillance and control of communicable diseases, including vaccination monitoring;

We look forward to receiving your contributions.

Dr. Daniela Piţigoi
Guest Editor

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Keywords

surveillance
vaccine preventable diseases
antimicrobial resistance
health care associated infection
influenza
COVID-19
Romania

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Published Papers (10 papers)

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Research

Jump to: Review

15 pages, 1302 KB

Open AccessArticle

Molecular Characterization of Streptococcus pneumoniae Strains Isolated from Patients with Invasive Infections in a Romanian Hospital

by Endre Csaba Pál, Hunor Váradi, Attila Bitai, Mihaela Oprea, Sorin Dinu, Laura-Ioana Popa, Előd Ernő Nagy and Edit Székely

Microorganisms 2026, 14(2), 418; https://doi.org/10.3390/microorganisms14020418 - 10 Feb 2026

Viewed by 533

Abstract

Invasive pneumococcal disease (IPD) results from the dissemination of Streptococcus pneumoniae to normally sterile anatomical sites such as the bloodstream or cerebrospinal fluid. One of the primary roles of pneumococcal conjugate vaccines (PCVs) used in Romania is to reduce the burden of pneumococcal disease. This single-center retrospective study provides an updated overview of IPD epidemiology in a Romanian tertiary hospital. We analyzed 67 IPD cases identified between 2017 and 2023, of which 45 isolates underwent whole-genome sequencing followed by multilocus sequence typing. Results of genome sequence analysis revealed a diverse population of pneumococci, underlining the importance of continuous genomic surveillance. Expanded-valency pneumococcal conjugate vaccines (PCVs), particularly PCV20, showed markedly improved serotype coverage compared to PCV7 and PCV13, while PCV21 showed serotype coverage comparable to that of PCV13. Antimicrobial susceptibility testing revealed sustained resistance to beta-lactams, particularly among meningitis isolates, underscoring the need for targeted antibiotic stewardship and continuous monitoring of local resistance trends. Overall, these findings highlight the evolving epidemiology of invasive pneumococcal disease in Romania, in the post-PCV era, and the need to adapt vaccination and treatment strategies accordingly. Full article

(This article belongs to the Special Issue Infectious Disease Surveillance in Romania: Second Edition)

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14 pages, 703 KB

Open AccessArticle

Clinical Outcomes and Molecular Epidemiology of Human Metapneumovirus in Romanian Hospitalized Patients

by Ovidiu Vlaicu, Oana Săndulescu, Anca Streinu-Cercel, Anca Cristina Drăgănescu and Victor Daniel Miron

Microorganisms 2026, 14(2), 403; https://doi.org/10.3390/microorganisms14020403 - 8 Feb 2026

Viewed by 510

Abstract

Human metapneumovirus (hMPV) is an important cause of acute respiratory tract infections. This study aimed to describe the clinical characteristics, outcomes, and molecular features of hMPV infection among hospitalized patients in Romania. We performed an analysis of prospectively collected surveillance data from patients hospitalized with influenza-like illness or severe acute respiratory infection and tested by RT-PCR for the presence of respiratory viruses between November 2023 and May 2025. Only cases of hMPV monoinfection were analyzed. Clinical, laboratory, and outcome data were analyzed, and a subset of samples with high viral load underwent genetic sequencing of the hMPV fusion (F) gene. A total of 71 patients met the criteria. Children accounted for 62.0% of cases. The clinical features were nonspecific, dominated by cough (87.3%), fever (80.3%), and nasal congestion (47.9%). Adults were significantly more likely to develop dyspnea and respiratory failure requiring oxygen supplementation (51.9% vs. 6.8%, p < 0.001). The median length of hospital stay was 5 days (interquartile range: 2, 7 days), and dyspnea at admission was the strongest factor associated with prolongation of hospitalization. The rate of intensive care unit admission was 4.2%, and overall outcomes were favorable, with no deaths recorded. Molecular analysis revealed the circulation of different hMPV subclades across consecutive seasons, with A2b1 predominating in 2023–2024 and A2b2 in 2024–2025. hMPV infection in hospitalized patients presents with nonspecific clinical features and shows distinct age-related patterns of severity and complications. Early identification of respiratory involvement, particularly dyspnea at presentation, may support risk stratification and optimized clinical management. Preliminary molecular data indicate dynamic circulation of hMPV subclades, underscoring the value of integrated clinical and molecular surveillance. These findings support the inclusion of hMPV in the differential diagnosis of severe acute respiratory infections and highlight the importance of continued monitoring in the post-pandemic period. Full article

(This article belongs to the Special Issue Infectious Disease Surveillance in Romania: Second Edition)

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15 pages, 1858 KB

Open AccessArticle

Leptospirosis in Central Romania: A 17-Year Single-Center Cohort Study of Hospitalized Adults

by Victoria Birlutiu and Rares-Mircea Birlutiu

Microorganisms 2026, 14(2), 298; https://doi.org/10.3390/microorganisms14020298 - 27 Jan 2026

Viewed by 540

Abstract

Leptospirosis is an important zoonosis that can present as a self-limited influenza-like illness or progress to severe, including life-threatening multiorgan dysfunction. We report the epidemiology, clinical profile, and correlates of severity among adults hospitalized patients with leptospirosis diagnosed in central Romania over a period of 17 years. We conducted a retrospective, single-center cohort study of adults admitted between 1 January 2008 and 1 December 2025 with laboratory-confirmed leptospirosis. Confirmation was based on positive anti-Leptospira IgM serology, with repeat testing when the initial result was equivocal and confirmation with a microscopic agglutination test. We extracted demographic, exposure, clinical, laboratory, treatment, and outcome data from medical records. The modified Faine score was also calculated using admission data. Sixty-four patients were included in this analysis, of which 53 (82.8%) were male patients. Admissions peaked in 2023–2025 (34/64, 53.1%) and in the August–September months. Reported exposures were predominantly peri-domestic (46.9%), followed by rural/animal-related occupations (20.3%) and freshwater contact (17.2%). Severe disease occurred in 26/64 (40.6%), was more frequent in men (p = 0.021), and was more common pre-pandemic than during/after the pandemic (p < 0.001). Severe cases were associated with oliguria/anuria, hematuria, and jaundice, alongside higher urea/creatinine and bilirubin, lower hemoglobin and lymphocyte percentages, and a longer hospitalization period. One in-hospital death occurred (1.6%). Serogroup identification was available for 10 patients (15.6%) (pre-pandemic only). The mean modified Faine score was 27.5 ± 6.0. In this temperate-region cohort study, hospitalized leptospirosis showed a marked male predominance, a late-summer peak, and a substantial burden of severe disease. Early renal and hepatobiliary manifestations with concordant laboratory abnormalities may support timely risk stratification and escalation of care, while expanded molecular diagnostics and systematic typing are needed to clarify temporal trends and guide prevention. Full article

(This article belongs to the Special Issue Infectious Disease Surveillance in Romania: Second Edition)

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16 pages, 387 KB

Open AccessArticle

Experience of a Romanian Lyme Borreliosis Centre in the Multidisciplinary Management of Patients Evaluated for Suspected Lyme Neuroborreliosis

by Violeta Briciu, Angela Monica Ionicǎ, Simona Mureşan, Astrid Binder, Cristina Cismaru, Oana Stan, Blanca Szolga, Cǎtǎlina Hǎpǎianu, Mirela Flonta and Mihaela Lupşe

Microorganisms 2026, 14(2), 264; https://doi.org/10.3390/microorganisms14020264 - 23 Jan 2026

Viewed by 691

Abstract

Lyme neuroborreliosis (LNB) may mimic other neurological diseases, while neurological diseases may be misdiagnosed as LNB. The aims of the study were to contribute to the knowledge regarding the epidemiology and clinical manifestations of LNB, discuss differential diagnosis, and compare characteristics in patients with and without LNB. We present patients evaluated for suspected LNB by the multidisciplinary team of a “Lyme Borreliosis Centre” in a highly endemic area in Romania. A retrospective study was performed between January 2011 and October 2023 on patients referred for suspected LNB based on neurological manifestations and positive serology for Borrelia burgdorferi antibodies using two-tier testing. A lumbar puncture was performed for diagnosis, and the European LNB definition was used for classification. Of three hundred and three LNB suspected patients, five (1.65%) were classified as definite LNB, eighty-three (27.39%) as possible LNB, and in two hundred and fifteen patients (70.95%), LNB was excluded. Comparing the definite/possible to excluded LNB patients, there was no significant difference in neurological symptoms/manifestations. The patients presented fifty-one neurological, twelve rheumatological, and seven psychiatric diagnoses, with significantly more meningitis/encephalitis/myelitis diagnoses in the definite/possible LNB group, and more demyelinating disease and discopathy in the LNB-excluded group. Considering the complex differential diagnoses, access to laboratory diagnostics and multidisciplinary management should be available in centres that evaluate suspected LNB patients. Comparing results with data from the national surveillance system, we conclude that LNB is underdiagnosed/underreported in Romania. Full article

(This article belongs to the Special Issue Infectious Disease Surveillance in Romania: Second Edition)

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19 pages, 298 KB

Open AccessArticle

HPV Vaccination in Romania: Attitudes, Practice, and Knowledge Among Frontline Healthcare Providers

by Maria Moise-Petu, Lacramioara Aurelia Brinduse, Eugenia Claudia Bratu and Florentina Ligia Furtunescu

Microorganisms 2026, 14(1), 205; https://doi.org/10.3390/microorganisms14010205 - 16 Jan 2026

Viewed by 645

Abstract

Recognizing cervical cancer as a major public health concern, Romania was among the first EU countries to introduce human papilloma virus (HPV) vaccination in 2008. Despite multiple strategies implemented over the past 17 years, HPV vaccine coverage remains one of the lowest in the EU, while cervical cancer mortality rates are among the highest. To explore the underlying factors, we conducted a cross-sectional study involving 209 family physicians at the national level. The study assessed their attitudes, practice, knowledge, and training needs related to HPV vaccination. The majority of physicians (90%) reported that they provide HPV vaccination services, and 88.5% considered themselves to have good and very good knowledge about HPV, which they routinely share during consultations with patients. However, respondents noted that both physician and public attitudes toward HPV vaccination are only moderately positive, which limits vaccine uptake and the success of prevention efforts. Parental hesitation was the main barrier, mentioned by 81.8% of respondents. The majority (71.3%) of doctors indicated that they were able to adequately respond to patients’ questions, but 81.4% of respondents expressed the view that additional training is needed for healthcare professionals on HPV infection and vaccination. These findings highlight the need for coordinated efforts to increase demand and trust in HPV vaccination. Recommended strategies include targeted professional training, public information campaigns, and the development of strong cross-sector partnerships to support vaccination efforts. Full article

(This article belongs to the Special Issue Infectious Disease Surveillance in Romania: Second Edition)

21 pages, 864 KB

Open AccessArticle

PCR-Based Versus Conventional Stool Testing in Hospitalized Patients with Diarrhea: Diagnostic Yield, Clinical Impact, and Stewardship Implications

by Alina Boeriu, Adina Andone, Daniela Dobru, Cristina Nicoleta Ciurea, Victoria Ancuta Nyulas, Danusia Onișor, Brindusa Tilea, Lavinia Andrada Matei, Reka-Bernadett Imreh-Ferenci and Crina Fofiu

Microorganisms 2025, 13(12), 2785; https://doi.org/10.3390/microorganisms13122785 - 7 Dec 2025

Viewed by 1811

Abstract

Accurate and timely identification of enteric pathogens is crucial for guiding treatment in hospitalized patients with acute diarrhea. Conventional stool testing often lacks sensitivity, whereas multiplex PCR diagnostics offer rapid, comprehensive pathogen detection. This retrospective multicenter study included 267 adult inpatients with acute diarrhea from two hospitals. Patients underwent either traditional stool diagnostics (n = 146) or multiplex PCR testing combined with stool culture (n = 121). Clinical data, diagnostic yields, antibiotic use, and clinical outcomes were analyzed. The multiplex PCR group demonstrated a significantly higher diagnostic yield than traditional testing (77.7% vs. 41.1%, p < 0.001), detecting more mixed infections (34.7%) and a broader range of pathogens, including Campylobacter, viruses, and parasites. PCR positivity correlated independently with bloody diarrhea (OR 16.5; 95% CI: 1.81–150.26) and dehydration (OR 7.05; 95% CI: 1.40–35.45). PCR testing reduced inappropriate antibiotic use (OR 0.30; p < 0.001), shortened antibiotic duration post-result (median 5 vs. 7 days; p < 0.0001), and increased antibiotic adjustments (42.1% vs. 27.4%; p = 0.011) and discontinuation (12.4% vs. 3.7%; p = 0.033). The PCR group had more ICU admissions (20.7% vs. 7.1%, p = 0.001) and longer hospital stays (median 10 vs. 6 days, p < 0.0001), reflecting more severe illness. Liver cirrhosis, comorbidity burden, and systemic inflammation predicted worse outcomes. Multiplex PCR enhances pathogen detection and promotes antibiotic stewardship in hospitalized patients with diarrhea. Rapid results support earlier, targeted clinical decisions, particularly in patients with complex comorbidities or severe presentations. Full article

(This article belongs to the Special Issue Infectious Disease Surveillance in Romania: Second Edition)

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16 pages, 1262 KB

Open AccessArticle

Seven Years of Salmonella: Changing Resistance and Clinical Insights

by Cristina Mihaela Sima, Aida Corina Bădescu, Georgiana Buruiană, Alexandru Duhaniuc, Luminița Smaranda Iancu, Eduard-Vasile Năstase and Olivia Simona Dorneanu

Microorganisms 2025, 13(12), 2655; https://doi.org/10.3390/microorganisms13122655 - 22 Nov 2025

Viewed by 1059

Abstract

Non-typhoidal Salmonella (NTS) represents a growing public health concern worldwide due to its increasing antimicrobial resistance and substantial disease burden, yet data from Romania remain limited. We conducted the first regional 7-year retrospective study of NTS-associated diarrhea among hospitalized patients, focusing on resistance trends and clinical factors associated with disease severity. This study included all laboratory-confirmed Salmonella infections admitted for acute diarrheal disease to the “Sfânta Parascheva” Clinical Hospital of Infectious Diseases, Iași (January 2018–December 2024). Patient data were extracted from electronic medical records and analyzed using SPSS (v31.0), with statistical significance set at p < 0.05. Among the isolates obtained from the 698 included patients, most belonged to serogroup D (63.6%), followed by B (21.8%) and C (14.0%). Overall resistance rates were 12.3% for ampicillin, 3.6% for trimethoprim–sulfamethoxazole and 29.9% for ciprofloxacin, with a significant yearly increase observed only for ciprofloxacin (OR = 1.21, p < 0.001). Cardiovascular comorbidities were independently associated with prolonged hospitalization (>5 days) (OR = 2.25, p = 0.007). Invasive infections occurred in 14 patients (2%). Given the high ciprofloxacin resistance and the additional impact of comorbidities on disease severity, there is a need for ongoing surveillance and targeted management strategies. Full article

(This article belongs to the Special Issue Infectious Disease Surveillance in Romania: Second Edition)

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13 pages, 639 KB

Open AccessArticle

Hepatitis E Virus Infection in a Hospital from Southern Romania—New Data About a Threat to Public Health

by Cristina Popescu, Alexandra Cireșă, Gabriel Adrian Popescu, Carmen Cristina Vasile, Leontina Mirela Bănică and Dragoș Florea

Microorganisms 2025, 13(10), 2290; https://doi.org/10.3390/microorganisms13102290 - 1 Oct 2025

Viewed by 1178

Abstract

This study analyses all cases of acute hepatitis E diagnosed in a southern Romanian hospital from 2019 to 2023. Patients with positive anti-HEV IgM antibodies were included in three groups: group A1—96 patients with probable HEV infection and ALT levels over 2.5-fold the upper limit of normal (ULN); group A2—44 patients with probable HEV infection and ALT levels under 2.5-fold ULN; group B—43 patients with probable HEV coinfection with another hepatotropic virus. Between 2019 and 2023, 642 patients were diagnosed with acute viral hepatitis. Positive anti-HEV IgM antibodies were detected in 183 (28.5%) cases, HEV being the second most common cause of acute viral hepatitis. Patients from group A were older than those from group B (47.26 ± 15.13 years vs. 35.95 ± 14.83 years, p < 0.01). Patients from group A were less likely to present clinical features compared to those from group B: digestive symptoms (73.8% vs. 97.2%, p < 0.01), jaundice (38.9% vs. 88.4%, p < 0.01), hepatomegaly (64.1% vs. 88.6%, p = 0.02). Patients from group A, compared to patients from group B, had lower levels of ALT (18.2 ± 29.9 ULN vs. 83.7 ± 56.2 ULN, p < 0.01) and total bilirubin (3.08 ± 5.2 mg/dL vs. 7.82 ± 5.25 mg/dL, p < 0.01) at admission. Patients from group A had higher levels of anti-HEV IgM antibodies (4.3 ± 3.22 vs. 2.55 ± 1.34, p < 0.01) than those from group B. Nearly all patients had no history of travel; therefore, autochthonous origin of HEV is involved in a large majority of cases. Currently, hepatitis E virus is not an uncommon aetiology of acute hepatitis in Romania, more often in adults and elderly patients. The epidemiological and clinical features of HEV infections plead for a zoonotic transmission in most cases. The significant number of cases of hepatitis E diagnosed in a single centre in Bucharest justifies the need to include early testing for HEV in patients with acute hepatitis. Full article

(This article belongs to the Special Issue Infectious Disease Surveillance in Romania: Second Edition)

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Review

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27 pages, 432 KB

Open AccessReview

Evolution of Antimicrobial Resistance in Acinetobacter baumannii and Pseudomonas aeruginosa in Romania: A Narrative Review of Published Data (2001–2024)

by Elena Roxana Buzilă, Olivia Simona Dorneanu, Luminița Smaranda Iancu, Felicia Trofin, Alexandru Duhaniuc, Costin Damian and Cătălina Luncă

Microorganisms 2026, 14(2), 429; https://doi.org/10.3390/microorganisms14020429 - 11 Feb 2026

Viewed by 682

Abstract

Antimicrobial resistance constitutes a major global public health challenge, with Romania among the European countries affected. Acinetobacter baumannii and Pseudomonas aeruginosa was designated by the World Health Organization (WHO) as priority pathogens, are frequently implicated in healthcare-associated infections (HAIs), including pneumonia, surgical site infections, urinary tract infections, and bacteremia. We have narratively synthesized surveillance studies published in different regions of Romania, encompassing date whit the period 2001–2024. A total of 13 studies reporting data on P. aeruginosa (2003–2024) and 15 studies on A. baumannii (2001–2024) were included. The strains were isolated from various pathological products, including urine, sputum, tracheobronchial aspirate, blood, bronchoalveolar lavage, pus, peritoneal fluid, and cerebrospinal fluid, from hospitalized patients in different clinical departments. This review evaluated long-term trends in antimicrobial resistance profiles of A. baumannii and P. aeruginosa strains circulating in various regions of Romania. The findings revealed both temporal variability in resistance rates within comparable intervals and differences across distinct time periods. These long-term trends underscore the need for sustained national surveillance systems, harmonized reporting practices, and reinforced antimicrobial stewardship programs. Full article

(This article belongs to the Special Issue Infectious Disease Surveillance in Romania: Second Edition)

22 pages, 582 KB

Open AccessReview

Vector-Borne Infections in Romania: From Surveillance to Prediction

by Anca-Elena Duduveche

Microorganisms 2026, 14(1), 61; https://doi.org/10.3390/microorganisms14010061 - 26 Dec 2025

Viewed by 802

Abstract

Vector-borne infections are a growing public health concern in Romania, influenced by ecological diversity, climate change, and socioeconomic factors. West Nile virus, tick-borne encephalitis, and Lyme borreliosis represent the most significant threats, with additional risks posed by emerging pathogens, such as leishmaniasis, and the potential reintroduction of malaria. While surveillance systems exist for human cases and, to a lesser extent, vectors, these remain fragmented, underfunded, and limited in their integration across human, veterinary, and environmental health domains. By highlighting both gaps and opportunities, this review provides a forward-looking perspective on strengthening Romania’s capacity to anticipate and manage vector-borne disease threats. Transitioning from reactive surveillance to proactive, prediction-driven strategies will be critical to safeguarding public health in the context of accelerating environmental change. Full article

(This article belongs to the Special Issue Infectious Disease Surveillance in Romania: Second Edition)

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