Infections In Poland Research Articles

The Effects of Climate and Bioclimate on COVID-19 Cases in Poland

The correlations between air temperatures, relative and absolute humidity, wind, cloudiness, precipitation and number of influenza cases have been extensively studied in the past. Because, initially, COVID-19 cases were similar to influenza cases, researchers were prompted to look for similar relationships. The aim of the study is to identify the effects of changes in air temperature on the number of COVID-19 infections in Poland. The hypothesis under consideration concerns an increase in the number of COVID-19 cases as temperature decreases. The spatial heterogeneity of the relationship under study during the first year and a half of the COVID-19 pandemic in Polish counties is thus revealed.

Public awareness of contagious diseases

Introduction: Restrictions against the COVID-19 pandemic have resulted in a decrease in other contagious diseases. However, their prevention and treatment are still a topical issue.
 Purpose: To present the public awareness on infectious diseases taking into account the knowledge of people with medical education.
 Material and method: The study was conducted by means of the author's questionnaire. 158 questionnaires were collected and analysed.
 Results: Men and women of different age took part in the survey. Half of the respondents had medical education. The analysis showed that as many as 89.2% of the respondents were aware of the pathogenic factor of influenza, which is the virus. Only a small percentage of respondents had information regarding the number of influenza infections in Poland (10.8%) and worldwide (21.5%). Medics were aware of this in 10.0% and 28.8% respectively. Influenza was admitted by 81.0% of the respondents, while for other infectious disease (except COVID-19) the result was 75.3%. The respondents indicated as the most common route of transmission of infectious diseases the droplet route (66.5%), while fever was the typical symptom (81.0%). Washing hands turned out to be the most important prophylactic behaviour of respondents (50.6%) and especially of students (93.7%).
 Conclusions: Awareness of infectious diseases among Poles is not at the highest level. Those with medical education have slightly higher knowledge, but it is necessary to introduce educational programmes and update knowledge.

The risk of blood-borne infections in Poland - opportunities and threats to public health, nationwide qualitative research.

The article presents the diagnosis of the problem of blood-borne infections in Poland from perspectives of experts' opinions at the voivodship level. The evaluation became the basis for subsequent analysis, aimed at creating assumptions for the proposed strategies to prevent blood-borne infections in Poland. Diagnosis was based on the expertise of practitioners in epidemiology and service providers. Analysis covered assessment of service safety, examples, recommended practices, forms and scope of education. Also covered is information for the general public from different aspects: points of view of recipients and service providers, legislation, system organization, and finances. The SWOT method was used in analysis. The opportunities and threats concerning the risk of blood-borne diseases for the service sector are presented, as well as data gathered from 42 representative experts from across Poland. Databases on health indicators, covered by the reporting obligation of all diagnosed cases, are a crucial element of the surveillance system in public health (e.g. sentinel). Additional information on health care management (risk management) is not a common and routine approach. The study fills a gap in knowledge about risk management in the medical and non-medical services sector. The information also enriches education programmes (e.g. http://www.hcv.pzh.gov.pl/). Currently, the evidence-based approaches in medicine and in public health are standard. Experts emphasize that the opportunities for the prevention of infection risk are linked to technological advances and innovations, while threats are seen in both financial and organizational constraints, and the non-normalized, dynamically developing service market.

Level of Knowledge of Medical Staff on the Basis of the Survey in Terms of Risk Management, Associated with Clostridioides difficile Infections.

Infections caused by the toxigenic strains of Clostridioides difficile in the hospital environment pose a serious public health problem. The progressive increase in hospital infections in Poland indicates that risk management is a tool that is not used in an effective way and significantly differs from the goals set by the Leading Authorities, the Ministry of Health and its subordinate units. Systematic education of medical personnel constitutes the basic element of rational risk management aimed at reducing the number of infections as it allows for the transfer of knowledge, development of appropriate organizational procedures, and improves internal communication. This paper presents the results of a survey conducted in hospital facilities throughout Poland. The study dealt with what medical personnel know about channels of transmission and prevention of Clostridioides difficile infections in the hospital setting, professional training and risk management in terms of reducing the number of infections. The survey reveals that Clostridioides difficile continues to be a serious problem in the inpatient care system. Procedures and management strategies implemented by hospitals in order to limit the spread of the pathogen are predominantly focused on short-term action, which does not lead to a real improvement in terms of hospitalized patients’ safety. The infection risk management system was assessed at a fairly low level. The obtained research results confirmed the research hypotheses that had been formulated.

High prevalence of anti-HEV antibodies among patients with immunosuppression and hepatic disorders in eastern Poland.

IntroductionThe incidence of hepatitis E virus (HEV) infections in Poland is largely unknown. This study aimed to describe seroprevalence of markers of HEV infection among patients with immunodeficiency of diverse etiology and patients with advanced chronic liver diseases.Material and methodsFour hundred fifty patients were enrolled; among them, 180 persons were solid organ transplant recipients, 90 patients were HIV-infected and 180 persons had confirmed liver cirrhosis of different etiology. Serum anti-HEV-IgG, IgM antibodies and HEV-antigen were detected by ELISA (Wantai, China).ResultsIn the group of transplant recipients, serum anti-HEV-IgG antibodies were detected in 40.6%, IgM in 1.1% and HEV-Ag in 2.8% of subjects. In the HIV-infected population 37.7% had anti-HEV-IgG, 1.1% had anti-HEV-IgM and none had HEV-Ag. Among patients with advanced chronic liver diseases the highest prevalence of anti-HEV-IgG was recorded in alcohol-related liver cirrhosis (52.1%) (p = 0.049). In the population of all liver cirrhotics anti-HEV-IgG seroprevalence was 48.3%, anti-HEV-IgM seroprevalence was 5.0% and HEV-Ag seroprevalence was 1.7%. Older age and male gender were significant risk factors associated with increased anti-HEV-IgG prevalence, p = 0.0004 and p = 0.02, respectively.ConclusionsIn this large cohort a high seroprevalence of anti-HEV-IgG was detected in comparison to other European countries, with the highest rates in patients with alcoholic liver disease and in transplant recipients.

First Case of Staphylococci Carrying Linezolid Resistance Genes from Laryngological Infections in Poland.

Linezolid is currently used to treat infections caused by multidrug-resistant Gram-positive cocci. Both linezolid-resistant S. aureus (LRSA) and coagulase-negative staphylococci (CoNS) strains have been collected worldwide. Two isolates carrying linezolid resistance genes were recovered from laryngological patients and characterized by determining their antimicrobial resistance patterns and using molecular methods such as spa typing, MLST, SCCmec typing, detection of virulence genes and ica operon expression, and analysis of antimicrobial resistance determinants. Both isolates were multidrug resistant, including resistance to methicillin. The S. aureus strain was identified as ST-398/t4474/SCCmec IVe, harboring adhesin, hemolysin genes, and the ica operon. The S. haemolyticus strain was identified as ST-42/mecA-positive and harbored hemolysin genes. Linezolid resistance in S. aureus strain was associated with the mutations in the ribosomal proteins L3 and L4, and in S. haemolyticus, resistance was associated with the presence of cfr gene. Moreover, S. aureus strain harbored optrA and poxtA genes. We identified the first case of staphylococci carrying linezolid resistance genes from patients with chronic sinusitis in Poland. Since both S. aureus and CoNS are the most common etiological factors in laryngological infections, monitoring of such infections combined with surveillance and infection prevention programs is important to decrease the number of linezolid-resistant staphylococcal strains.

Spatio-temporal analysis of the development of the COVID-19 epidemic (pandemic) in Poland: First phase of development

The purpose of this study is to present a description of the course of the COVID-19 epidemic in Poland in the space-time dimension in the period from March 15th to August 8th 2020. The result of the conducted research is a presentation of the regional differentiation of the course of the epidemic in Poland, the comparison of the intensity of SARS-CoV-2 infections in particular voivodeships, the determination of the degree of similarity in the course of the pandemic development process in individual regions (voivodeships) of the country, and also the indication of the factors which could be taken into account when attempting to explain the interregional differences in the course of the epidemic. The conducted research shows, among other things, that: (1) in terms of time, the development of the epidemic was generally monotonic, however the increase in new infections was rather cyclical, (2) in the spatial dimension, the development of the epidemic was rather random, although the greatest number of infections was characteristic of the most populated regions of the country, (3) the level of infections in Poland was mainly positively influenced by: population density, working in industry, people beyond retirement, age as well as a poorly developed material base of inpatient care.

Congenital cytomegalovirus infections in Poland – a national hospital register-based study

Congenital cytomegalovirus (cCMV) infections are common worldwide. CCMV infected newborns are mostly asymptomatic at birth. However, cCMV remains the major infectious cause of congenital abnormalities in the developing foetus and newborns. The aim of the study was to provide recent data on cCMV in Poland. Aretrospective, population-based study was conducted using data from hospital discharge records of patients hospitalized from 2009-2018. CCMV incidence rates were estimated on the basis of data taken from a Polish hospital morbidity study, carried out by the National Institute of Public Health. The study group consisted of 1,916 hospitalized patients with the first-time diagnosis of cCMV. Among them, 52% were patients up to 30 days of age. The median age was 28 days. The average annual incidence of cCMV was 48 per 100,000 live births (95% CI 23.5-73.4). A significantly higher cCMV incidence rate was observed in patients from more urban than rural regions of Poland (55 per 100,000 vs 39 per 100,000; P<0.001). In the study period, 9 hospital deaths (0.5 % of all patients) were reported. The coexistence of nervous system diseases was observed in 26% of cases and hearing loss in 6% of cases. The significantly more cCMV cases were observed in patients from more urban than rural regions of Poland may suggest the presence of territorial factors related to the cCMV incidence in Poland. The relatively high percentage of newborns with hearing loss or neurologic diseases may require activities aimed at reducing the cCMV incidence. The epidemiological data presented may be useful for comparisons with other geographical regions.

Occurrence of Marek's Disease in Poland on the Basis of Diagnostic Examination in 2015-2018.

IntroductionMarek’s disease (MD) is a tumourous disease caused by Marek’s disease virus (MDV) and most commonly described in poultry. The aim of the study was to determine the occurrence of Marek’s disease virus infections in Poland and analyse clinical cases in the years 2015–2018.Material and MethodsThe birds for diagnostic examination originated from 71 poultry flocks of various types of production. Birds were subjected to anatomopathological examination post mortem, during which liver and spleen sections and other pathologically changed internal organs were taken. These sections were homogenised with generally accepted methods, then total DNA was isolated and amplified with a real-time PCR. A pair of primers complementary to the MDV genome region encoding the meq gene were used.ResultsMDV infection was found predominantly in broiler chicken flocks (69.01%), and also in layer breeder (9.85%) and commercial layer flocks (7.04% each).ConclusionThe results of research conducted in the years 2015–2018 clearly indicate that the problem of MDV infections is still current.

Strengths and Weaknesses in the Risk Management of Blood-Borne Infections: Qualitative Research in Public Health.

This article presents the research from the first phase of our study on blood-borne risk management, wherein we solicited epidemiologists’ and healthcare practitioners’ expert opinions on a blood-borne infection risk assessment in Poland. Forty-two experts were recommended by epidemiology consultants and recruited from all districts in Poland. We used the SWOT (Strengths, Weaknesses, Opportunities, Threats) method in the evaluation. Experts’ opinions showed that there is room for improvement in the prevention of blood-borne infections. Commonly reported weaknesses in the risk assessment included gaps in knowledge and inappropriate procedures, which are largely caused by financial constraints and practitioners’ lack of awareness of developments in their trade. Strengths included legal regulations for medical services and procedures, surveillance, and increasing awareness on the part of medical staff. When paired with the existing statistical data, these results provide a comprehensive view of the problem of blood-borne infections in Poland. The analysis supported the development of a strategy proposal to prevent blood-borne infections and enhance existing risk assessment procedures.

Occurrence of various pathogenic and opportunistic fungi in skin diseases of domestic animals: a retrospective study

BackgroundFungal infection of animals or humans are common all over the world. Some of microorganisms like fungi, exist on the skin and can be transmitted onto other individuals, other animal species or even humans and cause skin infections. Moreover, they can be the causative agents of severe generalized infections especially in immunocompromised individuals. The study aimed to evaluate the most frequent etiological agents of skin diseases and to compare the prevalence of animal fungal infections in Poland, and to discuss the possibility of transmission to humans in Poland.ResultsThe obtained results are culture based. The fungi most frequently isolated from group of animals with skin lesions were Malassezia pachydermatis (29.14%), and Candida yeasts (27.07%), and dermatophytes (23.5%), including Microsporum canis as majority of them (59.25%), and Trichophyton genus (40.7%), most of them T. mentagrophytes, while Malassezia pachydermatis represented (80%) of isolates in animals with otitis externa. In over 19% of positive fungal cultures obtained from external ear canals Candida yeasts, mainly C. albicans, were identified.ConclusionsDermatomycoses in companion animals are caused by both, mycelial fungi and yeasts. Most frequently isolated were Malassezia pachydermatis and Candida spp. Dermatophytes (Trichophyton, Microsporum), were also cultured, but the total number of these isolates seems to decrease. We have not found Cryptococcus neoformans in tested clinical samples.

Growing consumption of antibiotics and epidemiology of Clostridioides difficile infections in Poland: A need to develop new solutions.

Clostridioides (formerly Clostridium) difficile infections (CDIs) are becoming more common and more serious. C. difficile is the etiologic agent of antibiotic-associated diarrhea, pseudomembranous enterocolitis, and toxic megacolon while CDIs recur in 7.9% of patients. About 42.9 CDI cases/10,000 patient-days are diagnosed each day in Europe, whereas in Poland 5.6 CDI cases/10,000 patient-days are reported; however, the median for European countries is 2.9 CDI cases/10,000 patient-days. Epidemiology of CDIs has changed in recent years and risk of developing the disease has doubled in the past decade that is largely determined by use of antibiotics. Studies show that rate of antibiotic consumption in the non-hospital sector in Poland is much higher than the European average (27 vs. 21.8 DDD/1,000 patient-days), and this value has increased in recent years. Antibiotic consumption has also increased in the hospital sector, especially in the intensive care units - 1,520 DDD/1,000 patient-days (ranging from 620 to 3,960 DDD/1,000 patient-days) - and was significantly higher than in Germany 1,305 (ranging from 463 to 2,216 DDD/1,000 patient-days) or in Sweden 1,147 (ranging from 605 to 2,134 DDD/1,000 patient-days). The recent rise in CDI incidence has prompted a search for alternative treatments. Great hope is placed in probiotics, bacteriocins, monoclonal antibodies, bacteriophages, and developing new vaccines.

First report on echinocandin resistant Polish Candida isolates.

Candida spp. are ranked as one of the four major causative agents of fungal infections. The number of infections caused by Candida species resistant to fluconazole, which is applied as the first line drug in candidiasis treatment, increases every year. In such cases the application of echinocandin is necessary. Echinocandin susceptibility testing has become a routine laboratory practice in many countries due to the increasing frequency of clinical failures during treatment with these drugs. We performed anidulafungin, micafungin and caspofungin susceptibility testing according to the microdilution broth method on 240 Candida isolates collected in Polish hospitals. We identified 12 isolates resistant to all echinocandins within 240 examined isolates. Moreover, 6 of the examined samples were identified as rare Candida species and among them we observed very high echinocandin MIC values. Our research proves that in Poland there is a problem of echinocandin resistance. Moreover, we identified two species of Candida which are rare causative agents of human infections, and there was no reported incidence of such infections in Poland until now.

Activity of dalbavancin against gram-positive cocci isolated from skin and soft tissue infections in Poland

A total of 368 Gram-positive cocci from ABSSI were included in the study. S. aureus and S. pyogenes were susceptible to dalbavancin with MIC50 0.016 mg/L and MIC90 0.032 mg/L for MSSA and MIC50 0.032 mg/L and MIC90 0.047 mg/L for MRSA; MICs for S. pyogenes were ≤0.002–0.008 mg/L; for E. faecalis and E. faecium, ranging 0.016–0.12 mg/L and 0.012–≥32 mg/L, respectively; MICs for VRE were 0.032–0.125 mg/L.

FlaA-SVR Based Genetic Diversity of Multiresistant Campylobacter jejuni Isolated From Chickens and Humans.

Campylobacter jejuni is one of the most common causes of human foodborne bacterial infections worldwide. The objective of this study was to assess the molecular diversity, using flaA sequencing, of 602 C. jejuni isolated from chicken food chain, i.e., chicken feces (n = 151), chicken carcasses (n = 150), chicken meat (n = 150), and from humans (n = 151) and to determine antimicrobial multiresistant profiles of the isolates as well as to analyze the relationship of the isolate genotypes with their antimicrobial resistance profiles and source of isolation. Multidrug resistant patterns were identified in 110 (18.3%) C. jejuni isolates recovered from all sources and most isolates were resistant to ciprofloxacin (CIP), nalidixic acid (NAL), streptomycin (STR), and tetracycline (TET) (92; 15.3%) or ciprofloxacin, streptomycin, and tetracycline (13; 2.2%). Only a few isolates were multiresistant to ciprofloxacin, nalidixic acid, tetracycline, and erythromycin (3; 0.5%) or ciprofloxacin, nalidixic acid, streptomycin, tetracycline, and erythromycin (2; 0.3%). A total of 79 flaA-SVR subtypes were identified, including 40 (50.6%) unique to the isolates’ origins, with the most common sequence types 16, 54, 36, 34, and 287 which covered 56 (9.3%), 50 (8.3%), 48 (8.0%), 35 (5.8%), and 32 (5.3%) of C. jejuni isolates, respectively. It was found that 13 isolates had the novel flaA-SVR subtypes which were not present in the pubMLST database. These isolates were recovered from chicken feces (6 isolates), carcasses (2 isolates), meat (one isolate) and from humans (4 isolates). Multiresistant C. jejuni were classified into 26 different sequence subtypes. Among the most numerous multidrug resistant profile CIP+NAL+STR+TET 21 different flaA-SVR subtypes, with total of 92 isolates, were identified. Most of them were classified to 287 (18; 19.6% isolates), 100 (13; 14.1%), 34 (9; 9.8%), 208 (8; 8.7%), and 781 (8; 8.7%) molecular variants. Isolates resistant to CIP, STR and TET (13 isolates) were mainly from chicken feces (12 isolates) and classified into 5 flaA-SVR sequence types, with the most common 36 (8 isolates). The obtained results show a broad molecular diversity of multiresistant C. jejuni isolates and suggest chickens as a possible source of human Campylobacter infections in Poland.

Current epidemiology and practice patterns in prevention and treatment of PD-related infections in Poland.

Peritoneal dialysis (PD) related infections are associated with technique failure and mortality. The aim of this multicentre study was to examine epidemiology, treatment and outcomes of PD-related infections in Poland as well as practice patterns for prevention of these complications in the context of current ISPD recommendations. A survey on PD practices in relation to infectious complications was conducted in 11 large Polish PD centres. Epidemiology of peritonitis and exit-site infections (ESI) was examined in all patients treated in these units over a 2year period. The study included data on 559 PD patients with 62.4% on CAPD. Practice patterns for prevention of infectious complications are presented. The rate of peritonitis was 0.29 episodes per year at risk, with Gram positive microorganisms responsible for more than 50% of infections and 85.8% effectively treated. Diagnosis and treatment followed ISPD guidelines however most units did not provide an anti-fungal prophylaxis. Although neither of the centres reported routine topical mupirocin on catheter exit-site, the rate of ESI was low (0.1 episodes per year at risk), with Staphylococcus aureus as most common pathogen and full recovery in 78.3% of cases. The study shows rewarding outcomes in prevention and treatment of PD-associated infections, mainly due to a thorough compliance with the current ISPD guidelines, although some deviations from the recommendations in terms of practice patterns have been observed. More studies are needed in large numbers of patients to differentiate the importance of specific recommendations and further support the guidelines.

Foodborne infections and intoxications in Poland in 2017

The purpose of this study is to assess the epidemiological situation of food poisonings and infections in Poland in 2017. The evaluation was based on the analysis of information sent to Department of Epidemiology NIPH-NIH through ROE (pol. Rejestr Ognisk Epidemicznych)- (an electronic system created for uploading, transfer and analysis of data acquired during the outbreak investigations). Additional sources for the analysis were NIPH-NIH annual bulletins (Czarkowski MP et al. “Infectious diseases and poisonings in Poland”, 2011-2017. Warsaw, NIPH-NIH and GIS). In 2016 a total number of 926 foodborne infections and intoxications outbreaks were reported in which 27 702 persons were exposed and 7 416. A total number of 2 502 of patients were hospitalized. The most frequent etiological agent of outbreaks was hepatitis A virus (HAV) (27.1%). The most frequent cause of infection for all outbreaks cases was Salmonella sp. – 37.2%, especially serotype Enteritidis (32.2%). Among other agents rotaviruses caused 9.3% of outbreaks and noroviruses 14.5%. In 12.2% of outbreaks no etiological agent was found. The most frequent place of an outbreak was private household- 560 outbreaks (60.4%), and after that- hospital- 155 outbreaks (16.7%). In 86.8% of outbreaks no vehicle was found and in remaining the most frequent vehicle were eggs and egg products- 5.6% % of all outbreaks. Increasing yearly trend of Salmonella Enteritidis outbreaks, and high proportion of eggs and egg products as vehicles in those outbreaks point towards necessity of microbiological surveillance enchantment in relation to abovementioned products. Dynamic increase in HAV outbreaks is a good example of how a pathogen with high epidemic potential could spread in susceptible population.

Hepatitis C in Poland in 2017

The aim of this article was to analyze the epidemiological situation of HCV in Poland in 2017, based on data collected as part of epidemiological surveillance. The analysis was carried out based on: 1) individual data collected as part of epidemiological interviews with persons diagnosed with HCV infection in 2017, 2) diagnosis rate from bulletins “Infectious diseases and poisonings in Poland” for the years 2011-2017 and 3) data about deaths due to hepatitis C from the Demographic Surveys and Labour Market Department of the Central Statistical Office. In 2017, the diagnosis rate of HCV infection stayed on high level: 10.44 per 100,000 (4010 cases were reported). Stabilization of hepatitis C epidemiological situation was observed in the following issues: 1) diagnosis rate reported in men and women remained at a similar level (10.55 vs. 10.33 per 100,000); 2) diagnosis rate still showed variation depending on the voivodship (from 4.09 to 18.48 per 100,000) and the location of residence (urban/rural, 12.7 vs. 7.0 per 100,000); 3) the percentage of hospitalization accompanying the new cases of HCV infection has shown downward trend (36% in 2017); 4) the decreasing hepatitis C mortality trend was continued (175 cases of death in 2017); 5) the most common possible transmission route were still medical procedures. In 2017, the outbreak of HCV infection in the Lubelskie was registered. (8 patients, 291 exposed persons, with whom computer tomography with a contrast from multi-dose packaging was conducted, using an automatic injection device). Epidemiological situation of hepatitis C since 2015 is stable. The role of medical care in the transmission of HCV infections in Poland is worrying.

Hemorrhagic fever with renal syndrome (HFRS) in Poland

Hemorrhagic fever with renal syndrome (HFRS) is an acute viral zoonosis occurring due to the hantavirus infection. On the territory it constitutes the only case of viral hemorrhagic fever. The infections occurring in Poland are mainly caused by the Puumala and Dobrava serotypes. The pathogenetic influence of other Hanta serotypes such as Boginia, Nova and Seewis on humans is still unknown. The endemic territory of the occurrence of the hantavirus infections in Poland is the Podkarpacie region. The morbidity is not high and ranges between 0.02 and 0.14 in every 100 000 but professional literature suggests that the data concerning the territory of Poland is underestimated. So far hantavirus infections have not been reported in other areas of Poland yet the presence of the virus may be excluded. In view of literature and the significant occurrence of Hanta antibodies in patients included in the risk group, it may be claimed that the diseases caused by Hanta virus constitute a significant factor influencing the medical status of the group in focus all over the country.

Foodborne infections and intoxications in Poland in 2016

The purpose of this study is to assess the epidemiological situation of food poisonings and infections in Poland in 2016. The evaluation was based on the analysis of information sent to Department of Epidemiology NIPH-NIH through ROE (Pol. Rejestr Ognisk Epidemicznych)- (an electronic system created for uploading, transfer and analysis of data acquired during the outbreak investigations). Additional sources for the analysis were NIPH-NIH annual bulletins (Czarkowski MP et al. “Infectious diseases and poisonings in Poland”, 2010-2016. Warsaw, NIPH-NIH and GIS). In 2016 a total number of 680 foodborne infections and intoxications outbreaks were reported in which 22 908 persons were exposed and 7 186 (out of which 38% were children up to 14 years of age) got sick. Hospitalization was required for 1 603 of patients. The most frequent etiological agent was Salmonella sp. – 37,6%, 3 and 28,4% of cases). Viruses were responsible for 22,5% of outbreaks and 28,6 % of cases (And among them rotaviruses- 10,8% of outbreaks and 5,2% of cases and noroviruses- 11,1% of outbreaks and 23,3% of cases). In 27,5% of outbreaks no etiological agent was found. Just as in 2015 private household was the most frequent place of an outbreak- 323 outbreaks (47,5%), and after that- hospital- 135 outbreaks (19,9%). In 2016 in more than 81% of outbreaks no vehicle was found and in remaining the most frequent vehicle were eggs and egg products) (25% of outbreaks of known vehicle). The increase in the both percentage of reported salmonellosis cases among the group of bacterial foodborne infections and the increase of foodborne outbreaks of Salmonella Enteritidis etiology along with the fact of the occurrence of large, multistate outbreak of this etiology with Polish eggs as a vehicle indicates an alarming situation and the necessity of microbiological surveillance enchantment in relation to abovementioned products. Moreover an increase in the percentage of unknown etiology outbreaks, in which clinical symptoms of cases suggest viral etiology indicates the need for more frequent testing oriented for those pathogens during epidemiological investigations.