Ongoing Measles in the Developed and Developing World

Measles is a vaccine-preventable illness. Nevertheless, in recent years, measles is still endemic and epidemic in both the developed world and the developing world. The public perception of measles in the past was that it was not a big deal. However, measles is associated with a number of complications which can be places in three categories which are: acute(diarrhea, otitis media, pneumonia, encephalitis, seizures, and death) and delayed-subacute sclerosing panencephalitis (SSPE) and post-measles immune amnesia. Contrary to the beliefs of the anti-vaccine lobby, measles is bad. In acute measles, the death rate is 1-3 per 1000 and the risk of encephalitis is 1 per 1000. Relatively recent investigations indicate that SSPE is considerably more common than previously believed. The worldwide contribution of post-measles immune amnesia to morbidity and mortality is likely to be huge. In exposure situations, two doses of measles vaccine will prevent 99% of cases. Presently in the United States, the first dose is given at 12 through 15 months of age. The second dose is most often administered at 4 through 6 years of age. In my opinion, the second dose of measles vaccine should be given 4-6 weeks after the first dose rather than at 4-6 years of age. Children who don't have antibody to measles should not travel to risk areas.

Subacute Sclerosing Panencephalitis in Children: The Archetype of Non-Vaccination

Subacute sclerosing panencephalitis (SSPE) is a late complication of measles virus infection that occurs in previously healthy children. This disease has no specific cure and is associated with a high degree of disability and mortality. In recent years, there has been an increase in its incidence in relation to a reduction in vaccination adherence, accentuated by the COVID-19 pandemic. In this article, we take stock of the current evidence on SSPE and report our personal clinical experience. We emphasise that, to date, the only effective protection strategy against this disease is vaccination against the measles virus.

Subacute sclerosing panencephalitis in immunized Thai children

Subacute sclerosing panencephalitis (SSPE) is a progressive neurodegenerative disease with high mortality and poor prognosis. This is caused by persistent defective measles virus infection. Clinical presentations are variable including behavioral-cognitive change, myoclonic seizure, visual problem, spasticity or abnormal movement. The authors report a case of 10 year-old boy, previously healthy with complete immunization, presenting with frequent myoclonic jerks, abnormal movements, spasticity and altered mental status. Electroencephalographic (EEG), magnetic resonance imaging (MRI), and laboratory findings are typical for SSPE.

Subacute sclerosing panencephalitis in a tertiary care centre in post measles vaccination era

This study was conducted to observe the impact of measles vaccination on the epidemiology of subacute sclerosing panencephalitis (SSPE) in the post measles vaccination era. This is a retrospective study from a tertiary care hospital, covering a ten year period starting a decade after the introduction of the national measles immunization programme in India. We analyzed 458 serologically confirmed SSPE cases. These patients had a high cerebrospinal fluid: serum anti-measles antibody ratio. The male to female ratio in the present study was 4.4:1. The mean age at onset of SSPE was 13.3 years, showing an increase in mean age at onset of SSPE. Clinical and other demographic details, available from 72 in-patients, are discussed in this report. Of these, a history of measles could be elicited in 34 cases. Mean latent period between measles infection and onset of SSPE was 7.8 years. Six patients gave a history of measles vaccination. A sizable percentage (15.5 %) of the patients was > or = 18 years old and considered to have adult onset SSPE. The incidence of SSPE continues to be high and this report highlights the need for further strengthening routine measles immunization coverage.

[Epidemiological aspects of SSPE]

SSPE is neurodegenerative complication of slow measles infection in young children. In developing countries, SSPE has become rare disease because of widespread immunization for measles. However, in under developing countries, it is not rare disease. In Japan, widespread measles vaccination started in 1978. From 1981 SSPE cases declined to about 5 patients per year. We studied 114 cases with SSPE who were still alive in 2003. Incidence of SSPE elevated to near 10 cases per year in 1993-1998 coincident with decline of the rate of immunization for measles. After 1999, the incidence is under 5 cases per year. The immunization rate of young children increased to over 90%, SSPE will become rare disease near future. Future problem will be adult or infant onset of SSPE because of decreasing of anti measles virus titer, SSPE in immunosuppressive state including AIDS or post measles vaccination SSPE.

[SSPE virus and pathogenesis]

Subacute sclerosing panencephalitis (SSPE) is caused by particular mutants of measles virus, which are often referred to as SSPE virus. SSPE virus is characterized by (i) the inability to produce infectious viral particles, (ii) the neuropathogenicity in animal models as well as in humans, and (iii) the prolonged persistence in vivo over many years. The viral genome exhibits particular mutations, called biased hypermutation, most notably in the M gene, followed by the F and H genes. Consequently, the M, F and H proteins are mutated, which is thought to account for the characteristic features of SSPE virus. The possible mechanism of long-term persistence of the virus after the recovery of measles is also discussed.

Subacute sclerosing panencephalitis: more cases of this fatal disease are prevented by measles immunization than was previously recognized

BACKGROUND

The most severe sequela of measles virus infection is subacute sclerosing panencephalitis (SSPE), a fatal disease of the central nervous system that generally develops 7-10 years after infection. From 1989 through 1991, a resurgence of measles occurred in the United States, with 55,622 cases of measles reported. The purpose of the present study was to identify cases of SSPE that were associated with the resurgence of measles and to calculate the risk of developing SSPE.

METHODS

Brain tissue samples obtained from 11 patients with a presumptive diagnosis of SSPE were tested for the presence of measles virus RNA. Measles virus genotypes were determined by reverse-transcription polymerase chain reaction (RT-PCR) and by analysis of the sequences of the PCR products. A search of the literature was conducted to identify reports of cases of SSPE in persons residing in the United States who had measles during 1989-1991.

RESULTS

The measles virus sequences derived from brain tissue samples obtained from 11 patients with SSPE confirmed the diagnosis of SSPE. For 5 of the 11 patients with SSPE who had samples tested by RT-PCR and for 7 patients with SSPE who were identified in published case reports, it was determined that the development of SSPE was associated with the measles resurgence that occurred in the United States during 1989-1991. The estimated risk of developing SSPE was 10-fold higher than the previous estimate reported for the United States in 1982.

CONCLUSIONS

Vaccination against measles prevents more cases of SSPE than was originally estimated.

Subacute Sclerosing Panencephalitis in Bulgaria (1978–2002)

The epidemiology of subacute sclerosing panencephalitis (SSPE) has changed substantially since the introduction of measles vaccine. We studied the incidence of SSPE in Bulgaria based on cases admitted to the Child Neurology Clinic, University Hospital of Neurology and Psychiatry, Sofia, for a 25-year period (1978-2002). The SSPE incidence prior to and during the period of routine measles immunization was analyzed. SSPE was diagnosed in 40 children (29 males and 11 females, mean age 8.5 years), 28 from 1978 to 1984 (average 4 patients/year), and 12 from 1995 to 2002 (average 1.7 patients/year). Thirty-eight cases (95%) were non-immunized and had early measles infection. Age at onset of SSPE ranged from 8 to 11 years (52.5%) with a mean latent period of 7 years following measles infection. The increase in SSPE incidence (1995-2002) following a 10-year disease-free period (1985-1994) appears to be related to early measles infection (mean age 11 months) during the measles epidemic of 1991-1992. During the period 1995-2002, children had earlier measles infection (average 11 months) and earlier onset of SSPE (mean age 8.4 years) than in the period 1978-1984 (mean age at measles infection 18 months, and of SSPE onset 11.2 years). The SSPE incidence in Bulgaria during the 25-year period from 1978 to 2002 confirms the importance of early measles infection as a risk factor for SSPE, and the role of routine measles immunization in SSPE prevention.

Changing epidemiological features of subacute sclerosing panencephalitis

BACKGROUND

Subacute sclerosing panencephalitis (SSPE) is a chronic central nervous (CNS) system infection caused by measles virus. Because changing immunization practices affect the epidemiology of measles and consequently SSPE, we examined the epidemiological data of our SSPE registry.

MATERIALS AND METHODS

Age of onset, age at onset of measles, duration of Latent period and immunization status were examined in cases recorded at the SSPE Registry Center in Turkey between 1975 and 1999.

RESULTS

Age of onset diminished from 13 years before 1994 to 7.6 years after 1995; age at onset of measles declined from 29 months to 20 months and the Latent interval from 9.9 years to 5.9 years. Age at onset of measles and immunization status did not directly affect the duration of the Latent period.

CONCLUSION

Although its incidence has decreased in Turkey, SSPE has been seen at younger ages in recent years. This change cannot be attributed solely to younger age at onset of measles. Factors affecting the duration of the Latent period should be investigated further.

Salmonella vaccines secreting measles virus epitopes induce protective immune responses against measles virus encephalitis

In the present study we describe a live vaccine against measles virus (MV) infection on the basis of attenuated Salmonella typhimurium aroA secreting MV antigens via the Escherichia coli alpha-hemolysin secretion system. Two well-characterized MV epitopes, a B-cell epitope of the MV fusion protein (amino acids 404-414) and a T-cell epitope of the MV nucleocapsid protein (amino acids 79-99) were fused as single or repeating units to the C-terminal secretion signal of the E. coli hemolysin and expressed in secreted form by the attenuated S. typhimurium aroA SL7207. Immunization of MV-susceptible C3H mice revealed that S. typhimurium SL7207 secreting these antigens provoked a humoral and a cellular MV-specific immune response, respectively. Mice vaccinated orally with a combination of both recombinant S. typhimurium strains showed partial protection against a lethal MV encephalitis after intracerebral challenge with a rodent-adapted, neurotropic MV strain.

Isolation of a measles virus variant: protection of newborn mice from measles encephalitis by 24 h prior intracerebral inoculation with the variant

A small plaque mutant with reduced neurovirulence in newborn mice was obtained from Edmonston strain measles virus after propagation for 5 months in NIH3T3 cells. It retained the antigenicity of the parental virus and tended to induce higher neutralizing antibody titers in the adult BALB/c mice. The intracerebral (but not intraperitoneal) inoculation of the live mutant virus one day before prevented the newborn BALB/c mice from encephalitis caused by the intracerebral challenge with the parental strain at a dose of 10-20 LD50. The intracerebral inoculation with the mutant virus whose replication capacity was inactivated by UV-irradiation was ineffective. The protection was not attributed to interferons nor to viral interference. The mechanism remains unknown.

[Evaluation of changes in the epidemiological situation of SSPE in Poland in the years 1977-1991 (in the course of 15 years after the introduction of mandatory antimeasles vaccination)]

The authors present the results of an epidemiological study of SSPE in Poland conducted since 15 years. Since the years covered by the study (1977-1991) included the first period after the introduction of obligatory vaccinations against measles in our country, the most important aim of this analysis was to find out the possible influence of the effect of these vaccinations on SSPE incidence. A comparison of the data obtained in successive stages of the study shows that a slow gradual decrease of the annual incidence of SSPE has been taking place in our country (from at least 1.6 per million before 1983 to 0.69 in 1991). The effect of the vaccinations is visible also in a significant increase of the mean age of SSPE onset which is a result of ever more widespread vaccination of the youngest children. These observations indicate unequivocally that the aetiological factor in SSPE is a wild strain of measles virus and not that used for vaccinations.

Subacute sclerosing panencephalitis in The Netherlands--1976-1990

Since 1976, when general immunization against measles was introduced in the Netherlands, all new cases of subacute sclerosing panencephalitis (SSPE) were registered and detailed data about immunization, epidemiology and disease progression were collected on them. Up to 1991, 99 new patients have been registered of which 81 were born in this country and 18 elsewhere. From 1981 onwards, the incidence of SSPE among those born in the Netherlands decreased gradually from 13 cases per year to one case per year. This decrease is attributed to the large scale of immunization against measles. Three SSPE patients had been immunized against measles, all of them without a history of clinical measles. Epidemiology and risk factors of SSPE did not differ from those reported in other countries. An exceptional cluster of four patients in one town, who had measles in the same year, is reported. Progression of SSPE appeared to be age related. A total of 28 patients was treated with Inosiplex; no significant effect on survival in stage 3 of the disease was found.

SSPE: but we thought measles was gone!

Subacute sclerosing panencephalitis (SSPE) is a progressive neurodegenerative disease caused by the measles (rubeola) virus and is most often seen in children. Many affected children have a history of measles infection in the first years of life or exposure to the live measles virus vaccine. Typically, there is a rapid onset of neurological symptoms degenerating into a stuporous state in the patient. Four children and their families are reviewed. Their individual courses, medical and nursing problems and interventions, and implications for immunizations with the measles-mumps-rubella (MMR) vaccine will be discussed.

The continuous decrease in the number of SSPE annual cases ten years after compulsory anti-measles immunization

The record of SSPE cases diagnosed immunochemically and serologically in our laboratory, standing for about 60% of the total new cases reported in our country, shows a significant decrease in the incidence in 1988-89 (from 5.21 new cases per year per million total population in 1987 to 1.82 cases in 1988). In 85% of the patients, SSPE onset occurred at the age of 10 years or more, suggesting the possibility of a primary measles infection before anti-measles immunization became compulsory. High serum and CSF anti-measles antibody titres in recently diagnosed patients show subclinical long-term courses. Further serologic tests for viruses inducing persistent infections (herpes viruses, AgHBs and HIV) do not show any difference when compared to a control group excepting an increased incidence of anti-cytomegalic titres.

Subacute sclerosing panencephalitis in Northern Ireland: twenty years' experience

Subacute sclerosing panencephalitis (SSPE) is a rare degenerative disease of the central nervous system that affects primarily children and adolescents. It is a late manifestation of measles virus infection. In a 20-year period (1965-85) there have been 26 cases of SSPE in Northern Ireland, a frequency of approximately one case per 1.2 million population per year. Males were affected more frequently than females. In other parts of the world the incidence of this disease has been dramatically reduced following effective measles immunisation programmes. The vaccination rate in Northern Ireland probably remains too low to have a similar effect.

Protective effect of measles virus inoculation on subacute sclerosing panencephalitis virus-infected mice

The Biken strain of subacute sclerosing panencephalitis (SSPE) virus caused a fatal neurologic disease in adult mice after intracerebral inoculation. However, the mice were completely protected from the disease when a high dose of measles virus was given intracerebrally after the SSPE virus infection. The measles virus inoculation induced interferon production and immune responses. An experiment with athymic nude mice showed that interferon and anti-measles antibody were able to prolong the incubation period of the disease but not to protect the SSPE virus-infected nude mice from death. For complete protection, T lymphocytes appeared to be essential. The present study suggested that the protective effect of measles virus inoculation is basically due to the induction of immune responses and that SSPE virus infection in mice is susceptible to immune reactions.

Health impact of measles vaccination in the United States

As a result of intensive efforts to vaccinate children, measles and its attendant complications of encephalitis and death have declined more than 99% from the prevaccine era. Similarly, subacute sclerosing panencephalitis has declined markedly. Measles vaccine has been demonstrated to be extremely safe, as well as extremely effective. The health and resource benefits due to vaccination against measles during the first 20 years of vaccine licensure have been enormous. In this period it is estimated that vaccination against measles has prevented 52 million cases, 5,200 deaths, and 17,400 cases of mental retardation, achieving a net savings of $5.1 billion. These substantial health and resource benefits of measles vaccination will continue to accrue in the future.