Two nosocomial norovirus outbreaks in the neonatal intensive and intermediate care unit

Associations of infection control measures and norovirus outbreak outcomes in healthcare settings: a systematic review and meta-analysis

BACKGROUND

Although most norovirus outbreaks in high-income countries occur in healthcare facilities, information on associations between control measures and outbreak outcomes in these settings is lacking.

METHODS

We conducted a systematic review/meta-analysis to assess associations between norovirus outbreak control measures and outcomes in hospitals and long-term care facilities (LTCFs), globally. Using regression analyses stratified by setting (hospital/LTCF), we compared durations, attack rates, and case counts for outbreaks in which control measures were reportedly implemented to those in which they were not.

RESULTS

We identified 102 papers describing 162 norovirus outbreaks. Control measures were reportedly implemented in 118 (73%) outbreaks and were associated with 0.6 (95% CI: 0.3-1.1) times smaller patient case counts and 0.7 (95% CI: 0.4, 1.0) times shorter durations in hospitals but 1.5 (95% CI: 1.1-2.2), 1.5 (95% CI: 1.0-2.1) and 1.6 (95% CI: 1.0-2.6) times larger overall, resident and staff case counts, respectively, and 1.4 (95% CI: 1.0-2.0) times longer durations in LTCFs.

CONCLUSIONS

Reported implementation of control measures was associated with smaller/shorter outbreaks in hospitals but larger/longer outbreaks in LTCFs. Control measures were likely implemented in response to larger/longer outbreaks in LTCFs, rather than causing them. Prospective observational or intervention studies are needed to determine effectiveness.

Laser Acupuncture for Neonatal Abstinence Syndrome: A Randomized Controlled Trial

BACKGROUND

Neonatal abstinence syndrome (NAS) is usually treated with opiate derivatives and supported with nonpharmacological treatment.

METHODS

This prospective, randomized, controlled, blinded, single-center study was carried out between March 2009 and November 2014. Newborn infants diagnosed with NAS after maternal opioid substitution therapy were eligible for inclusion. Infants were randomly allocated to the acupuncture group (combining laser acupuncture and pharmacological therapy of morphine and phenobarbital) or control group (pharmacological therapy alone). Laser acupuncture was performed with a LABpen MED 10 (675 nm/10 mW) at 5 ear and 4 body acupuncture points, bilaterally, and sessions were repeated every day. The primary outcome measure was duration of oral morphine therapy for NAS. Secondary outcomes included highest single Finnegan score, time to highest single Finnegan score, maximum amount of oral morphine solution (in milliliters per kilogram and milligrams per kilogram), time to maximum amount of oral morphine solution, and length of hospital stay.

RESULTS

Twenty-eight newborns (14 in each group) were eligible for analysis. Duration of oral morphine therapy was significantly reduced in the acupuncture group compared with the control group (28 vs 39 days, respectively, P = .019). In addition, we observed a significantly reduced length of hospital stay in the acupuncture group compared with the control group (35 days [interquartile range 25 to 47] vs 50 days [36 to 66], P = .048).

CONCLUSIONS

Adjunctive laser acupuncture significantly reduced the duration of morphine therapy in newborns with NAS.

Evaluation of rapid immunochromatographic tests for norovirus in neonatal and infant faecal specimens

OBJECTIVES

To compare the diagnostic performance of two norovirus rapid immunochromatographic kits (QuickNavi(®)-Norovirus [QN] and QuickNavi®-Norovirus 2 [QN2]; Denka Seiken, Niigata, Japan) for neonatal and infant faecal specimens.

METHODS

Monthly faecal samples were collected from infants from birth to 12 months of age, and tested for norovirus using QN and QN2. Real-time reverse transcription polymerase chain reaction (RT-PCR) was used as the gold standard for norovirus detection. The diagnostic performance of the kits was calculated.

RESULTS

A total of 343 specimens from 81 infants were analysed. In all samples, the specificity of QN and QN2 was 80% (275/343) and 99% (339/343), respectively. In infants aged <1 month, the specificity of QN was 33% (23/70), increasing to 93% at 4 months of age. Specificity of QN2 was ≥94% in infants between 0 and 12 months of age.

CONCLUSIONS

QN2 offers improved performance and is more useful than QN for the diagnosis of norovirus infection in the neonatal and infant period.

Survey of neonatal unit outbreaks in North London: identifying causes and risk factors

BACKGROUND

This survey was undertaken after a number of neonatal unit (NNU) outbreaks were reported to the North London health protection teams (HPTs).

AIM

To determine the diversity of the outbreaks, ascertain potential sources and contributing factors, and identify the investigative procedures followed and control measures implemented.

METHODS

Using a structured questionnaire, information from the HPT database was collected for all NNU outbreaks reported between January 2010 and February 2011.

FINDINGS

Ten outbreaks were identified from seven hospitals in 14 months. There was one para-influenza outbreak, seven Staphylococcus aureus [including six meticillin-resistant S. aureus (MRSA)] outbreaks, and two Gram-negative outbreaks. Potential sources of transmission identified for the MRSA outbreaks were healthcare worker (HCW)-assisted transmission (N = 2) and mother-to-baby transmission with onward HCW-assisted transmission (N = 3). An environmental source with onward HCW-assisted transmission was documented for one of the Gram-negative outbreaks. Interventions included patient screening and enhanced cleaning (N = 10), isolating/cohorting affected neonates (N = 9), barrier nursing (N = 6), staff movement restrictions (N = 5), hand hygiene audits (N = 4), staff screening (N = 4), household contact screening (N = 3) and environmental sampling (N = 3). Potential contributing factors included inadequate staffing levels, cluttered unit, inadequate sterilization of communal milk-expressing equipment and inappropriate follow-up of MRSA results.

CONCLUSION

This survey determined the diversity of NNU outbreaks in North London, and highlighted the importance of a multi-faceted approach to outbreak control. These data will assist in the development of clinical standards for the prevention, control and reporting of NNU outbreaks, and guidance for best practice in NNUs.

Norovirus genogroup II gastroenteritis in hospitalized children in South India

The distribution of norovirus (NoV) genogroup II in children < 5 years of age admitted to a south Indian hospital with diarrhea was investigated. Viral RNA extracted from 282 stool samples were screened for NoV GII and positive amplicons sequenced. Twenty-eight (9.9%) had NoV GII infection with a median age of 6 months, with more severe episodes of diarrhea among infected (median Vesikari score 13, interquartile range [IQR] 10-15) than children without infection (median score 10, IQR 8-13, P = 0.002). The study documents NoV GII infections as an important cause of gastroenteritis and the genetic diversity of circulating strains.

Infecciones nosocomiales en pediatría

Numerosas son las particularidades de la población pediátrica que deben intervenir, en nuestra opinión, en el control de las infecciones nosocomiales. Los riesgos y los agentes patógenos responsables son diferentes en función del tipo de población (prematuros, recién nacidos, otros). Además, esta población, que comparte los mismos factores de riesgo de infecciones nosocomiales que la población adulta (hospitalización en reanimación, cateterismos, etc.), se distingue no sólo por la inmadurez del sistema inmunitario de los recién nacidos, sino también por la multiplicidad de los participantes, desde los sanitarios hasta los padres, pasando por los educadores y los acompañantes (visitantes de todo tipo, etc.) necesarios para el desarrollo conductual y emocional del niño. Además, es importante subrayar el aumento del riesgo ligado a los contactos frecuentes, cercanos e íntimos que están parcial e incluso totalmente ausentes en el ámbito hospitalario «adulto». Así como existen riesgos de transmisión cruzada a través del principal vector constituido por los sanitarios, el control del riesgo no puede excluir a los educadores, a los acompañantes, a los padres y a los mismos niños. Si el riesgo en la esfera adulta está limitado a las actividades médicas, en la esfera pediátrica se comparte con las demás actividades (juegos, enseñanza, etc.), que con frecuencia son comunes. Todos estos riesgos son todavía mayores debido a la prevalencia de los agentes patógenos como los virus (respiratorios y digestivos), la frecuencia de las antibioticoterapias y la dificultad de los diagnósticos etiológicos, dada la inespecificidad de los signos clínicos y la actitud diagnóstica poco o nada invasiva. De esta manera, el control del riesgo infeccioso nosocomial se resume en los siguientes elementos: un reservorio importante y difícilmente identificable, numerosos vectores potenciales, una población expuesta de manera variable al riesgo, todo ello sin olvidar las necesidades emocionales de los niños y los comportamientos «culturales».

A review of nosocomial norovirus outbreaks: infection control interventions found effective

The purpose of this study was to review documented outbreaks of enteric illness associated with nosocomial norovirus infections and to identify modes of transmission, morbidity and mortality patterns, and recommendations for control. Searches of electronic databases, public health publications, and federal, state/provincial public health websites were completed for 1 January 2000 to 31 December 2010. Computer-aided searches of literature databases and systematic searches of government websites identified 54 relevant outbreak reports. Transmission routes included person-to-person (18.5%), foodborne (3.7%) and in the majority (77.8%) the route was unknown. Actions taken during the outbreak to control infection included restricting the movements of patients and staff (22.5%), enhanced environmental cleaning (13.6%) and hand hygiene (10.3%). Rapid identification of norovirus outbreaks in hospitals is vital for the immediate implementation of infection control measures and isolation of infected individuals in this mainly immunocompromised population. Studies that statistically evaluate infection control measures are needed.

Emerging viral infections in neonatal intensive care unit

Nosocomial infections are the most important cause of morbidity and mortality among neonates and mostly in infants admitted to neonatal intensive care units (NICU). The total number of neonates who develop nosocomial infections per admission varies from 6.2 to 30%. The role of nosocomial virus infections is generally neglected in the actual epidemiologic scenario mostly due to the lack of data in the medical literature. Based on a worldwide database of health care-associated outbreaks (http://www.outbreak-database.com) we performed an analysis of the incidence, type of pathogens and clinical features of neonatal viral outbreaks especially those reported in NICUs. We also describe, as an example of emerging virus in NICU, a Norovirus outbreak along with clinical presentation that varies from mild to moderate clinical symptoms like vomiting, gastric remainder, diarrhoea, abdominal distension or severe presentation like necrotizing enterocolitis. and measures implemented for terminating the outbreak. In conclusion, our study analyses the viral origins of nosocomial infections in NICU and underline that the role of viral agents in neonatal nosocomial infections needs to be further investigated even in diseases traditionally considered of bacterial origin like necrotizing enterocolitis.

An automated genotyping tool for enteroviruses and noroviruses

BACKGROUND

Molecular techniques are established as routine in virological laboratories and virus typing through (partial) sequence analysis is increasingly common. Quality assurance for the use of typing data requires harmonization of genotype nomenclature, and agreement on target genes, depending on the level of resolution required, and robustness of methods.

OBJECTIVE

To develop and validate web-based open-access typing-tools for enteroviruses and noroviruses.

STUDY DESIGN

An automated web-based typing algorithm was developed, starting with BLAST analysis of the query sequence against a reference set of sequences from viruses in the family Picornaviridae or Caliciviridae. The second step is phylogenetic analysis of the query sequence and a sub-set of the reference sequences, to assign the enterovirus type or norovirus genotype and/or variant, with profile alignment, construction of phylogenetic trees and bootstrap validation. Typing is performed on VP1 sequences of Human enterovirus A to D, and ORF1 and ORF2 sequences of genogroup I and II noroviruses. For validation, we used the tools to automatically type sequences in the RIVM and CDC enterovirus databases and the FBVE norovirus database.

RESULTS

Using the typing-tools, 785(99%) of 795 Enterovirus VP1 sequences, and 8154(98.5%) of 8342 norovirus sequences were typed in accordance with previously used methods. Subtyping into variants was achieved for 4439(78.4%) of 5838 NoV GII.4 sequences.

DISCUSSION AND CONCLUSIONS

The online typing-tools reliably assign genotypes for enteroviruses and noroviruses. The use of phylogenetic methods makes these tools robust to ongoing evolution. This should facilitate standardized genotyping and nomenclature in clinical and public health laboratories, thus supporting inter-laboratory comparisons.

Norovirus as a foodborne disease hazard

Norovirus (NoV) is the most common cause of infectious gastroenteritis in the world. Gastroenteritis caused by bacterial and parasitic pathogens is commonly linked to food sources, but the link between NoV and contaminated foods has been more difficult to establish. Even when epidemiological information indicates that an outbreak originated with food, the presence of NoV in the suspect product may not be confirmed. If food is found to contain a common strain of NoV that circulates widely in the community, it is not possible to use strain typing to link the contamination to patient cases. Although food is certainly implicated in NoV spread, there are additional person-to-person and fomite transmission routes that have been shown to be important. NoV has an extremely low infectious dose, is stable in the environment, and resists disinfection. Cell culture methods are not available, so viability cannot be determined. Finally, many NoV outbreaks originate with when an infected food handler contaminates ready-to-eat food, which can be interpreted as foodborne or person-to-person transmission. This review will discuss both the physical characteristics of NoVs and the available epidemiological information with particular reference to the role of foods in NoV transmission.

Recognition and prevention of hospital-associated enteric infections in the intensive care unit

The objectives of this article were to review the causes and extent of hospital-associated infectious diarrhea and associated risks in the general hospital ward and intensive care unit (ICU), to compare microorganisms with similar symptoms to aid in recognition that will lead to timely and appropriate treatment and control measures, and to propose infection prevention protocols that could decrease human process errors in the ICU. This literature review describes epidemiology, comparison of microbial characteristics for potential hospital-associated enteric pathogens, diagnosis, and prevention, especially if important in the ICU, and particularly in regard to Clostridium difficile. Enteric organisms that most commonly cause hospital-associated infectious diarrhea in acute care settings and the ICU are C. difficile, rotavirus, and norovirus, although others may also be important, particularly in developing countries. To recognize and control infectious diarrhea successfully in the ICU, intensivists should be aware that epidemiology, risks, and prevention measures may differ between these microorganisms. In addition, intensivists should be ready to implement systems changes related to notification, isolation precautions and prevention, and environmental cleaning in the ICU.

Genogroup IIb norovirus infections and association with enteric symptoms in a neonatal nursery in southern India

Noroviruses (NoVs) are increasingly recognized as an important cause of acute gastroenteritis in children worldwide. However, there are limited data on the role of NoVs in neonatal infections and disease. The objectives of the present study were to determine the prevalence of NoVs in neonates with gastrointestinal disease using a case-control study design and to characterize the NoV strains infecting neonates. A total of 309 fecal samples from 161 neonates with gastrointestinal symptoms and 148 asymptomatic controls were screened for genogroup II (GII) NoV using reverse transcription-PCR. A subset of PCR-positive amplicons for the polymerase and capsid regions was sequenced. NoV was detected in 26.2% of samples, with the rate of detection being significantly higher among symptomatic neonates (60/161, 37.2%) than asymptomatic neonates (24/148, 14.1%) (P < 0.001). On the basis of sequencing of 29 strains, a single NoV strain, GIIb, was identified to be the predominant (27/29, 93.1%) cause of neonatal infections. Coinfection with rotavirus was seen in nearly one-third of symptomatic neonates. The study demonstrates a high prevalence of NoV infections in neonates and indicates that coinfection with rotavirus may result in significantly more gastrointestinal disease in this population.