EPI• NEWS NATIONAL SURVEILLANCE OF COMMUNICABLE DISEASES Editor: Susanne Samuelsson Dept. of Epidemiology Tel.: +45 3268 3268 • Fax: +45 3268 3874 Statens Serum Institut • 5 Artillerivej • DK 2300 S www.ssi.dk • [email protected] • ISSN: 1396-4796

RESPIRATORY SYNCYTIAL VIRUS No. 24, 2002 Respiratory syncytial virus (RSV) is Table 1. No. of specimens positive tions collected by nasal suction or the most common cause of acute lo- for respiratory syncytial virus (RSV) swab can be used, but this method is wer respiratory tract in by age, M/F ratio and incidence per less sensitive. RSV is detected in cli- small children. RSV is a single- 105, 1998-2000 nical microbiological departments by strained RNA virus, belonging to the immunofluorescence, ELISA and Age M/F Incidence pneumovirus genus of the Paramyxo- 5 PCR. Quick tests (20 minutes) are a viridae family. The virus is divided (yrs) No.ratio per 10 little less sensitive. into two types, A and B, each of <1 3782 1.4 1892.6 which has several subtypes. 1 1336 1.3 659.1 Treatment 2 337 1.4 162.6 There is no sure and efficient treat- Occurrence 3-4 114 1.1 27.1 ment for RSV . Ribavirin has RSV was isolated for the first time 5-9 30 1.0 3.0 been used for the treatment of child- from American children with lower ren at risk of severe course of the in- 10-19 13 1.6 0.7 respiratory tract infections in 1957. fection, particularly in United States, A total of 90% of all children have 20-29 16 1.7 0.7 but serious questions have been rai- had one, and 50% have had two RSV 30-39 13 0.3 0.5 sed about the effect. This agent is infections before the age of two. 40-64 24 1.7 0.5 currently used in only in Every year during the RSV season, 65+ 7 1.3 0.3 RSV infection in patients with severe from November to May, approx. Unknown 23 - - immune deficiency. Treatment of pa- 1,500 Danish children are admitted Total 5695 1.3 35.7 tients with adequate immune functi- with RSV infection, and many more on consists of suction, adequate nu- are seen in general practice or loo- trition and respiratory support. In the ked after at home because of the in- Transmission event of bronchospasm, a beta-2 fection. A study from eastern Den- Virus is secreted up to three weeks agonist can be tried, and antibiotics mark showed that 3.4% of all chil- after onset of illness. Infection usual- are given in the event of secondary dren < 6 months were admitted with ly takes place by inoculation in the bacterial infection. RSV infection during the winter sea- nose and eyes with secretion drop- son 1995-96. At special risk of a lets from RSV-infected people, or Prevention course of illness requiring admission with secretions deposited on surfa- A safe and effective is not are premature children, children ces. Virus-containing secretions can yet available. However, the addition with chronic respiratory illness, con- remain infectious for more than six of specific antibodies may reduce the genital heart disease and immuno- hours on a smooth surface, and on risk of admission of children at risk deficient children In a Danish study cloth and paper for around 30 min- of severe course of illness. Studies comprising 240 children with a birth utes. have shown that nosocomial infec- weight under one kilogram or gesta- tion with RSV can be reduced by tional age less than 28 weeks, it was Symptoms hand washing and/or spraying with found that the risk of admission for Incubation time is two to eight days. spirit, use of aprons and gloves and RSV infection during the first two The primary infection is seldom by isolation of RSV-infected patients years of life was 18%. However, asymptomatic, and the most common during admission. It may be appro- most children with RSV infection re- manifestation is upper respiratory priate to wash items such as toys and quiring admission are otherwise tract infection with rhinitis, but otitis stethoscopes, or to spray them with healthy and born at term. Risk fac- media and laryngitis also occur. spirit, as these may function as vec- tors among these children are age < Among 25-40% of primarily infected tors for micro-organisms. 6 months, male gender, low socio- children, the infection spreads to the (L. G. Stensballe, Department of economic status, many people per lower airways leading to bronchioli- Epidemiology Research, square metres in the home, tobacco tis or pneumonia with dyspnoea, K. Kristensen, Paediatric Clinic II, smoke, siblings, nursery care and wheezing, intercostal and subcostal Copenhagen University Hospital) possibly familial predisposition to al- recession, and in the smallest chil- lergic illness. In western countries, dren possibly apnoeic episodes. The Surveillance the mortality among children as a re- disease usually lasts two to three Since October 1998, a number of cli- sult of RSV infection is very low, < weeks. Complications may appear in nical microbiological departments 1%. RSV also causes illness among the form of bacterial pneumonia or have monthly reported laboratory- adults and among the elderly even otitis media. Up to 20% of children confirmed RSV infections to the De- death. In connection with a project who have had a serious RSV infec- partment of Epidemiology. The result currently in progress, data has been tion are readmitted within a few of the reports for 1999-2002 is shown collected for all persons investigated years with asthmatic symptoms. It is in the diagram on the back. From for RSV infection in Denmark since undecided whether the relation be- this it can be seen that the epidemic 1995. During the period 1998-2000, tween serious RSV infection and hy- curve peaked in the period January- 19,495 specimens were investigated perreactive airways is causal or March. This voluntary reporting is for RSV, of which 5,695 (29%) were whether there exists a common pre- important, partially because interest positive. Age and gender distribution disposition. in RSV infection is increasing. of these is shown in table 1. Since (G. H. Kock-Hansen, S. Samuelsson, older children and adults are not of- Diagnosis Department of Epidemiology) ten investigated for RSV infection, The best test material for detection of data for these age groups is scarce in RSV is obtained by nasopharyngeal the table. suction or nasal lavage. Nasal secre- 12 June 2002 Patients with laboratory-diagnosed RSV, 1999-2002

No. 600

500

400

300

200

100

0 July Aug Sep Oct Nov Dec Jan Feb Mar Apr May June

1999/2000 2000/2001 2001/2002

Reported from the following Clinical Microbiology Departments: Aalborg Hospital (South), Aarhus Municipal Hospital, Herning Central Hospital, Hvidovre Hospital, Odense University Hospital, Slagelse Central Hospital, Viborg Hospital, Dept. of Virology, Statens Serum Institut.

Patients with confirmed Listeria monocytogenes infection 1st quarter of 2002 compared with 1st quarter of 2001, and 2001, whole year

1st quarter 1st quarter Whole year 2002 2001 2001 Morther/child infection 2 1 3 Septicaemia 3 525 Meningitis 0 210 Other 0 00 Total 5 8 38

(Dept. of G-I Infections, Dept. of Clinical Microbiology)