Investigation and successful control of an echovirus 11 outbreak in neonatal intensive care units.

BACKGROUND: Echovirus 11 emerged as a predominant enterovirus strain and was associated with neonatal mortalities in Taiwan in 2018. We investigated an echovirus 11 outbreak in the neonatal intensive care units (NICUs) in a tertiary hospital in northern Taiwan and analyzed infection control efforts. METHODS: Between May and June 2018, an outbreak of 10 infants with echovirus 11 infections occurred in the NICUs. Comprehensive surveillance, including virus isolation, real-time reverse transcription-polymerase chain reaction (RT-PCR), and consequential degenerate hybrid oligonucleotide primer (CODEHOP) methods, were arranged for specimens (rectal or throat swabs), which were obtained from all contacts, newly admitted cases, and suspected cases during the outbreak since June 2. RESULTS: Ten cases were identified with echovirus 11 infection in this outbreak. Eight of these 10 confirmed cases were identified by viral isolation, and the remaining two cases were identified by RT-PCR surveillance. In addition to confirmed cases, the surveillance of 19 contacts, 47 newly admitted cases, and nine suspected cases showed negative results. All confirmed cases eventually recovered. CONCLUSION: RT-PCR and CODEHOP methods significantly shorten the time of laboratory diagnosis of enterovirus infection compared with conventional methods. The outbreak of echovirus 11 in the NICUs was caused by three imported cases and was successfully controlled by the implementation of isolation, rapid surveillance, reinforced disinfection, and infection control measures.

[Serous meningitis].

During the second half of the 1950s serous meningitis and other enterovirus-induced diseases played one of the leading roles in human pathology in the world. Since the introduction of oral poliomyelitis vaccine (OPV) into wide medical practice from the beginning of the 1960s and during the subsequent decades the number of epidemics and the morbidity level in enterovirus-induced diseases sharply dropped. This was probably due to the interference of enteroviruses circulating in nature and vaccine polioviruses in the intestine of vaccinated children. At the beginning of the XXI century a tendency towards a growth in the morbidity of serous meningitis of enterovirus etiology was noted. This growth was probably due to a sharp decrease in the level of revaccinations of children with OPV. At the age of 2 to 14 years, most affected by enteroviruses, children were not vaccinated with OPV and they were thus left unprotected. The materials on the epidemiology of serous meningitis and recommendations on etiological diagnosis, as well as on the patients hospitalization and the vaccination of children with OPV as a nonspecific antiepidemic measures based on the phenomenon of virus interference are presented.

Serum albumin inhibits echovirus 7 uncoating.

Echoviruses induce a wide spectrum of diseases in man, the most severe being meningitis. In neonates, however, a severe systemic infection can be observed, leading to death. Serum albumin is the most abundant protein in plasma and most interstitial fluids, and its functions include osmoregulation and transport and delivery of hydrophobic molecules such as fatty acids and steroids. The results of cold-synchronized one-step growth analysis of echovirus 7 infection and sucrose-gradient analysis of A-particles suggest that physiological concentrations of albumin block echovirus 7 infection by inhibiting uncoating. The blockage was reversible and was still effective when albumin was added 30 min after virus adsorption. Inhibition of uncoating was confirmed by using rhodanine, a known specific inhibitor of echovirus uncoating. After removal of the albumin blockage, addition of rhodanine perpetuated the inhibition. Serum and interstitial albumin concentrations may limit echovirus infection in vivo and thereby act as an extracellular determinant for echovirus tropism.

[Summer 1997 viral meningitis in children Frankfurt/Main--a discussion of the revised communicable disease control regulation]. / Virale Meningitiden bei Kindern in Frankfurt/M. im Sommer 1997--ein Diskussionsbeitrag zum Referentenentwurf des Infektionsschutzgesetzes.

According to the current law of preventing infectious diseases in Germany, bacterial as well as aseptic meningitis have to be reported to the health authorities, whereas according to the amendment aseptic meningitis will no longer be notifiable. In Summer 1997, 63 children with aseptic meningitis were reported to the local health authorities of Frankfurt compared with 4 or 5 per year during the preceding years. In 40% enterovirus, resp. ECHO-30 virus could be detected. The local health authorities gave detailed information on the medical relevance as well as necessary hygienic measures to the families and kindergartens. During the same time reports on aseptic meningitis increased to double compared with 1996, with hot spots in 4 defined regions in Bavaria, Hesse and in Northern Germany. According to these data the duty of notification of aseptic meningitis should be maintained, so that health authorities can inform the population and ensure good hygiene methods.

A community outbreak of echovirus infection associated with an outdoor swimming pool.

Forty-six people became ill with vomiting, diarrhoea and headache within days of an outdoor swimming pool opening for the summer season in a small seaside village. During the weekend of the outbreak, 185 tickets to the pool had been sold. It was found that 34 bathers were ill, and one subject had vomited into the pool. All other cases arose after this incident. The risk of infection was greatest among those who swallowed pool water (24/28 versus 10/17, p = 0.07). Echovirus 30 was isolated from the case who vomited into the pool and from six other cases. Normal chlorine levels had not been adequate to contain the infection risk from vomitus, and, in future, pool attendants witnessing such incidents should consider closing the pool to the public and seeking advice on superchlorination.

Vinyl versus latex gloves as barriers to transmission of viruses in the health care setting.

One type of vinyl and seven types of latex gloves without visual defects were tested with respect to their barrier function against high concentrations of three viruses of varying size: herpes simplex virus type 1 (HSV-1, 180 nm), human immunodeficiency virus type 1 (HIV-1, 100 nm), and echovirus type 9 (Echo 9, 25 nm). Viral suspensions of HSV-1 (10(8) TCD50/ml), HIV-1 (10(5) TCD50/ml), and echovirus type 9 (10(7.5)TCD 50/ml) were placed in an inverted glove finger immersed in media and maintained for 3 h at room temperature with sampling performed from outside the glove at 10 min, 30 min, 1 h, 2 h, and 3 h. No cytopathic effect (CPE) was identified after inoculation onto Vero cells or RhMK cells for HSV-1 and Echo 9, respectively, and reverse transcriptase activity was not detected in Hut 78 cells after inoculation of HIV-1 during any of the time intervals. Stretching of a glove finger for 18 h with repetition of the procedure with Echo 9 revealed no CPE. We conclude that under these experimental conditions, intact gloves act as effective barriers to the transmission of viral particles, including HIV in the health care setting.

Outbreak of echovirus 11 infection in hospitalized neonates.

Between July 18 and August 5, 1986, a cluster of echovirus 11 infections occurred in hospitalized neonates. Ten infants were affected and one died. All cases occurring after the index case were infants who were in the nursery for at least 1 day when the index patient was also present. Risk factors for secondary infection included low birth weight or gestational age and receipt of antibiotics, red blood cell transfusions, nasogastric intubation or gavage feedings. Because viral infection had not been suspected in the index patient, isolation measures were not instituted until after onset of secondary cases. We conclude that more severely ill infants receiving intensive levels of care are at increased risk for nosocomial enteroviral infection. These infants may have a greater likelihood of exposure to the virus and/or increased host susceptibility. Outbreaks caused by cross-infection may be preventable by early recognition of patients colonized or infected with potentially pathogenic agents and prompt institution of appropriate isolation measures.

Prevention of spread of echovirus 6 in a special care baby unit.

A case of fatal neonatal infection with enteric cytopathogenic human orphan virus (echovirus) type 6 is presented. The measures taken to prevent further spread of infection with special reference to the use of human normal immunoglobulin are described.

Use of normal immunoglobulin in an echovirus 11 outbreak in a special-care baby unit.

An epidemic of echovirus 11 infections occurred in the Cambridge special-care baby unit during August to October, 1982. There were 21 confirmed infections in babies; 1 died, 1 recovered after resection of a kidney, 5 had meningitis, and 6 had respiratory symptoms. Normal human immunoglobulin which contained antibody to echovirus 11 was administered intramuscularly (250 mg) to give protection. None of the children given immunoglobulin immediately after delivery (205 doses) developed symptoms or ill-effects. Serological studies reinforced earlier evidence for the protective action of antibody, and it is considered that immunoglobulin is a valuable safeguard for exposed newborn infants.