Salmonella enterica serotypes and antibiotic susceptibility in New Zealand, 2002-2007.

We analysed the serotypes and antibiotic susceptibility of 1560 human and 1505 non-human Salmonella isolated in New Zealand (NZ) between 2002 and 2007. The most common serotypes in humans were Salmonella enterica serovar Typhimurium, S. Enteritidis, S. Brandenburg and S. Infantis. Over the 6-year period human cases due to S. Agona and S. Enteritidis increased and cases due to S. Typhimurium decreased. The most common serotypes from non-human sources were S. Typhimurium, S. Brandenberg, S. Hindmarsh and S. Infantis, and there were no significant changes over time. More isolates were non-susceptible to streptomycin than to any other antibiotic. Almost all isolates were susceptible to ciprofloxacin and gentamicin. There were significant trends of increasing non-susceptibility to streptomycin and sulfonamides in isolates from human and non-human sources, while ampicillin, tetracycline and multidrug non-susceptibility also increased in human isolates. Despite these increases, rates of antibiotic non-susceptibility in Salmonella in NZ are still lower than in many international settings.

Risk factors for the initial symptomatic giardia infection in a cohort of young Arab-Bedouin children.

BACKGROUND: Giardiasis is a common protozoan infection with clinical manifestations in children ranging from asymptomatic carriage to persistent diarrhoea with malabsorption. It can lead to growth and developmental retardation. AIM: The study evaluated risk factors for the initial symptomatic giardiasis (SG) episode among Arab-Bedouin children in Israel. METHODS: A community-based, prospective cohort study was conducted in Rahat, a Bedouin township in southern Israel. Infants (n=238) were followed by weekly visits from birth to age 18 months. Giardia infection was identified by antigen detection in faecal specimens. RESULTS: Approximately 26% of children experienced one or more SG episode. Mean (SD) age for first SG episode was 12.3 (3.3) months, with 95% of episodes occurring in children >6 months of age. Risk for the first SG in children >6 months of age was associated with it being spring or summer [odds ratio (OR) 6.16, p<0.001], exposure to livestock (OR 4.89, p=0.002) and prior infection with entero-aggregative Escherichia coli (EAEC) (OR 1.12 for each additional percentage in stool prevalence, p=0.02). Weight-for-age Z-scores at age 6 months were inversely related to SG risk (OR 0.62 for each unit increase in Z-score, p=0.029). CONCLUSIONS: Giardiasis is an important cause of diarrhoea in Bedouin children. Increased risk of SG in spring/summer might be linked to environmental conditions or seasonal dietary practices which increase virulence or transmission. SG in those exposed to livestock suggests that there are zoonotic risk factors or that hygiene is a causal factor. The association between EAEC infection and SG warrants further investigation.

Pneumococcal nasopharyngeal colonization in young South Indian infants.

BACKGROUND: Streptococcus pneumoniae is the most frequent bacterial cause of morbidity and mortality in young children. Bacteria carried in the nasopharynx of healthy children reflect the prevalent strains circulating in the community. METHODS: We recruited 464 newborns from a rural area in South India with endemic vitamin A deficiency. Nasopharyngeal specimens were collected from each infant at ages 2, 4 and 6 months. RESULTS: Fifty-four percent of study infants were colonized by age 2 months, with 64.1 and 70.2% carriage prevalence at ages 4 and 6 months, respectively. The odds of carriage at 2 months were significantly increased in female infants, infants living in a household in which 20 or more cigarettes were smoked each day, infants whose mothers had less than 1 year of schooling and infants fed colostrum. At age 4 months infants having 2 or more siblings <5 years of age were at significantly increased risk of carriage. At age 6 months none of the potential risk factors examined achieved statistical significance, but maternal night blindness increased the risk of colonization 3-fold. The odds of carrying a PncCRM197 vaccine serotype were increased among infants born to mothers who experienced night blindness during pregnancy. The most prevalent serogroups/types during the first 6 months of life were 6, 9, 10, 11, 14, 15, 19, 23 and 33, accounting for 76.7% of all serotyped isolates. CONCLUSIONS: South Indian infants experience high rates of pneumococcal carriage during the first 6 months of life, which may partially explain their increased risk for pneumonia.

Subclinical vitamin A deficiency in Israeli-Bedouin toddlers.

OBJECTIVE: This study was designed to estimate the prevalence of and evaluate risk factors for subclinical vitamin A deficiency in Arab-Bedouin children at age 18 months, followed from birth. DESIGN: Community-based, prospective, cohort study conducted in Rahat, a large Arab-Bedouin township, located near the city of Beer Sheva in the Negev region of southern Israel. SUBJECTS: Healthy Bedouin infants (n=117) from the township, born at Soroka University Medical Center (SUMC) in Beer Sheva, were randomly recruited at birth. Enrollment was restricted to well infants born weighing >2500 g at birth. RESULTS: More than 15% of the children had serum retinol concentrations below 0.7 micromol/l. Male sex (odds ratio (OR) 4.17 [1.14-15.32], P=0.031), stunting at age 12 months (OR 10.09 [2.00-50.97], P=0.05) and warm season at age 18 months (OR 6.20 [1.36-28.28], P=0.018) were associated with vitamin A deficiency. Maternal education decreased the risk of vitamin A deficiency (OR 0.81 [0.68-0.95], P=0.011). CONCLUSIONS: Study results indicate a significant vitamin A deficiency problem among Bedouin children. Deficiency may be prevented by increasing dietary intake of vitamin A, especially during the warm season. Other interventions include preventing and controlling diarrheal diseases in order to avert nutritional stunting, and providing nutritional education to women of childbearing age. SPONSORSHIP: This study received financial support from the National Institute of Allergy and Infectious Diseases (AI-26497), the US-Israel Bi-national Science Foundation (BSF 90-00257), and the National Academy of Sciences/Institute of Medicine (AID/ANE 0158-G-SS-9035-00).

Risk factors for antibiotic-resistant E. coli in children in a rural area.

We surveyed antimicrobial susceptibility in faecal Escherichia coli in primary schoolchildren in rural Tamil Nadu, India. Resistance profiles of E. coli samples from local water sources were also obtained. We investigated sociodemographic characteristics as risk factors for resistance and local paediatric prescription patterns. In 119 stool samples, carriage of resistance to 1 antibiotic was 63% and multiple drug resistance was 32%. Resistance outcomes were associated with school of attendance, having a sibling attend the same school, younger age, and less crowded households. Eight of nine water samples were resistant to > or =1 antibiotic. Recent history of medication use was not associated with resistance carriage. Resistance patterns may have been influenced by local paediatric prescription patterns and veterinary antibiotic use. Frequent, low-cost surveillance of commensal resistance can guide development of locally appropriate treatment guidelines. School-based hygiene programmes should be considered as means of limiting the spread of antibiotic resistance.

Nasopharyngeal carriage of resistant pneumococci in young South Indian infants.

Streptococcus pneumoniae is the leading bacterial cause of life-threatening infections in infants. Although antibiotic resistance affects management of pneumococcal infections, few data on patterns of resistance are available for India. We examined nasopharyngeal carriage of antibiotic-resistant pneumococci in 464 South Indian infants between 2 and 6 months. Newly acquired serotypes were screened for susceptibility to cotrimoxazole, erythromycin and penicillin using disk diffusion. Cumulative prevalence of pneumococcal carriage rose from 53.9% at 2 months to 70.2% at 6 months. The prevalence of strains that were not susceptible to penicillin, cotrimoxazole and erythromycin was 34, 81.1 and 37.2%, respectively. Carriage of erythromycin non-susceptible strains declined significantly between ages 4 months and 6 months (44.1 vs. 10.7%). More than 87% of the isolates screened were non-susceptible to > or = 1 antibiotic. Serogroups/types that were most frequently non-susceptible to 1 or more antibiotics were 6, 9, 14, 19 and 23. Less than 1% of the isolates were multi-drug resistant. Widespread use of antibiotics in South India has resulted in S. pneumoniae becoming non-susceptible to some commonly used antibiotics. Monitoring trends in antibiotic susceptibility and making antibiotics available only through prescription from a health care worker may slow the spread of resistant pneumococci and improve management of pneumococcal infections in South India.

Vitamin A supplementation at birth delays pneumococcal colonization in South Indian infants.

Nasopharyngeal colonization is a risk factor for pneumococcal disease, a leading cause of complications and death in infants. We assessed the impact of vitamin A supplementation in reducing pneumococcal colonization in infants from an area with endemic vitamin A deficiency. We recruited 464 2-mo-old infants from a rural area in South India. Infants were randomly assigned to receive two 7000-microg retinol equivalent doses of vitamin A (n = 239) or placebo (n = 225) orally at birth, and nasopharyngeal specimens were collected at ages 2, 4 and 6 mo. We studied the effect of vitamin A on culture-confirmed pneumococcal colonization and on the distribution of pneumococcal serotypes. Analyses were conducted by intention-to-treat. The risk of colonization among infants aged 4 mo who were not colonized by age 2 mo was significantly reduced in the vitamin A group compared with the placebo group [odds ratio 0.51 (0.28, 0.92), P = 0.02). The odds of colonization were 27% lower in the treatment group than in the placebo group [odds ratio 0.73 (0.48, 1.1), P = 0.13]. No differences were detected in the prevalence of invasive serotypes. The risk of colonization with penicillin-resistant isolates was 74% lower in the vitamin A group than in the placebo group at 2 mo of age. However, the prevalence of penicillin-resistant isolates was only 4%. Neonatal vitamin A supplementation may play a role in lowering morbidity rates associated with pneumococcal disease by delaying the age at which colonization occurs.