2-Year GLOBE trial results: telbivudine Is superior to lamivudine in patients with chronic hepatitis B

BACKGROUND & AIMS

The GLOBE trial has compared the efficacy and safety of telbivudine versus lamivudine treatment over 2 years in patients with chronic hepatitis B.

METHODS

Hepatitis B e antigen (HBeAg)-positive (n = 921) and HBeAg-negative (n = 446) patients received telbivudine or lamivudine once daily for 104 weeks. The primary outcome, assessed in the intent-to-treat population, was therapeutic response (hepatitis B virus DNA <5 log(10) copies/mL and either HBeAg loss or normalization of alanine aminotransferase [ALT] level).

RESULTS

The therapeutic response to telbivudine was superior to that of lamivudine in HBeAg-positive (63% vs 48%; P < .001) and HBeAg-negative (78% vs 66%; P = .007) patients. HBeAg-positive patients given telbivudine also had better outcomes compared with lamivudine in terms of nondetectable viremia (< 300 copies/mL) at 55.6% versus 38.5% (P < .001), HBeAg loss at 35.2% versus 29.2% (P = .056), and viral resistance at 25.1% versus 39.5% (P < .001). Hepatitis B e antigen seroconversion was 29.6% versus 24.7% (P = .095) in all patients and 36% versus 27% (P = .022) in patients with baseline ALT level > or = 2 times normal. Telbivudine-treated HBeAg-negative patients showed higher rates of nondetectable viremia compared with lamivudine at 82.0% versus 56.7% (P < .001) and less resistance at 10.8% versus 25.9% (P < .001). Adverse events occurred with similar frequency, whereas grade 3/4 increases in creatine kinase levels were more common in patients given telbivudine (12.9% vs 4.1%, P < .001). Multivariate logistic regression analyses identified telbivudine treatment, among other variables, as an independent predictor of better week 104 outcomes.

CONCLUSIONS

Telbivudine is superior to lamivudine in treating patients with chronic hepatitis B over a 2-year period.

Incidence of Herpes Zoster, Before and After Varicella‐Vaccination–Associated Decreases in the Incidence of Varicella, 1992–2002

BACKGROUND

Varicella zoster virus (VZV) causes varicella and, later in the life of the host, may reactivate to cause herpes zoster (HZ). Because it is hypothesized that exposure to varicella may boost immunity to latent VZV, the vaccination-associated decrease in varicella disease has led some to suggest that the incidence of HZ might increase. We assessed the impact that varicella vaccination has on the incidence of varicella and of HZ.

METHODS

Codes for cases of varicella and of HZ in an HMO were determined in automated databases of inpatients and outpatients, on the basis of the Ninth Revision of the International Classification of Diseases. We calculated the incidence, during 1992-2002, of varicella and of HZ.

RESULTS

The incidence of HZ remained stable as the incidence of varicella decreased. Age-adjusted and -specific annual incidence rates of varicella decreased steadily, starting with 1999. The age-adjusted rates decreased from 2.63 cases/1000 person-years during 1995 to 0.92 cases/1000 person-years during 2002; among children 1-4 years old, there was a 75% decrease between 1992-1996 and 2002. Age-adjusted and -specific annual incidence rates of HZ fluctuated slightly over time; the age-adjusted rate was highest, at 4.05 cases/1000 person-years, in 1992, and was 3.71 cases/1000 person-years in 2002.

CONCLUSIONS

Our findings revealed that the vaccination-associated decrease in varicella disease did not result in an increase in the incidence of HZ. These early findings will have to be confirmed as the incidence of varicella disease continues to decrease.

Development and Experience with an Algorithm to Evaluate Suspected Smallpox Cases in the United States, 2002-2004

Concerns that smallpox, an eradicated disease, might reappear because of a bioterror attack and limited experience with smallpox diagnosis in the United States prompted us to design a clinical algorithm. We used clinical features of classic smallpox to classify persons presenting with suspected smallpox rashes into 3 categories: those with high, those with moderate, and those with low risk of having smallpox. The classification guides subsequent diagnostic strategies, limiting smallpox laboratory testing to high-risk persons to minimize the number of false-positive test results. From January 2002 through June 2004, the Centers for Disease Control and Prevention (CDC) received 43 consultations regarding suspected smallpox cases. No patient was at high risk for having smallpox. One patient was tested for the presence of variola virus. Varicella was the diagnosis for 23 cases (53%). The algorithm worked well to guide clinical and public health responses to suspected smallpox cases. The poster is available from CDC, and an interactive version and laboratory protocol are available at http://www.bt.cdc.gov/agent/smallpox/diagnosis/riskalgorithm/index.asp. We recommend use of the algorithm in the United States and elsewhere.

Postpartum varicella vaccination: is the vaccine virus excreted in breast milk?

OBJECTIVE

To evaluate whether the varicella vaccine virus is detected in breast milk after vaccination of breast-feeding women and whether there is serologic evidence of exposure of the infant to varicella virus after maternal vaccination.

METHODS

We enrolled women identified as varicella seronegative during routine prenatal screening at Group Health Cooperative. Participants received the first dose of varicella vaccine at least 6 weeks postpartum and the second dose at least 4 weeks later. They collected ten breast milk samples after each vaccine dose. Breast milk samples were tested for varicella zoster virus by polymerase chain reaction (PCR). Serum specimens were collected from the mothers 1 month after each vaccine dose, and peripheral blood from their infants was collected onto filter spots 1 month after the mother's second dose. These samples were tested for varicella immunoglobulin (Ig) G by whole-virus enzyme-linked immunosorbent assay (ELISA), or by the more sensitive glycoprotein ELISA. When possible, filter spots from the infants were also tested by PCR for the presence of varicella zoster virus deoxyribonucleic acid (DNA).

RESULTS

Twelve women were enrolled; all seroconverted after the first vaccine dose. Varicella DNA was not detected by PCR in any of the 217 postvaccination breast milk specimens. None of the infants was seropositive. Samples from six infants were tested for varicella zoster virus DNA by PCR, and all were negative.

CONCLUSION

We found no evidence of varicella vaccine virus excretion in breast milk. These findings suggest that postpartum vaccination of varicella-susceptible women need not be delayed because of breast-feeding.

Outbreak of varicella at a day-care center despite vaccination

BACKGROUND

In seven studies of the effectiveness of the varicella vaccine conducted since it was licensed, the effectiveness was 71 to 100 percent against disease of any severity and 95 to 100 percent against moderate and severe disease. We investigated an outbreak of varicella in a population of children with a high proportion of vaccinees who were attending a day-care center in a small community in New Hampshire.

METHODS

Using standardized questionnaires, we collected information about the children's medical and vaccination history from parents and health care providers. The analysis of the effectiveness of the vaccine and of risk factors for vaccine failure was restricted to children who were enrolled in the day-care center continuously during the outbreak and attended for one week or more and who were cared for in the building that represented the epicenter of the outbreak, since transmission was not documented in a second building.

RESULTS

Varicella developed in 25 of 88 children (28.4 percent) between December 1, 2000, and January 11, 2001. The index case occurred in a healthy child who had been vaccinated three years previously and who infected more than 50 percent of his classmates who had no history of varicella. The effectiveness of the vaccine was 44.0 percent (95 percent confidence interval, 6.9 to 66.3 percent) against disease of any severity and 86.0 percent (95 percent confidence interval, 38.7 to 96.8 percent) against moderate or severe disease. Children who had been vaccinated three years or more before the outbreak were at greater risk for vaccine failure than those who had been vaccinated more recently (relative risk, 2.6 [95 percent confidence interval, 1.3 to 5.3]).

CONCLUSIONS

In this outbreak, vaccination provided poor protection against varicella, although there was good protection against moderate or severe disease. A longer interval since vaccination was associated with an increased risk of vaccine failure. Breakthrough infections in vaccinated, healthy persons can be as infectious as varicella in unvaccinated persons.

Hospitalizations for varicella in the United States, 1988 to 1999

BACKGROUND

Varicella epidemiology is changing with increasing use of the varicella vaccine.

METHODS

To describe the epidemiology of severe varicella disease before and after vaccine introduction, data from the National Hospital Discharge Survey (NHDS) for 1988 to 1999 were analyzed. Incidental cases of varicella in persons hospitalized for a different indication were excluded.

RESULTS

In the prevaccination era (1988 to 1995), there were 10 632 varicella hospitalizations annually. The most common complications were viral pneumonitis (20.9%), fluid/electrolyte disturbances (19.3%) and soft tissue infections (17.8%). Most (89.1%) persons had no severe underlying immunocompromising conditions. The mean length of hospitalization was 5.4 days, corresponding to approximately 57 000 days of hospitalization annually. In the first years after vaccine licensure (1996 to 1999), vaccine coverage reached 59%. Although not statistically significant, there was a trend toward decreased hospitalizations and a decline in mean length of hospitalization.

CONCLUSIONS

Varicella morbidity was higher in the prevaccination era than previously reported. Although no significant decline is evident, a trend toward decreased hospitalizations is emerging in the first years after vaccine introduction.

Resistance to reinfection with Schistosoma mansoni in occupationally exposed adults and effect of HIV-1 co-infection on susceptibility to schistosomiasis: a longitudinal study

BACKGROUND

Previous studies have reported age-dependent development of resistance to reinfection by schistosomes and identified immunological correlates of this resistance. However, whether resistance exists that is independent of age effects has been questioned. We did a longitudinal investigation of reinfection by Schistosoma mansoni in an adult population with high occupational exposure.

METHODS

We monitored a cohort of 96 male car washers working along the shores of Lake Victoria, Kenya during 349.7 person-years for frequency of water contact and infection with S mansoni. Patients were treated with praziquantel upon study entry and after reinfection with S mansoni. Bivariate analyses and a multivariate proportional hazards model were used to assess the effects of water contact, previous infections, and HIV-1 on S mansoni reinfection rates.

FINDINGS

13 car washers did not get reinfected or only became reinfected after an extended time (91 weeks). 47 initially had a short time to reinfection (15 weeks) but on subsequent treatments showed increased time to reinfection (29-38 weeks). 36 consistently displayed short times to reinfection (<15 weeks) despite multiple reinfection and treatment cycles. Decreased CD4 T-cell counts in HIV-1-positive individuals corresponded to increased susceptibility to S mansoni reinfection.

INTERPRETATION

Adults similarly exposed to schistosomiasis are either resistant to reinfection; susceptible, but develop resistance to reinfection after multiple treatments; or remain susceptible to reinfection. Thus, immunological resistance to reinfection with S mansoni exists or can develop independent of age effects. The consequence of HIV-1 co-infection suggests that CD4 T cells contribute to this resistance.

Younger age at vaccination may increase risk of varicella vaccine failure

To determine vaccine effectiveness (VE), a varicella outbreak in a highly vaccinated day-care center (DCC) population in Pennsylvania was investigated. In Pennsylvania, proof of immunity is required for children >or=12 months old for DCC enrollment. Questionnaires were administered to parents of children who had attended the DCC continuously during the study period (1 November 1999-9 April 2000) to determine history of varicella disease or vaccination and for information about any recent rash illnesses. VE was calculated for children >or=12 months old without a history of varicella. There were 41 cases of varicella among 131 attendees, with 14 cases (34%) among vaccinated children. VE was 79% against all varicella and 95% against moderate or severe varicella. Vaccination at <14 months was associated with an increased risk of breakthrough disease (relative risk, 3.0; 95% confidence interval, 0.9-9.9). Despite varicella vaccination coverage of 80%, a sizeable outbreak occurred. Early age at vaccination may increase the risk of vaccine failure.

Varicella vaccine exposure during pregnancy: data from the first 5 years of the pregnancy registry

OBJECTIVE

To assess the risks of congenital varicella syndrome and other birth defects in offspring of women who inadvertently received varicella vaccine during pregnancy or within 3 months of conception.

METHODS

Pregnant women inadvertently exposed to varicella vaccine, reported voluntarily, were enrolled in the Pregnancy Registry for VARIVAX (Merck & Co., Inc., West Point, PA). The pregnancies were monitored and the outcomes ascertained from questionnaires completed voluntarily by the health care providers. The rates of congenital varicella syndrome and congenital anomalies were calculated for seronegative women prospectively reported to the registry.

RESULTS

From March 17, 1995 through March 16, 2000, 362 pregnancy outcomes were identified from prospective reports. Ninety-two women were known to be seronegative to varicella, of whom 58 received their first dose of vaccine during the first or second trimester. No cases of congenital varicella syndrome were identified among 56 live births (rate 0%, 95% confidence interval [CI] 0, 15.6). Among all the prospective reports of live births, five congenital anomalies were reported. No specific pattern was identified in either the susceptible cohort or the sample population as a whole.

CONCLUSION

No abnormal features have been reported that suggested the occurrence of congenital varicella syndrome or other birth defects related to vaccine exposure during pregnancy. Because of the small numbers, this study has limited precision, so continued surveillance is warranted. However, these results should provide some assurance to health care providers and women with inadvertent exposure before or during pregnancy.

The use of school-based vaccination clinics to control varicella outbreaks in two schools

School-based vaccination clinics were offered in 2 schools experiencing varicella outbreaks. The clinics raised coverage of susceptible children from 52.9% to 92.2% and from 68.8% to 85.3% in the 2 schools, respectively. Although routine immunization and school-entry requirements are the best strategies for preventing outbreaks, school-based vaccination clinics may greatly increase coverage and shorten outbreaks.

Reemergence of invasive Haemophilus influenzae type b disease in a well-vaccinated population in remote Alaska

Before vaccination, Alaska Natives experienced very high rates of invasive Haemophilus influenzae type b (Hib) disease and carriage. Vaccination with Hib conjugate vaccine PRP-OMP (polyribosylribitol phosphate Neisseria meningitidis outer membrane protein) began in 1991 and resulted in a sharp decline in cases. In 1996, after switching to a different Hib conjugate vaccine, DTP-HbOC (which combines diphtheria-tetanus-whole cell pertussis vaccines with HbOC [Hib oligosaccharide CRM197]), cases of invasive Hib disease increased, suggesting ongoing Hib transmission despite widespread vaccination. To determine the prevalence of and risk factors for carriage, a cross-sectional study of oropharyngeal Hib carriage was conducted among Alaska Native children aged 1-5 years in remote southwestern Alaska. Of 496 children with swabs taken, 46 (9.3%) were colonized with Hib. Carriage rates varied by village from 2.2% to 13.2% and by age from 6.1% in 1-year-olds to 14.7% in 5-year-olds. Crowding was associated with Hib carriage. Widespread vaccination with PRP-OMP Hib conjugate vaccine did not eliminate carriage in this population of Alaska Natives, and ongoing carriage contributed to disease resurgence.

Abscesses due to mycobacterium abscessus linked to injection of unapproved alternative medication

An unlicensed injectable medicine sold as adrenal cortex extract (ACE*) and distributed in the alternative medicine community led to the largest outbreak of Mycobacterium abscessus infections reported in the United States. Records from the implicated distributor from January 1, 1995, to August 18, 1996, were used to identify purchasers; purchasers and public health alerts were used to identify patients. Purchasers and patients were interviewed, and available medical records were reviewed. Vials of ACE* were tested for mycobacterial contamination, and the product was recalled by the U.S. Food and Drug Administration. ACE* had been distributed to 148 purchasers in 30 states; 87 persons with postinjection abscesses attributable to the product were identified. Patient and vial cultures contained M. abscessus identical by enzymatic and molecular typing methods. Unusual infectious agents and alternative health practices should be considered in the diagnosis of infections that do not respond to routine treatment.

The sequelae of herpes zoster

BACKGROUND

The last 40 years was a period during which the incidence of herpes zoster appears to have increased substantially.

OBJECTIVE

To determine whether the risk of complications of herpes zoster has changed during the last 40 years.

METHODS

The automated medical records of a health maintenance organization were screened for diagnosis codes suggesting herpes zoster and potentially complicated cases of zoster. The predictive value of a herpes zoster diagnosis was calculated from sampling full-text records. Records of all patients with codes suggesting complications were reviewed in full.

RESULTS

Of 859 individuals with herpes zoster who met the eligibility criteria, 101 were identified who experienced at least 1 complication, corresponding to a 60-day risk of 12%. Corrected for the sensitivity of the complication-finding strategy, the risk estimate was 14%. Risk increased markedly with age, with those older than 64 years having more than 6 times the risk of complications of those younger than 25 years (odds ratio, 8.3; 95% confidence interval, 2.5-29.3). Trigeminal distribution of rash and the presence of certain conditions associated with immune compromise appeared to increase risk.

CONCLUSIONS

The apparent increase in the incidence of herpes zoster was not accompanied by a change in the risk of specific or overall complications in a population-based sample. Advanced age and other conditions associated with waning cellular immunity may confer an increased risk of experiencing a complicated course of herpes zoster.

Risk factors for postherpetic neuralgia

BACKGROUND

The risk factors for postherpetic neuralgia (PHN), the most common complication of herpes zoster, have not been well established.

OBJECTIVE

To elucidate the risk factors for PHN.

METHODS

Automated medical, claims, and pharmacy records of a health maintenance organization were used to identify cases of PHN and obtain data on risk factors. A case-base design was used to assess the impact of various patient, disease, and treatment factors on the prevalence of PHN 1 and 2 months after developing zoster.

RESULTS

There were 821 cases of herpes zoster that met all eligibility criteria. The prevalence of PHN more than 30 days after onset of zoster was 8.0% (95% confidence interval [CI], 6.3%-10.1%) and 4.5% (95% CI, 3.2%-6.2%) after 60 days. Compared with patients younger than 50 years, individuals aged 50 years or older had a 14.7-fold higher prevalence (95% CI, 6.8-32.0) 30 days and a 27.4-fold higher prevalence (95% CI, 8.8-85.4) 60 days after developing zoster. Prodromal sensory symptoms and certain conditions associated with compromised immunity were also associated with PHN. Systemic corticosteroids before zoster and treatment of zoster with acyclovir or corticosteroids did not significantly affect the prevalence of PHN.

CONCLUSIONS

Increased age and prodromal symptoms are associated with higher prevalence of PHN 1 and 2 months after onset of zoster. Overall, systemic acyclovir appears not to confer any protection against PHN, although benefit among elderly patients cannot be excluded.