Immunity to hepatitis A when outbreaks of infection in men who have sex with men (MSM) are rare. Vaccine. 2012;30:3430-3434. [PMID: 22449421 DOI: 10.1016/j.vaccine.2012.03.024]

A description of a hepatitis A outbreak in men who have sex with men and public health measures implemented in Seine-Maritime department, Normandy, France, 2017

BACKGROUND

In 2016-2017, a European-wide circulation of genotype IA hepatitis A virus was responsible for hepatitis A outbreaks in men who have sex with men (MSM). This study aimed to describe the outbreak investigation in Seine-Maritime department (France) and the control measures implemented accordingly.

METHODS

Outbreak description used data from mandatory reporting and enhanced surveillance of male cases. Confirmed case was genotype IA isolated, possible cases had no reported genotype information. Targeted control measures included communication on sexual practices at risk of hepatitis A transmission and two vaccination campaigns in April 2017 and January 2018. Characteristics of cases and vaccinees were described. We reported the best communication channel for relaying outbreak information and control measures based on the monitoring of social network activities and feedback from vaccinees.

RESULTS

During the outbreak period (December 2016 to December 2017), a total of 48 confirmed outbreak cases and 30 possible outbreak cases were notified. Among them, 69 were male (88%). Two epidemic waves were observed. Cases encountered their partners through gay-dating apps (54%) and in one specific sauna (62%). In response to the outbreak, two vaccination campaigns were deployed. A total of 156 MSM were vaccinated, of whom 56 in a truck parked beside the sauna. Most of the vaccinees had been informed about the campaign through dating apps (44%). Community-based organizations involved in sexual health promotion and other gay social media were very proactive in sharing information about the outbreak and promoting the vaccination campaign through their social media account and also on site (gay venues). Vaccinees reported the same sexual practices at risk of hepatitis A transmission as cases.

CONCLUSIONS

In response to this massive hepatitis A outbreak that affected mostly MSM in Seine-Maritime department, vaccination campaign remained the cornerstone of prevention. Prevention officers from the community-based organization played a key role in vaccination promotion. Gay-dating apps and outdoor sessions of vaccination allowed to effectively reach MSM. Cost-effectiveness studies might analyze the interest of a continuous sexual health promotion including vaccination against hepatitis A in MSM through dating apps and social networks.

Sexual behaviour and poor hygiene are related to recent hepatitis a virus community outbreaks

OBJECTIVES

there has been a global increase in the incidence of hepatitis A infection. The aim of this study was to examine the characteristics of the increase in our region and the degree of adherence to the recommended hygienic measures after discharge from hospital.

METHODS

demographic, clinical and biochemical variables were collected from patients with acute hepatitis A in our health area. The patients were grouped as follows: January 2010 to December 2016 (historical cohort) and January 2017 to October 2017 (recent cohort). A phylogenetic analysis was also performed in the recent cohort. One month after discharge, bacterial growth was evaluated by a culture of the dominant hand imprint and were compared with a control group.

RESULTS

a total of 110 cases were registered with a median age of 36.3 years (range 3-89) and 77.3 % were male. The incidence was 0.82/100,000 inhabitants/year and 22.75/100,000 inhabitants/year in the historical and recent cohorts, respectively. Patients in the recent cohort were more frequently male (52.6 % vs. 82.4 %, p = 0.008) and younger (51.7 [3-89] vs. 33.4 [4-74] years, p < 0.001). In addition, 63.8 % of the recent cohort were men who had sex with other men and had unsafe sexual practices (37.5 %). Phylogenetic analysis showed a predominance of genotype A and a high frequency of the VRD 521-2016 sequence. A higher growth of enterobacteria was observed in patients with hepatitis A compared to the control group (7.3 % vs. 1.2 %, p = 0.005), despite specific hygienic measures given at discharge.

CONCLUSIONS

a recent outbreak of hepatitis A in our area was related with gender, younger age and sexual practices. Hepatitis A infected subjects showed a poor adherence to hygienic measures. Our data suggests the need for policies that encourage preventive actions, particularly vaccination in this high-risk group.

Immunity to hepatitis A among men who have sex with men attending a large sexual health clinic in Melbourne, Australia, 2012-2018

BACKGROUND

Outbreaks of hepatitis A are being reported more commonly among men who have sex with men (MSM) globally. Australia has also reported a sharp increase in the number of cases of hepatitis A in 2017. This study aimed to determine the level of immunity to hepatitis A among MSM attending a large urban sexual health clinic in Victoria in the lead up to recent outbreak.

METHODS

This was a retrospective audit of serological testing data from first-time MSM attendees at Melbourne Sexual Health Centre (MSHC) in Australia from 1 January 2012 to 31 December 2018. We determined the proportion of MSM who were tested and who had serological detection of hepatitis A IgG, stratified by age and calendar year. We used univariable and multivariable logistic regression to investigate factors associated with testing for and detection of hepatitis A IgG.

RESULTS

There were 16 609 first-time MSM attendees at MSHC over the 7-year period, of which 9718 (59%, 95% CI 58% to 60%) were tested for hepatitis A IgG. There was a 2% annual increase in the proportion of men tested (from 60% in 2012 to 69% in 2018; OR=1.02, 95% CI 1.00 to 1.03, p=0.025). Men born outside of Australia/New Zealand, and younger men <30 years had higher odds of being tested. Of those tested, 44% (n=4304, 95% CI 43% to 45%) had hepatitis A IgG detected at their first visit, with no change over time (OR=1.01, 95% CI 0.99 to 1.03, p=0.210). Detection of hepatitis A IgG was associated with being aged 30 years or older (adjusted OR=2.06, 95% CI 1.89 to 2.24, p<0.001) or being born overseas versus Australia/New Zealand (AOR=1.21, 95% CI 1.11 to 1.31, p<0.001).

CONCLUSION

Hepatitis A immunity among MSM remains below the estimated 70% required to prevent outbreaks. Measures including increased testing and higher vaccination coverage are needed to prevent outbreaks and to limit the number of cases and deaths.

Bayesian modelling of a hepatitis A outbreak in men who have sex with men in Sydney, Australia, 1991/1992

To control hepatitis A spread by vaccination, accurate estimation of transmissibility is vital. Regan et al. (2016) proposed a model of hepatitis A virus (HAV) transmission and used least squares to calibrate model to the 1991/1992 HAV outbreak in men who have sex with men (MSM) in Sydney, Australia. Based on the estimate of R₀, they obtained the critical immunity of 70% and showed that when the proportion immune <70%, there is a definite chance for outbreaks to take place. The immunity level from previous surveys ranges from 32% to 64% after 1996 while no outbreaks in Australian MSMs have been reported since 1996. Further noticing the ill-distributed parameters, we argue that their estimate of R₀ is not accurate. In this study, we revisited their model by Bayesian inference, which has privilege over least squares. We obtained the appropriate posterior distributions of parameters and the estimate of R₀ ranges from 1.38 to 2.89, indicating a critical immunity of 65%. The reduction in critical immunity and outbreak probabilities predicts the absence of outbreaks in Australian MSMs since 1996. Our study shows the importance of using appropriate methods to provide reliable and accurate estimates of the model parameters especially the transmissibility.

Mycoplasma Genitalium and Mycoplasma Hominis are prevalent and correlated with HIV risk in MSM: a cross-sectional study in Shenyang, China

Background

A high proportion of men who have sex with men (MSM) use geosocial networking apps (Apps) to seek partners. However, the relationship of app use with HIV risk is unknown. Further, the risks of some sexually transmitted infection (STIs), including Mycoplasma genitalium, have seldom been studied among MSM.

Methods

MSM were enrolled at a community-based HIV testing site in Shenyang, China. After completing a questionnaire survey, we collected rectal swabs and venous blood specimens. We then simultaneously tested for ten STIs (Chlamydia trachomatis [CT], Neisseria gonorrhea [NG], Ureaplasma urealyticum [Uu], Ureaplasma parvum species [Up1, Up3, Up6, Up14), Mycoplasma hominis [Mh], Mycoplasma genitalium [Mg], and Herpes Simplex Virus Type 2 (HSV-2) using multiple PCR. We also performed blood tests for HIV, Syphilis, Hepatitis C antibody (HCV-Ab), Hepatitis B Surface Antigen (HBsAg), and Hepatitis A-IgM (HAV-IgM), etc.

Results

One hundred and eighty-three MSM participated in this study, of which 51.4% reported seeking partners through apps in the past year. The prevalence of HIV was 19.7%, Syphilis 12.0%, HAV 1.1%, rectal Mg 15.3% and Mh 7.1%. Multivariable logistic regression showed that HIV infection was independently correlated with app-using behavior (adjusted odds ratio[aOR] = 2.6), Mg infection (aOR = 3.2), Mh infection (aOR = 4.1) and Syphilis infection (aOR = 3.1) (each P < 0.05).

Conclusions

App use, Mg, Mh and Syphilis infection were correlated with higher HIV Risk in MSM. Geosocial networking apps should be utilized for HIV interventions targeting MSM. There is a need for more expansive STIs screening, particularly for Mg, Mh and Syphilis in MSM.

Hepatitis A incidence, seroprevalence, and vaccination decision among MSM in Amsterdam, the Netherlands

BACKGROUND

Several outbreaks of Hepatitis A virus (HAV) were recently documented among men who have sex with men (MSM) in Europe. We investigated the HAV incidence among MSM in Amsterdam, the Netherlands; and HAV seroprevalence and HAV vaccination decision among MSM visiting the Sexually Transmitted Infection (STI) clinic in Amsterdam.

METHODS

Using surveillance data from 1992 to 2017 of MSM with acute HAV in Amsterdam, we estimated the incidence by calendar year and age. We explored HAV seroprevalence by calendar year and age, determinants for HAV seropositivity, and opting-in/out for HAV vaccination using data collected among MSM that visited the STI clinic between 2006 and 2017 and were included in a nationwide Hepatitis B virus (HBV) vaccination programme. Offering HAV vaccination at the STI clinic differed over three consecutive periods: not offered, offered for free, or offered for 75 euros. Logistic regression analyses were used to explore determinants.

RESULTS

HAV incidence increased in 2016/17 after 4 years of absence and peaked in MSM around 35 years of age. Among MSM visiting the STI clinic, HAV seroprevalence was 37% (95%CI = 35-40%), which was constant over the period 2006-2017, and increased with age (p < 0.001). Determinants for HAV seropositivity in multivariable analysis were: older age (p < 0.001), originating from an HAV endemic country (p < 0.001), and being HBV seropositive (p = 0.001). MSM opted-in more frequently when HAV vaccination was offered for free versus paid (89% versus 11%, respectively; p < 0.001). Younger MSM were less inclined to vaccinate when payment was required (p = 0.010). Post-hoc analyses showed that 98% versus 46% of MSM visiting the Amsterdam STI clinic would be protected against HAV infection if HAV vaccination was offered for free or for 75 euros, respectively.

CONCLUSIONS

The MSM population of Amsterdam is vulnerable to a new HAV outbreak. We strongly recommend that MSM have access to free hepatitis A vaccination.

Outbreak of hepatitis A virus infection in Taiwan, June 2015 to September 2017

The Taiwan Centers for Disease Control (CDC) were notified of increasing acute hepatitis A (AHA) in June 2015. Serum and/or stool from AHA patients and sewage samples were tested for hepatitis A virus (HAV). We defined outbreak cases as AHA patients with illness onset after June 2015 and with an HAV sequence less than 0.5% different from that of the TA-15 outbreak strain. We analysed characteristics and food exposures between outbreak and non-outbreak cases between January 2014 (start of enhanced surveillance) and February 2016. From June 2015 to September 2017, there were 1,563 AHA patients with a median age of 31 years (interquartile range (IQR): 26-38); the male-to-female ratio was 8.8 and 585 (37%) had human immunodeficiency virus (HIV) infection. TA-15 was detected in 82% (852/1,033) of AHA patients, and 14% (74/540) of sewage samples tested since July 2015. Infection with the TA-15 strain was associated with having HIV, sexually transmitted infections (STI), recent oral-anal sex and men who have sex with men (MSM). The Taiwan CDC implemented an HAV vaccine campaign starting from October 2016 where 62% (15,487/24,879) of people at risk were vaccinated against HAV. We recommend HAV vaccination for at-risk populations and continuous surveillance to monitor control measures.

Acute hepatitis due to hepatitis A virus during the 2017 epidemic expansion in Asturias. Spain

INTRODUCTION

Since June 2016, there has been an increase in cases of acute hepatitis A (AHA) in several European countries, mainly affecting men who have sex with men (MSM). The aim was to know the characteristics of AHA diagnosed in recent months, comparing them with a previous series.

PATIENTS AND METHODS

All cases of AHA diagnosed in adults between November 2016 and December 2017 (G-I; n=108) were prospectively collected and compared with a series also prospectively collected between January 2004 and September 2016 (G-II; n=49), analysing clinical and epidemiological characteristics.

RESULTS

Compared with group II, in group I there was a greater proportion of males (95.4 vs. 81.6%; p=0.005), of MSM (63.9 vs. 22.4%; p<0.001), of cases with positive luetic serology (20.4 vs 2%; p=0.001) and of severe acute hepatitis (15 vs. 4%; p=0.043).

CONCLUSIONS

AHA diagnosed in recent months in our environment mainly affect MSM and have a more serious presentation with respect to what was observed in a historical series, highlighting the need to increase the vaccination rate against the hepatitis A virus.

Trends and risk factors of hepatitis A in Catalonia after the introduction of a hepatitis A+B vaccination programme

At the end of 1998, universal hepatitis A+B vaccination of 12 year olds was introduced in Catalonia. The aim was to examine trends in hepatitis A during 2005-2015 and assess risk factors by age group. We carried out an observational epidemiological study of the incidence and risk factors of hepatitis A reported to the surveillance system. Information on exposure was recorded for each case for the 2-6 weeks before symptom onset. Spearman's coefficient was used to evaluate the trends of rates. The chi-square test was used to compare categorical. We studied 2621 hepatitis A cases; the age mean was 26.6 years (SD=18.2), and >50% of cases were in the 20-49 years age group. The incidence decreased from 3.28/100 000 in 2005 to 1.50/100 000 in 2015. The rate for women decreased over time (P = .008), but the reduction was not significant in men (P = .234). Men consistently had higher rates than women with the biggest difference being in the 20-34 years age group (rate 8.8 vs 2.8). The greatest risk factor was travel to an endemic country (42.1%) in the 0-19 years age group and male-to-male sexual contact (18.6%) in the 20-49 years age group. The case fatality rate in adults aged >49 years was 0.4%. In conclusion, the vaccination programme of preadolescents resulted in a reduction in hepatitis A cases. However, a significant amount of cases still appear in immigrants and men who have sex with men. Hepatitis A in adults is an emerging health problem that will require new strategies.

Incidence of acute hepatitis A among HIV-positive patients during an outbreak among MSM in Taiwan: Impact of HAV vaccination

BACKGROUND

An unprecedented outbreak of acute hepatitis A has occurred among MSM in Taiwan since June 2015. We aimed to describe the seroepidemiology of HAV infection and to investigate the relationship between HAV vaccination and the incidence of acute hepatitis A among HIV-positive patients at the largest designated hospital for HIV care during the outbreak.

METHODS

Between 2012 and 2016, the HAV serostatus, vaccination history and clinical characteristics of HIV-positive patients were retrospectively reviewed. A case-control study was performed to identify the factors associated with acute hepatitis A. The trends of HAV vaccination rate and incidence of acute hepatitis A among HAV-seronegative patients were examined during the outbreak.

RESULTS

During the 4.5-year period, 2088 HIV-positive patients with a mean age of 37.7 years and 90.2% being MSM were included. The overall HAV seroprevalence was 34.3%, which was significantly higher in older and non-MSM patients. The estimated incidence rate of acute hepatitis A was 52.6 cases per 1000 person-years of follow-up during the outbreak. The associated factors with acquiring acute hepatitis A were recent syphilis and having not received HAV vaccines. The HAV vaccination rate during the outbreak increased from 4.7% to 70.6% and the incidence rate of acute hepatitis A declined when up to 65% of the patients were immunized or tested positive for HAV.

CONCLUSIONS

The seroprevalence of HAV infection was low in the younger HIV-positive individuals. Prevention of acute hepatitis A was achieved among HIV-positive, HAV-seronegative patients through HAV vaccination and increased herd immunity during the ongoing outbreak.

Hepatitis A virus infection and hepatitis A vaccination in human immunodeficiency virus-positive patients: A review

Hepatitis A virus (HAV) is one of the most common infectious etiologies of acute hepatitis worldwide. The virus is known to be transmitted fecal-orally, resulting in symptoms ranging from asymptomatic infection to fulminant hepatitis. HAV can also be transmitted through oral-anal sex. Residents from regions of low endemicity for HAV infection often remain susceptible in their adulthood. Therefore, clustered HAV infections or outbreaks of acute hepatitis A among men who have sex with men and injecting drug users have been reported in countries of low endemicity for HAV infection. The duration of HAV viremia and stool shedding of HAV may be longer in human immunodeficiency virus (HIV)-positive individuals compared to HIV-negative individuals with acute hepatitis A. Current guidelines recommend HAV vaccination for individuals with increased risks of exposure to HAV (such as from injecting drug use, oral-anal sex, travel to or residence in endemic areas, frequent clotting factor or blood transfusions) or with increased risks of fulminant disease (such as those with chronic hepatitis). The seroconversion rates following the recommended standard adult dosing schedule (2 doses of HAVRIX 1440 U or VAQTA 50 U administered 6-12 mo apart) are lower among HIV-positive individuals compared to HIV-negative individuals. While the response rates may be augmented by adding a booster dose at week 4 sandwiched between the first dose and the 6-mo dose, the need of booster vaccination remain less clear among HIV-positive individuals who have lost anti-HAV antibodies.

Estimating the critical immunity threshold for preventing hepatitis A outbreaks in men who have sex with men

Several outbreaks of hepatitis A in men who have sex with men (MSM) were reported in the 1980s and 1990s in Australia and other countries. An effective hepatitis A virus (HAV) vaccine has been available in Australia since 1994 and is recommended for high-risk groups including MSM. No outbreaks of hepatitis A in Australian MSM have been reported since 1996. In this study, we aimed to estimate HAV transmissibility in MSM populations in order to inform targets for vaccine coverage in such populations. We used mathematical models of HAV transmission in a MSM population to estimate the basic reproduction number (R 0) and the probability of an HAV epidemic occurring as a function of the immune proportion. We estimated a plausible range for R 0 of 1·71-3·67 for HAV in MSM and that sustained epidemics cannot occur once the proportion immune to HAV is greater than ~70%. To our knowledge this is the first estimate of R 0 and the critical population immunity threshold for HAV transmission in MSM. As HAV is no longer endemic in Australia or in most other developed countries, vaccination is the only means of maintaining population immunity >70%. Our findings provide impetus to promote HAV vaccination in high-risk groups such as MSM.

Changes in the epidemiology of hepatitis A outbreaks 13 years after the introduction of a mass vaccination program

A hepatitis A+B vaccine vaccination program of 12-year-olds was introduced in Catalonia in 1998. The aim of this study was to investigate the evolution of hepatitis A outbreaks in Catalonia and estimate the preventable fraction of cases associated with outbreaks as a measure of the impact of the vaccination program. Hepatitis A outbreaks reported to the Health Department between 1991 and 2012 were analyzed. The incidence rates of outbreaks, outbreak-associated cases and hospitalizations were calculated. The preventable fraction (PF) and 95% confidence intervals (CI) were estimated for the whole study period (pre-vaccination and post-vaccination) and the post-vaccination period.   One-hundred-eight (108) outbreaks (rate of 2.21 per 10(6) persons-year) were reported in the pre-vaccination period and 258 outbreaks (rate of 2.82 per 10(6) persons-year) in the post-vaccination period. The rate of cases associated with outbreaks was 1.52 per 10(5) persons-year in the pre-vaccination period and 1.28 per 10(5) persons-year in the post-vaccination period. Hospitalization rates were 0.08 and 0.75 per 10(6) persons-year, respectively. The number of person-to-person outbreaks whose index case was a school contact decreased in the post-vaccination period (aOR 2.72; 95%CI 1.35-5.48), but outbreaks whose index case was a man who has sex with men (MSM) or an immigrant increased. The PF of all outbreak-associated cases was 6.46% (95%CI 3.11-9.82) and the highest PF was in the 15-24 years age group (42.53%; 95%CI 29.30-55.75). In the 0-4 years age group, the PF was 18.35% (95%CI 9.59-27.11), suggesting a protective herd effect in unvaccinated subjects. Vaccination of immigrants traveling to endemic countries and MSM should be reinforced.

Australian sexually transmissible infection and HIV testing guidelines for asymptomatic men who have sex with men 2014: a review of the evidence

Men who have sex with men (MSM) in Australia and overseas are disproportionately affected by sexually transmissible infections (STIs), including HIV. Many STIs are asymptomatic, so regular testing and management of asymptomatic MSM remains an important component of effective control. We reviewed articles from January 2009–May 2013 to inform the 2014 update of the 2010 Australian testing guidelines for asymptomatic MSM. Key changes include: a recommendation for pharyngeal chlamydia (Chlamydia trachomatis) testing, use of nucleic acid amplification tests alone for gonorrhoea (Neisseria gonorrhoeae) testing (without gonococcal culture), more frequent (up to four times a year) gonorrhoea and chlamydia testing in sexually active HIV-positive MSM, time required since last void for chlamydia first-void urine collection specified at 20 min, urethral meatal swab as an alternative to first-void urine for urethral chlamydia testing, and the use of electronic reminders to increase STI and HIV retesting rates among MSM.