[Gonorrhea and syphilis from Russia to Norway]

In the 1990s, Russia has experienced a rapidly increasing incidence of syphilis and gonorrhoea. There are concerns of a spread of the epidemics to neighbouring Norway. From 1993 to 1998, 1,335 cases of gonorrhoea and 62 cases of syphilis were reported to the Norwegian notification system for infectious diseases. We studied cases with a Russian patient or source partner and cases acquired in Russia. 28 (2.1%) of gonorrhoea cases and 12 (19%) of syphilis cases had links to Russia. There was no time trend over the period. Ten gonorrhoea and three syphilis cases were from Finnmark, a sparsely populated county neighbouring Russia. Most patients were males over 30 years of age. So far, the gonorrhoea and syphilis epidemics in Russia have had minor impact in Norway. Thorough surveillance is still needed.

Perspective: a five-country analysis of the impact of four different Haemophilus influenzae type b conjugates and vaccination strategies in Scandinavia

Prior to vaccinations against invasive Haemophilus influenzae type b (Hib) diseases in Scandinavia, first initiated in Finland in 1986, the incidence of cases in those five countries was 49/100,000/year in 0- to 4-year-olds and 3.5/100,000 overall. During the following decade, Hib conjugates administered to young children had approximately 95% effectiveness, regardless of which conjugate was used, whether two or three primary doses were administered, and at what age in early infancy the first vaccination was given. The herd immunity effect has extended protection to older age groups. A similar effectiveness of different conjugates in five countries despite considerable diversity in approach suggests that the same impact would occur in other regions with comparable epidemiology. The Scandinavian experience supports the view that three primary vaccine doses are not imperative, thus suggesting that reducing doses of costly Hib vaccines would be one way to facilitate their usage in regions with limited resources.

[Communicable disease control in connection with international air traffic to Norway]

International air traffic has increased the risk of importation of infectious diseases to Norway. We have used notification data and a theoretical framework to assess the risk of importation and subsequent disemination of serious infectious diseases in Norway. Every year, a few cases of these diseases are imported to Norway, especially malaria, shigellosis and typhoid fever. A few secondary cases of enteric diseases may occur, but epidemics are unlikely. Counselling and immunisation of Norwegians going abroad is the first step in prevention. Secondly, health services all over the country should be able to diagnose imported diseases early and institute infection control measures. However, there is no need for concentrating resources for disease control at international airports in Norway.

[Surveillance of the HIV-epidemic in Norway]

Surveillance of HIV infection and AIDS is still a cornerstone in the efforts to prevent spread of HIV in Norway. The surveillance system aims at measuring the incidence and prevalence of HIV infection in the country. We describe the development of the surveillance from 1983 until 1996 based on the National Notification System for Infectious Diseases. New cases of HIV infection are reported anonymously but cases of AIDS are reported with name. Key information on each case includes age, gender, residence and the most likely time, place and route of transmission. The notification system is supplemented by screening of pregnant women, military recruits and blood donors, and by surveys of the number of tests performed, and other information. The information is analysed regularly, interpreted and communicated to the health services and the public.

[The HIV-epidemic in Norway 1996--mainly heterosexual transmission]

Up to 1996, a total of 1,537 individuals had been reported as having HIV infection in Norway (population 4.3 million). 511 of these had developed AIDS and 410 had died from AIDS. 223 persons had acquired HIV heterosexually. Less than a fifth of these had acquired the infection from persons who themselves had been infected with HIV heterosexually in Norway. Named testing of pregnant women, recruits and blood donors confirms the limited spread of HIV. We estimate that the annual incidence of heterosexually acquired HIV infection has remained at 20-30 for the last ten years. Earlier prognoses for the epidemic in Norway were grossly erroneous, mainly owing to lack of knowledge about the factors determining the spread of HIV. Given the low rate of transmission of the virus and the sexual behaviour of Norwegians, there was never any real danger of a large heterosexual HIV epidemic in this country. The future efforts to combat the epidemic should focus on maintaining features that make Norwegian society less vulnerable to HIV.

[The HIV-epidemic among homosexual men in Norway]

Up to 1996, 592 men had been reported as having homosexually acquired HIV infection in Norway (population 4.3 million). 295 of these had developed AIDS and 242 had died from AIDS. Although HIV testing is common practice among homosexual men in Norway, we estimate that 100-200 HIV infected homosexual men have not been diagnosed as yet. HIV spread rapidly among homosexuals in Norway in the early 1980s. The annual incidence peaked in 1985, at 70-100 cases, and has since remained at 40-50. In our opinion the initial decrease in incidence was due mainly to dissemination of information by the gay community itself, led by pioneering gay health workers. The stable incidence during the last decade is disappointing, however, considering the vast resources used for prevention. A major challenge in HIV prevention in Norway towards the year 2000 is to bring down the incidence among homosexual men.

[The HIV-epidemic among drug addicts in Norway]

Up to 1996, 368 persons in Norway (population 4.3 million) had been reported as being HIV-infected because of intravenous drug use. 72 of these had developed AIDS and 59 had died from AIDS. HIV-testing is very common among drug users in Norway and new cases are rarely detected at treatment centres or at autopsy. Some 15-30 cases may still be undiagnosed. HIV spread very rapidly among drug users in Norway in 1984 and 1985, by around 100 new cases per year. Since then, the annual incidence has decreased from 30-40 cases in 1986 to 10-15 in 1995. Although the drug users seldom shared syringes even before the advent of the HIV epidemic, we believe that the public rehabilitation programmes, needle exchange programmes and health information have contributed to control HIV in this group. We expect an annual incidence of 10-15 cases the next five years.

[Indications for laboratory testing of gonorrhea. New recommendations from the Working Group against Gonorrhea]

Culture testing for sexually transmitted Neisseria gonorrhoeae infection is widely used in Norwegian general practice. The gain from this testing is very low, since gonorrhoea is almost eradicated in Norway. This reduces the cost-effectiveness of the testing. In cooperation with a panel of medical microbiologists, gynaecologists, venerologists, general practitioners and public health specialists, we have reviewed the literature and drawn up a set of recommendations for the use of culture testing for gonococcal infection to suit the epidemiological situation in Norway. We emphasise clinical testing of men and women, partner notification and tests-of-cure. We do not recommend opportunistic screening for gonococci in any situation whatsoever.

[Infections during the 1995 flood in Ostlandet. Prevention and incidence]

During the 1995 river floods in eastern Norway, 7,000 people were forced to abandon their houses and the public water supplies of some 150,000 people were threatened. The National Institute of Public Health feared outbreaks of waterborne diseases. We supplemented the local preventive efforts with expert advice and public information. We emphasised measures to maintain safe water supplies and to provide information on safe management of flood water during evacuation and clean-up. We observed no increase in the incidence of acute gastroenteritis or other possibly flood-related communicable diseases among the 329,000 people living in the municipalities affected by the floods. We conclude that the floods did not cause a measurable increase in the incidence of communicable diseases. This was probably due to some extent to the measures taken to protect the water supplies.

[Treatment of uncomplicated gonorrhea in adults. New guidelines from the working group against gonorrhea]

Only 229 cases of gonococcal infection were recorded in Norway in 1994 (population 4.3 million), as against more than 14,000 cases two decades before. Up to now aminopenicillins with probenecid have been the standard treatment. In 1994, 29% of the reported cases of gonococcal infection were caused by a betalactamase-producing strain. We now recommend treating uncomplicated gonococcal infections with a single oral dose of ciprofloxacin 500 mg, or ofloxacin 400 mg. Pregnant or lactating women should receive intramuscular injections of cefotaxim 500 mg, or spectinomycin 2 g. Test-of-cure is essential. Its main purpose is to discover resistant strains and reinfections. Thorough contact tracing is more important than ever. Culture verification, susceptibility testing and test-of-cure in all cases will influence the continuous reevaluation of these guidelines.

[May the choice of antibiotics against gonorrhea be guided by anamnesis?]

Aminopenicillin with probenecid is the standard treatment for gonorrhoea in Norway. Nowadays, one fourth of the cases are caused by gonococci that produce betalactamase. Clinicians who have to treat gonorrhoea at the time of first presentation, while awaiting sensitivity testing in the laboratory, are reluctant to use non-standard treatment except when indicated. Is it possible to predict, on the basis of the patient history, which cases need non-standard treatment? A logistic model was fitted to data on a random half of cases of gonorrhoea reported in 1993 and 1994, and validated in the other half of the cases. Infection with betalactamase-producing strains was associated with patients born in Africa or Asia, with patients who had acquired the infection in these areas, and with residence in the Oslo area. Presence of at least one of these factors predicted 87% of the resistant cases, but 54% of patients would have received non-standard treatment. Thus, all patients might as well receive treatment that cures betalactamase-producing strains.

Meningococcal disease in Norway 1992-1995. Epidemiology and fatality

We analysed data on all cases of meningococcal disease (MCD) reported to the Norwegian Notification System for Infectious Diseases during the period 1992-1995. For 1994, additional information on fatalities was gathered. Notifications were received from laboratories and clinicians. A total of 586 patients were included. The incidence decreased from 4.6 per 100000 in 1992 to 2.4 in 1994, and then rose to 3.7 in 1995. The initial decrease, a trend also observed in previous years, was seen in both main serogroups B and C. This decline was broken with the increase of serogroup B in 1995. MCD predominantly affects children below 5 years and teenagers. In 1994, 17/105 (16%) patients died. Main risk factors for fatal outcome were age above 30 years (adjusted odds ratio (OR) 19.8; 95% confidence interval (CI) 2.4-164), septicaemia (adjusted OR 9.5; 95% CI 2.2-41) and disease caused by strains B:15 (adjusted OR 6.4; 95% CI 1.2-35) or C:2a (adjusted OR 10.1; 95% CI 1.6-62). We conclude that the incidence of MCD in Norway is unpredictable and that the case fatality rate is substantially higher than previously believed.

Systemic group B streptococcal disease in neonates and young infants in Norway 1985-94

In the period 1985-94, 237 out of 575,248 (0.41 per 1000) live born infants in Norway were reported to suffer culture-confirmed systemic group B streptococcal disease before their 90th day of life. The annual incidence increased from 0.20 per 1000 live births in 1985 to 0.64 in 1994, due solely to an increase in cases with an onset before the seventh day of life. Future studies should address the possible causes of this increase.

[Use and yield of microbiological diagnosis of sexually transmitted Chlamydia trachomatis infections in Vestfold 1984-93]

Testing for Chlamydia trachomatis has become widely available in Norway during the last ten years. We have evaluated the number and yield of tests in Vestfold county. The number of performed tests increased from 0.6 per 100 inhabitants in 1984 to 6.5 in 1993, while the yield declined from 14.7% to 3.4%. The incidence of diagnosed infection declined from 4.0 per 1,000 person-years in 1988 to 2.2 in 1993. In 1991, 59.6% of the samples were taken from women aged 15 to 29 years. Male patients provided 7.1% of the samples. Between 40 and 50 tests were performed among every 100 Vestfold women in their twenties. More than three quarters of the positive tests were found in women under 25 years of age or in men. Women 30 years of age or older accounted for 32.4% of the tests, but only 9.3% of the positive tests; reaching a yield of less than 1.1%. We recommend that doctors perform fewer screening tests in women older than 25 years and more tests in men following notification by partner. This will increase the yield and reduce the number of false positive tests.

[False positive tests of sexually transmitted Chlamydia trachomatis infections]

We describe the cases of three women who, in 1994, filed complaints of alleged false-positive diagnosis of Chlamydia infection with the Norwegian Patients' Association. They were living in mutually monogamous relationships, but had genital symptoms when they visited their doctor. The positive tests had adverse psychological and social consequences. Two women and their partners had negative repeat tests elsewhere, while one woman found that the laboratory, but not her doctor, had registered her primary test as negative. We suggest measures to reduce the number of false-positive tests and to prevent adverse psychological and social consequences of such tests. Patients should be involved in the decision to perform a Chlamydia test. The doctors should be aware of the possibility of false results, and must improve their information to patients with positive tests.

[Indications for testing for sexually transmitted Chlamydia trachomatis infections]

Laboratory testing for sexually transmitted Chlamydia trachomatis infection is widely used in Norwegian general practice. The yield of this testing is declining, since the prevalence of infection in the community has decreased. Thus, the cost-effectiveness of testing is reduced, and the risk of false positive results using non-culture methods has increased. In cooperation with a panel of medical microbiologists, gynaecologists, venerologists, general practitioners and public health specialists, we have reviewed the literature and drawn up a set of recommendations for the use of laboratory testing for genital C. trachomatis infection. We emphasize clinical testing of men and women, notification of partners in order to reach males, and screening of women under the age of 25 after each change of sexual partner.

[Evaluation of the National Notification System for infectious diseases during an outbreak of Shigella epidemic in Norway 1994]

The National Notification System for Infectious Diseases, in Norwegian abbreviated to MSIS, registered 110 cases of Shigella sonnei-infection in persons with debut of symptoms during weeks 21 to 25, 1994, and where we did not receive information that the patients had been abroad. We evaluated the notification system during this outbreak of infectious disease by looking at delays in the notification process and estimating the proportion of patients who received an etiological diagnosis. It took a median time of seven days from onset of illness until a faecal specimen was obtained and a further ten days (maximum 15 days) until the result was registered in MSIS. The time lapse between receiving the specimen until MSIS had registered the result varied from six to 15 days among the laboratories which sent more than four notifications. In the summarical notification system we registered an increase of 712 cases (86%) of acute gastroenteritis compared with the same week the previous two years.

[High incidence and mortality of systemic pneumococcal disease among persons without spleen]

We surveyed 472 cases of culture-confirmed systemic pneumococcal disease that were reported to the Norwegian Notification System for Infectious Diseases during a 12-month period in 1992-93. The clinicians in charge of the patients filled in a questionnaire providing information on underlying disease and outcome for 461 (98%) of the patients. Eight of these patients were splenectomized; all of them more than ten years before. Four died, two survived but had serious sequelae, and two survived without obvious sequelae upon discharge from hospital. Using a rough estimate of the prevalence of unvaccinated splenectomized persons in Norway, we estimate that this group, compared to the normal population, has a relative risk of 25 of developing systemic pneumococcal disease and a relative risk of 75 of dying from pneumococcal disease. The serotype of the pneumococcal strain that caused the disease was determined for seven of the eight patients. All serotypes were represented in the 23-valent pneumococcal polysaccharide vaccine. We strongly recommend that doctors trace and vaccinate splenectomized individuals.

Use of laboratory testing for genital chlamydial infection in Norway

OBJECTIVE

To assess the use of laboratory tests for genital chlamydial infection in Norway.

DESIGN

Questionnaire survey of general practitioners' practice in chlamydial testing, retrospective survey of laboratory records, 1986-91, and prospective study of testing in one laboratory during four weeks.

SETTING

All 18 microbiological laboratories in Norway (4.2 million population), including one serving all doctors in Vestfold county (0.2 million population).

SUBJECTS

302 general practitioners.

MAIN MEASURES

GPs' routine practice, methods used for testing, 1986-91, and sex specific and age group specific testing in 1991.

RESULTS

201(69%) GPs replied to the questionnaire: 101(51%) would test all women younger than 25 years at routine pelvic examination, 107(54%) all girls at first pelvic examination, 131(66%) all pregnant women, and 106(54%) all men whose female partner had urogenital complaints. Nationwide in 1986, 122,000 tests were performed (2.9 per 100 population); 10% were positive and 51% were cell culture tests. In 1991, 341,000 tests were performed (8.0 per 100 population); 4.5% were positive and 15% were cell culture tests. 13,184 tests were performed in Vestfold in 1991 (6.6 per 100 population). The age group specific rates (per 100 population) among women were: age 15-19 years, 22.0(95% confidence interval 18.2 to 25.8); 20-24 years, 47.2(42.1 to 52.3); 25-29 years, 42.3(37.1 to 47.5); 30-34 years, 29.8(25.4 to 34.2); and 35-39 years, 12.5(9.5 to 15.5).

CONCLUSIONS

GPs use liberal indications for testing. The dramatic increase in testing, especially by enzyme immunoassays, in populations with a low prevalence of infection results in low cost effectiveness and low predictive value of positive tests, which in women over 29 years is estimated as 17-36%.

IMPLICATIONS

Doctors should be educated about the limitations of enzyme immunoassays in screening low prevalence populations, and laboratories should apply a confirmatory test to specimens testing positive with such assays.

[Follow-up after treatment of genital chlamydia infection]

We surveyed routine practice among a random sample of 302 Norwegian general practitioners. 49% perform a test of cure in all the patients whom they treat for genital infection caused by Chlamydia trachomatis. 22% of the practitioners test "most" patients, 19% test "some" patients while 10% of the general practitioners test none of the patients after treatment for genital chlamydial infection. Female practitioners perform more tests of cure than male practitioners do. Most tests are performed 1-4 weeks after completion of treatment. Although test of cure has been a controversial topic, we believe it to be a useful measure against the epidemic of genital chlamydial infections. The purposes of the test are to establish whether or not the treatment has been effective and ensure that the patient has not been reinfected by a partner who did not receive treatment. The test of cure must be performed later than two weeks after completion of treatment, in order to avoid false positive tests as a result of residual chlamydial antigen in the genitalia.

[Prevalence of hospital infections in Norwegian somatic hospitals]

A nation-wide survey of the prevalence of hospital-acquired infections was carried out on 25 April 1991. The purpose of the study was to assess the size of the problem, to find out in which medical disciplines they occur and what types of infections dominate, and to motivate hospital personnel for training in infection control. The survey included 77 somatic hospitals with a total of 15,160 patients. 4,418 patients had undergone surgery during their stay in hospital. 1,063 were newborns. On the day of the survey 976 clinically manifest infections were recorded. This gave a total prevalence rate of 6.4%. At county level the prevalence rates varied from 3.8 to 8.9%. The prevalence rate for surgical wound infections was 3.7%. Urinary tract infections accounted for 33.6% of the total infections, followed by lower respiratory tract infections (16.8%), and surgical wound infections (16.6%). The study indicates in which medical disciplines the problems of infection are most serious, and where the control should be strengthened. It also provides a good basis for further detailed studies of hospital-acquired infections.

Survey of the treatment of Chlamydia trachomatis infection of the female genital tract

A questionnaire was sent to every tenth (n = 302) general practitioner in Norway. The physicians were to indicate their choice of antibiotic regimen for the treatment of genital chlamydial infections in women. Sixty-nine percent of the practitioners responded. The choice of treatment varied widely between the respondents. Forty-two different regimens were used for chlamydial cervicitis, 34 for cervicitis in pregnancy and 63 for probable pelvic infection. Of the prescribed treatments for these three diagnoses 14%, 5% and 46%, respectively, were compatible with the advice of the World Health Organization or the Centers for Disease Control. For the three previously mentioned diagnoses 49%, 79% and 43%, respectively, of the practioners would prescribe an antibiotic in either smaller doses, fewer daily doses or shorter duration than recommended. There is an urgent need to improve and standardize Norwegian general practitioners' treatment of chlamydial infection in women.

[Contact tracing in genital chlamydia infections]

Only one in five general practitioners in Norway initiates notification of partner(s) after diagnosing a case of genital chlamydial infection. In order to increase the use of this efficient case-finding method we review the aims of notifying partners and the judicial, ethical and economical aspects of the method. We describe both provider-referral and patient-referral methods. The first approach is chosen when the index patient wants to remain anonymous. General practitioners are advised not to give the index patient medication for the contacts. Instead, the contacts should be examined and informed by qualified personnel. Notification of partner will be a cornerstone in the struggle to control the current epidemic of genital chlamydial infection in Norway.

[Contact tracing routines for genital chlamydia infections used by Norwegian physicians. A questionnaire study]

Notification of partner(s) is recommended as a measure to control the epidemic of genital chlamydial infection. We surveyed a random sample of Norwegian general practitioners and privately practising gynaecologists. Only one in five general practitioners initiated notification of partner(s) after diagnosing a patient with genital chlamydial infection. A proposed new Communicable Diseases Act will make it mandatory to notify the partner in the event of such infections. 49% of general practitioners are in favour of the proposal, 21% oppose it while 30% remain uncertain. After implementation of similar legislation, Sweden has experienced a decline in the incidence of genital chlamydial infection. We believe increased notification of partner would help to control the Norwegian epidemic.

Hospital-acquired infections in Norway: a national prevalence survey in 1991

A 1-day prevalence survey of hospital-acquired infections (HAI) was carried out in Norwegian somatic hospitals in 1991. The survey aimed at assessing the problem of HAI. 950 infections were found among the 14977 surveyed patients (prevalence rate 6.3%). HAI were more prevalent in combined intensive care units (prevalence rate 22%), surgical intensive care units (17%), haematological wards (15%), special care baby units (14%), and geriatric wards (14%). Urinary tract infections were most prevalent (33% of all HAI) followed by respiratory tract infections (21%) and surgical wound infections (17%). 157 (3.6%) of the 4382 patients who had undergone surgery, had a surgical wound infection. With a high response rate (76 out of 84 hospitals) and a sensitive method of screening the patients (chart review and bedside examination), this survey gives a fairly reliable measure of the prevalence of HAI in Norwegian somatic hospitals.