Clinical Patterns and Risk Factors for Pneumonia Caused by Atypical Bacteria in Vietnamese Children.

OBJECTIVE: To investigate clinical characteristics and risk factors for atypical community-acquired pneumonia (CAP) in children. METHODS: Multiplex polymerase chain reaction and specific IgM determination were used to detect atypical bacteria in 661 hospitalized children aged 1-15 years with CAP. Clinical and epidemiological patterns were compared between typical and atypical CAP. RESULTS: Children in atypical CAP group manifested significantly lower rates of wheezing, bronchial rales, and interstitial pneumonia and showed higher rates of asthma history, headache, chest pain, and lobar pneumonia . Age group, season of disease onset, asthma history, duration of symptom onset to hospital admission, and radiological findings were the significant risk factors for atypical CAP on multivariate logistic regression analysis. CONCLUSIONS: The clinical characteristics and risk factors can be used to identify a child at high risk of atypical CAP.

Retraction: Pneumonia in Vietnamese Children Aged 1 to 15 years Due to Atypical Pneumonia Causative Bacteria: Hospital-Based Microbiological and Epidemiological Characteristics.

This article has been retracted by the authors under the agreement between the Editor-in-Chief, Masayuki Saijo and authors.

First report on prevalence and risk factors of severe atypical pneumonia in Vietnamese children aged 1-15 years.

BACKGROUND: Atypical pathogens such as Mycoplasma pneumoniae, Chlamydophila pneumoniae, and Legionella pneumophila are increasingly recognized as important causes of community acquired pneumonia (CAP) worldwide. Such etiological data for Vietnam is scarce and clinical doctors lack accurate information on which to base their diagnosis and treatment of pneumonia. This study identifies the prevalence and risk factors of severe community acquired pneumonia due to these atypical pathogens (severe-ApCAP) in children aged 1-15 years with CAP in a pediatric hospital in Hanoi, Vietnam. METHODS: 722 hospitalized children with CAP were recruited for detecting those atypical pathogens, using multiplex PCR and ELISA. Clinical and epidemiological data were collected. Multivariate logistic-regression analyses were performed to evaluate the associations of potential risk factors with severe-ApCAP. RESULTS: Among 215 atypical pathogen-positive CAP cases, 45.12% (97/215) were severe-ApCAP. Among the severe-ApCAP group, 55.67% (54/97) cases were caused by pure atypical pathogens and 44.33% (43/97) resulted from a co-infection with typical respiratory pathogens. M. pneumoniae was the most common, with 86.6% cases (84/97) in the severe-ApCAP group, whereas C. pneumoniae and L. pneumophila were less frequent (6.19% and 7.22%, respectively). The highest rate of severe-ApCAP was in children younger than two years (65.98%). The differences related to age are statistically significant (P = 0.008).The factors significantly associated with severe-ApCAP were age (OR = 0.84, 95% CI = 0.75-0.93, P = 0.001), co-infection with typical bacteria (OR = 4.86, 95% CI = 2.17-10.9, P < 0.0001), co-infection with respiratory viruses (OR = 4.36, 95% CI = 1.46-13.0, P = 0.008), respiratory/cardiac system malformation (OR = 14.8, 95% CI = 1.12-196, P = 0.041) and neonatal pneumonia (OR = 11.1, 95% CI = 1.06-116, P = 0.044). CONCLUSIONS: Severe-ApCAP presented at a significant rate in Vietnamese children. More than 50% of severe-ApCAP cases were associated with pure atypical pathogen infection. M. pneumoniae appeared most frequently. The highest rate of severe-ApCAP was in children younger than two years. Younger age and co-infection with typical bacteria or viruses were the most significant risk factors, while respiratory/cardiac system malformation and neonatal pneumonia were additional potential risk factors, associated with severe-ApCAP in Vietnamese children.

Nitrate and bacterial contamination in well waters in Vinh Phuc province, Vietnam.

Measurements were made of the nitrate concentration and bacterial contamination of groundwater samples taken from both dug wells and bores in the commune of Hop Thinh', in the administrative district of Vinh Phuc, Vietnam. A significant number (18%) of samples had nitrate concentrations in excess of the WHO Guideline value for drinking water of 50 mg L(-1), with a higher proportion in the dug wells (29%) than the bores (3.8%). High concentrations of thermotolerant coliforms were found in many of the dug wells and even in the deeper drilled bores. At the time of the study no Shigella or other infectious organisms were found. There was no correlation between nitrate concentration and bacterial content and it is concluded that nitrate concentration is not a good indicator for bacterial contamination.

Microbiological quality of fish grown in wastewater-fed and non-wastewater-fed fishponds in Hanoi, Vietnam: influence of hygiene practices in local retail markets.

Mean water quality in two wastewater-fed ponds and one non-wastewater-fed pond in Hanoi, Vietnam was approximately 10(6) and approximately 10(4) presumptive thermotolerant coliforms (pThC) per 100 ml, respectively. Fish (common carp, silver carp and Nile tilapia) grown in these ponds were sampled at harvest and in local retail markets. Bacteriological examination of the fish sampled at harvest from both types of pond showed that they were of very good quality (2 - 3 pThC g(-1) fresh muscle weight), despite the skin and gut contents being very contaminated (10(2) - 10(3) pThC g(-1) fresh weight and 10(4) - 10(6) pThC g(-1) fresh weight, respectively). These results indicate that the WHO guideline quality of < or = 1000 faecal coliforms per 100 ml of pond water in wastewater-fed aquaculture is quite restrictive and represents a safety factor of approximately 3 orders of magnitude. However, when the fish from both types of pond were sampled at the point of retail sale, quality deteriorated to 10(2) - 10(5) pThC g(-1) of chopped fresh fish (mainly flesh and skin contaminated with gut contents); this was due to the practice of the local fishmongers in descaling and chopping up the fish from both types of pond with the same knife and on the same chopping block. Fishmonger education is required to improve their hygienic practices; this should be followed by regular hygiene inspections.

Rotavirus disease in young children from Hanoi, Vietnam.

BACKGROUND: Pathogen prevalences and antimicrobial susceptibilities are essential for the rational development of preventive strategies for diarrheal diseases, but little recent information from Vietnam is available. We prospectively studied the prevalence of enteric pathogens in children less than 5 years of age with acute diarrhea and in nondiarrhea controls in a city hospital in Hanoi, Vietnam for 1 year. METHODS: Enteric bacteria and viruses were detected by standard culture methods, and enzyme immunoassay in 291 cases and 291 controls. RESULTS: Detection rates of viral pathogens among cases and controls were 31% and 3% for rotavirus, 12% and 1% for astrovirus and 4% and 1% for adenovirus. For bacterial pathogens, Aeromonas, Shigella, Salmonella, Campylobacter and enterotoxigenic E. coli were isolated from cases and controls in 15% and 8%, 9% and 1%, 7% and 1%, 4% and 0%, and 3% and 0%, respectively. The isolation of bacterial and viral pathogens except for adenovirus was significantly lower in controls than cases. Fluoroquinolones were effective against most bacterial enteropathogens, but resistance was observed in 27% of Campylobacter isolates. CONCLUSIONS: Viral etiologic agents especially rotavirus were the most important cause of acute diarrhea in children less than 5 years of age in Hanoi. The burden of rotavirus in young children in Hanoi warrants consideration of using the recently released rotavirus vaccine.