Use of highly active antiretroviral therapy is associated with lower prevalence of anal intraepithelial neoplastic lesions and lower prevalence of human papillomavirus in HIV-infected men who have sex with men.

BACKGROUND: The incidence of anal intraepithelial neoplasia (AIN) and anal cancer is increased in HIV-positive men who have sex with men (MSM). Persistent high-risk human papillomavirus (HPV) infection is an important etiologic agent. METHODS: In this study, a group of 250 HIV-positive MSM was included to determine the prevalence of AIN and to investigate the role of highly active antiretroviral therapy (HAART), high-risk HPV, and other risk factors possibly associated with this prevalence. RESULTS: Among patients included, 108 (43.2%) had lesions suspicious for AIN. Histologic analyses showed AIN 1 in 24 patients (22.2%), AIN 2 in 6 patients (5.6%), and AIN 3 in 10 patients (9.3%). In multivariable analyses, the use of HAART was associated with the absence of AIN (P = 0.045). In MSM without HAART, HPV infection was detected significantly more often compared with those who used HAART (P = 0.010). AIN was associated with HPV types 16 and 6. CONCLUSIONS: In this cross-sectional study in 250 HIV-positive MSM, the use of HAART was associated with lower prevalence of AIN and a significantly lower prevalence of HPV. This association between the prevalence of AIN and the absence of HAART may contribute to the current debate on when to start HAART in HIV-infected individuals.

Quantification of viral DNA and liver enzymes in plasma improves early diagnosis and management of herpes simplex virus hepatitis.

Herpes simplex virus (HSV) hepatitis is a rare and potential life-threatening disease. The diagnosis of HSV hepatitis is hampered by its indifferent clinical presentation, which necessitates confirmatory laboratory data to identify HSV in the affected liver. However, liver biopsies are often contraindicated in the context of coagulopathy, are prone to sampling errors and have low sensitivity in mild HSV hepatitis cases. There is an unmet need for less invasive diagnostic tools. The diagnostic and therapeutic value of HSV DNA load and liver enzyme level kinetics was determined in five patients with HSV hepatitis and twenty disease controls with HSV-DNAemia without hepatitis. At time of hospitalization, patients with HSV hepatitis had a higher median (± interquartile range) HSV DNA load (6.0 × 10(6) ± 1.2 × 10(9)) compared to disease controls (171 ± 2845). Viral DNA load correlated with liver transaminase levels and disease severity. Antiviral treatment led to rapid decline of HSV DNA load and improvement of liver function of patients with HSV hepatitis. The data advocate the prompt and consecutive quantification of the HSV DNA load and liver enzyme levels in plasma of patients suspected of HSV hepatitis as well as those under antiviral treatment.

Norovirus in a Dutch tertiary care hospital (2002-2007): frequent nosocomial transmission and dominance of GIIb strains in young children.

We report a retrospective analysis of norovirus (NoV) infections occurring in patients of a tertiary care hospital during five winter seasons (2002/03 to 2006/07). Data were compared with national surveillance data and with corresponding data for rotavirus. Between July 2002 and June 2007, faecal specimens from 221 (9.0%) of 2458 hospital patients with diarrhoea tested positive for NoV. The incidence in children varied from 2.52 per 1000 admissions in 2004/05 (when testing began to be performed routinely) to 11.9 per 1000 admissions in 2006/07, while the incidence in adults remained stable (mean: 1.49 per 1000 admissions). Two genotypes predominated during the study period: GIIb strains occurred mainly in children below the age of two-and-a-half years [odds ratio (OR): 14.7; P<0.0001] whereas GII.4 strains affected all age groups. Compared with rotavirus infections, NoV infections in children were more often hospital-acquired (59% vs 39%, OR: 2.29; P<0.01). Among these cases we identified 22 clusters of NoV infection among inpatients. Twelve of 53 patients from whom follow-up samples were available demonstrated long-term virus shedding. We report a dynamic pattern of sporadic NoV infections in large hospitals, with frequent nosocomial transmission and with the predominance of GIIb-related strains in children. Effective prevention strategies are required to reduce the impact of sporadic NoV infection in vulnerable patients.

A cluster of hepatitis B infections associated with incorrect use of a capillary blood sampling device in a nursing home in the Netherlands, 2007.

In July 2007, two residents of a nursing home were diagnosed with acute Hepatitis B virus infection. To identify risk factors for HBV infection a retrospective cohort study among residents was performed. Case finding included discharged diabetes patients and those receiving home care. Among 32 residents one case of chronic hepatitis B was found that could be identified by genotyping as the source patient for the acute cases. Diabetes and finger sticks were risk factors for HBV infection. Most likely the cause of transmission was a multiclix finger stick device developed for use in individual patients but used in multiple patients. Education and training in the use of new equipment and hygiene audits remain the cornerstones in infection control practices.

[First case of chikungunya diagnosed in the Netherlands]. / Chikungunya voor het eerst gediagnosticeerd in Nederland.

A 52-year-old man was seen in the Diagnostic Centre for Tropical Diseases of the Havenziekenhuis, Rotterdam, presenting with arthralgia, fever and exanthema following a stay in Mauritius. Infection with the Dengue virus infection is a common diagnosis for this combination of complaints, but nowadays chikungunya should also be considered. This is particularly the case when a patient has visited a country in or around the Indian Ocean. Risk areas are La Réunion and Mauritius, where, in February 2005 and April 2005 respectively, epidemics broke out. Chikungunya is a viral infection. The causative virus is an Alpha virus, transmitted by mosquitoes. The symptoms include arthralgia, myalgia, diffuse maculopapular rash, fever and headache. In contrast to dengue, chikungunya is not associated with haemorrhagic diathesis. Treatment takes place in response to the symptoms, since there is no targeted therapy available. The main preventive measure is to prevent mosquito bites. The disease is not deadly and healing is spontaneous. To our knowledge this is the first case of chikungunya diagnosed in the Netherlands during this epidemic. The disease has recently been reported in Italy, where native mosquitoes transmit it.

[Hepatitis B virus transmission patterns in the Netherlands, 2004]. / Transmissiepatronen van hepatitis B-virus in Nederland, 2004.

OBJECTIVE: To gain insight into hepatitis B virus (HBV) transmission in the Netherlands. DESIGN: Descriptive. METHOD: During 2004, epidemiological data and blood samples (if available) were collected for all reported cases of acute HBV infections in the Netherlands. Following DNA isolation and amplification a 648 base pairs fragment of the HBV S gene was sequenced and subjected to phylogenetic analysis. The sequencing details were also linked to epidemiological information. RESULTS: In 2004, 291 cases ofacute HBV infections were reported. Blood samples were received from 171 patients (59%), and the genotype could be determined for 158 patients (54%). 6 genotypes were identified: A (64%), B (3%), C (3%), D (21%), E (5%) and F (4%). Of all patients with genotype A, 52% had been infected via homosexual or bisexual contact and 16% via heterosexual contact. Of all patients with genotype D, 42% had been infected via heterosexual contact and 15% via homosexual or bisexual contact. The genotype A cluster was extremely homogeneous with many identical sequences, while genotype B-E clusters were more heterogeneous. 4 identical sequences were found within genotype F, but the patients could not be epidemiologically linked. CONCLUSION: Sexual transmission, particularly via homosexual or bisexual contact in men, formed the most important risk factor for acquiring an acute HBV infection. Genotype A was predominant in the Netherlands, especially among homosexual or bisexual men. Most infections within genotype D occurred as a result of heterosexual contact. The results show that there was ongoing transmission of HBV in homosexual or bisexual men, while in heterosexuals more cases of new introduction were seen, possibly via chronic carriers from areas where HBV is endemic.

Haemorrhagic Fever with Renal Syndrome: an analysis of the outbreaks in Belgium, France, Germany, the Netherlands and Luxembourg in 2005.

This article aims to describe the Haemorrhagic Fever with Renal Syndrome (HFRS) situation in 2005 in five neighbouring countries (Belgium, France, Germany, the Netherlands and Luxembourg) and define the most affected areas. The 2005 HFRS outbreaks in these countries were the most significant in the region since 1990, with a total of 1,114 confirmed cases. The main feature of the epidemic was the extension of the known endemic area in several of the affected countries, with the involvement of urban areas for the first time. A significant increase in the number of cases was noted for the first time in the province of Liège in Belgium and in the Jura department in France.

Public health implications of using various case definitions in The Netherlands during the worldwide SARS outbreak.

This study analysed the consequences of deviation from the WHO case definition for the assessment of patients with suspected severe acute respiratory syndrome (SARS) in The Netherlands during 2003. Between 17 March and 7 July 2003, as a result of dilemmas in balancing sensitivity and specificity, five different case definitions were used. The patients referred for SARS assessment were analysed from a public health perspective. None of the patients referred had SARS, based on serological and virological criteria. Nevertheless, all 72 patients required thorough assessment and, depending on the results of the assessment, institution of appropriate prevention and control measures. Changing case definitions caused confusion in classifying cases. A centralised assessment of the reported cases by a team with clinical and public health expertise (epidemiological and geographical risk assessment) is a practical solution for addressing differences in applying case definitions. The burden of managing non-cases is an important issue when allocating public health resources, and should be taken into account during the preparation phase, rather than during an outbreak. This applies not only to SARS, but also to other public health threats, such as pandemic influenza or a bioterrorist episode.

Successful vaccination against varicella zoster virus prior to kidney transplantation.

BACKGROUND: In recent years we have observed a number of severe complications of primary varicella-zoster virus (VZV) infections after adult kidney transplantation. We questioned how many patients on the waiting list for kidney transplantation had not been protected against VZV and whether patients with renal insufficiency would be able to develop a specific immune response upon VZV vaccination. METHODS: We examined the VZV antibody titer of 280 patients on the kidney transplant waiting list. Seronegative kidney transplant candidates were vaccinated twice with a live attenuated varicella vaccine at an interval of 6 weeks. CONCLUSIONS: Approximately 3% of patients on the waiting list were seronegative for VZV. Vaccination induced no side effects and resulted in a positive serologic response in most patients.

Heterosexuals at risk for HIV: differences between private and commercial partners in sexual behaviour and condom use.

To study the prevalence of HIV and other sexually transmitted diseases (STDs), sexual behaviour and condom use among heterosexuals, 193 women and 157 men entered a longitudinal study. Participants were recruited through an STD clinic, and had had five or more heterosexual partners in the preceding 6 months but had no other AIDS risk factors. Participants were divided in groups with respect to private and/or commercial sexual partners. One hundred and thirty-six (71%) women worked as prostitutes and had, on average, 115 customers a month, and 99 (63%) men had visited, on the average, eight prostitutes in the past 4 months. One hundred and seventy-one (89%) women (114 prostitutes) had had, on average, four partners, and 112 (78%) men (of whom 64 had visited prostitutes) had had, on average, seven private partners in the past 4 months. Vaginal intercourse was often or always reported by all participants whilst anal contact was seldom reported. Non-high-risk sexual techniques (for example, oro-oral, masturbation) were practised more frequently with private than with commercial partners (P less than 0.001). Although no differences were found in the frequency of practising high-risk sexual techniques (for example, vaginal, ano-genital), differences were found for frequency of condom use. Condom use during vaginal intercourse was reported more frequently with commercial than with private partners (P less than 0.01). However, if the number of partners is taken into account, prostitutes had unprotected vaginal intercourse with an estimated average number of 160 partners in 4 months, which is far more than customers (seven) and men and women with private partners only (four).(ABSTRACT TRUNCATED AT 250 WORDS)

HIV surveillance among sexually transmitted disease clinic attenders in Amsterdam, 1991-1996.

OBJECTIVE: To determine trends in HIV prevalence among attenders of a clinic for sexually transmitted diseases (STD), with emphasis on heterosexuals who did not have a history of injecting drug use. METHODS: Anonymous unlinked HIV surveys with individual consent, conducted each half year from 1991 to 1996 (except 1993) among STD clinic attenders who came for evaluation of a possible new STD episode. RESULTS: Of 10,940 eligible attenders 10,046 (92%) accepted HIV testing. Of all tested attenders, 312 (3.1%) were HIV-infected. Overall HIV prevalence decreased significantly from 4.6% in 1991 to 2.8% in 1996. HIV prevalence among heterosexual men and women who were not injecting drug users was less than 1% in all but one survey period. Except for one woman, none of the 48 HIV-infected heterosexuals was aware of their current serostatus. Among HIV-infected heterosexuals, 21 out of 28 males (75%) and 18 out of 20 females (90%) were of non-Dutch origin. HIV prevalence was 16% among all homosexual men, and 12% among young homosexual men aged < 30 years. HIV prevalence among young homosexual men decreased significantly over time. Among HIV-infected homosexual men, 58% of older men and 59% of younger men were not aware of their current HIV infection. Rates of current STD were generally significantly higher among HIV-infected participants compared with non-HIV-infected participants. CONCLUSIONS: Although HIV prevalence among heterosexual clinic attenders is low, there is a clear potential for ongoing sexual HIV transmission. Most heterosexually acquired HIV infections are found in non-Dutch persons. This observation suggests migration of HIV-infected heterosexuals or the separation of Dutch and non-Dutch heterosexual networks. Awareness of serostatus is almost non-existent among HIV-infected heterosexuals, and is low among male homosexual clinic attenders. To increase awareness of current HIV serostatus and possibly decrease risk behaviour, HIV counselling and testing should be offered actively to all clinic attenders.

The impact of immigration on env HIV-1 subtype distribution among heterosexuals in the Netherlands: influx of subtype B and non-B strains.

OBJECTIVE: To examine the epidemiological factors influencing the distribution and spread of HIV-1 subtypes among heterosexuals in the Netherlands. METHOD: A nationwide serosurveillance in 21 HIV/AIDS centres from 1997 to 1999 involved 200 individuals for whom the mode of HIV transmission was heterosexual contact or unknown. HIV-1 subtypes were determined by phylogenetic analysis of env V3 sequences and correlated with sociodemographic characteristics of the subjects and their sexual partners. RESULTS: HIV-1 subtype B infection occurred in 121 subjects (60%). Non-B subtypes were identified in 31 (A), 24 (C), 10 (D), six (E), four (F) and three (G) individuals; one had an unclassified subtype. The proportion of subtype B was about 60% in four of the six regions of the Netherlands, but in the Northwest and Southwest regions these proportions were 76% and 46%, respectively. The Surinamese and Antilleans, large immigrant groups, were all infected with subtype B, as were almost all individuals with an unknown source. The proportions of non-B viruses did not change significantly over time in Amsterdam, where subtyping was available from 1988 onward, but a shift in the various subtype B strains was observed, suggesting introductions of new subtype B strains in Amsterdam. CONCLUSION: To date, HIV-1 non-B subtypes in the Netherlands are still found predominantly among heterosexuals with an epidemiological link with sub-Saharan Africa. Despite continuing introductions of non-B subtypes, the B/non-B distribution has been stable over time, most likely as a result of introductions of subtype B strains from Caribbean and South American countries.

Prevalence and correlates of herpes simplex virus type 2 infection: evaluation of behavioural risk factors.

OBJECTIVE: To examine the prevalence and correlates of infection with herpes simplex virus type 2 (HSV-2) among sexually transmitted disease (STD) clinic attenders, we studied the prevalence of antibodies to HSV-2 and their association with risk behaviour. METHODS: Data were collected in a cross-sectional study among STD clinic attenders in Amsterdam. Seropositivity for HSV-2 was determined in 1798 serum samples by means of a monoclonal antibody-blocking enzyme-linked immunoassay. RESULTS: The prevalence of HSV-2 antibodies was higher than expected: 32.3% in a population in which 3% had current genital herpes and 8% gave a history of genital herpes. Of those with HSV-2 antibodies, only 18% had a history of genital herpes. A strong independent association with the presence of HSV-2 antibodies was found for sexual behaviour, more specifically: homosexual orientation, increasing number of years of sexual activity, increasing number of lifetime partners, number of past gonococcal infections, having receptive anal and (or) vaginal contact. CONCLUSION: The presence of HSV-2 antibodies had a strong association with past sexual behaviour and, for both sexes, with receptive anal intercourse. HSV-2 antibodies may be used as a surrogate marker of sexual risk behaviour in comparing different populations over time.

[Evaluation of the hepatitis B prevention program in newborn infants. II. Amsterdam, 1989-1991]. / Evaluatie van het hepatitis B-preventieprogramma bij pasgeborenen. II. Amsterdam, 1989-1991.

OBJECTIVE: To evaluate the efficiency of the hepatitis B surface antigen (HBsAg) screening programme in pregnant women and the hepatitis B prevention programme in neonates of HBsAg-positive mothers from October 1989 to December 1991. DESIGN: Retrospective. SETTING: Amsterdam Public Health Service, the Netherlands. METHOD: Analysis of the data routinely collected from pregnant women and neonates of these women and calculation of the protective efficiency of this immunisation programme. RESULTS: In 1990, 79% and in 1991, 91% of all pregnant women were screened for HBsAg. The overall prevalence was 1.2% in 1990 as in 1991. Of the HBsAg-positive women 96% originated from countries where hepatitis B virus (HBV) is known to be endemic. At the age of ten months all infants had received passive and active immunisation. The anti-HBs titre was 10-50 IU/l in 8 (7%) infants, > 50 IU/l in 94 (88%), 3 were HBsAg-negative with no information on the anti-HBs titre and in 2 HBsAg was present. The protective efficiency of the immunisation schedule was 94% in children born of e-antigen-positive and 93% in children born of e-antigen-negative mothers. CONCLUSION: Active surveillance and intense follow-up are essential in achieving high coverage rates in screening of pregnant women and in immunising neonates of HBsAg-positive mothers.

[Accidental exposure to blood and the risk of transmission of virus infections for various occupational groups in Amsterdam, 1986-1996]. / Accidentele blootstelling aan bloed en risico op transmissie van virusinfecties bij verschillende beroepsgroepen in Amsterdam, 1986-1996.

Since 1986 the number of parenteral exposures to potentially infectious blood reported to the Amsterdam Public Health Service increases every year. The number of needlestick accidents increased significantly from 64 in 1986 to 166 in 1996 whereas the number of other exposures decreased from 59 to 44 in these years. The increase was mainly seen in nonhospital based (para)medics. A possible explanation of this increase is greater awareness of the potential infection risk with HIV, hepatitis B or C virus leading to a tendency to report more readily. This assumption is in contradiction with results of studies in hospital-based personnel where a decrease is observed as a result of educational programmes. Other explanations are a higher frequency of use of sharp instruments and (or) an increase in the workload. Out of a total of 1886 needlestick accidents in 1986-1996 one woman became HIV positive; she was deliberately infected by her ex-partner who injected her with blood of an AIDS patient, and one person contracted an hepatitis C virus infection: a policeman wounded by a needle used by a drug addict.

[Positive results from serologic screening for syphilis in pregnancy in the Amsterdam region, 1991-1995]. / Het nuttig effect van serologische screening op syfilis in de zwangerschap in de regio Amsterdam, 1991-1995.

OBJECTIVE: To evaluate the results of screening of pregnant women for syphilis in the region of Amsterdam, the Netherlands. DESIGN: Descriptive study and cost-benefit analysis. METHODS: In the period 1991-1995, physicians and midwives from the Amsterdam region sent serum samples of pregnant women to the Regional Public Health Laboratory of the Municipal Health Service (GG & GD) to be screened for syphilis. All physicians who had sent in specimens with a positive result of the Treponema pallidum haemagglutination assay (TPHA) and a confirming test result were asked, in the year of the screening, by telephone or in writing, what diagnosis they had made in the woman in question. Collection of these data was handled by the social nursing staffs of the outpatient clinics for sexually transmitted diseases in Amsterdam. The costs of laboratory tests and follow-up of the children were compared with the positive effects of special treatment and education avoided by antibiotic treatment. RESULTS: 54,344 serum samples were sent in. In the city of Amsterdam the coverage was 87.4%. In 81 women (0.15%) all the serological tests for syphilis were positive. From this group, 37 women had already been treated and 24 women were treated as a result of this screening programme (most of them had a foreign nationality), 10 for early syphilis and 14 for syphilis of unknown duration, preventing the birth of an estimated five to six children with congenital syphilis. The cost-benefit ratio was 1:15. CONCLUSION: Continuation of screening for syphilis during pregnancy in the Amsterdam region remains useful.

[Analysis of antibodies against human immunodeficiency virus on a voluntary basis in healthy persons in Amsterdam 1988 and 1989]. / Onderzoek op antistoffen tegen humaan immunodeficiëntievirus op vrijwillige basis bij gezonde personen te Amsterdam in 1988 en 1989.

At the Municipal Health Service of Amsterdam it is possible to be tested for HIV antibodies after signing an informed consent. In 1988, 1247 persons were tested (797 men, 450 women) and in 1989, 1400 persons (869 men, 531 women). Fifty-eight persons were identified as HIV-seropositive for the first time (1988: 24 men, 3 women; 1989: 28 men, 3 women). All but one woman belonged to a risk group or had had sexual contact with a person from a known risk group. In 1989 no increase in the percentage of HIV-seropositive persons was seen. In our (selected) group of persons in 1988 and 1989 we saw no transmission of HIV outside the known risk groups.

[HIV surveillance in an outpatient clinic for sexually transmissible diseases in Amsterdam, 1991-1994; low and stable prevalence among heterosexual clients]. / HIV-surveillance op een polikliniek voor seksueel overdraagbare aandoeningen in Amsterdam, 1991-1994; lage en stabiele prevalentie onder heteroseksuele bezoekers.

OBJECTIVE: To assess the HIV prevalence among heterosexual attenders of a clinic for sexually transmitted diseases (STD) and among subpopulations, including young gay men and ethnic minorities. SETTING: Outpatient clinic for sexually transmitted diseases (STD) of the Municipal Health Service of Amsterdam, the Netherlands. METHODS: Semi-annually in the period 1991-1994, blood samples given voluntarily and anonymously were tested for HIV antibodies and some characteristics were collected of approximately 1000 clinic attenders. RESULTS: Since 1991, 6766 clinic attenders were eligible for participation, of whom 6200 (92%) were actually tested. The overall HIV prevalence decreased from 3.9% in the first half of 1991 to 2.3% in the second half of 1994. Among heterosexual clinic attenders the prevalence remained stable below 1%, due mainly to visitors from abroad rather than to Dutch heterosexuals: 20 of the 23 HIV infected heterosexuals were not Dutch. None of these 23 seropositive persons knew of their HIV infection, mostly because they had not been tested previously. The HIV prevalence among gay men decreased over the years. In addition, the number of gay male attenders younger than 30 years decreased strongly over time. CONCLUSIONS: HIV infections among heterosexual STD clinic attenders are relatively few and are seen mainly among non-Dutch. We found no indications of an increase of the HIV prevalence among heterosexual clinic attenders. The results among young gay men are suggestive of a shift towards safer sexual behaviour in this group.

[Prevalence and risk factors of Chlamydia trachomatis infection in clients of a venereal disease clinic in Amsterdam]. / Vóórkomen en risicofactoren van infectie met Chlamydia trachomatis bij bezoekers van een geslachtsziektenpolikliniek in Amsterdam.

We studied the prevalence of Chlamydia trachomatis (CT) infection as well as its predictors among a sample (1000) of visitors (651 male, 349 female) of a clinic for sexually transmitted diseases (STD) in Amsterdam. The prevalence of CT was higher than that of gonorrhoea: among men, 14.3% and 11.5% and among women, 12.9% and 6.3% respectively. Independent predictors for CT infections were for men: number of leucocytes in discharge or urine, nature of urethral discharge, age and sex behavior, and in women: being warned as source or contact of a STD, age, nature of cervical discharge and bleeding from the cervical ostium after insertion of a swab. As many as 92% of the male and 81% of the female visitors of our STD clinic should be examined for CT if the presence of anyone or more of these predictors is taken as a criterion. Even then, 5% of the CT infections in women would still be missed. Based on our study results, material for the diagnosis of CT will from now on be collected routinely from all female patients of our STD clinic as well as from all males with urethritis. We advocate the expansion in the Netherlands of facilities for laboratory CT detection and its standard inclusion in STD examination.