ABSTRACT
The present study was conducted to investigate the prevalence and diversity of Arcobacter and Campylobacter spp. in 298 stool samples of patients with diarrhoea, collected from 22 Portuguese hospitals, between September and November 2012. Detection of Arcobacter and Campylobacter spp. was performed using molecular-based detection techniques, such as real-time fluorescence resonance energy transfer PCR, species-specific PCR, and sequencing of amplified PCR products. Overall, 1.3% of the samples were positive for Arcobacter butzleri and 0.3% for Arcobacter cryaerophilus. Campylobacter spp. were found in 31.9% of diarrhoeic faeces. Campylobacter jejuni and Campylobacter concisus were the most prevalent species (13.7% and 8.0%, respectively). The prevalence of Arcobacter and Campylobacter spp. was significantly different between children and adults (39.7% versus 22.8%, P = 0.003). We underline the high prevalence of these pathogens in diarrhoeal samples among Portuguese patients, with particular relevance in the paediatric age group.
Subject(s)
Arcobacter/isolation & purification , Campylobacter/isolation & purification , DNA, Bacterial/isolation & purification , Diarrhea/microbiology , Real-Time Polymerase Chain Reaction/methods , Adolescent , Adult , Aged , Aged, 80 and over , Arcobacter/classification , Campylobacter/classification , Campylobacter Infections/diagnosis , Child , Child, Preschool , Feces/microbiology , Female , Gram-Negative Bacterial Infections/diagnosis , Humans , Infant , Infant, Newborn , Male , Middle Aged , Portugal , Sequence Analysis, DNA , Young AdultABSTRACT
Giardia and Cryptosporidium are the most frequent enteric protozoa causing gastroenteritis in humans worldwide. Intense recreational activity at Portuguese river beaches triggered the opportunity for a 2-year seasonal survey of 19 large river basin beaches. A total of 74 samples were collected and processed according to USEPA Method 1623 to detect Cryptosporidium and Giardia (oo)cysts. Faecal indicators (thermotolerant/total coliforms, Escherichia coli, and enterococci) and physicochemical parameters were also analysed according to the EU Bath Water Directive (BWD). Results pointed to a widespread presence of these protozoa at Portuguese river beaches. The percentage of samples testing positive for Giardia and Cryptosporidium were 85 and 82% respectively, with no significant differences between wet and dry seasons (p > 0.05). Although Portuguese river beaches present a very low exposure risk for infection with Giardia and Cryptosporidium (under 10(-3)), a few particular cases revealed values over 0.2%, and were related to stormy wet events. The correlation between levels of Giardia and thermotolerant coliforms, E. coli and enterococci, was high (r ≥ 0.87, p < 0.001), suggesting the need to carry out specific procedures for the detection of Giardia and Cryptosporidium whenever the values of those faecal indicators approach the maximum allowed level of the EU BWD.
Subject(s)
Cryptosporidium/isolation & purification , Giardia/isolation & purification , Rivers/parasitology , Cluster Analysis , Portugal , Public Health , Risk Factors , Water Microbiology , Water PollutantsABSTRACT
BACKGROUND: Giardia duodenalis is a widespread parasite of mammalian species, including humans. The prevalence of this parasite in children residing in Portugal is currently unknown. This study intended to estimate G. duodenalis infection prevalence and identify possible associated risk factors in a healthy paediatric population living in the District of the Portuguese capital, Lisbon. METHODS: Between February 2002 and October 2008, 844 children were randomly selected at healthcare centres while attending the national vaccination program. A stool sample and a questionnaire with socio-demographic data were collected from each child. Giardia infection was diagnosed by direct examination of stools and antigen detection by ELISA. RESULTS: The population studied revealed a gender distribution of 52.8% male and 47.2% female. Age distribution was 47.4% between 0-5 years and 52.6% between 6-15 years.The prevalence of Giardia infection was 1.9% (16/844) when estimated by direct examination and increased to 6.8% (57/844) when ELISA results were added. The prevalence was higher among children aged 0-5 years (7.8%), than among older children (5.8%), and was similar among genders (6.9% in boys and 6.5% in girls). The following population-variables were shown to be associated risk factors for G. duodenalis infection: mother's educational level (odds ratio (OR)= 4.49; confidence interval (CI): 1.20-16.84), father's educational level (OR = 12.26; CI: 4.08-36.82), presence of Helicobacter pylori infection (OR = 1.82; CI: 1.05-3.15), living in houses with own drainage system (OR = 0.10; CI: 0.02-0.64) and reported household pet contact, especially with dogs (OR = 0.53; CI: 0.31-0.93). CONCLUSION: The prevalence of giardiasis in asymptomatic children residing in the region of Lisbon is high. Several risk factors were associated with Giardia prevalence and highlight the importance of parents' education and sanitation conditions in the children's well being. The association between G. duodenalis and H. pylori seems an important issue deserving further investigation in order to promote prevention or treatment strategies.
