Study challenges concerns on effectiveness of administering pneumococcal, shingles vaccines together

ScienceDaily (May 11, 2011) — Administering both the pneumococcal and the herpes zoster vaccines to patients during the same visit is beneficial and does not appear to compromise the protective effect of the zoster vaccine, according to a Kaiser Permanente study published in the journal Vaccine.

The study's findings challenge information in the zoster vaccine manufacturer's package insert. This new information is important to patients who find it more convenient and less costly to receive both vaccines from their health care providers during the same visit.

A revision to the zoster vaccine package insert, approved in 2009, stated that the zoster vaccine and the pneumococcal vaccine should not be given together because such concurrent use reduced the ability of the zoster vaccine to generate an immune response.

"Our study found no evidence that receiving the zoster vaccine and pneumococcal vaccine on the same day would compromise the immune response necessary to protect against herpes zoster, also known as shingles," noted study lead author Hung Fu Tseng, PhD, MPH, a research scientist with the Kaiser Permanente Department of Research & Evaluation in Pasadena, Calif.

The study was conducted from Jan. 1, 2007, to June 30, 2010, starting from the date of receipt of the zoster vaccine for two groups of Kaiser Permanente Southern California members, 60 years of age and older. The incidence of herpes zoster after vaccination with a zoster vaccine in the population receiving both vaccines on the same day was compared to that in the population receiving a pneumococcal vaccine from one year to 30 days before the zoster vaccine. Vaccinations and the incidence of herpes zoster cases were identified by electronic health records.

Included in the study were two groups or cohorts: 7,187 people who received both vaccines at the same time and 7,179 people who received the two vaccines at different times (nonconcurrently). There were 114 herpes zoster cases identified in the study: 56 cases in the concurrent group, and 58 cases in the nonconcurrent vaccination group. The study found no statistically significant difference in incidence of shingles between the two groups.

Dr. Tseng adds, "Ideally, when a new vaccine is introduced to the public, one should consider giving it at the same time as other vaccines to increase coverage levels and minimize administration costs, if there are no immune response issues or safety concerns."

According to the Centers for Disease Control and Prevention, pneumococcal polysaccharide vaccine protects against 23 types of pneumococcal bacteria, including those most likely to cause serious disease. Pneumococcal disease can result in long-term problems such as like brain damage, hearing loss and limb loss, and in some cases can be fatal. Most healthy adults who get the vaccine develop protection to most or all of these types within two to three weeks of getting the shot.

The risk of developing shingles during a lifetime is about 30 percent, and there are more than 1 million episodes of shingles every year in the United States. Shingles is a painful condition that can last months or years and can seriously impact quality of life. Less than 7 percent of the eligible U.S. population was vaccinated for herpes zoster by the end of 2008.

The CDC continues to recommend that the zoster vaccine and pneumococcal vaccine be administered at the same visit if the person is eligible for both vaccines.

The FDA approved the package label change in 2009 based on a research study by Merck that found antibody levels to the herpes zoster virus were lowered if the vaccine was administered concomitantly with pneumonia vaccine. However that study used the antibody level as the marker of protection, but it is the cell-mediated immunity against the herpes virus, instead of the antibody level that protects against the disease explained Dr. Tseng.

"This new study provides even stronger data because it relies on the measurement of the occurrence of disease rather than intermediate markers of immunity," Tseng said.

This study is the latest in a series of published Kaiser Permanente studies undertaken to better understand vaccine effectiveness and safety:

A study of 300,000 people published in JAMA earlier this year by Dr. Tseng found that receiving the herpes zoster vaccine was associated with a 55 percent reduced risk of developing shingles.Another Tseng study published in JAMA last year found the pneumococcal pneumonia vaccination is not associated with a reduced risk of heart attacks or strokes.Another Kaiser Permanente study found the combination vaccine for measles, mumps, rubella and chickenpox (MMRV) is associated with double the risk of febrile seizures for 1- to 2-year-old children compared to same-day administration of the separate vaccine for MMR (measles, mumps, rubella) and the varicella (V) vaccine for chickenpox.Other recent published Kaiser Permanente studies found children of parents who refuse vaccines are nine times more likely to get chickenpox and 23 times more likely to get whooping cough compared to fully immunized children. A study published last year found that herpes zoster, also known as shingles, is very rare among children who have been vaccinated against chickenpox.

Co-authors of the paper include Hung Fu Tseng, PhD, MPH, Ning Smith, PhD, Lina S. Sy, MPH, and Steven J. Jacobsen, MD, PhD, with Kaiser Permanente Department of Research & Evaluation.

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Journal Reference:

Hung Fu Tseng, Ning Smith, Lina S. Sy, Steven J. Jacobsen. Evaluation of the incidence of herpes zoster after concomitant administration of zoster vaccine and polysaccharide pneumococcal vaccine. Vaccine, 2011; 29 (20): 3628 DOI: 10.1016/j.vaccine.2011.03.018

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Cold sore virus may contribute to cognitive and brain abnormalities in schizophrenia

ScienceDaily (May 29, 2010) — Exposure to the common virus that causes cold sores may be partially responsible for shrinking regions of the brain and the loss of concentration skills, memory, coordinated movement and dexterity widely seen in patients with schizophrenia, according to research led by Johns Hopkins scientists.

"We're finding that some portion of cognitive impairment usually blamed solely on the disease of schizophrenia might actually be a combination of schizophrenia and prior exposure to herpes simplex virus 1 infection, which reproduces in the brain," says study leader David J. Schretlen, Ph.D., an associate professor in the Department of Psychiatry at Johns Hopkins University School of Medicine.

The research, described in the May Schizophrenia Research, could lead to new ways to treat or prevent the cognitive impairment that typically accompanies this mental illness, including with antiviral drugs, the scientists say.

Doctors have long known that cognitive impairment, including problems with psychomotor speed, concentration, learning, and memory, are prevalent features of schizophrenia, which affects an estimated one percent of the U.S. population. Cognitive deficits often surface months to years before symptoms that are traditionally used to diagnose this disease, such as delusions or hallucinations.

Some previous studies have shown that schizophrenic patients with antibodies to herpes simplex virus 1 (HSV-1), the virus that causes cold sores, often have more severe cognitive deficits than patients without these antibodies. Other studies have shown that patients with HSV-1 antibodies have decreased brain volumes compared to patients without the antibodies. However, it has been unclear whether the cognitive deficits are directly related to the decreased brain volume.

To investigate, Schretlen and his colleagues recruited 40 schizophrenic patients from outpatient clinics at the Johns Hopkins and Sheppard Enoch Pratt hospitals in Baltimore, Md. Blood tests showed that 25 of the patients had antibodies for HSV-1 and 15 didn't. The researchers gave all of the patients tests to measure speed of coordination, organizational skills and verbal memory. The patients then underwent MRI brain scans to measure the volume of particular regions of their brains.

As in previous studies, results showed that patients with antibodies to HSV-1 performed significantly worse on the cognitive tests than patients without the antibodies. But expanding on those earlier studies, analysis of the brain scans showed that the same patients who performed poorly on the tests also had reduced brain volume in the anterior cingulate, which controls processing speed and the ability to switch tasks. There was also shrinkage in the cerebellum, which controls motor function.

These results suggest that HSV-1 might be directly causing the cognitive deficits by attacking these brain regions, Schretlen says.

Though the researchers aren't sure why schizophrenia might make brains more vulnerable to a viral assault, Schretlen says the results already suggest new ways of treating the disorder. Data from other studies has shown that antiviral medications can reduce psychiatric symptoms in some patients with schizophrenia. "If we can identify schizophrenic patients with HSV-1 antibodies early on, it might be possible to reduce the risk or the extent of cognitive deficits," he adds.

Other Johns Hopkins researchers who participated in this study include Tracy D. Vannorsdall, Ph.D., Jessica M. Winicki, B.A., Takatoshi Hikida, M.D., Akira Sawa, M.D., Ph.D., Robert H. Yolken, M.D., and Nicola G. Cascella, M.D.

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Journal Reference:

David J. Schretlen, Tracy D. Vannorsdall, Jessica M. Winicki, Yaser Mushtaq, Takatoshi Hikida, Akira Sawa, Robert H. Yolken, Faith B. Dickerson, Nicola G. Cascella. Neuroanatomic and cognitive abnormalities related to herpes simplex virus type 1 in schizophrenia. Schizophrenia Research, 2010; 118 (1-3): 224 DOI: 10.1016/j.schres.2010.01.008

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Patients with COPD have higher risk of shingles, study finds

ScienceDaily (Feb. 23, 2011) — Patients with chronic obstructive pulmonary disease (COPD) are at greater risk of shingles compared with the general population, according to a study published in CMAJ (Canadian Medical Association Journal). The risk is greatest for patients taking oral steroids to treat COPD.

Shingles, or herpes zoster, is a reactivation of the chicken pox virus resulting in a painful rash with lesions.

People with a compromised immune system are at greater risk of developing shingles although it has not been previously studied in patients with COPD.

There is increasing evidence that COPD is an autoimmune disease. "Given that various immune-mediated diseases, such as rheumatoid arthritis and inflammatory bowel disease, have been reported to be associated with an increased risk of herpes zoster, it is reasonable to hypothesize that immune dysregulation found in COPD may put patients at higher risk of developing herpes zoster," writes Dr. Hui-Wen Lin, Taipei Medical University, Taiwan with coauthors.

This study, using data from the Taiwan Longitudinal Health Insurance Database, included 8486 patients with COPD and 33 944 subjects from the comparison cohort. Of the total sample of 42 430 patients, 1080 had incident of herpes zoster during the follow-up period. There were 321 cases of shingles identified in the COPD cohort, 16.4 per 1000 person years, and 759 cases in the comparison cohort, 8.8 per 1000 person years.

"Our cohort study demonstrated that patients with COPD are at an increased risk of developing herpes zoster compared with the general population, after controlling for other herpes zoster risk factors," write the authors. "The risk of herpes zoster associated with COPD is greater for patients with inhaled or oral corticosteroids therapy than patients without."

The authors conclude it is possible that "increased disease severity further contributes to the increased risk of herpes zoster associated with COPD."

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Journal Reference:

Yang, Ya-Wen, Chen, Yi-Hua, Wang, Kuo-Hsien, Wang, Chen-Yi, Lin, Hui-Wen. Risk of herpes zoster among patients with chronic obstructive pulmonary disease: a population-based study. Canadian Medical Association Journal, 2011; DOI: 10.1503/cmaj.101137

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Pain of shingles (herpes zoster) significantly interferes with daily life

ScienceDaily (Oct. 4, 2010) — Acute herpes zoster, or shingles, interferes with all health areas for people with the condition, including sleep, enjoyment of life and general activities, according to a study published in CMAJ (Canadian Medical Association Journal).

Herpes zoster is a reactivation of the chicken pox (varicella-zoster) virus which results in pain and a rash with small blisters. It occurs in people who have had chicken pox and is most common in people over the age of 50, although younger people can have the condition. The lifetime risk of developing shingles is about 30%, but may increase as life expectancies increase.

Policymakers are being asked to consider implementing vaccination programs for the herpes zoster vaccine which is available as a preventative tool but more information is needed about the impact of shingles.

The MASTER study (Monitoring and Assessing Shingles Through Education and Research) was conducted in Canada to provide an in-depth understanding of the impact of shingles. The multi-centre study involved outpatients recruited through general practitioners or specialists across Canada.

"Acute herpes zoster significantly affected quality-of-life and functional status," writes Dr. Marc Brisson, Laval University, with coauthors. "Sleeping, enjoyment of life, general activities, mood, normal work and quality-of-life domains of pain/discomfort and usual activities were particularly diminished. This was consistently observed across all age groups."

The discomfort of shingles can also persist for months after the acute phase, with 24% of people in the study developing pain (postherpetic neuralgia) after the rash healed. The risk increased for older people.

The researchers conclude that this study reinforces "the need for effective prevention strategies, such as vaccination, and additional early intervention to reduce the burden of herpes zoster and postherpetic neuralgia."

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Persons with herpes simplex virus type 2, but without symptoms, still shed virus

ScienceDaily (Apr. 13, 2011) — Persons who have tested positive for herpes simplex virus type 2 (HSV-2) but do not have symptoms or genital lesions still experience virus shedding during subclinical (without clinical manifestations) episodes, suggesting a high risk of transmission from persons with unrecognized HSV-2 infection, according to a study in the April 13 issue of JAMA, a theme issue on infectious disease and immunology.

Anna Wald, M.D., M.P.H., of the University of Washington and Fred Hutchinson Cancer Research Center, Seattle, presented the findings of the study at a JAMA media briefing at the National Press Club in Washington, D.C.

"Herpes simplex virus type 2 is one of the most frequent sexually transmitted infections worldwide, with global estimates of 536 million infected persons and an annual incidence of 23.6 million cases among persons aged 15 to 49 years. In the United States, 16 percent of adults are HSV-2 seropositive, but only 10 percent to 25 percent of persons with HSV-2 infection have recognized genital herpes. Moreover, most HSV-2 infections are acquired from persons without a clinical history of genital herpes," according to background information in the article. Thus, the risk of sexual transmission does not correlate with the recognition of clinical signs and symptoms of HSV-2 but most likely correlates with the activity of the virus on the genital skin or mucosa (viral shedding).

Dr. Wald and colleagues compared the rates and patterns of genital HSV shedding in 498 immunocompetent HSV-2-seropositive persons between March 1992 and April 2008. Each participant obtained daily self-collected swabs of genital secretions for at least 30 days. The rate of viral shedding (the presence of virus that is actively replicating, and can thereby be transmitted to another person) was measured by polymerase chain reaction (testing method for viral DNA) from the swabs.

Among the findings of the researchers, HSV-2 was detected on 4,753 of 23,683 days (20.1 percent) in 410 persons with symptomatic genital HSV-2 infection compared with 519 of 5,070 days (10.2 percent) in 88 persons with asymptomatic infection. Genital HSV was detected at least once in 342 of 410 persons (83.4 percent) with symptomatic HSV-2 infection and in 60 of 88 (68.2 percent) persons with asymptomatic HSV-2 infection during the 2 month study.

Subclinical genital shedding rates were higher in persons with symptomatic infection compared with asymptomatic infection (2,708 of 20,735 [13.1 percent] vs. 434 of 4,929 [8.8 percent]). "However, the median [midpoint] amount of HSV detected during subclinical genital shedding episodes was similar in persons with symptomatic and asymptomatic infection," the authors write.

Persons with symptomatic infection had more frequent genital shedding episodes compared with persons with asymptomatic infection (median 17.9 vs. 12.5 episodes per year). Days with lesions accounted for 2,045 of 4,753 days (43.0 percent) with genital viral shedding among persons with symptomatic genital HSV-2 infection compared with 85 of 519 days (16.4 percent) among persons with asymptomatic infection. This indicates that the bulk of days of shedding in persons with asymptomatic HSV-2 is unrecognized, and people may engage in sexual activity not knowing that they are at risk for transmitting the virus to sexual partners.

"Our findings suggest that 'best practices' management of HSV-2-infected persons who learn that they are infected from serologic testing should include anticipatory guidance with regard to genital symptoms, as well as counseling about the potential for transmission. The issue of infectivity is both a patient management and a public health concern. The primary concern of many HSV-2-seropositive persons is the risk of transmission to sexual partners; in our experience this is the main source of angst in patients with genital herpes."

The researchers note that several methods have been identified that partly reduce the risk of HSV-2 transmission to sexual partners. "Condom use, daily valacyclovir therapy, and disclosure of HSV-2 serostatus each approximately halve the risk of HSV-2 transmission. However, these approaches reach a small portion of the population and have not had an influence on HSV-2 seroprevalence in the last decade. One of the reasons for such a limited effect is that few people are aware of their genital HSV-2 infection, and routine serologic testing, although available commercially, is recommended only in limited settings. We hope that these data will result in further discussions regarding control programs for HSV-2 in the United States."

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Journal Reference:

E. Tronstein, C. Johnston, M.-L. Huang, S. Selke, A. Magaret, T. Warren, L. Corey, A. Wald. Genital Shedding of Herpes Simplex Virus Among Symptomatic and Asymptomatic Persons With HSV-2 Infection. JAMA: The Journal of the American Medical Association, 2011; 305 (14): 1441 DOI: 10.1001/jama.2011.420

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Shingles may be related to elevated risk of multiple sclerosis

ScienceDaily (June 9, 2011) — Taiwanese investigators have found that there can be a significantly higher risk of multiple sclerosis (MS) occurring in the year following a shingles, or herpes zoster, attack. The findings, which support a long-held view on how MS may develop, are published in The Journal of Infectious Diseases and now available online.

MS is an autoimmune disease that affects the brain and spinal cord, leading to inflammation and nerve damage as the body's immune cells attack the nervous system. Possible causes that may trigger the inflammation include environmental, genetic, and viral factors. One virus that has been associated with MS is varicella zoster virus, the cause of herpes zoster.

In a study conducted by Herng-Ching Lin, PhD, and colleagues at Taipei Medical University in Taiwan, 315,550 adults with herpes zoster and a control group of 946,650 subjects were tracked and then evaluated for MS occurrence during a one-year follow-up period. The control group was selected randomly from a pool of subjects who had not been diagnosed with herpes zoster or other viral diseases. After adjusting for monthly income and geographic region, the authors found that the group with herpes zoster had a 3.96 times higher risk of developing MS than the control group. The authors noted that this risk, although increased, was still low, as is the frequency of MS in general. The study also noted an interval of approximately 100 days between a herpes zoster event and occurrence of MS.

Although the study was limited almost entirely to Han Chinese adults, the large scope of this nationwide case-controlled study, 1.26 million sampled patients, provides strong epidemiological evidence for a possible role for herpes zoster in the development of MS. The authors also point out that MS has a lower prevalence in Asian compared to Western populations and, thus, it may be difficult to project their findings to other populations.

In an accompanying editorial, Teresa Corona, MD, and Jose Flores, MD, of the National Institute of Neurology and Neurosurgery in Mexico noted that "The evidence provided in this study…allows us to better understand the role of these viral factors as an MS risk among certain genetically susceptible individuals," and that the study should be corroborated in other parts of the world to help clarify the role of this and other viruses in MS.

Fast Facts:

There is epidemiological evidence that some herpes viruses may contribute to multiple sclerosis (MS) occurrence.The rate of MS prevalence varies by geographical location and income.In this study, investigators found a significantly higher -- but still low -- risk for MS occurring in the year following a shingles, or herpes zoster, attack compared to a control population.There is evidence that 30 percent of relapses in MS patients may be associated with an infectious disease.Share this story on Facebook, Twitter, and Google:

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The above story is reprinted from materials provided by Infectious Diseases Society of America, via EurekAlert!, a service of AAAS.

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Journal References:

Jiunn-Horng Kang, Jau-Jiuan Sheu, Senyeong Kao and Herng-Ching Lin. Increased Risk of Multiple Sclerosis Following Herpes Zoster: A Nationwide, Population-Based Study. Journal of Infectious Diseases, June 7, 2011 DOI: 10.1093/infdis/jir239Teresa Corona and José Flores. Herpes Zoster and Multiple Sclerosis. Journal of Infectious Diseases, June 7, 2011 DOI: 10.1093/infdis/jir243

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Genital herpes more virulent in Africa than in US, report finds

ScienceDaily (Apr. 15, 2011) — Strains of genital herpes in Africa are far more virulent than those in the United States, researchers at Harvard Medical School report, a striking insight into a common disease with important implications for preventing HIV transmission in a region staggered by the HIV/AIDS epidemic. The researchers arrived at this finding by testing mouse model strains of the disease against vaccine candidates. All vaccines were far more efficacious in abating the U.S. strain.

The researchers say identification of the properties of the African viruses would open the door to developing a more potent vaccine against an infection now rampant in sub-Saharan Africa. This is important, they say, because genital herpes patients are more vulnerable to HIV/AIDS infection, as the open sores symptomatic of herpes contain a high concentration of immune cells that are targeted by HIV.

The challenge lies in formulating either a single vaccine that protects against both types of strains of the genital herpes virus or two different vaccines. The vaccine farthest along in development -- it is headed for clinical trials in about a year -- works best against the U.S. isolates of herpes simplex 2, but it also protects laboratory animals from the African viral strains if given in five-fold-higher doses.

This research, which appears online on April 15 in The Journal of Infectious Diseases, is led by David M. Knipe, the Higgins Professor of Microbiology and Molecular Genetics and vice chair of that department at Harvard Medical School, and Clyde Crumpacker, professor of medicine at Harvard Medical School and a physician in division of infectious disease at Beth Israel Deaconnes Medical Center. Their collaborators are former Knipe lab members Timothy E. Dudek, currently of the Ragon Institute of Massachusetts General Hospital, and Ernesto Torres-Lopez, now of the Universidad Autonoma in Monterrey, Mexico.

Live-virus vaccine

In southern Africa, infection rates among adults for genital herpes are exceedingly high -- from 80 percent to 90 percent in some groups compared to slightly less than 20 percent in the United States.

In evolutionary terms, the herpes viruses are very old. They have honed their talents to become efficient parasites in humans, often persisting for decades while causing limited or no disease symptoms -- although they can be deadly in immunocompromised persons and in newborns.

The herpes virus that causes ordinary cold sores, herpes simplex 1, is present in about 70 percent of the U.S. population. These stealthy viruses hide in nerve cells but can emerge over and over again, prompting repeated cold sore outbreaks.

Despite decades of research, there is no commercially available vaccine for herpes. But Knipe says their prototype vaccines are being tested in animals, and one such vaccine has been licensed to the French pharmaceutical firm Sanofi Pasteur.

According to Knipe, animal tests demonstrate clearly that the strains of herpes virus seen in sub-Saharan Africa are more virulent than the herpes simplex 2 virus strains seen in the United States. That difference suggests that an effective vaccine will probably have to be given to people in Africa in larger or more frequent doses. So far, says Knipe, results of animal tests are heartening.

Part of the promise in this work lies in the strong chance that a vaccine against herpes simplex 2 can help reduce the impact of HIV/AIDS in southern Africa. Epidemiological studies have shown that genital herpes infection is associated with a three-fold increase in the risk of HIV infection.

"If the rate of herpes infection can be reduced, it's conceivable the rate of HIV/AIDS infection will also come down, perhaps reducing the death rate," says Knipe.

Knipe's approach to vaccine development is based on using abnormal, live, mutant viruses to stimulate protective immune responses. These disabled viruses cannot multiply inside cells or cause symptomatic disease, but they do contain enough of the right proteins and molecules needed to arouse detection by a healthy immune system. Knipe's strategy is to trigger a strong immune response without causing disease.

"The candidate vaccine, ACAM529, is under development by Sanofi Pasteur, and under the current plan will enter phase I clinical testing in 2012," said Jim Tartaglia, a company respresentative. Phase I testing involves giving vaccine to a few human volunteers and watching for signs of toxicity. Trials for efficacy come later.

Although it has been difficult to create a vaccine for genital herpes, vaccines against a closely related herpes virus -- varicella zoster virus, the cause of chicken pox and shingles -- proved successful and are now widely used. This gives reason for optimism about a genital herpes vaccine.

The researchers do caution that, previously, two well-executed trials of Acyclovir, an effective, safe, antiviral drug for herpes, did decease the occurrence of genital herpes infections but failed to prevent transmission of HIV-1 in African study participants.

This research was funded by the National Institutes of Health.

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Journal Reference:

T. E. Dudek, E. Torres-Lopez, C. Crumpacker, D. M. Knipe. Evidence for Differences in Immunologic and Pathogenesis Properties of Herpes Simplex Virus 2 Strains From the United States and South Africa. Journal of Infectious Diseases, 2011; 203 (10): 1434 DOI: 10.1093/infdis/jir047

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